Animal evolution: Hot start, followed by cold shock

Red Sea Sponge.

The initial phases of animal evolution proceeded faster than hitherto supposed: New analyses suggest that the first animal phyla emerged in rapid succession -- prior to the global Ice Age that set in around 700 million years ago.

The fossil record reveals that almost all of the animal phyla known today had come into existence by the beginning of the Cambrian Period some 540 million years ago. The earliest known animal fossils already exhibit complex morphologies, which implies that animals must have originated long before the onset of the Cambrian. However, taxonomically assignable fossils that can be confidently dated to pre-Cambrian times are very rare. In order to determine what the root of their family tree looked like, biologists need reliable dating information for the most ancient animal subgroups -- the sponges, cnidarians, comb jellies and placozoans. Dr. Martin Dohrmann and Professor Gert Wörheide of the Division of Palaeontology and Geobiology in the Department of Earth and Environmental Sciences at Ludwig-Maximilians-Universitaet (LMU) in Munich have now used a new strategy based on the so-called molecular-clock to investigate the chronology of early animal evolution and produce a new estimate for the ages of the oldest animal groups. Their findings appear in the journal Scientific Reports.

The molecular clock approach is based on the principle that mutations accumulate in the genomes of all organisms over the course of time. The extent of the genetic difference between two lineages should therefore depend on the time elapsed since they diverged from their last common ancestor. "Our study is based on a combination of genetic data from contemporary animals and information derived from well dated fossils, which we analyzed with the help of complex computer algorithms," Dohrmann explains. For the study, the researchers used an unusually large dataset made up of the sequences of 128 proteins from 55 species, including representatives of all the major animal groups, focusing in particular on those that diverged very early.

The analysis confirms the conclusion reached in an earlier study, which dated the origin of animals to the Neoproterozoic Era, which lasted from 1000 to 540 million years ago. However, much to their surprise, the results also suggested that the earliest phyla, and the ancestors of all bilateral animal species (the so-called Bilateria), originated within the -- geologically speaking -- short time-span of 50 million years. "In addition, this early phase of evolutionary divergence appears to have preceded the extreme climate changes that led to Snowball Earth, a period marked by severe long-term global glaciation that lasted from about 720 to 635 million years ago," Dohrmann says. In order to assess the plausibility of the new findings, the researchers plan to carry out further analyses using more extensive datasets and improved statistical methods." To arrive at well-founded conclusions with respect to the morphology and ecology of the earliest animals, we also need to know more about the environmental conditions that prevailed during the Neoproterozoic, and we need more fossils that can be confidently assigned to specific taxonomic groups," Wörheide says.

From Science Daily

A new web of life: First full family tree of the world's spiders

Leucauge venusta suspended from its web.

For the first time biologists have made a full family tree of the world's spiders, giving us knowledge about venoms that can be useful in medicine. And we might be able to develop silk just as good as the spider's.

They may make you cringe in horror, or they may intrigue you. Some even have them as pets.

Regardless of how you judge them, spiders are a plentiful and widespread group of animals. They have been around for 400 million years, count 45,000 species, and crawl around on nearly every terrestrial habitat in in the world.

For long, researchers have tried to unlock the secrets to their evolutionary history, striking diversity and success.

First of its kind

One team, including Dimitar Dimitrov from the Natural History Museum in Oslo, has taken this task to an unrivalled level, sampling 932 spider species from across the globe, representing every but one of the world's 116 known families.

The spiders of the last family are extremely small, and involving them was too complicated. But they are not really significant in this context, Dimitrov says. They will be included in further analyses.

The spiders were sequenced for several gene markers and then compared to each other, analyses in which Dimitrov was heavily involved. Simply put, the more similar the genetic code is between two species, the more closely they are related.

The team was thereby able to order and place the different spider branches in relation to each other, reconstructing their history through a so-called phylogenetic tree (see fact box).

"It is the most comprehensive study of spiders' evolution until now," says Dimitrov.

Drivers of diversification

One of the main challenges for understanding spider evolution is the identification of the drivers that have led to spider diversity.

"Our findings are important for understanding how different characters such as webs, vision or venoms have evolved and have affected the diversification of different groups that have these characters. For example why do some families have thousands of species and others just a few? Now that we have a large-scale phylogeny we may actually address this question combining information on traits and natural history with the tree," the entomologist explains.

Far reaching applications

The newly spun web of life not only alters our understanding of spiders, but may also impact disciplines such as material science and medicine, the researchers claim. "Spiders' venoms are exceptionally diverse in terms of their components. Thus, having a large tree of spiders will help us understand how those have evolved. We can also use the tree to predict the venom type of spiders that have not been studied. This is also important for medical applications as some of the venom components are used in the pharmaceutical industry."

Another alluring prospect relates to the manufacture of artificial silk, which material scientists try to copy with the same extreme strength and elasticity as silk produced by spiders.

"As of now there is no artificial fiber that can match the spider silk properties. In the future," Dimitrov explains, "the research team may supply the current tree with even more species and genomic data, which may further resolve uncertain parts of the tree."

Big picture science

"What I like most about this type of studies is that they provide you with the "big picture," a perspective that is hard to gain otherwise. Yet it is necessary to put more specific studies into a general evolutionary context," Dimitrov explains.

"For example, it is really hard to gain a deep understanding on the evolution of traits if one is looking at a specific trait in just a few species."

Envision two separate species. Both of them only thrive in a harsh and arid environment and happen to look alike. Did they adapt to the arid habitat independently or did they inherit this ability through a common ancestor?

"The two options would imply rather radical differences in our understanding of adaptations to arid environments. If it happened independently, one would suggest that this might be common, while the other would suggest it is as a rate event. If we lack a phylogenetic perspective we cannot really tell which one would be the case."

Read more at Science Daily

Squid - 'Weeds of the Sea' - on the Rise

Squid, octopus and cuttlefish are on the rise, finds new research on these animals, which are collectively known as cephalopods.

