How did the bushpig cross the strait? A great puzzle in African mammal biogeography solved by genomics

Africa has a huge diversity of large mammals, but their evolutionary relationships and movement across the continent over time often remain a mystery. A new scientific study sheds light on longstanding questions about the interplay between evolution and geography in one of these mammals, namely the iconic African bushpig, and helps settle a major question regarding prehistoric human activities shaping biodiversity patterns in Africa.

In the ongoing biodiversity crisis, large terrestrial animals are more threatened by extinction than any other group of organisms. The African continent holds an impressively intact large-mammal community, but there is still a lot we do not know about how these species evolved, became diverse and adapted to the changing climate and habitats. Many of these questions can be addressed by investigating the genomes and genetic variation across species.

New research, published in Nature Communications, uses genomics to answer these evolutionary questions that have been debated amongst scientists for decades: 1) how and when did bushpigs cross the Mozambique Channel and arrive at the island of Madagascar, 2) is there one or two species of bushpigs?

"This study is a result of a large international collaboration with researchers from Africa and Europe. We sequenced 67 complete bushpig genomes and by using a range of different genetic analyses, we were able to address these long-standing puzzles in African evolution and biogeography," explains one of the senior authors of the study, Associate Professor at the Department of Biology, Rasmus Heller.

Were pigs ferried across the channel during the Medieval era?

The island of Madagascar separated from the African mainland around 160 million years ago, resulting in a largely unique flora and fauna. Remarkably, the bushpig is the only large, wild terrestrial mammal species that has somehow historically crossed the 400-kilometer-wide Mozambique Channel and made it from mainland Africa to the island of Madagascar.

"Our study establishes that the bushpig was introduced to Madagascar ≈1,000-5,000 years ago from South/South-East Africa," Rasmus states. Their arrival therefore coincides with the arrival of humans to Madagascar from a region around southern Africa. Rasmus continues: "The likely explanation for this is that people transported these bushpigs across the channel. These results contradict previously published studies which dated the arrival of bushpigs ≈480,000 years ago, well before humans were present on the island." It has been suggested that some endemic Madagascar species might have arrived by rafting as passengers on floats of vegetation.

"Intriguingly, our results raise a host of new questions: was the bushpig actually brought to Madagascar as a somewhat domesticated species? There is no archaeological or other evidence of bushpig domestication ever occurring, despite them being an important source of protein for many rural communities. And who was it that transported these animals to Madagascar? Was it Bantu-speakers, Austronesian-speakers or both? These questions and others still remain to be explored," explains Renzo F. Balboa, postdoc at the Department of Biology and one of the leading authors of the study.

Does two actually equal one?

African bushpigs, which primarily are found in East/Southern Africa, and red river hogs, which are found in West/Central Africa, were considered the same species in the past, but were subsequently redefined as two species around the 1990s, largely due to their quite distinctive looks.

The red river hogs are, as the name implies red, and have long, tufted ears reminiscent of a comical Star Wars character, while eastern and southern African bushpigs are greyish and look more like our own wild boar, although with a beautiful white mane thrown in for good measure.

Biologists have been arguing for decades about whether these two forms are actually one or two different species -- a debate that is characteristic of similar scientific uncertainty surrounding many other African mammals.

"In this study, we were able to conclude that red river hogs and bushpigs have had lots of gene flow, which means they are not only able to potentially interbreed, but they have in fact done so extensively when they have met in central Africa. Furthermore, the branching of the two types in the Tree of Life is not all that old, only a few hundred thousand years, which is not long in the evolutionary scheme of things. Hence, we now know that although there are two quite different-looking lineages of bushpigs, their biological separation is incomplete, depending on how you define species," explains Laura D. Bertola, postdoc at the Department of Biology and the other leading author of the study.

Laura continues: "Genomic data can give us insights into patterns of biodiversity on a much higher resolution than previously possible. For example, we can infer detailed population structure, but also underlying processes like gene flow and selection. Gaining improved insights into patterns of biodiversity and the underlying processes that drive them, will be crucial for effective conservation measures."

Africa is a unique continent regarding the diversity of the megafauna which is still around. Studying the evolutionary history of these species can give us important insights into African biodiversity, which is highly relevant at a time where biodiversity is being lost at an alarming pace. The new findings contribute to our understanding of prehistoric relations between Africa's humans and wildlife, but also the very fundamentals about how much biodiversity there is on this amazing continent.

"This study is a great example of how involving local researchers and wildlife management authorities can lead to more robust and inclusive scientific research," co-author Vincent Muwanika, Associate Professor of Conservation Biology, at Makerere University, Uganda, concludes.

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Raining cats and dogs: Global precipitation patterns a driver for animal diversity

Since the HMS Beagle arrived in the Galapagos with Charles Darwin to meet a fateful family of finches, ecologists have struggled to understand a particularly perplexing question: Why is there a ridiculous abundance of species some places on earth and a scarcity in others? What factors, exactly, drive animal diversity?

With access to a mammoth set of global-scale climate data and a novel strategy, a team from the Department of Watershed Sciences in Quinney College of Natural Resources and the Ecology Center identified several factors to help answer this fundamental ecological question. They discovered that what an animal eats (and how that interacts with climate) shapes Earth's diversity.

The work was recently published in the high-impact journal Ecology Letters.

"Historically studies looking at the distribution of species across Earth's latitudinal gradient have overlooked the role of trophic ecology -- how what animals eat impacts where they are found," said Trisha Atwood, author on the study from the Department of Watershed Sciences and the Ecology Center. "This new work shows that predators, omnivores and herbivores are not randomly scattered across the globe. There are patterns to where we find these groups of animals."

Certain locations have an unexpected abundance of meat-eating predators -- parts of Africa, Europe and Greenland. Herbivores are common in cooler areas, and omnivores tend to be more dominant in warm places. Two key factors emerged as crucial in shaping these patterns: precipitation and plant growth.

Precipitation patterns across time play a big role in determining where different groups of mammals thrive, Atwood said. Geographical areas where precipitation varies by season, without being too extreme, had the highest levels of mammal diversity.

"Keep in mind that we aren't talking about the total amount of rain," said Jaron Adkins, lead author on the research. "If you imagine ecosystems around the world on a scale of precipitation and season, certain places in Utah and the Amazon rainforest fall on one end with low variability -- they have steady levels of precipitation throughout the year. Other regions, like southern California, have really high variability, getting about 75 percent of the annual precipitation between December and March."

But the sweet spot for predators and herbivores fell in a middle zone between the two extremes, he said. Places like Madagascar, where precipitation patterns had an equal split between a wet season and a dry one (six months each), had the ideal ecological cocktail for promoting conditions for these two groups. Omnivore diversity tends to thrive in places with very stable climates.

The second important factor connected with mammal diversity the work uncovered was a measure of the amount of plant growth in an area, measured as "gross primary productivity."

"It makes intuitive sense for plant-eating animals to benefit from plant growth," Adkins said.

But this measure actually impacted carnivores most, according to the research. The strong relationship between predators and plant growth highlights the importance of an abundance of plants on an entire food chain's structural integrity.

"It was surprising that this factor was more important for predators than omnivores and herbivores," Atwood said. "Why this is remains a mystery."

Although evolutionary processes are ultimately responsible for spurring differences in species, climate conditions can impact related factors -- rates of evolutionary change, extinction and animal dispersal -- influencing species and trait-based richness, according to the research.

Animal diversity is rapidly declining in many ecosystems around the world through habitat loss and climate change. This has negative consequences for ecosystems. Forecasting how climate change will disrupt animal systems going forward is extremely important, Atwood said, and this research is a first step in better managing future conditions for animals around the world.

"Animal diversity can act as an alarm system for the stability of ecosystems," Atwood said. "Identifying the ecological mechanisms that help drive richness patterns provides insight for better managing and predicting how diversity could change under future climates."

