Wastewater pipe dig reveals 'fossil treasure trove'

A new New Zealand Journal of Geology and Geophysics paper out today describes the 266 fossil species as one of the richest and most diverse groups of three-million-year-old fauna ever found in New Zealand. At least ten previously unknown species will be described and named in future research.

Fossil treasure trove from Auckland's Mangere Wastewater Treatment Plant

In 2020, when Auckland's Watercare were excavating two huge vertical shafts for a major upgrade of the major pipeline that brings raw sewage for treatment from the central city they dug through an ancient shell bed. Auckland paleontologist Bruce Hayward likened it to "finding gold right on your door step." Once they were informed of the fossil deposit's significance, Watercare and their contractors were eager to help and a huge heap of shelly sand was dumped in a nearby paddock so that paleontologists could search through it over many months. Watercare also funded two paleontology graduate students, working under the supervision of Auckland Museum curator Dr Wilma Blom, to painstakingly sift through the heap for many weeks. As a result, it is estimated that over 300,000 fossils were examined and several thousand have been returned in the museum as a record of this "once-in-a-lifetime find."

"Detailed identification of the fossils shows that they were deposited between 3 and 3.7 million years ago in a subtidal channel in an early version of the modern Manukau Harbour," said Dr Hayward. "At that time, sea level was slightly higher than it is today as the world was also several degrees warmer than now. As a result, the fossils include a number of subtropical species, whose relatives today live in the warmer waters around the Kermadec and Norfolk islands. At least ten previously unknown species are present and will be described and named in future work."

In their scientific paper that appeared this week in the New Zealand Journal of Geology and Geophysics, the five authors record 266 different fossil species, making it the richest and most diverse fauna of its age ever found in New Zealand. "What is surprising," says lead author Dr Hayward "is that the fauna contains fossils that lived in many different environments that have been brought together in the ancient marine channel by wave action and strong tidal currents. It includes ten specimens of the iconic NZ flax snail that must have lived on the adjacent land and been washed down into the sea by storm runoff. These are by far the oldest known flax snails in the world. Most of the fossils lived on the sea floor, some in brackish estuaries, others attached to hard rocky shorelines and still more have been carried in from offshore of the exposed west coast at the time."

Read more at Science Daily

Case study of rare, endangered tortoise highlights conservation priorities for present, future World Wildlife Days

Though wildlife trafficking has been effectively disrupted since the first World Wildlife Day -- established 50 years ago today via the 1973 Convention on International Trade in Endangered Species (CITES) of Wild Fauna and Flora -- a newly published case study on one of the world's rarest tortoise species, the ploughshare tortoise, highlights how much room for improvement still exists.

In a new paper published in the Proceedings of the National Academies of the Sciences, University of Maryland Associate Professor Meredith Gore and her coauthors -- Babson College's Emily Griffin, Bistra Dilkina and Aaron Ferber from the University of Southern California, Michigan State University's Stanley E. Griffis, the University of Alabama's Burcu B. Keskin, and John Macdonald from Colorado State University -- detail a 2018 effort to map ploughshare tortoises' location within and around Soalala, Madagascar; nearby villages; known trafficking pathways and transit routes; and the amount of trafficking risk associated with each of those areas. The group of approximately 50 stakeholders also shared more qualitative information that might play a role in poachers' trafficking process, such as paths of cultural and spiritual significance, tides' influence on decision-making; and where poachers met to plan their activities.

This information was drawn onto a clear, plastic sheet that was laid across a color-based map of the region. That information was then digitized into a geographic information system, creating what the researchers' called a "mess" that nevertheless revealed novel information for the effective targeting of those ploughshare tortoise trafficking networks.

"Our science team used a cross-disciplinary and cross-sectoral approach to think about, measure, and analyze data," explains Gore. "Not only were we able to shift the data landscape to clarify how important water routes are to the resilience of the illicit supply chain, we were able to normalize technical spatial data with insights from traditionally marginalized voices -- women."

Gore and her co-authors argue that if a process like this were to be paired with the latest advancements in computational science, operations engineering, and supply chain management, together, researchers could dramatically disrupt wildlife trafficking networks, and thereby conserve more animals, like the ploughshare tortoise, who are already on the brink of extinction.