Nicknamed the “weeds of the sea,” these animals have experienced impressive population growth over the past 60 years and at a time when many fish species have been declining in numbers, according to the new study, which is published in the journal Current Biology.

“Our analyses showed that cephalopod abundance has increased since the 1950s, a result that was remarkably consistent across three distinct groups,” lead author Zoë Doubleday, a researcher at the University of Adelaide’s Environment Institute and School of Biological Sciences, said in a press release.

“Cephalopods are often called ‘weeds of the sea’ as they have a unique set of biological traits, including rapid growth, short lifespans and flexible development,” Doubleday continued. “These allow them to adapt to changing environmental conditions (such as temperature) more quickly than many other marine species, which suggests that they may be benefiting from a changing ocean environment.”

What sparked the research was an observed decline of a species that’s iconic down under: the giant Australian cuttlefish.

Doubleday explained that researchers started to notice fewer of these cuttlefish at the cephalopod’s world-renowned breeding ground in South Australia’s Spencer Gulf.

The scientists compiled a global-scale database of cuttlefish, as well as squid and octopus. Not only did the study reveal that the giant Australian cuttlefish is already making a major comeback, but also that most other related animals have been increasing in numbers over the past six decades.

Like weeds taking over a garden, however, the news isn’t all good.

Co-author Bronwyn Gillanders said large-scale changes to the marine environment, brought about by human activities, could be driving the global increase in cephalopods.

Read more at Discovery News

Leprosy Threatens Red Squirrels in UK

A squirrel native to Britain that was already in trouble now needs help with another threat: leprosy.

The disease results in swelling in the animal’s snout, feet and ears, as well as hair loss, and wildlife officials in the United Kingdom are launching a study to figure out how it is being transmitted, according to the Daily Mail.

The major problem for the ruddy creatures is that their historic turf has been overrun by grey squirrels introduced from the United States. There are just an estimated 140,000 red squirrels left in the U.K., compared to some 2.5 million grey squirrels, according to England’s forestry commission.

Leprosy was first discovered in the U.K.’s red squirrels in Scotland in 2014, although experts think it has been around for a long time – perhaps hundreds of years — and simply gone undiagnosed.

According to Dorset Wildlife Trust, which will participate in the study, the leprosy bacteria is "widespread" among the squirrels but "neglible" in terms of risk to humans. Scientists with the organization aren't sure yet how the disease is being transmitted among the squirrels.

Ground zero for the leprosy study will be Brownsea Island, a site thought to be a hotbed for the disease and one that will enable the scientists to study it in a contained setting.

Researches from the University of Edinburgh, alongside local wildlife managers from Brownsea Island, will conduct the study using humane traps. They'll capture the animals long enough for blood tests and basic health exams to be administered, before returning them to the wild.

From Discovery News

Insect Panama Papers? Corruption Exists Among Animals, Too

Humans are a cooperative species by nature, but no doubt there are many individuals who prioritize their own interests to the detriment of the greater good. Look no further than the recent news around the “Panama Papers,” a 2.6-terabyte data leak from the law firm Mossack Fonseca documenting how companies, political leaders, wealthy individuals and even criminals hide their assets.

Corruption isn’t exclusively a human vice, though; animals do it, too. Even eusocial species — highly organized, cooperative animals that share in the responsibility of raising offspring and have a clear division of labor — will cheat each other when given the opportunity.

Take ants, for example. A model of cooperation in the animal kingdom, ants cluster into highly organized colonies, with labor divided among workers, soldiers, drones and a queen. A 2008 study on leaf-cutter ants published in the Proceedings of the National Academy of Sciences, however, found the ant world rampant with cheating and corruption.

How exactly does an ant cheat the system to get ahead? While researchers had believed that all larvae had the opportunity to develop into queens so long as they were fed certain foods, DNA fingerprinting found that the offspring of some ant fathers were more likely to become queens than others, according to biologist Bill Hughes, then of the University of Leeds. These ants possess a “royal” gene that gives them an advantage over other ants, cheating the others out of a chance to become queens.

These royal genes are exceedingly rare within an ant colony, “an evolutionary strategy by the cheaters to escape suppression by the altruistic masses they exploit,” Hughes said.

Bees aren’t much better. Like ants, bees exist in stratified societies, separated across workers, drones and a queen. Offspring within a colony are produced entirely by the queen, a kinship meant to hold together bees’ social structure — or at least that’s how it’s supposed to work.

According to a 2009 study published in Molecular Ecology, worker bees within the species Melipona scutellaris, a stingless Brazilian bee, will reproduce behind the queen’s back. The study, which examined the lineage of 600 males across 45 colonies, found that nearly a quarter of the bees were sons of workers rather than the queen. Rather than cooperating, the workers were instead in conflict with their queen.

Reproduction isn’t really about passing genes on to the next generation in this case. Instead, worker bees that are reproducing live almost three times longer than those that don’t, nearly matching the life expectancy of the queen. The reason why is that reproducing worker bees usually do a lot less work and avoid potentially dangerous tasks like foraging. The individual benefits for reproductive worker bees come at a cost for the entire colony, of course. The more worker bees there are reproducing, the lower the collective production of the colony and the worse off everyone is.

This reproductive tug-of-war between workers and queens isn’t unique to Melipona scutellaris. A 2013 study on honeybees (Apis mellifera) found evidence of a similar conflict.

Read more at Discovery News

Frozen Animal Brought Back to Life After 30 Years

An animal that had been frozen for 30 years has been revived by scientists — and it then successfully reproduced.

The animal in question was a species of tardigrade, a microscopic creature sometimes referred to as a “water bear” that is perhaps the hardiest lifeform on Earth. There are over1,000 known species, all of which have eight legs and measure between 0.5 and 1.2 mm in length, and they are found more or less everywhere.

As Brian Resnick wrote recently for Vox: “Pick up a piece of moss, and you’ll find tardigrades. In the soil: tardigrades. The ocean: You get it. They live on every continent, in every climate, and in every latitude. Their extreme resilience has allowed them to conquer the entire planet.”