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Dog diversity unveiled by international DNA database

An international consortium of scientists, led by Jeff Kidd, Ph.D. of University of Michigan, Jennifer R. S. Meadows of Uppsala University in Sweden, and Elaine A. Ostrander, Ph.D. of the NIH National Human Genome Research Institute, is using an unprecedentedly large database of canine DNA to take an unbiased look at how our furry friends evolved into the various breeds we know and love.

A new paper, published in the journal Genome Biology, outlines what the Dog10K project discovered after sequencing the genomes of close to 2000 samples from 321 different breed dogs, wild dogs, coyotes, and wolves, and comparing them to one reference sample -- that of a German Shepherd named Mischka.

Analyzing more than 48 million pieces of genetic information, they discovered that each breed dog had around 3 million single nucleotide polymorphism differences. These SNPs or "snips" are what account for most of the genetic variation among people and dogs alike. They also found 26,000 deleted sequences that were present in the German Shepherd but not in the comparison breed and 14,000 that were in the compared breed but missing from Mischka's DNA.

"We did an analysis to see how similar the dogs were to each other, and it ended up that we could divide them into around 25 major groups that pretty much match up with what people would have expected based on breed origin, the dogs' type, size and coloration," said Kidd, a professor of Human Genetics and Computational Medicine and Bioinformatics at the U-M Medical School.

Most of the varying genes, he added, had to do with morphology, confirming that the breed differences were driven by how the dogs look.

Relative to dogs, wolves had around 14 percent more variation. And wild village dogs -- dogs that live amongst people in villages or cities but aren't kept as pets -- exhibited more genetic variation than breed dogs.

The data set, which was processed using the Great Lakes high-performing computing cluster at U-M, also revealed an unusual amount of retrogenes, a new gene that forms when RNA gets turned back into DNA and inserted back into the genome in a different spot. The study found 926 retrogenes, the most famous of which, says Kidd, is a retrogene called FGF4, which results in the short leg phenotype seen in dachshunds and corgis.

"Dogs tend to have an increased amount of retrogenes which have resulted in mutations that were selected for, that perhaps people found cute and bred more of," said Kidd. His lab is attempting to figure out why retrogenes and insertions happen so frequently in dogs.

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Newly discovered 'primitive cousins of T rex' shed light on the end of the age of dinosaurs in Africa

Fossils of primitive cousins of T. rex that had short, bulldog snouts and even shorter arms have been discovered by scientists in Morocco. The two new dinosaur species belong to the Abelisauridae, a family of carnivorous dinosaurs that were counterparts to the tyrannosaurs of the Northern Hemisphere. They lived at the end of the Cretaceous period and show that dinosaurs were diverse in Africa just before their mass extinction by an asteroid 66 million years ago.

Two new species of dinosaur have been found from the end of the Cretaceous in Morocco, just outside of Casablanca. One species, found near the town of Sidi Daoui, is represented by a foot bone from a predator about two and a half metres (eight feet) long. The other, from nearby Sidi Chennane, is the shin bone of a carnivore that grew to around five metres (15 feet) in length.

Both were part of a family of primitive carnivorous dinosaurs known as abelisaurs, and lived alongside the much larger abelisaur Chenanisaurus barbaricus, showing that Morocco was home to diverse dinosaur species just before a giant asteroid struck at the end of the Cretaceous, ending the age of dinosaurs.

Dr Nick Longrich, from the Milner Centre for Evolution at the University of Bath, led the study. He said: "What's surprising here is that these are marine beds.

"It's a shallow, tropical sea full of plesiosaurs, mosasaurs, and sharks. It's not exactly a place you'd expect to find a lot of dinosaurs. But we're finding them."

Even though dinosaurs account for a small proportion of the fossils, the region is so rich in fossils, it has produced the best picture of African dinosaurs from the end of the age of dinosaurs.

Rather than finding the same few species, palaeontologists often recover fossils from new species, suggesting the beds host an extremely diverse dinosaur fauna.

So far, the small number of dinosaur fossils that have been recovered represent five different species -- a small duckbill dinosaur named Ajnabia, a long-necked titanosaur, the giant abelisaur Chenanisaurus, and now the two new abelisaurs.

Dr Longrich said: "We have other fossils as well, but they're currently under study. So we can't say much about them at the moment, except that this was an amazingly diverse dinosaur fauna."

The last dinosaurs vanished around 66 million years ago, along with as much as 90% of all species on earth, including mosasaurs, plesiosaurs, pterosaurs and ammonites. The pattern of the end-Cretaceous extinction and its causes have been debated for over two hundred years.

A giant asteroid impact in the Yucatan peninsula has been linked to their demise, although it's been argued that dinosaurs were already in decline. The Moroccan dinosaurs suggest that they thrived in North Africa up to the very end.

"The end of the Cretaceous in western North America definitely seems to become less diverse at the end," said Longrich. "But that's just one small part of the world. It's not clear that you can generalise from the dinosaurs of Wyoming and Montana to the whole world.

"It also grew colder near the end, so it might not be surprising if dinosaurs at higher latitudes became less diverse. But we don't know much about dinosaurs from lower latitudes."

In Morocco at least, they seem to have remained diverse and successful up until the end.

"When T. rex reigned as a megapredator in North America, abelisaurs sat at the top of the food chains in North Africa," said Nour-Eddine Jalil, a professor at the Natural History Museum and a researcher at Universite Cadi Ayyad in Morocco, who was a co-author on the paper.

"The dinosaur remains, despite their rarity, give the same messages as the more abundant marine reptile remains.

"They tell us that, just before the Cretaceous-Paleogene crisis, biodiversity was not declining but on the contrary, was diverse."

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Researchers extract ancient DNA from a 2,900-year-old clay brick, revealing a time capsule of plant life

Currently housed at the National Museum of Denmark, the clay brick originates from the palace of Neo-Assyrian king Ashurnasirpal II, in the ancient city of Kalhu. Known today as the North-West palace in Nimrud (modern-day northern Iraq), its construction began around 879 BCE. The brick has a cuneiform inscription (written in the now extinct Semitic language Akkadian) stating that it is 'The property of the palace of Ashurnasirpal, king of Assyria.' This makes it possible to date the brick precisely to within a decade (879 BCE to 869 BCE).

During a digitalization project at the Museum in 2020, the group of researchers were able to obtain samples from the inner core of the brick -- meaning that there was a low risk of DNA contamination since the brick was created. The team extracted DNA from the samples by adapting a protocol previously used for other porous materials, such as bone.

After the extracted DNA had been sequenced, the researchers identified 34 distinct taxonomic groups of plants. The plant families with the most abundant sequences were Brassicaceae (cabbage) and Ericaceae (heather). Other represented families were Betulaceae (birch), Lauraceae (laurels), Selineae (umbellifiers) and Triticeae (cultivated grasses).

With the interdisciplinary team comprising assyriologists, archaeologists, biologists, and geneticists, they were able to compare their findings with modern-day botanical records from Iraq as well as ancient Assyrian plant descriptions.

The brick would have been made primarily of mud collected near the local Tigris river, mixed with material such as chaff or straw, or animal dung. It would have been shaped in a mould before being inscribed with cuneiform script, then left in the sun to dry. The fact that the brick was never burned, but left to dry naturally, would have helped to preserve the genetic material trapped within the clay.

Dr Sophie Lund Rasmussen (Wildlife Conservation Research Unit, Department of Biology, University of Oxford), joint first author of the paper, said: 'We were absolutely thrilled to discover that ancient DNA, effectively protected from contamination inside a mass of clay, can successfully be extracted from a 2,900-year-old clay brick. This research project is a perfect example of the importance of interdisciplinary collaboration in science, as the diverse expertise included in this study provided a holistic approach to the investigation of this material and the results it yielded.'

In addition to the fascinating insight this individual brick revealed, the research serves as a proof of concept and method which could be applied to many other archaeological sources of clay from different places and time periods around the world, to identify past flora and fauna. Clay materials are nearly always present in any archaeological site around the world, and their context means they can often be dated with high precision.

This study only described the plant DNA extracted, as these were the most prevalent and best-preserved specimens. However, depending on the sample, all taxa could potentially be identified, including vertebrates and invertebrates. The ability to provide accurate descriptions of ancient biodiversity would be a valuable tool to better understand and quantify present day biodiversity loss, and to gain a deeper understanding of ancient and lost civilisations.