"As we celebrate World Wildlife Day, our recent work highlights the urgent need for interdisciplinary collaboration to address the complex global issue of wildlife trafficking," says Bistra Dilkina, an associate professor of computer science and industrial and systems engineering at the University of Southern California. "I feel privileged to have the opportunity to work with a trans-disciplinary team to synthesize a roadmap of how our different disciplines can work together to fight illegal wildlife trafficking and trade. In particular, I am excited to think deeply about the advantages that data-driven approaches in machine learning and optimization can bring to this important endeavor."

Looking to the future, the researchers believe that with increased interdisciplinary collaborations, conservationists may one day be able to predict which path a trafficker will take, target areas where locals could undergo trainings and be empowered to play a part in preventing wildlife trafficking, better allocate limited resources to have the greatest interventional impact, and more.

Read more at Science Daily

Siberian tundra could virtually disappear by mid-millennium

Due to global warming, temperatures in the Arctic are climbing rapidly. As a result, the treeline for Siberian larch forests is steadily advancing to the north, gradually supplanting the broad expanses of tundra which are home to a unique mix of flora and fauna. Experts from the Alfred Wegener Institute have now prepared a computer simulation of how these woods could spread in the future, at the tundra's expense. Their conclusion: only consistent climate protection measures will allow roughly 30 percent of the Siberian tundra to survive to mid-millennium. In all other, less favourable scenarios, the unique habitat is projected to disappear entirely. The study was just released in the journal eLife.

The climate crisis can especially be felt in the Arctic: in the High North, the average air temperature has risen by more than two degrees Celsius over the past 50 years -- far more than anywhere else. And this trend will only continue. If ambitious greenhouse-gas reduction measures (Emissions Scenario RCP 2.6) are taken, the further warming of the Arctic through the end of the century could be limited to just below two degrees. According to model-based forecasts, if the emissions remain high (Scenario RCP 8.5), we could see a dramatic rise in the average summer temperatures in the Arctic -- by up to 14 degrees Celsius over today's norm by 2100.

"For the Arctic Ocean and the sea ice, the current and future warming will have serious consequences," says Prof Ulrike Herzschuh, Head of the Polar Terrestrial Environmental Systems Division at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI). "But the environment on land will also change drastically. The broad expanses of tundra in Siberia and North America will be massively reduced, as the treeline, which is already slowly changing, rapidly advances northward in the near future. In the worst-case scenario, there will be virtually no tundra left by the middle of the millennium. In the course of our study, we simulated this process for the tundra in northeast Russia. The central question that concerned us was: which emissions path does humanity have to follow in order to preserve the tundra as a refuge for flora and fauna, as well its role for the cultures of indigenous peoples and their traditional ties to the environment?"

The tundra is home to a unique community of plants, roughly five percent of which are endemic, i.e., can only be found in the Arctic. Typical species include the mountain avens, Arctic poppy and prostrate shrubs like willows and birches, all of which have adapted to the harsh local conditions: brief summers and long, arduous winters. It also offers a home for rare species like reindeer, lemmings and insects like the Arctic bumblebee.

For their simulation, Ulrike Herzschuh and AWI modeller Dr Stefan Kruse employed the AWI vegetation model LAVESI. "What sets LAVESI apart is that it allows us to display the entire treeline at the level of individual trees," Kruse explains. "The model portrays the entire lifecycle of Siberian larches in the transition zone to the tundra -- from seed production and distribution, to germination, to fully grown trees. In this way, we can very realistically depict the advancing treeline in a warming climate."

The findings speak for themselves: the larch forests could spread northward at a rate of up to 30 kilometres per decade. The tundra expanses, which can't shift to colder regions due to the adjacent Arctic Ocean, would increasingly dwindle. Since trees aren't mobile and each one's seeds can only reach a limited distribution radius, initially the vegetation would significantly lag behind the warming, but then catch up to it again. In the majority of scenarios, by mid-millennium less than six percent of today's tundra would remain; saving roughly 30 percent would only be possible with the aid of ambitious greenhouse-gas reduction measures. Otherwise, Siberia's once 4,000-kilometre-long, unbroken tundra belt would shrink to two patches, 2,500 kilometres apart, on the Taimyr Peninsula to the west and Chukotka Peninsula to the east. Interestingly, even if the atmosphere cooled again in the course of the millennium, the forests would not completely release the former tundra areas.

Read more at Science Daily

European earthworms reduce insect populations in North American forests

Earthworms introduced into northern North America have a negative impact on the insect fauna above ground. Soil ecologists found this impact for abundance as well as for biomass and species richness of insects. Their results indicate that changes in insect communities can have causes that have previously received little attention.