This resilience comes from tardigrades’ ability, when conditions are especially harsh, to enter a state known cryptobiosis (or anabiosis). They achieve this by expelling 95 percent or more of their water, creating proteins and sugars to protect their cells, massively reducing or even suspending their metabolism, and tucking in their heads and legs to form a pill-shaped “tun.”

In tun form, tardigrades can withstand conditions from boiling water to absolute zero, and pressures six times greater than those found in the deepest part of the ocean. In 2007, the European Space Agency even launched a payload of tardigrades in tun form into space; retrieved 10 days later after the satellite returned to Earth, some of the tardigrades came back to life upon rehydration and even went on to reproduce, the first animals to survive the vacuum of space.

Even by tardigrade standards, however, the most recent example of survival skills is impressive. The water bears in question were in a moss sample that was collected in November 1983 during a Japanese research expedition to Antarctica. The moss was stored at -20 degrees C after collection. In May 2014, researchers began to thaw out the moss, teased it apart with tweezers and found two tardigrades — which they delightfully dubbed Sleeping Beauty 1 and 2 (or SB-1 and SB-2 to their friends) — in tun form.

Recovery was steady but slow, the researchers write in the journal Cryobiology: “SB-1 first showed slight movement in its 4th pair of legs on the first day after rehydration. This progressed to twisting of the body from day 5 along with movement in its 1st and 2nd pairs of legs, but the movements remained slow. After starting to attempt to lift itself on day 6, SB-1 started to slowly crawl on the agar surface of the culture well on day 9, and started to eat the algal food provided the culture plate on day 13.”

Read more at Discovery News

Snake-Killing Fungus in Eastern U.S. Identified

Snake fungal disease (SFD), a frequently deadly skin infection found in snakes in the eastern half of the United States, now has a known cause: a fungus called Ophidiomyces ophiodiicola.

That's according to new research published in the online journal mBio by scientists from the U.S. Geological Survey (USGS).

Since 2009, SFD has been documented by the USGS in seven snake species across nine eastern U.S. states. The infection in some species, such as the massasauga rattlesnake in Illinois, is almost always fatal, researchers say, while in other species the impact is not always so dramatic.

Scabs, scales, and opaque eye cloudiness not related to skin molting are among the typical clinical signs of SFD, according to the USGS.

By inoculating laboratory snakes with cultured O. ophiodiicola, a research team led by USGS National Wildlife Health Center microbiologist Jeffrey Lorch was able to prove definitively that the fungus was behind SFD.

SFD is reminiscent of other fungal diseases currently ravaging animals such as bats, with white-nose syndrome, and frogs, with chytridiomycosis. For some snakes, then, the stakes could not be higher.

"There is a fear that Ophidiomyces could drive at least some populations of snakes to extinction," said Lorch, in a statement.

It's still not certain exactly how the disease causes death in the wild, though Lorch thinks a number of factors combine to kill the animal.

"It could be due to predation or exposure if snakes are out and about when they shouldn't be," he said. "They could be getting secondary skin infections if bacteria get in."

Meanwhile, the mortality rate of FSD has been tough to peg, thanks to a lack of long-term data on the condition as well as the difficulty in studying the solitary, often inscrutable nature of snakes.

Read more at Discovery News

Sea Otter with Asthma Learns to Use an Inhaler

The air was hazy from forest fires, and Mishka, a 1-year-old sea otter at the Seattle Aquarium, could barely breathe.

Aquarium staff jumped into action, putting an oxygen mask on the 45-lb. (20 kilograms) sea otter and administering anti-inflammatory medication to help her breathe. After several medical tests, Mishka became the first-known sea otter (Enhydra lutris) to be diagnosed with asthma.

Now, trainers are teaching Mishka how to use an inhaler — one that's not designed for sea otters (after all, Mishka is the first one) but for cats, said Seattle Aquarium staff veterinarian Dr. Lesanna Lahner.

"She's very smart, and she's picking it up quite quickly," Lahner told Live Science. "But being an otter, she's also extremely playful. So we have to work with her and with her playfulness to make it fun."

Mishka is relatively new to the Seattle Aquarium. The Alaska native was rescued after people found her tangled in a fishing net in July 2014, according to the aquarium. She spent the next several months in rehabilitation at the Alaska SeaLife Center. However, the U.S. Fish and Wildlife Service deemed her nonreleasable because she never learned critical survival skills, such as how to forage for food, and thus would be unable to survive in the wild, Lahner said.

Zookeepers named her Mishka, Russian for "little bear," when she arrived in Seattle in January. They didn't realize she had asthma until months later, when smoke from the forest fires in eastern Washington floated over the Cascade Range mountains into western Washington.

On Aug. 22, zookeepers noted that Mishka was acting lethargic and not eating much.

"It's abnormal for a sea otter not to eat pretty voraciously," Lahner said.

The next day, Mishka had a full-blown asthma attack, prompting immediate treatment.

Afterward, Lahner took a blood sample to make sure Mishka didn't have pneumonia or another respiratory pathogen (she didn't). Then, Lahner listened to Mishka's lungs with a stethoscope and took a radiograph of the animal's chest. The results pointed toward asthma, she said.

The radiograph showed that Mishka had abnormal thickening on her bronchial walls. This can make it difficult for enough oxygen to enter the lungs — a pattern that "is typical of what is seen in cats presenting with acute asthma," Lahner said.

Trainers are giving Mishka food rewards to use a device called the AeroKat, which has a chamber filled with aerosolized medicine. Mishka is learning to put her nose against a rubber face piece that's connected to the medicine-filled chamber, and take a couple of breaths.

Read more at Discovery News

New Millipede Species Is an 'Avatar'

This blue 'avatar' is a new species of millipede.

Scientists have used high resolution technology for the first time to describe a new millipede species, highlighting features such as genitals in remarkable detail.

The millipede, dubbed Ommatoiulus avatar, was found in an Andalusion pine forest in southern Spain.

Researchers first used iodine to stain different organs in the species and then scanned it using microCT (high-resolution x-ray microtomography)

Data produced by the scans, collectively called a 'cybertype', was then rendered as a 3D image using transparency and colour to reveal different parts of the creature.