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Oldest known species of swimming jellyfish identified

Royal Ontario Museum (ROM) announces the oldest swimming jellyfish in the fossil record with the newly named Burgessomedusa phasmiformis. These findings are announced in the journal Proceedings of the Royal Society B.

Jellyfish belong to medusozoans, or animals producing medusae, and include today's box jellies, hydroids, stalked jellyfish and true jellyfish. Medusozoans are part of one of the oldest groups of animals to have existed, called Cnidaria, a group which also includes corals and sea anemones. Burgessomedusa unambiguously shows that large, swimming jellyfish with a typical saucer or bell-shaped body had already evolved more than 500 million years ago.

Burgessomedusa fossils are exceptionally well preserved at the Burgess Shale considering jellyfish are roughly 95% composed of water. ROM holds close to two hundred specimens from which remarkable details of internal anatomy and tentacles can be observed, with some specimens reaching more than 20 centimetres in length. These details enable classifying Burgessomedusa as amedusozoan. By comparison with modern jellyfish, Burgessomedusa would also have been capable of free-swimming and the presence of tentacles would have enabled capturing sizeable prey.

"Although jellyfish and their relatives are thought to be one of the earliest animal groups to have evolved, they have been remarkably hard to pin down in the Cambrian fossil record. This discovery leaves no doubt they were swimming about at that time," said co-author Joe Moysiuk, a Ph.D. candidate in Ecology & Evolutionary Biology at the University of Toronto, who is based at ROM.

This study, identifying Burgessomedusa, is based on fossil specimens discovered at the Burgess Shale and mostly found in the late 1980s and 1990s under former ROM Curator of Invertebrate Palaeontology Desmond Collins. They show that the Cambrian food chain was far more complex than previously thought, and that predation was not limited to large swimming arthropods like Anomalocaris (see field image showing Burgessomedusa and Anomalocaris preserved on the same rock surface).

"Finding such incredibly delicate animals preserved in rock layers on top of these mountains is such a wonderous discovery. Burgessomedusa adds to the complexity of Cambrian foodwebs, and like Anomalocaris which lived in the same environment, these jellyfish were efficient swimming predators," said co-author, Dr. Jean-Bernard Caron, ROM's Richard Ivey Curator of Invertebrate Palaeontology. "This adds yet another remarkable lineage of animals that the Burgess Shale has preserved chronicling the evolution of life on Earth."

Cnidarians have complex life cycles with one or two body forms, a vase-shaped body, called a polyp, and in medusozoans, a bell or saucer-shaped body, called a medusa or jellyfish, which can be free-swimming or not. While fossilized polyps are known in ca. 560-million-year-old rocks, the origin of the free-swimming medusa or jellyfish is not well understood. Fossils of any type of jellyfish are extremely rare. As a consequence, their evolutionary history is based on microscopic fossilized larval stages and the results of molecular studies from living species (modelling of divergence times of DNA sequences). Though some fossils of comb-jellies have also been found at the Burgess Shale and in other Cambrian deposits, and may superficially resemble medusozoan jellyfish from the phylum Cnidaria, comb-jellies are actually from a quite separate phylum of animals called Ctenophora. Previous reports of Cambrian swimming jellyfish are reinterpreted as ctenophores.

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Form and function of island and mainland plants

Oceanic islands provide useful models for ecology, biogeography and evolutionary research. Many ground-breaking findings -- including Darwin's theory of evolution -- have emerged from the study of species on islands and their interplay with their living and non-living environment. Now, an international research team led by the University of Göttingen has investigated the flora of the Canary Island of Tenerife. The results were surprising: the island's plant-life exhibits a remarkable diversity of forms. But the plants differ little from mainland plants in functional terms. However, unlike the flora of the mainland, the flora of Tenerife is dominated by slow-growing, woody shrubs with a "low-risk" life strategy. The results were published in Nature.

The researchers investigated how the plants of Tenerife differ in functional terms from plants from other parts of the world. They conducted extensive field research and measurements at over 500 sites using the most up-to-date methods of functional ecology. The sites were scattered all over the island at altitudes ranging from sea level to mountainous regions above 3,300 metres. The scientists recorded about 80% of Tenerife's native seed plants, and surveyed eight plant characteristics: plant size, specific wood density, leaf thickness, absolute and specific leaf area, leaf dry matter, nitrogen concentration in leaf tissue, and seed weight. They compared their data with data on more than 2,000 plant species found on the mainland.

"Our study shows, for the first time and contrary to all expectations, that species groups that evolved on the Canary Islands do not contribute to the expansion of the breadth of different traits. This means they do not lead to more functional diversity," explains the lead of the study, Professor Holger Kreft, and Göttingen University's Biodiversity, Macroecology and Biogeography research group. Previous comparisons show that species occurring on islands can differ significantly from their relatives on the mainland. A well-known example is provided by the Galapagos giant tortoise: the species is only found on the Galapagos Islands and, as a result of adaptation to its environmental conditions, is much larger than tortoises from the mainland. The research team expected similar differences between island and mainland plants, but this was not the case. "Rather, we see that most species follow the constraints of the island climate. Thus, medium-sized, woody species develop. These tend to live with the limited resources and high risks of extinction on the island. That is, they grow slowly. The high functional diversity is mainly due to the species that are widespread on the island and the nearby mainland," explains Kreft.

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Scientists discover 36-million-year geological cycle that drives biodiversity

Movement in the Earth's tectonic plates indirectly triggers bursts of biodiversity in 36-million-year cycles by forcing sea levels to rise and fall, new research has shown.

Researchers including geoscientists at the University of Sydney believe these geologically driven cycles of sea level changes have a significant impact on the diversity of marine species, going back at least 250 million years.

As water levels rise and fall, different habitats on the continental shelves and in shallow seas expand and contract, providing opportunities for organisms to thrive or die. By studying the fossil record, the scientists have shown that these shifts trigger bursts of new life to emerge.

The research has been published in the journal Proceedings of the National Academy of Sciences, led by Associate Professor Slah Boulila from Sorbonne University in Paris.

Study co-author Professor Dietmar Müller, from the School of Geosciences at the University of Sydney, said: "In terms of tectonics, the 36-million-year cycle marks alterations between faster and slower seafloor spreading, leading to cyclical depth changes in ocean basins and in the tectonic transfer of water into the deep Earth.

"These in turn have led to fluctuations in the flooding and drying up of continents, with periods of extensive shallow seas fostering biodiversity.

"This work was enabled by the GPlates plate tectonic software, developed by the EarthByte Group at the University of Sydney, supported by Australia's National Collaborative Research Infrastructure Strategy (NCRIS) via AuScope."

The team based their findings on the discovery of strikingly similar cycles in sea-level variations, Earth's interior mechanisms and marine fossil records.

Scientists now have overwhelming evidence that tectonic cycles and global sea level change driven by Earth's dynamics have played a crucial role in shaping the biodiversity of marine life over millions of years.

"This research challenges previous ideas about why species have changed over long periods," Professor Müller said.

"The cycles are 36 million years long because of regular patterns in how tectonic plates are recycled into the convecting mantle, the mobile part of the deep Earth, similar to hot, thick soup in a pot, that moves slowly."

Professor Müller said the Cretaceous Winton Formation in Queensland serves as a prime example of how sea-level changes have shaped ecosystems and influenced biodiversity in Australia.

The formation, renowned for its collection of dinosaur fossils and precious opal, provides a valuable window into a time when much of the Australian continent was flooded.

As sea levels rose and fell, the flooding of the continent created expanding and contracting ecological recesses in shallow seas, providing unique habitats for a wide range of species.

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New dinosaur discovered: Ankylosaurs may have been far more diverse than originally thought

A new armoured dinosaur, known as an ankylosaur, has been described and named for Prof Paul Barrett of the Natural History Museum.