At least since the last ice age, about 10,000 years ago, there have been almost no earthworms in the northern part of North America. However, over the last few centuries, they have been introduced, probably through soil and plant transport from Europe. Since then, they have been dispersed and changed the soil significantly, with far-reaching consequences for the soil ecosystem. What impact these invaders have on the world above ground has, up to now, rarely been investigated.

The study was performed in a forest near Calgary in Canada, which has areas that are either inhabited or uninhabited by earthworms. Here, the researchers used insect vacuum samplers to capture aboveground insects and compared the catches. They discovered that the abundance, biomass, and species richness of insects in areas with invasive earthworms, and those areas without them differed significantly. Where earthworm biomass was highest, the number of insect individuals was reduced by 61 per cent, insect biomass by 27 per cent and species richness by 18 per cent.

Insect above ground affected by invasive earthworms underground

"We had expected that earthworms would have an impact on aboveground insects," says lead author Dr Malte Jochum from iDiv and Leipzig University. "Even so, I was surprised at how pronounced the effects were, and that not only the abundance but also biomass and species richness were affected."

The mechanisms by which the earthworms affect the insects are, however, still not clear. "It's possible that the earthworms eat the food and reduce the habitat of those aboveground insects, such as beetles and fly larvae, which break down dead plant material," says Jochum. Since the majority of insects are herbivores, it could also be hypothesised that the observed decline in insects is due to changes in the vegetation caused by altered soil conditions. In this case, however, the researchers were unable to detect any significant alteration in the number of plant species or plant coverage. "Still, this doesn't rule out the influence of the plants," says Jochum. However, the data on species composition and other functional characteristics of the plant communities have yet to be evaluated.

The increase in predatory insect species and spiders was also striking. These seem to be benefiting from the changes.

Underestimated causes for biodiversity loss to be considered in conservation

"Up to now, only a few causes have been used to explain global changes in insect populations; mostly alterations in habitats above the ground," says senior author Prof Nico Eisenhauer from iDiv and Leipzig University. "These new results show that biodiversity loss can also have other causes which have, so far, received little attention and that these should be taken into consideration when developing management and conservation strategies for biodiversity."

Introduced earthworm species are not only found in North America but on almost every continent. However, since there had been very few earthworms in northern North America for a very long time, the effect of these invaders is particularly pronounced. "For regions like Europe, where natural communities have always co-developed with earthworms, comparable negative effects due to new earthworm species are very unlikely," says Jochum. "Quite the opposite. Here they are important ecosystem engineers, which many important ecosystem functions depend on."

Read more at Science Daily

Ancient bones provide clues about Kangaroo Island's past and future

A Curtin University-led study of ancient bones on South Australia's Kangaroo Island has provided new information about the Island's past fauna and an insight into how species may live there in the future.

Published in Quaternary Science Reviews, the researchers analysed around 2,000 bone fragments with the aim of eventually being able to establish a more complete picture of past biodiversity on the Island.

Lead researcher Dr Frederik Seersholm from Curtin's School of Molecular and Life Sciences said DNA studies on such a large scale have never been done on the Island before.

"We identified 33 species, 10 of which are extinct on the island today. We also found DNA traces from both the Eastern and the Western grey kangaroos- which is interesting given it was previously thought that only the Western used to roam the Island," Dr Seersholm said.

"Our research also discovered an extinct population of spotted-tailed quoll, different from both the modern mainland and Tasmanian populations, indicating that it once lived on Kangaroo Island and perhaps other parts of South Australia too.

"While Kangaroo Island is a renowned biodiversity hotspot, and natural haven for several threatened and endemic species, it has been continuously losing species richness since European arrival on the Island 200 years ago.

"From excavations of these ancient fossil bones, we now know more about the species that used to roam the Island before this human-caused decimation."

Dr Seersholm said this research was particularly important in the wake of the major bushfires of 2019/2020 which had a devastating impact on Kangaroo Island's pristine ecosystem.

"We hope our work in accurately identifying species can aid conservation and restoration efforts and help to restore the biodiversity on Kangaroo Island," Dr Seersholm said.

"While more research is needed in this area, our study has confirmed that Kangaroo Island could be a potential haven for the reintroduction of some species.

"If a quoll population should be introduced to the island, it is essential to get a detailed picture of the extinct quoll population. The research has also added the eastern grey kangaroo to the list of potential reintroduction candidates.

Read more at Science Daily