The male genitals (gonopods), which are key in the identification of millipedes are seen in orange at the base of the image.

The eyes are seen in yellow at the top of the image and are not, as you might think, where the antennae attach.

Taxonomy can often be a painstaking business. If someone wants to study the original type specimen -- or holotype -- used to identify a species, they may have to travel far to find it, or request a museum send the specimen to them.

And any study, especially dissection, may damage the precious and often fragile original specimen.

But, says biologist Dr Brian Metscher of the University of Vienna, who helped create the new images, microCT scans can help get around this problem.

"If we make images like this, one does not have to dissect the specimen and it can remain intact, happy and safe in the museum."

Instead of actual dissection, researchers can rotate the digital images, change the focus of them, or delete unwanted sections, to get a clear picture of what they need to, says Metscher.

Metscher and colleagues have documented procedures on how to make cybertypes and also share them around the world.

While the holotype specimens are kept in museums in Vienna and Copenhagen, all 3D images and data have been placed on the open access online repository called Dryad.

"We hope that this work will be an example for how to make, use, and share virtual specimens for taxonomy and other purposes, including teaching," says Metscher.

Read more at Discovery News

Elephant Skin Graft Gives Mutilated Rhino Second Chance

A rhinoceros in South Africa that was mutilated by poachers for its horn is getting a chance to recover after receiving a skin graft from an elephant, a veterinarian told AFP Saturday.

The female rhino was attacked two weeks ago by poachers who removed one of its horns and also killed the rhino's baby.

The operation to treat the wound took an hour and a half and was funded by the NGO "Saving the Survivors" which rescues animals left mutilated by poachers.

"This is the first time we are using elephant skin to heal a wound on a rhinoceros," said Johan Marais, the veterinarian who performed the operation in Pretoria.

Marais said that the procedure was not intended to reconstruct the horn, but simply to cover the wound.

The elephant skin came from an animal that died of natural causes, and was obtained from a taxidermist, Marais said.

The rhinoceros was treated last week, and it will take two to three weeks to know if the skin graft was successful, according to the veterinarian.

If all goes well, the technique could be used more often because only a small piece of skin is needed for the treatment.

Demand for rhino horns, which are used in traditional Asian medicine, has exploded in recent years. In China and Southeast Asia, a kilo of rhino horn sells for more than 55,000 euros (US $61,000).

From Discovery News

Supersniffing Ants Smell Things Humans Can't

Ants may be experts at sniffing out body odor, according to a new study that reveals these insects have a "high-definition ability" to detect tiny chemical changes in the pheromones other ants give off.

Scientists from the University of California, Riverside, studied how ants tell each other apart in their colonies based on tiny, nearly undetectable changes in how other ants smell. The research, published today (Aug. 13) in the journal Cell Reports, revealed how much ants' sniffing abilities may have been underestimated.

Social insects, like ants, detect each other's smells using sensors in their antennae. It was initially thought that ants used these smells to distinguish between friends and foes, but the new study suggests the insects' abilities go further than this.

The researchers tested how the ants react to different odors by sticking tiny glass electrodes into single sensory hairs on the insects' antennae, which were then exposed to puffs of different hydrocarbons. The electrodes acted like sensors to show whether each antenna was responding and if the ant had recognized a smell. The researchers discovered that ants are highly sensitive to chemical changes, with sensory neurons able to respond to a variety of subtly different hydrocarbon odors.

The scientists were also curious about whether the ants understood the actual chemical compound. So in a second experiment, the researchers paired one hydrocarbon with a sugary reward and one with plain water.

"We found that the ants were really superb at being able to make way to the hydrocarbon that had originally been paired with the reward," said study lead author Anandasankar Ray, an associate professor of entomology at the University of California, Riverside. "It's a very unusual ability that I think is unique to social insects that live in large colonies."

As it turns out, ants are quite the connoisseurs when differentiating among body odors. The Camponotus floridanus ants in this study have more smell-sensing genes than humans do, the researchers said.

Ray said that although people may be able to train themselves to distinguish among subtle variations in odors, such as the "difference between, say, a pinot noir and a cabernet," human noses are not up to the standards of ant antennae. In fact, most animals would not be able to detect the hydrocarbons in the study as a smell at all, he added.

"I think what is unique to the ants is that they are able to discriminate these very low-volatility chemicals — these hydrocarbons, which humans cannot perceive," Ray told Live Science.

How volatile a compound is refers to how easily it boils and turns into a gas to be smelled. Shorter hydrocarbon chains have fewer bonds that need to break, so they turn into gas faster. The hydrocarbons on the ants have low volatility, meaning they have long chains and low levels of the chemical evaporate at room temperature to be sniffed.

Detecting such small doses requires a meticulous sense of smell, which may have evolved as a way for ants to navigate their complex social networks, the researchers said.

"Imagine that there are hundreds and thousands of these social insects in a colony," Ray said. "It's really critical for them to be able to tell the difference between major worker, a minor worker, a queen and different individuals within a colony, in order to be able to coordinate their social experience."

The researchers said they think low-volatility hydrocarbons fit the bill for detecting such differences, because ants interact with each other in close quarters. If the odors were strong, the ants would likely get confused, the researchers said. Ants get so close when they touch antennae and sniff each other, it is the equivalent of "shaking hands and exchanging business cards," Ray said.

"If they were using volatile odors to try to recognize their peers, it would be a real mess because these volatile odors would be all over the colony," Ray said. "It would overrun them."

Read more at Discovery News

Queen Bees Vaccinate All of Their Babies

Bee babies enter the world naturally vaccinated, according to a new study that found queen bees inoculate all of their young.

The scientists learned how queen bees manage this feat, and plan to replicate it in future with the hope of boosting bee immunity even more. The findings appear today in the journal PLOS Pathogens.

“The process by which bees transfer immunity to their babies was a big mystery until now,” co-author Gro Amdam of Arizona State University said in a press release. “What we found is that it’s as simple as eating. Our amazing discovery was made possible because of 15 years of basic research on vitellogenin. This exemplifies how long-term investments in basic research pay off.”