Vectipelta barretti was discovered in the Wessex formation on the Isle of Wight and represents the first armoured dinosaur from the dinosaur Isle to be described in 142 years.

Lead author Stuart Pond explained the importance of this find, 'This is an important specimen because it sheds light on ankylosaur diversity within the Wessex formation and Early Cretaceous England.

'For virtually 142 years, all ankylosaur remains from the Isle of Wight have been assigned to Polacanthus foxii, a famous dinosaur from the island, now all of those finds need to be revisited because we've described this new species.'

The new species differs from Polacanthus foxii, previously the only known ankylosaur from the Isle of Wight, in several key characteristics. The fossilized remains show differences in the neck and back vertebrae, a very different structure to the pelvis and more blade-like spiked armour.

The researchers used phylogenetic analysis to work out the relationships between different ankylosaurs and discovered that they are not actually very closely related. In fact, Vectipelta was found to be most closely related to some Chinese ankylosaurs, suggesting dinosaurs moved freely from Asia to Europe in the Early Cretaceous.

Vectipelta barretti would have been roaming the earth during the Early Cretaceous, a time for which fossil remains are rare worldwide. This has led some to suggest that a mass extinction occurred at the end of the Jurassic, which makes the understanding of dinosaur diversity at this time crucial to understanding if such an event occurred and how life recovered. With rocks from this time mostly absent in North America, the Wessex Formation and the Isle of Wight are hugely important areas in answering these questions.

At the time the Isle of Wight would have had a climate similar to that of the Mediterranean and was a flood plain covered by a large meandering river system. Floods would have washed organic material such as plants, logs and even dinosaur bodies together and, as waters receded, this organic matter would have been isolated in ponds on the floodplain that eventually dried out and were buried in the clay soil, preserving this organic material as the fossils we find today.

On naming the new dinosaur for Prof Paul Barrett of the Natural History Museum, senior author Dr Susannah Maidment said, 'Myself and some of the other authors on this study have been mentored or supervised by Paul for most of our careers, and it was notable to us that Paul hadn't had a dinosaur named after him yet. He's hugely influential in in vertebrate palaeontology, and he's a world-leading authority on dinosaurs.

'We really wanted to thank him for his support and mentorship, so we decided to name a, slow-moving, spikey organism after him.'

Prof Paul Barrett has worked at the Natural History Museum, London for 20 years and in that time has published an impressive 220 scientific papers. He has also supervised 31 PhD students and mentored many others, encouraging a whole new generation of palaeontologists.

Of the honour Prof Barrett said, 'I'm flattered and absolutely delighted to have been recognised in this way, not least as the first paper I ever wrote was also on an armoured dinosaur in the NHM collections. I'm sure that any physical resemblance is purely accidental.'

The team are optimistic that more species will be discovered in the area in the future. Dr Maidment concluded, 'We have new iguanodontians that we are lining up, to be prepped and to be studied. I think we have at least two new taxa in the collections. With regards to ankylosaurs, they are somewhat rarer, so I think we need to keep our eyes peeled.'

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Human ancestors preferred mosaic landscapes and high ecosystem diversity

A new study published in the journal Science by an international team finds that early human species adapted to mosaic landscapes and diverse food resources, which would have increased our ancestor's resilience to past shifts in climate.

Our genus Homo evolved over the past 3 million years -- a period of increasing warm/cold climate fluctuations. How early human species have adapted to the intensification of climate extremes, ice ages, and large-scale shifts in landscapes and vegetation remains elusive. Did our ancestors adjust to local environmental changes over time, or did they seek out more stable environments with diverse food resources? Was our human evolution influenced more by temporal changes in climate, or by the spatial character of the environment?

To test these fundamental hypotheses on human evolution and adaptation quantitively, the research team used a compilation of more than three thousand well-dated human fossil specimens and archeological sites, representing six different human species, in combination with realistic climate and vegetation model simulations, covering the past 3 million years. The scientists focused their analysis on biomes -- geographic regions which are characterized by similar climates, plants, and animal communities (e.g., savannah, rainforest, or tundra).

"For the archeological and anthropological sites and corresponding ages, we extracted the local biome types from our climate-driven vegetation model. This revealed which biomes were favored by the extinct hominin species H. ergaster, H. habilis, H. erectus, H. heidelbergensis, and H. neanderthalensis andbyour direct ancestors -- H. sapiens.," said Elke Zeller, Ph.D. student from the IBS Center for Climate Physics at Pusan National University, South Korea, and lead author of the study.

According to their analysis, the scientists found that earlier African groups preferred to live in open environments, such as grassland and dry shrubland. Migrating into Eurasia around 1.8 million years ago, hominins, such as H. erectus and later H. heidelbergensis and H. neanderthalensis developed higher tolerances to other biomes over time, including temperate and boreal forests. "To survive as forest-dwellers, these groups developed more advanced stone tools and likely also social skills," said Prof. Pasquale Raia, from the Università di Napoli Federico II, Italy, co-author of the study. Eventually, H. sapiens emerged around 200,000 years ago in Africa, quickly becoming the master of all trades. Mobile, flexible, and competitive, our direct ancestors, unlike any other species before, survived in harsh environments such as deserts and tundra.

When further looking into the preferred landscape characteristics, the scientists found a significant clustering of early human occupation sites in regions with increased biome diversity. "What that means is that our human ancestors had a liking for mosaic landscapes, with a great variety of plant and animal resources in close proximity," said Prof. Axel Timmermann, co-author of the study and Director of the IBS Center for Climate Physics in South Korea. The results indicate that ecosystem diversity played a key role in human evolution.

The authors demonstrated this preference for mosaic landscapes for the first time on continental scales and propose a new Diversity Selection Hypothesis: Homo species, and H. sapiens, in particular, were uniquely equipped to exploit heterogeneous biomes. "Our analysis shows the crucial importance of landscape and plant diversity as a selective element for humans and as a potential driver for socio-cultural developments" adds Elke Zeller. Elucidating how vegetation shifts have shaped human sustenance, the new Science study provides an unprecedented view into human prehistory and survival strategies.

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Clearest snapshot of human genomic diversity

For more than 20 years, scientists have relied on the human reference genome, a consensus genetic sequence, as a standard against which to compare other genetic data. Used in countless studies, the reference genome has made it possible to identify genes implicated in specific diseases and trace the evolution of human traits, among other things.

But it has always been a flawed tool. One of its biggest problems is that about 70 percent of its data came from a single man of predominantly African-European background whose DNA was sequenced during the Human Genome Project, the first effort to capture all of a person's DNA. As a result, it can tell us little about the 0.2 to one percent of genetic sequence that makes each of the seven billion people on this planet different from each other, creating an inherent bias in biomedical data believed to be responsible for some of the health disparities affecting patients today. Many genetic variants found in non-European populations, for instance, aren't represented in the reference genome at all.

For years, researchers have called for a resource more inclusive of human diversity with which to diagnose diseases and guide medical treatments. Now scientists with the Human Pangenome Reference Consortium have made groundbreaking progress in characterizing the fraction of human DNA that varies between individuals. As they recently published in Nature, they've assembled genomic sequences of 47 people from around the world into a so-called pangenome in which more than 99 percent of each sequence is rendered with high accuracy.

Layered upon each other, these sequences revealed nearly 120 million DNA base pairs that were previously unseen.

While it's still a work in progress, the pangenome is public and can be used by scientists around the world as a new standard human genome reference, says The Rockefeller University's Erich D. Jarvis, one of the primary investigators.

"This complex genomic collection represents significantly more accurate human genetic diversity than has ever been captured before," he says. "With a greater breadth and depth of genetic data at their disposal, and greater quality of genome assemblies, researchers can refine their understanding of the link between genes and disease traits, and accelerate clinical research."

Sourcing diversity

Completed in 2003, the first draft of the human genome was relatively imprecise, but it became sharper over the years thanks to filled-in gaps, corrected errors, and advancing sequencing technology. Another milestone was reached last year, when the final eight percent of the genome -- mainly tightly coiled DNA that doesn't code for protein and repetitive DNA regions -- was finally sequenced.

Despite this progress, the reference genome remained imperfect, especially with respect to the critical 0.2 to one percent of DNA representing diversity. The Human Pangenome Reference Consortium (HPRC), a government-funded collaboration between more than a dozen research institutions in the United States and Europe, was launched in 2019 to address this problem.

At the time, Jarvis, one of the consortium's leaders, was honing advanced sequencing and computational methods through the Vertebrate Genomes Project, which aims to sequence all 70,000 vertebrate species. His and other collaborating labs decided to apply these advances for high-quality diploid genome assemblies to revealing the variation within a single vertebrate: Homo sapiens.

To collect a diversity of samples, the researchers turned to the 1000 Genomes Project, a public database of sequenced human genomes that includes more than 2500 individuals representing 26 geographically and ethnically varied populations. Most of the samples come from Africa, home to the planet's largest human diversity.

"In many other large human genome diversity projects, the scientists selected mostly European samples," Jarvis says. "We made a purposeful effort to do the opposite. We were trying to counteract the biases of the past."

It's likely that gene variants that could inform our knowledge of both common and rare diseases can be found among these populations.

Mom, dad, and child

But to broaden the gene pool, the researchers had to create crisper, clearer sequences of each individual-and the approaches developed by members of the Vertebrate Genome Project and associated consortiums were used to solve a longstanding technical problem in the field.

Every person inherits one genome from each parent, which is how we end up with two copies of every chromosome, giving us what's known as a diploid genome. And when a person's genome is sequenced, teasing apart parental DNA can be challenging. Older techniques and algorithms have routinely made errors when merging parental genetic data for an individual, resulting in a cloudy view. "The differences between mom's and dad's chromosomes are bigger than most people realize," Jarvis says. "Mom may have 20 copies of a gene and dad only two."

With so many genomes represented in a pangenome, that cloudiness threatened to develop into a thunderstorm of confusion. So the HPRC homed in a method developed by Adam Phillippy and Sergey Koren at the National Institutes of Health on parent-child "trios" -- a mother, a father, and a child whose genomes had all been sequenced. Using the data from mom and dad, they were able to clear up the lines of inheritance and arrive at a higher-quality sequence for the child, which they then used for pangenome analysis.

New variations

The researchers' analysis of 47 people yielded 94 distinct genome sequences, two for each set of chromosomes, plus the sex Y chromosome in males.

They then used advanced computational techniques to align and layer the 94 sequences. Of the 120 million DNA base pairs that were previously unseen or in a different location than they were noted to be in the previous reference, about 90 million derive from structural variations, which are differences in people's DNA that arise when chunks of chromosomes are rearranged -- moved, deleted, inverted, or with extra copies from duplications.

It's an important discovery, Jarvis notes, because studies in recent years have established that structural variants play a major role in human health, as well as in population-specific diversity. "They can have dramatic effects on trait differences, disease, and gene function," he says. "With so many new ones identified, there's going to be a lot of new discoveries that weren't possible before."

Filling gaps

The pangenome assembly also fills in gaps that were due to repetitive sequences or duplicated genes. One example is the major histocompatibility complex (MHC), a cluster of genes that code proteins on the surface of cells that help the immune system recognize antigens, such as those from the SARS-CoV-2 virus.

"They're really important, but it was impossible to study MHC diversity using the older sequencing methods," Jarvis says. "We're seeing much greater diversity than we expected. This new information will help us understand how immune responses against specific pathogens vary among people." It could also lead to better methods to match organ transplant donors with and patients, or identify people at risk for developing autoimmune disease.

The team has also uncovered surprising new characteristics of centromeres, which lie at the cruxes of chromosomes and conduct cell division, pulling apart as cells duplicate. Mutations in centromeres can lead to cancers and other diseases.

Despite having highly repetitive DNA sequences, "centromeres are so diverse from one haplotype to another, that they can account for more than 50 percent of the genetic differences between people or maternal and paternal haplotypes even within one individual," Jarvis says. "The centromeres seem to be one of the most rapidly evolving parts of the chromosome."

Relationship building

The current 47-people pangenome is just a starting point, however. The HPRC's ultimate goal is to produce high-quality, nearly error-free genomes from at least 350 individuals from diverse populations by mid-2024, a milestone that would make it possible to capture rare alleles that confer important adaptive traits. Tibetans, for example, have alleles related to oxygen use and UV light exposure that enable them to live at high altitudes.

A major challenge in collecting this data will be to gain trust from communities that have seen past abuses of biological data; for example, there are no samples in the current study from Native American nor Aboriginal peoples, who have been long been disregarded or exploited by scientific studies. But you don't have to go far back in time to find examples of unethical use of genetic data: Just a few years ago, DNA samples from thousands of Africans in multiple countries were commercialized without the donors' knowledge, consent, or benefit.

These offenses have sown mistrust against scientists among many populations. But by not being included, some of these groups could remain genetically obscure, leading to a perpetuation of the biases in the data -- and to continued disparities in health outcomes.

Read more at Science Daily

For birds, blending in may result in more diversity

The saying "Birds of a feather flock together" is being given new meaning by a study published in the Philosophical Transactions of the Royal Society b. Flocking birds often travel in groups made up of a single species, in which individuals are nearly indistinguishable from one another, as noted by the proverbial adage. But something strange happens in flocks of two or more species from Southeast Asia. Even when flock species are distantly related, they still seem to converge on the same appearance, as if trying to fit in.

"They all share haphazard traits, like crests or yellow bellies, which makes them almost identical. You can't really tell them apart without looking at their markings," said study co-author Scott Robinson, Ordway eminent scholar at the Florida Museum of Natural History.

According to Robinson, this similarity in plumage is likely a type of mimicry, which by itself isn't uncommon in birds. Alfred Russel Wallace, the co-discoverer of natural selection, was the first to suggest that some bird species engage in mimicry when noting the similarities between orioles and friarbirds in Australia. Birds can mimic one another to reduce aggression from a dominant species; to resemble a more formidable adversary to predators; and, in at least one case, to make themselves appear toxic.

But resemblance in multispecies flocks is something different, said lead author Rebecca Kimball, professor of biology at the University of Florida.

"In mimicry, you often want to look like something because there's an advantage to being that other thing. You want species to think you're toxic or low-profitable prey," she said. "In flocking birds, one idea is that this has more to do with a predator's ability to isolate a target. When there are a bunch of birds moving around, it may be easier for predators to identify an individual that has a distinct color pattern."

This idea that unrelated birds find safety in collective obscurity was first proposed in the 1960s for flocks along the Andes Mountains. But follow-up studies failed to show conclusive evidence of mimicry in Andean multispecies flocks, and the theory was largely abandoned.

"The idea sat fallow for a long time," Robinson said. But in 2010, Robinson began working with a Chinese colleague in Yunnan province and observed what appeared to be the same phenomenon that had been described decades earlier.

Robinson and his colleagues spent the next several years documenting similarities in China's multispecies flocks, uncovering the same pattern again and again. While some of the similarities between species are subtle, the authors points to several visually conspicuous examples.

In western Asia, Himalayan cutias (Cutia nipalensis) look like they're dressed in mismatched layers, with a mask of black feathers, chestnut wings, and white chests with zebra stripes. This pattern might seem impervious to emulation, yet the rufous-backed sibias (Leioptila annectens) they flock with do a remarkably good impression. Both species have similar behavior, foraging patterns and markings, with the exception of stripes, which the sibias lack.

Some birds also seem capable of mimicking more than one species as they mature. Juvenile white-hooded babblers (Gampsorhynchus rufulus) have rusty head feathers, brown wings and creamy underbellies, similar to the parrotbills they flock with. Adults look like an entirely different species, with white heads and dark brown wings that resemble white-crested laughingthrushes (Garrulax leucolophus), all of which are part of the same flock.

Somewhat counterintuitively, this conformity within multispecies flocks may be contributing to diversity in the region. Not only can birds mimic more than one species at different stages of development, but their appearance can also vary across their range. In eastern China, coal tits tag along with birds with prominent crest feathers, which they mimic. In the Himalayas and Hengduan Mountains farther west, the same species lacks a crest and flocks with other crestless birds.