Co-author Dalial Freitak of the University of Helsinki added, “I have been working on bee immune priming since the start of my doctoral studies. Now almost 10 years later, I feel like I’ve solved an important part of the puzzle. It’s a wonderful and very rewarding feeling!”

The researchers explained that, in a honeybee colony, the queen rarely leaves the nest, so worker bees must bring food to her. Forager bees gather pollen and nectar, but in doing so, gather pathogens in the environment too. The whole mix, bacteria and all, is used back at the hive to create royal jelly, which the queen ingests.

Once consumed, the bacteria are digested in her gut and wind up stored in the queen’s “fat body,” which is an organ similar to a liver. Pieces of the bacteria are then bound to a protein called vitellogenin, and are carried via blood to the developing eggs. Because of this, bee babies enter the world vaccinated.

The simple brilliance of the process is that the bees are specifically safeguarded against diseases present in their own environment.

These days, however, bees face less predictable challenges from human activities, such as pesticide use and sudden widespread transfer of plants/crops and bee pests, as well as climate change factors and other threats. During the past six decades alone, managed honeybee colonies in the United States have declined from 6 million in 1947 to only 2.5 million today.

Armed with the new knowledge about vitellogenin, the scientists are working on the first ever edible and natural vaccine for beneficial insects like bees.

“We are patenting a way to produce a harmless vaccine, as well as how to cultivate the vaccines and introduce them to bee hives through a cocktail the bees would eat,” Freitak said. “They would then be able to stave off disease.”

Read more at Discovery News

Plants Release Animal-like Substance When Stressed

Although plants do not have nervous systems, they respond to stress with chemical and electrical signals that are remarkably similar to those of animals, a new study has found.

The findings, published in the journal Nature Communications, could help to explain why certain plant-derived drugs work so well in humans.

At the center of it all is the neurotransmitter GABA (gamma-aminobutyric acid), which humans and animals, as well as plants, release when they are stressed out.

“We’ve known for a long time that the animal neurotransmitter GABA is produced by plants under stress, for example, when they encounter drought, salinity, viruses, acidic soils or extreme temperatures, but it was not known whether GABA was a signal in plants,” senior author Matthew Gilliham of the University of Adelaide’s School of Agriculture, Food and Wine said in a press release.

He continued, “We’ve discovered that plants bind GABA in a similar way to animals, resulting in electrical signals that ultimately regulate plant growth when a plant is exposed to a stressful environment.”

Co-author Stephen Tyerman is optimistic that the discovery could lead to new ways of modifying how plants respond to stress. He explained that most yield losses from agricultural crops come from “major stresses” like pathogens and poor environmental conditions. If the plants succumb to these threats, food shortages may result.

Tyerman further explained that by “identifying how plants use GABA as a stress signal, we have a new tool to help in the global effort to breed more stress-resilient crops to fight food insecurity.”

The researchers suspect that GABA and its interaction with neurotransmitters evolved independently in the plant and animal kingdoms. This is because, while the proteins share many characteristics in common, some aspects of these same proteins are different between plants and animals.

Nevertheless, since the basic GABA signaling system exists within both groups, particular plant-derived drugs and other plant-based products often match well with our health needs. For example, chamomile is thought to bind to GABA receptors, acting as an inhibitory neurotransmitter. As a probable result, this natural ingredient tends to provide a gentle, natural feeling of calmness when consumed.

Read more at Discovery News

Deep-Diving Dolphins Avoid 'Bends' with Strong Lungs

When dolphins dive deep below the water's surface, they avoid succumbing to decompression sickness, or "the bends," likely because the massive sea creatures have collapsible lungs, a new study finds. These lungs allow dolphins to inhale and exhale two to three times quicker than humans.

Understanding how dolphins breathe rapidly and maintain lung functionality under immense pressure could help scientists keep humans safe when they are in similarly extreme situations, such as under anesthesia during surgeries, the researchers said.

Unlike humans, dolphins do not need to be strapped to an oxygen tank to achieve their impressive diving feats. This is because dolphins have compressible lungs that help them withstand high pressures deep in the ocean.

"The deeper go into the ocean, the smaller the volume of gas or air in the lungs gets," said study lead author Andreas Fahlman, a professor of biology at Texas A&M University in Corpus Christi. Fahlman found that dolphins can replace as much as 95 percent of the air in their lungs in a single breath. For comparison, humans are capable of replacing only as much as 65 percent. Dolphins exhale and then inhale above water before diving back down with lungs filled with air — each breath consumes and releases a certain amount of oxygen that energizes the animals as they swim the ocean.

The researchers studied six male bottlenose dolphins at Dolphin Quest Oahu, a dolphin training facility in Hawaii that is open to the public. The dolphins were free to swim away from the researchers whenever they wished, Fahlman said, though the animals were trained to sit still and breathe into a mask, called a pneumotachometer. This device essentially functioned as a "speedometer for the lungs," Fahlman said. The mask covered the dolphins' blowholes at the backs of their necks.

When trainers had dolphins breathe as hard as they could, in breaths researchers called "chuffs," the animals could inhale 8 gallons (30 liters) of air in one second, and exhale 34 gallons (130 liters) of air per second. A human's strongest exhale moves at a rate of 4 gallons (15 liters) per second, and human coughs range from about 10 to 16 gallons (40 to 60 liters) per second. In other words, dolphins move air two to three times faster than humans could ever do, Fahlman said.

Part of the reason dolphins are expert divers is because they can collapse their alveoli, the little sacks on the lungs that monitor air flow, and then open them up again, "but humans can't do that," Fahlman said.

This has implications for humans who are exposed to similarly extreme conditions, such as patients who undergo emergency operations.

"f you're in the hospital and you're undergoing surgery, oftentimes what they do is put a tube down your throat and put a positive pressure to prevent a collapse from happening," Fahlman said.

Putting positive pressure on the lungs keeps them open, but can also be dangerous, he added. "This is a clinically relevant issue for people in emergency care, for people undergoing surgery, because we cannot as easily open up the alveoli."

Fahlman said it's possible that dolphins' lungs look completely different from humans' or that dolphins have a very different biochemical composition in their lungs, which could explain their impressive exhalation abilities. Lungs typically contain a compound called surfactant, or pulmonary surfactant, that helps with breathing. Previous research found that surfactant in some seals and sea lions can keep the alveoli more lubricated so they open up easily.

All mammals use surfactant while breathing; it's a "way of trying to reduce the number of calories that it costs inhale and exhale," Fahlman said, adding that animals developed differences in surfactant to adapt to their environments.

Prematurely born babies benefit from surfactant manufactured from cows, Fahlman said, because the babies can't produce enough of the substance at such a young age.

Surfactant from dolphins and other sea mammals could be beneficial under different circumstances, he added. "We can learn about the structure of the surfactant [that animals] have and replicate it for humans," Fahlman said.

Studying animal breathing rhythms and capacities can also help scientists better understand respiratory disease in marine animals, which is a major cause of morbidity and mortality among marine animals in the wild and under human care, Fahlman said.

Humans are exposed to pollen, debris and other airborne pollutants that many dolphins and other mammals are unable to remove from their blowholes. This can make some animals susceptible to certain diseases like lung disease.

Fahlman said he plans to expand his research to beluga whales and porpoises to investigate their breathing patterns. He said there is especially high concern around mammals living in waters near oil rigs. Researchers are planning to travel to Alaska and the Arctic to study the mammals before oil reserves there are exploited, to establish a baseline for animal health, he added.

Read more at Discovery News

Are Bumblebees Getting Alzheimer's?

It’s no secret that bees are in crisis right now -- a recent 40 percent decline in bee populations has been blamed on harmful pesticides and mite infestations, but researchers have now identified yet another potential threat to the pollinators: aluminum.

According to a new joint study from Keele University and the University of Sussix, bumblebees are now suffering from troubling amounts of aluminum contamination, which could be the cause of debilitating cognitive dysfunction.

“Aluminum is a known neurotoxin affecting behavior in animal models of aluminum intoxication. Bees, of course, rely heavily on cognitive function in their everyday behavior and these data raise the intriguing specter that aluminum-induced cognitive dysfunction may play a role in their population decline: are we looking at bees with Alzheimer’s disease?” said Keele’s Chris Exley in a press release.

Exely and his colleague Dave Goulson tested the aluminum levels of pupae from bumblebee colonies. Whereas an aluminum level of 3ppm would be harmful to human brain tissue, some pupae were found to have aluminum levels as high as 200ppm.

The excess aluminum has a variety of origins, according to Exely and Goulson. “Human activities such as the burning of fossil fuels resulting in ‘acid rain,’ intensive agriculture producing acid sulphate soils and the mining of aluminum ores to make aluminum metal and salts have all contributed to the burgeoning biological availability of this non-essential metal,” they wrote.

Previous research has already linked high levels of aluminum exposure to the death of fish in acid lakes and low crop productivity in acidified soils.

From Discovery News

This Isn’t a Spider, But It Does Have Genitals in Its Legs

This isn't slowmo. It's how a sea spider actually moves. The critter was spotted 8,675 feet deep off the coast of Vancouver by a submersible manned by Ocean Networks Canada. Clearly, it won't even give submersibles the time of day.

So, good news and bad news for those of you afraid of spiders. Good news is, this creature isn’t a spider because spiders can’t breathe underwater, so you’re safe from arachnids if you want to spend more time in the ocean. (Well, one species of spider actually can live underwater by trapping air around its abdomen—sorry, I’m really bad at good news.) The bad news is what while the sea spider may not be an actual spider, it looks like the ghost of a spider you once killed. Which might actually be worse and … totally scientific?

The 1,300 known species of sea spider are truly ancient animals that as far as scientists can tell aren’t closely related to any extant species, spiders or otherwise. At the moment, though, they’re lumped in the group that holds spiders and horseshoe crabs. They have such tiny abdomens that their guts extend into their legs. Their genitals are there in the limbs too, which makes mating … interesting. And like sea horses, it’s the males that carry the young.

Sea spiders live in both deep and shallow seas around the world, but all are carnivores, through and through. They have claw-like mouthparts known as chelicerae, which spiders also have, suggesting they may belong to the same group (appropriately enough called Chelicerata). The actual feeding happens through a proboscis, a sort of tube that can be longer than the rest of the sea spider’s abdomen in some species.

“They feed generally on things that don’t move, like sponges and corals, but also slow-moving things like worms or sea slugs,” says marine biologist Claudia Arango of the Queensland Museum in Australia. “What they do is they’ve got very sharp jaws at the tip of that tube, the proboscis, so they pierce the prey and start sucking out fluids.”

The deep and shallows are of course worlds apart as far as habitats go, so sea spider species have adapted accordingly. To find food in the blackness, the blind deep-sea varieties likely sniff out their prey’s chemical cues, while their shallow-water peers have four simple eyes. In the shallows, they also tend to be more colorful than in the deep sea, since in the darkness, flashy colors won’t do you no good nohow.

The sea spider Nymphon grossipes, which really got short-changed on the whole name thing.

Their body plans, too, are wonderfully adapted for their environments. The long-legged species are built like the tripods from The War of the Worlds—but with fewer legs and death rays—because sediment down in the deep can be soft and unstable, so lankier limbs keep it from sinking up to its abdomen. In the shallows, sea spiders tend to be stouter, with thicker, shorter legs that help them better hold on in rough waters, not to mention avoid shattering into a shower of limbs.

Leg Genitals and Other Adventures in Sea Spider Sex

What the many species of sea spider can agree on, though, is how to have sex: namely, very acrobatically. Both males and females have genital pores in their legs, males on just their last two pairs and females on every single limb. When a couple comes together the spindly male crawls on top of the spindly female. “So basically he climbs up and walks all over the female and then starts trying to go under the female so that both the pores come in contact,” says Arango. “The female would be standing totally normal while the male would be upside down, clinging on the female.”