If these differences persist long enough, Robinson said, it might ultimately result in one species becoming two. "The possible role this type of mimicry plays in speciation is the most interesting idea from our point of view. Many of these birds have huge ranges, and there may be a lot of differentiation in these traits involved in flocking within a species."

There seem to be two main ingredients required to create this type of mimicry in flocks, both of which might help explain why this pattern appears to be so prominent in China but absent elsewhere.

First, Robinson said, a flock must be composed of just a few species, with some more common than others. "When you have a flock with a really dominant, abundant species, there's a model worth mimicking. If other birds look like that model, they get the same protection, they get access to the same resources, and they get to travel with a compatible group."

In other parts of the world, many flocks have more of an open-door policy, weakening the selective forces that contribute to mimicry. Mating pairs of multiple species join together in patchwork groups, often relying on the warning calls of sentries to avoid predators rather than their ability to fade into the background.

The second ingredient is the winnowing fan of predation. For small to medium flocking birds, the biggest source of danger comes from above, in the form of raptors, and the skies above Southeast Asia are especially fraught. The region encompasses only 3% of Earth's land area, yet it harbors almost 30% of all raptor species. This puts an enormous amount of pressure on flocks, Robinson said, which may promote mimicry.

To determine whether similarity among flocking species is the result of mimicry, the authors say they'll need to conduct widescale genetic analyses to rule out other potential causes.

Read more at Science Daily

Grambank shows the diversity of the world's languages

Linguists have long been interested in language variation. What are common or universal patterns across languages? What limits the possible variation between them? Grambank, the world's largest and most comprehensive database of language structure, enables researchers to answer some of these questions.

Grambank was constructed in an international collaboration between the Max Planck institutes in Leipzig and Nijmegen, the Australian National University, the University of Auckland, Harvard University, Yale University, the University of Turku, Kiel University, Uppsala University, SOAS, the Endangered Languages Documentation Programme, and over a hundred scholars from around the world. Grambank's coverage spans 215 different language families and 101 isolates from all inhabited continents. "The design of the feature questionnaire initially required numerous revisions in order to encompass many of the diverse solutions that languages have evolved to code grammatical properties," says Hedvig Skirgård, who coordinated much of the coding and is the lead author of the study.

Limits on variation

The team settled on 195 grammatical properties, ranging from word order to whether or not a language has gendered pronouns. For instance, many languages have separate pronouns for 'he' and 'she', but some also have male and female versions of 'I' or 'you'. The possible 'design space' would be enormous if grammatical properties were to vary freely. Limits on variation could be related to cognitive principles rooted in memory or learning, rendering some grammatical structures more likely than others. Limits could also be related to historical 'accidents', such as descent from a common language or contact with other languages.

The researchers discovered much greater flexibility in the combination of grammatical features than many theorists have assumed. "Languages are free to vary considerably in quantifiable ways, but not without limits," explains Stephen Levinson, Director emeritus of the Max Planck Institute for Psycholinguistics in Nijmegen and one of the founders of the Grambank project. "A sign of the extraordinary diversity of the 2400 languages in our sample is that only five of them occupy the same location in design space (share the same grammatical properties)."

Languages show much greater similarity to those with a common ancestor than those they are in contact with. "Genealogy generally trumps geography," says Russell Gray, Director of the Department of Linguistic and Cultural Evolution and senior author of the study. "Nevertheless, if processes of linguistic evolution and diversification were run again from the beginning, there would still be some resemblance to what we now have. The constraints of human cognition mean that, while there is a great deal of historical contingency in the organisation of grammatical structures, there are regular patterns as well."

Diversity under threat

"The extraordinary diversity of languages is one of humanity's greatest cultural endowments," concludes Levinson. "This endowment is under threat, especially in some areas such as Northern Australia, and parts of South and Northern America. Without sustained efforts to document and revitalise endangered languages, our linguistic window into human history, cognition and culture will be seriously fragmented."

Read more at Science Daily

Thousands of native plants are unphotographed, and citizen scientists can help fill the gaps

Scientists have documented plant species for centuries to help us understand and protect the incredible diversity of flora in our world. But according to new research, many have never actually been photographed in their natural habitats -- and that's a problem.

Researchers from UNSW Sydney and the Australian Institute of Botanical Science, part of the Royal Botanic Gardens and Domain Trust, surveyed 33 major online databases of plant photographs to examine the photographic record of Australian plant species. The findings, published in New Phytologist, reveal out of 21,077 native Australian vascular plant species, almost 20 per cent lack a verifiable photograph.

Lead author of the study and UNSW Science PhD student Thomas Mesaglio says Australia is one of the richest areas in the world for native species.

"It was surprising to see how many plant species had just line drawings, illustrations, paintings, or even no media at all," Mr Mesaglio says.

Dr Hervé Sauquet, co-author of the study and Senior Research Scientist at the Australian Institute of Botanical Science, is based at the National Herbarium of New South Wales.

"All species of plants ultimately rely on specimens in herbarium collections for their identification," Dr Sauquet says. "Yet, even in this digital age where most herbarium specimens have been scanned and are accessible on the web, photos of live plants in the wild remain in critical need."

Senior author of the study from UNSW Science Associate Professor Will Cornwell says a lack of detailed photos can have real consequences. Many plant species that are difficult to identify in the wild may go extinct if scientists cannot properly identify them with the help of photos.

"We had assumed every plant species would have simply been photographed by someone, somewhere, throughout history. But it turns out this isn't the case," says A/Prof. Cornwell.

"This is where citizen scientists can come in and help us fill this gap with their photos."

Gaps in the photographic record

Photographs can help botanists and taxonomists who work with plant specimens by preserving characteristics like flower colour that get lost over time in their samples. They can also show additional features, such as the orientation of leaves or bark appearance, and add ecological context.

"Having a comprehensive photographic set helps us to be confident in our identifications," Mr Mesaglio says. "Particularly when it is practically challenging to collect and preserve the entire plant, photos complement the physical voucher by showing the soil type, the habitat it's growing in, and other species growing alongside it."

But it turns out not all plant groups are photographed equally. Just as some animals receive less attention than others, there might also be a bias against less charismatic plants.

The study found the most well-photographed plant groups tend to be shrubs or trees with more noticeable or spectacular features, such as colourful flowers. Banksia, for example, is one of only two Australian plant genera with more than 40 species to have a complete photographic record. Meanwhile, the family with the most significant photo deficit was Poaceae -- commonly known as grasses -- with 343 unphotographed species.

"We noticed a charisma deficit, so the species that tend to be harder to see are the ones missing out," Mr Mesaglio says. "They may have innocuous or pale-looking flowers or be smaller and harder to spot grasses, sedges and herbs."

Geography also affected the photographic record. While most species across the south-eastern states of Australia have comprehensive records, Western Australia had the largest void, with 52 per cent of all unphotographed species found there.

"The primary 'hotspots' for unphotographed Australian plants are areas with high plant diversity, but the environments are rugged and often difficult to access, particularly by road," Mr Mesaglio says. "But it means there's an exciting opportunity to visit these locations because we might capture something that has never before been photographed."

Activating citizen scientist snaps

It's one thing to have comprehensive photographic records for professional scientists to use in identification guides. But when the plant world is under threat from multiple fronts, including habitat clearing and climate change, photos can help engage the public in plant science.

"People can engage with, sympathise with, and get much more excited about plants with photographs, which is vital when our natural environments are more at risk than ever," Mr Mesaglio says.

"Because digital photography is so accessible now, anyone can also help make a meaningful contribution to science using the camera in their pocket."

Using a platform like iNaturalist, keen citizen scientists can have their snaps identified by experts and share the data with aggregators like the Atlas of Living Australia and the Global Biodiversity Information Facility to be used in research and conservation.

"Since April last year, we've identified nearly 10 per cent of those previously unphotographed species thanks to members of the public uploading their photographs and experts who've kindly identified them," Mr Mesaglio says. "There could be many more in personal collections or behind paywalls just waiting to be shared."