Pseudopallene harrisi, from Australia. Note the claw-like chelicerae. It’s fashionably colorful not because it’s from Australia, but because that’s par for the course for shallow-water sea spiders.

When the female releases her eggs, the male combines them with his sperm and bundles them together in balls. These he holds with special appendages, known as baby björns ovigers, and “he carries the eggs all the way until they hatch, and sometimes even later you can see fathers carrying the babies,” says Arango. “It’s quite a heavy load sometimes.”

Inevitably, though, the larvae must set out on their own, and some species won’t just float at the mercy of the currents. They’ll invade the bodies of other creatures on the seafloor, including bivalves, burrowing into their flesh and feeding on them and eventually killing them. Others invade the bodies of coral, stealing the nutrients that algae produce for them.

A sea spider male carries eggs with specialized limbs called ovigers.

Still other species go after creatures called hydroids. One particular sea spider (.pdf) parasitizes the hydroid Tubularia larynx, a sort of small tube with frilly pink polyps, which grows en masse on rocks. The male sea spider will carry his young to fields of these hydroids and release them. Amid plenty of food, the young invade the hydroids’ tissues, feeding and feeding and growing and growing before erupting out of their dead hosts.

File Sea Spiders Under: It’s Complicated

It should be clear by now that sea spiders aren’t like any other creature on Earth—not by a long shot. I mean, the body plan alone is out of control. The daddy long legs is a lanky little thing, but the sea spider has so simplified its body plan that really its abdomen is little more than a joint for its legs, forcing its organs to flow into its limbs. Its heart is exceedingly simple, and because it lacks gills, it seems to absorb oxygen through its cuticle. And it has that bizarre proboscis, plus the males have those unique specialized arms used to hold eggs.

It all adds up to large-scale befuddlement for the folks studying them, and accordingly it’s a matter of controversy where exactly sea spiders fall in the tree of life. But Arango has an idea. “When you look at the morphology of the sea spiders, apart from a superficial resemblance to spiders, there’s lots of things that are unique,” says Arango. “In terms of giving them a place in the classification the best thing we can do, based on DNA mostly, is keep them at the base of the chelicerates.”

Anoplodactylus evansi may be Australian, but it looks a lot like a St. Louis Blues fan.

The problem is that sea spiders are a very, very old group of animals that likely diverged early on in the evolution of arthropods. I’m talking more than 500 million years ago, not all that long after the appearance of the first creatures we’d even recognize as animals. But for all that time on Earth, their fossils are scant, so tracing their lineage is a nightmare. And it doesn’t help that anatomically, they’re like nothing else living on this planet.

Read more at Wired Science

When Will We See an Actual Dino-Chicken?

Talk of a “chickenosaurus” lit up the science world last week when researchers announced they had modified the beak of a chicken embryo to resemble the snout of its dinosaur ancestors. But although some experts have lauded the feat, a beak is just one of many modifications needed to revert a chicken into a dinosaur.

Given these obstacles, how close are scientists to creating a dino-chicken?

“From a quantitative point of view, we’re 50 percent there,” said Jack Horner, a professor of paleontology at Montana State University and a curator of paleontology at the Museum of the Rockies.

Horner has long supported the idea of modifying a chicken to look like a dinosaur, and unlike the researchers on the latest study, he actually wants to raise a live one. And why stop there? By understanding how and when to modify certain molecular mechanisms, countless changes could be within reach. As Horner pointed out, a glow-in-the-dark unicorn is not out of the question.

There are four major modifications needed to make a so-called chickenosaurus, Horner said. To turn a chicken into a dinosaurlike beast, scientists would have to give it teeth and a long tail, and revert its wings back into arms and hands.

The creature would also need a modified mouth — a feat accomplished by the researchers who did this latest study, he said.

“This dino-chicken project — we can liken it to the moon project,” Horner told Live Science. “We know we can do it; it’s just there are … some huge hurdles.”

Challenges ahead

One of those “huge hurdles” was cleared in the latest study, published May 12 in the journal Evolution, in which researchers turned chicken beaks into dino snouts. But even that seemingly small step involved seven years of work. First, the researchers studied beak development in the embryos of chickens and emus, and snout development in the embryos of turtles, alligators and lizards.

It’s likely that millions of years ago, birds and reptiles had similar developmental pathways that gave them snouts, but over time, molecular changes led to the development of beaks in birds, the researchers said.

It’s difficult for scientists to get embryos of present-day animals, such as crocodiles, to compare because they have to find farms that raise them. And then, the molecular work — determining exactly which developmental pathways are different, how they’re different and what controls them — can take “countless hours and hundreds of experiments for a few successful ones,” said the study’s lead researcher, Bhart-Anjan Bhullar, a paleontologist and developmental biologist currently at the University of Chicago and cross-appointed at Yale University, where he will be starting as full-time faculty. “It’s kind of the same as fossil finding.”

For their “fossil finding,” the researchers needed an extensive fossil record of birds and their ancestors to see what birds looked like at different stages of their evolution.

“You have to understand what you’re tracing before you try to trace it,” Bhullar told Live Science.

Bhullar; his doctoral advisor Arkhat Abzhanov, a developmental biologist at Harvard University; and their teammates focused on two genes that are active in facial development. Each gene codes a protein, but the proteins — which carry out the work of genes — showed different activities in modern-day chicken and reptile embryonic development, the researchers found. When the researchers blocked the activity of these two proteins in chickens, the birds developed structures that resembled snouts, not beaks.

Unexpected find

And then there’s the unexpected finding that revealed the complex task at hand: When the group transformed the beaks of chicken embryos into snouts, they also inadvertently changed the chicken’s palate, or roof of the mouth.

In contrast, the palates of the bird embryos were broad and flat, and connected “to the rest of the skull in a way that ancestral reptiles’ palatines did, but bird palatines do not,” Bhullar said.

In birds, “the palatine bone is really long and thin, and it’s not very connected with other bones of the skull,” Bhullar said.

In fact, birds can lift up their top jaw independently of their lower jaw — an ability not seen in most other vertebrates.

So, by changing the beak, the researchers also changed the palate. When the researchers went back to the fossil record, they found that the snout and palatine bone appeared to change together throughout evolution. For instance, an 85-million-year-old fossil of a birdlike creature that had teeth and a primitive beak also had a birdlike palate, they said.

However, in an even older fossil, the palatine was not transformed, and neither was the beak, Bhullar said.

“Part of that is verifying experimentally whether the molecular changes we see are actually able to change the anatomy in the ways we predicted,” Bhullar said. “In a way, that recapitulates the change we see in the fossil record.”

But his goal “is simply to understand, in as a deep a way as possible, the molecular mechanisms behind major evolutionary transitions,” he said. He’s not interested in making “a more nonavian, dinosaurlike bird.”

Will it work?

But Horner is interested in making a so-called chickenosaurus. His group is currently working on giving the chicken a long tail— arguably, the most complex part of making a dino-chicken, he said. For instance, they just screened genes in mice to determine what types of genetic pathways block tail development. This knowledge could help them figure out how to switch on tail growth, he said.

But it remains to be seen how chickens would react to tails, arms, fingers and teeth, Bhullar said.

But, on the other hand, chickens may be resilient creatures."Just because you changed one part doesn't mean that the animal will be able to use it or be able to use it correctly," he said. "You could perhaps give a chicken fingers, but if the fingers don't have the right muscles on them, or if the nervous system and the brain are not properly wired to deal with a hand that has separate digits, then you may have to do a considerable amount of additional engineering."

"People also sometimes underestimate plasticity of the body," Bhullar said. "It's amazing how much compensation goes on, and the nervous system, in particular, is very plastic."

Bhullar said that, if dinosaur-like features, such as a snout and teeth, were to be restored, he wonders "whether the brain wouldn't rewire itself in some way that would permit these animals to use these features."

Read more at Discovery News

Common Bacterium Cures Bats' White-nose Syndrome

A common bacterium we find in everyday things, like food flavorings, is giving scientists hope that bat populations can be saved from deadly White-nose Syndrome.

The new treatment was developed in Missouri by Forest Service scientists Sybill Amelon and Dan Lindner, and Chris Cornelison of Georgia State University.

The bacterium, Rhodococcus rhodochrous, dwells in pretty much all soils found in North America and is safe for plants and animals. In fact, it’s been used in more than one industrial application, including flavorings for our food, for over half a century, according to the U.S. Forest Service.

This time, the researchers grew the bacterium on cobalt, which produced so-called volatile organic compounds (VOCs) that stop the fungus, Psuedogymnoascus destructans, from growing.

“The amazing part about this is that these compounds diffuse through the air and act at very low concentrations, so the bats are treated by exposing them to air containing the VOCs (the compounds do not need to be ‘directly’ applied to the bats),” according to a USFS press release.

However, more than one chemical is created from the reaction, so the scientists’ next step is to isolate which chemical is the one that stops the fungus from growing.

White-nose Syndrome attacks a bat’s nose, ears, and wings while it hibernates, when the animal’s temperature is at its lowest. All infected bats in a colony die, usually because their immune systems are compromised and they use twice as much energy during hibernation as healthy bats do, shedding precious fat reserves too early, according to researchers.

The disease has been plowing through bat populations since the early 2000s, killing nearly 6 million bats since 2006, according to WhiteNoseSyndrome.org. Twenty-six U.S. states have confirmed the presence of the disease.

If there’s no cure found for White-nose Syndrome, many scientists fear that bats will be extinct within a few decades.

Read more at Discovery News

Tarantulas Get Clumsy When It's Hot

The tarantula is a fast-moving spider, but it's not always a coordinated one, a new study finds. As the arachnid increases its speed, it also loses some of its coordination, becoming a "little wonky," researchers said.

Spiders have developed a unique way to move around: Rather than relying mainly on muscles to move, they use a fluid called hemolymph, which is their blood. When hemolymph flows into their tubelike legs, the limbs extend and their flexor muscles bend the legs at the joint, causing that fluid to flow back out.

Temperature can change the thickness, or viscosity, of hemolymph, said the study's senior author, Anna Ahn, an associate professor of biology at Harvey Mudd College in California.

"I always tell people, 'I can convince you that spiders are cool,'" Ahn said.

The researchers studied eight adult Texas brown tarantulas (Aphonopelma hentzi). They tested the spiders' speed and agility at four different temperatures: 59, 75, 88 and 104 degrees Fahrenheit (15, 24, 31 and 40 degrees Celsius). When the spiders were placed in temperatures that were higher or lower than that range, they tended to turn around and get into an attack stance, Ahn said.

Spiders have two joints along each leg, and the one closest to the body typically extends first when they're walking or running. To calculate each spider's coordination, the team painted a white dot on each of the joints on a foreleg and hind leg, and compared the angle of the two joints on each leg. Then they filmed the spiders scuttling down a runway.

"They're actually a little skittish and shy," she said. "All you had to do was blow a puff of air on them and they would run away from you."

At lower temperatures, the spiders moved more slowly, likely because the hemolymph was more viscous than at higher temperatures, Ahn said. Still, lower temperatures had a perk: The tarantulas had more coordination when the thermometer read 59 or 75 F.

"But at the higher temperatures, and the faster running speed, the two joints were less coupled," or less coordinated, Ahn said. "The two joints on each leg were a lot less well controlled at the higher temperatures."

To give an idea of the spiders' speed, imagine a 2.1-inch (5.5 centimeters) tarantula. On average, the spiders moved about four body lengths a second at 62 F (17 C), and about 10 body lengths a second at 100 F (38 C), a 2.5-fold increase.

But it would be difficult to catch the tarantula's unsteadiness with the naked eye. They move fast, and the researchers had to slow down the video in order to calculate the angle of each leg. Regardless, the spiders' instability at high temperatures may explain why some tarantulas emerge at dusk, when the weather is cooler, Ahn said.

Read more at Discovery News