The researchers recommend a standardised system for scientific plant photography be developed, starting with a requirement in the International Code of Nomenclature for Plants to include at least one field photograph where possible in new species descriptions. They also suggest all new species descriptions be published as Open Access in searchable databases with Creative Commons licensing to maximise their usage.

"We also suspect more photos exist, but they're hidden away on social media or behind scientific paywalls that aren't accessible, discoverable, or searchable," Mr Mesaglio says.

Read more at Science Daily

Mulching time of forest meadows influences insect diversity

Mulching is a possible management method for forest meadows and is important to their upkeep. During the process, the meadow is cut and the cuttings are shredded and left on the meadow. Despite its significance, the effects of this method on insects living in this habitat has rarely been studied up to now. Dr. Maria M. Georgi of the team working with the head of the University of Freiburg's Chair of Nature Conservation and Landscape Ecology -- Prof. Dr. Alexandra-Maria Klein, and her colleagues studied this in-depth. The result: Nearly all the mulching times examined had a negative impact on insect larvae and flower-visiting insects which are found on forest meadows. Georgi says, "Management is important for the maintenance of forest meadows. That is why we're proposing alternative types of mulching be applied in future to improve conservation of the insects living there if no opportunity to apply another method, such as cut, is available."

Meadows are important to the forest; mulching is important to the meadows

Forest meadows are often managed to attract game animals. This reduces their browsing of young plants -- so the grazing of leaves and twigs -- in the surrounding woods. Management is required to retain forest meadows. Otherwise, the forest would spread increasingly and the meadow would disappear. Compared to other methods, mulching is more effective in terms of cost and labor intensity. During the processes the meadow is mowed and the cuttings are shredded and left on the meadow. Although the impact of cut on plant and insect diversity has been intensively investigated, the opposite had been the case for mulching up to now.

Examining of four mulching times

The study was carried out at 24 locations in the northern Black Forest. The focus was on insect larvae and insect flower-visitors. The researchers examined how different mulching times affected these insects. Six locations were designated for a control group. They were not mulched. These were compared with six meadows that were mulched either in June or September, as well as six additional meadows that were mulched both in June and September. In terms of insect larvae, sawflies (Symphyta) accounted for 45 percent of the population studied, with butterflies (Lepidoptera) making up 44 percent. Hover files (Syrphidae) dominated the flower-visiting insects. They made up a share of 80 percent.

September mulching protects flower-visiting insects

For the insect larvae, all three mulching times studied had a negative impact on numbers compared to the control group. The findings were similar for the flower-visiting insects. Here, mulching in June, as well as mulching in June and September, had a negative impact on the number of insects counted. Yet September mulching had no impact in the case of flower-visitors. Georgi concludes, "On the basis of our results, we can recommend mulching in September in order to protect flower-visitors."

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Wide diversity of galaxies in the early universe

New data from the James Webb Space Telescope (JWST) have revealed that the structures of galaxies in the early universe were much more diverse and mature than previously known. Scientists compared images of hundreds of galaxies taken by JWST for the Cosmic Evolution Early Release Science (CEERS) Survey with corresponding images previously taken by the Hubble Space Telescope and presented the results at the 241st meeting of the American Astronomical Society.

The study examined 850 galaxies at redshifts of z three through nine, or as they were roughly 11-13 billion years ago. Associate Professor Jeyhan Kartaltepe from Rochester Institute of Technology's School of Physics and Astronomy said that JWST's ability to see faint high redshift galaxies in sharper detail than Hubble allowed the team of researchers to resolve more features and see a wide mix of galaxies, including many with mature features such as disks and spheroidal components.

"There have been previous studies emphasizing that we see a lot of galaxies with disks at high redshift, which is true, but in this study we also see a lot of galaxies with other structures, such as spheroids and irregular shapes, as we do at lower redshifts," said Kartaltepe, lead author on the paper and CEERS co-investigator. "This means that even at these high redshifts, galaxies were already fairly evolved and had a wide range of structures."

The results of the study, which have been posted to ArXiv and accepted for publication in The Astrophysical Journal, demonstrate JWST's advances in depth, resolution, and wavelength coverage compared to Hubble. Out of the 850 galaxies used in the study that were previously identified by Hubble, 488 were reclassified with different morphologies after being shown in more detail with JWST. Kartaltepe said scientists are just beginning to reap the benefits of JWST's impressive capabilities and are excited by what forthcoming data will reveal.

"This tells us that we don't yet know when the earliest galaxy structures formed," said Kartaltepe. "We're not yet seeing the very first galaxies with disks. We'll have to examine a lot more galaxies at even higher redshifts to really quantify at what point in time features like disks were able to form."

The study used an initial data set captured by CEERS when JWST first came online in June, but the survey has since captured a total of 60 observing hours, potentially providing thousands of high redshift galaxies to further explore. Kartaltepe said COSMOS-Web, the largest General Observer program selected for JWST's first year, will provide an even larger sample through 255 hours of observing time with the telescope. COSMOS-Web began its observing campaign this month.

Read more at Science Daily

Less intensively managed grasslands have higher plant diversity and better soil health

Researchers have shown -- for the first time -- that less intensively managed British grazed grasslands have on average 50% more plant species and better soil health than intensively managed grassland. The new study could help farmers increase both biodiversity and soil health, including the amount of carbon in the soil of the British countryside.

Grazed grassland makes up a large proportion of the British countryside and is vital to farming and rural communities. This land can be perceived as only being about food production, but this study gives more evidence that it could be key to increasing biodiversity and soil health.

Researchers at the UK Centre for Ecology & Hydrology (UKCEH) studied 940 plots of grassland, comparing randomly selected plots which sampled the range of grassland management across Great Britain; from intensively- managed land with a few sown grassland species and high levels of soil phosphorus (indicating ploughing/reseeding and fertiliser and slurry application), to grassland with higher levels of species and lower levels of soil phosphorus. The plots were sampled as part of the UKCEH Countryside Survey, a nationally representative long-term dataset.

The study counted the number of plant species in sample areas and analysed co-located soil samples for numbers of soil invertebrates and carbon, nitrogen and phosphorus levels.

Researchers found that less intensively managed grassland had greater diversity of plant species and, strikingly, this correlated with better soil health, such as increased nitrogen and carbon levels and increased numbers of soil invertebrates such as springtails and mites.

In the same study, the researchers used the same methods to examine the plant diversity and soil from grasslands on 56 mostly beef farms from the Pasture Fed Livestock Association (PFLA) -- a farmer group that has developed standards to manage and improve soil and pasture health.

The researchers found that plots of land from PFLA farms had greater plant diversity -- on average an additional six plant species, including different types of grasses and herbaceous flowering plants, compared to intensively farmed plots from the Countryside Survey. In addition, grassland plants on these farms were often taller, a quality which is proven to be beneficial to butterflies and bees.

Pasture Fed Livestock Association grasslands did not yet show increased soil health, but the research indicated that this may be due to a time lag between increasing numbers of plant species and changes in soil health, particularly on farms which have been intensively managed in the past.

Lead author Dr Lisa Norton, Senior Scientist at UKCEH, says: "We've shown for the first time, on land managed by farmers for production, that a higher diversity of plants in grasslands is correlated with better soil health. This work also tells us that the Pasture Fed Livestock Association members are on the right track to increase biodiversity, though it may take longer to see improvements in soil health.

"Grassland with different types of plants able to grow tall and flower is associated with improved soil health measures, and is beneficial for creepy crawlies below and above ground. Having this abundance of life in our grasslands can in turn support small mammals and birds of prey, and farmers have told us that they are seeing voles and mice in their fields for the first time."

Dr Norton adds: "My hope for the future is that our grasslands can be managed less intensively -- with all the improvements in plant and animal biodiversity and soil health that brings -- but still remain productive for farmers."

Read more at Science Daily

New global map of ant biodiversity reveals areas that may hide undiscovered species

They are hunters, farmers, harvesters, gliders, herders, weavers, and carpenters. They are ants, and they are a big part of our world, comprising over 14,000 species and a large fraction of animal biomass in most terrestrial ecosystems. Like other invertebrates, ants are important for the functioning of ecosystems. They play vital roles from aerating soil and dispersing seeds and nutrients, to scavenging and preying on other species. Yet a global view of their diversity is lacking. Now, researchers from the Biodiversity and Biocomplexity Unit at the Okinawa Institute of Science and Technology (OIST), in collaboration with multiple institutes around the world, have developed a high-resolution map that combines existing knowledge with machine learning to estimate and visualize the global diversity of ants. The maps and dataset were published in an article in Science Advances.

"This study helps to add ants, and terrestrial invertebrates in general, to the discussion on biodiversity conservation," said Prof. Evan Economo, who leads the Biodiversity and Biocomplexity Unit. "We need to know the locations of high diversity centers of invertebrates so that we know the areas that can be the focus of future research and environmental protection."

Prof. Economo added that the resource will also serve to answer a number of biological and evolutionary questions, such as how life diversified and how patterns in diversity arose.

This decade-long project began when study co-first author and former OIST postdoc Dr. Benoit Guénard (now at The University of Hong Kong), worked with Prof. Economo to create a database of occurrence records for different ant species from online repositories, museum collections, and around 10,000 scientific publications. Researchers around the world contributed and helped identify errors. More than 14,000 species were considered, which varied dramatically in the amount of data available.

However, the vast majority of these records, while containing a description of the sampled location, did not have the precise coordinates needed for mapping. To address this, coauthor Kenneth Dudley from OIST's Environmental Informatics Section built a computational workflow to estimate the coordinates from the available data, which also checked all the data for errors.

Then JSPS Postdoctoral Researcher and co-first author Dr. Jamie Kass, with Dudley and research technician Fumika Azuma, made different range estimates for each species of ant depending on how much data was available. For species with less data, they constructed shapes surrounding the data points. For species with more data, the researchers predicted the distribution of each species using statistical models that they tuned for optimal complexity.

The researchers brought these estimates together to form a global map, divided into a grid of 20 km by 20 km squares, that showed an estimate of the number of ant species per square (called the species richness). They also created a map that showed the number of ant species with very small ranges per square (called the species rarity). In general, species with small ranges are particularly vulnerable to environmental changes.

However, there was another problem to overcome -- sampling bias. "Some areas of the world that we expected to be centers of diversity were not showing up on our map, but ants in these regions were not well-studied," explained Dr. Kass. "Other areas were extremely well-sampled, for example parts of the USA and Europe, and this difference in sampling can impact our estimates of global diversity."

So, the researchers utilized machine learning to predict how their diversity would change if they sampled all areas around the world equally, and in doing so, identified areas where they estimate many unknown, unsampled species exist. Prof. Economo said, "This gives us a kind of 'treasure map', which can guide us to where we should explore next and look for new species with restricted ranges."

Okinawa, in southern Japan, was identified as a center for rarity, as many species endemic to these islands have very small ranges, around 1000 times smaller than species spread across North America and Europe. Thus, places like Okinawa are critical for environmental protection to conserve biodiversity.

When the researchers compared the rarity and richness of ant distributions to the comparatively well-studied amphibians, birds, mammals, and reptiles, they found that ants were about as different from these vertebrate groups as the vertebrate groups were from each other, which was unexpected given that ants are evolutionarily highly distant from vertebrates. This is important as it suggests that priority areas for vertebrate diversity may also have a high diversity of invertebrate species. But, at the same time, it is necessary to recognize that ant biodiversity patterns do have unique features. For example, the Mediterranean and East Asia show up as diversity centers for ants more than the vertebrates.

Finally, the researchers looked at how well-protected these areas of high ant diversity are. They found that it was a low percentage -- only 15% of the top 10% of ant rarity centers had some sort of legal protection, such as a national park or reserve, which is less than existing protection for vertebrates.

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A family of termites has been traversing the world's oceans for millions of years

Termites are a type of cockroach that split from other cockroaches around 150 million years ago and evolved to live socially in colonies. Today, there are many different kinds of termites. Some form large colonies with millions of individuals, which tend to live in connected tunnels in the soil. Others, including most species known as drywood termites, form much smaller colonies of less than 5000 individuals, and live primarily in wood.

Researchers from the Evolutionary Genomics Unit at the Okinawa Institute of Science and Technology Graduate University (OIST), alongside a network of collaborators from across the world, have mapped out the natural history of drywood termites -- the second largest family of termites -- and revealed a number of oceanic voyages that accelerated the evolution of their diversity. The research, published in Molecular Biology and Evolution, shines light on where termites originated and how and when they spread across the globe. It also confirms that some species have, in recent centuries, hitched a ride with humans to reach far-flung islands.

"Drywood termites, or Kalotermitidae, are often thought of as primitive because they split from other termites quite early, around 100 million years ago, and because they appear to form smaller colonies," said Dr. Aleš Buček, OIST Postdoctoral Researcher and lead author of the study. "But very little is actually known about this family."

Dr. Buček went on to explain how, before this study, there was very little molecular data on the family and the little understanding of the relationships between the different species that was known was based on their appearance. Previous research had focused on one genus within the family that contains common pest species, often found within houses.

To gain overarching knowledge, the researchers collected hundreds of drywood termite samples from around the world over a timespan of three decades. From this collection, they selected about 120 species, some of which were represented by multiple samples collected in different locations. This represented over a quarter of Kalotermitidae diversity. Most of these samples were brought to OIST where the DNA was isolated and sequenced.

By comparing the genetic sequences from the different species, the researchers constructed an extensive family tree of the drywood termites.

They found that drywood termites have made more oceanic voyages than any other family of termites. They've crossed oceans at least 40 times in the past 50 million years, travelling as far as South America to Africa, which, over a timescale of millions of years, resulted in the diversification of new drywood termite species in the newly colonized places.

"They're very good at getting across oceans," said Dr. Buček. "Their homes are made of wood so can act as tiny ships."

The researchers found that most of the genera originated in southern America and dispersed from there. It takes a scale of millions of years for one species to split into several after a move. The research also confirmed that, more recently, dispersals have largely been mediated by humans.

Furthermore, this study has cast doubt on the common assumption that drywood termites have a primitive lifestyle. Among the oldest lineages in the family, there are termite species that do not have a primitive lifestyle. In fact, they can form large colonies across multiple pieces of wood that are connected by tunnels underground.

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First animals developed complex ecosystems before the Cambrian explosion

Early animals formed complex ecological communities more than 550 million years ago, setting the evolutionary stage for the Cambrian explosion, according to a study by Rebecca Eden, Emily Mitchell, and colleagues at the University of Cambridge, UK, publishing May 17 in the open-access journal PLOS Biology.

The first animals evolved towards the end of the Ediacaran period, around 580 million years ago. However, the fossil record shows that after an initial boom, diversity declined in the run-up to the dramatic burgeoning of biodiversity in the so-called "Cambrian explosion" nearly 40 million years later. Scientists have suggested this drop in diversity is evidence of a mass extinction event roughly 550 million years ago -- possibly caused by an environmental catastrophe -- but previous research has not investigated the structure of these ancient ecological communities.

To evaluate the evidence for an Ediacaran mass extinction, researchers analyzed the metacommunity structure of three fossil assemblages that span the last 32 million years of this geological period (between 575 to 543 million years ago). They used published paleoenvironmental data, such as ocean depth and rock characteristics, to look for metacommunity structure indicative of environmental specialization and interactions between species. The analysis revealed increasingly complex community structure in the later fossil assemblages, suggesting that species were becoming more specialized and engaging in more inter-species interactions towards the end of the Ediacaran era, a trend often seen during ecological succession.

The results point to competitive exclusion, rather than mass extinction, as the cause of the diversity drop in the late Ediacaran period, the authors say. The analysis indicates that the features of ecological and evolutionary dynamics commonly associated with the Cambrian explosion -- such as specialization and niche contraction -- were established by the first animal communities in the late Ediacaran.

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