Cougars and foxes in Chile, new research


This 2017 video from Ecuador is called Andean Fox (Culpeo)!

From Virginia Tech university in the USA:

What does the fox say to a puma?

Predators form an unusual coexistence in the central Chilean Andes

November 13, 2020

Summary: Researchers have found that in the Chilean Andes, two predator species — the puma and the culpeo fox — can successfully share a landscape and hunt for food over the same nighttime hours because they are, in essence, ordering from different menus.

In the high plains of the central Chilean Andes, an ecosystem consisting of only a few animal species is providing researchers with new insights into how predators coexist in the wild.

“The puma and the culpeo fox are the only top predators on the landscape in the Chilean Andes,” said Professor Marcella Kelly, of the College of Natural Resources and Environment. “And there isn’t a wide range of prey species, in part because the guanacos [closely related to llamas] aren’t typically found in these areas anymore due to over-hunting. With such a simplified ecosystem, we thought we could really nail down how two rival predators interact.”

Kelly worked with Christian Osorio, a doctoral student in the Department of Fish and Wildlife Conservation, and researchers from the Pontifical Catholic University of Chile to chart the locations of and potential interactions between pumas and foxes in central Chile. They focused on three axes of interaction: spatial (where the animals are on the landscape), temporal (the timing of specific activities on a given landscape), and dietary (what each species is eating).

To understand the interplay between pumas and foxes, researchers deployed 50 camera stations across two sites in central Chile, one in the Rio Los Cipreses National Reserve and another on private land where cattle and horses are raised. They also collected scat samples at both locations to analyze the diets of pumas and foxes.

The team’s findings, published in the journal Diversity, showed that while pumas and foxes overlapped significantly where they lived and what time they were active, there was little overlap in what they were eating, with the puma diet consisting primarily of a large hare species introduced from Europe, while the culpeo foxes favored smaller rabbits, rodents, and seeds. The two predator species can successfully share a landscape and hunt for food over the same nighttime hours because they are, in essence, ordering from different menus.

“It is likely that foxes have realized that when they try to hunt hares, they might run into trouble with pumas,” Osorio explained. “If they are hunting smaller mammals, the pumas don’t care, but if the foxes start targeting larger prey, the pumas will react.”

How predator species interact is a crucial question for ecologists trying to understand the dynamics that inform ecosystem balances. And while the puma has been designated a species of least concern, the animal’s populations are declining and continue to be monitored by conservationists.

“Least concern does not mean no concern,” Osorio noted. “We have laws in Chile that protect the species, but the data we have to make a conservation designation are very scattered. As we accumulate more consistent and reliable data, the puma may be reclassified as vulnerable or even endangered.”

The hares that comprise approximately 70 percent of the biomass in the puma’s diet are a nonnative species, introduced to the area by European settlers. With guanacos absent from the landscape, the puma has had to adapt its diet to survive.

With some land managers and conservationists campaigning for the removal of the introduced hare species as a way to restore the area’s native ecosystem, Kelly and Osorio note that it is important to understand that pumas would be significantly impacted by a reduction in their primary food source.

A further concern, which the two are currently researching, is the interplay between wildlife and humans. The national reserve increasingly sees visitors eager to witness big cats and foxes in their natural environment, while the sheep and cattle industries are increasingly using remote terrain for livestock cultivation.

“Pumas do occasionally kill livestock, which is a challenge we’re looking into right now,” said Kelly, an affiliate of Virginia Tech’s Fralin Life Sciences Institute. “The government would like to preserve the puma, but there are competing challenges of what kind of threat they pose to livestock and what kind of threat cattle or sheep farming poses to them.”

Understanding how two predatory species can come to coexist has the potential to provide conservationists and ecologists with better ideas for how humans and wild animals can share a landscape.

Permian-Triassic mass extinction and volcanoes, new research


This 2017 video is called Fireball Earth: The Permian Extinction – History Documentary.

From Tohoku University in Japan:

Large volcanic eruption caused the largest mass extinction

November 10, 2020

Researchers in Japan, the US and China say they have found more concrete evidence of the volcanic cause of the largest mass extinction of life. Their research looked at two discrete eruption events: one that was previously unknown to researchers, and the other that resulted in large swaths of terrestrial and marine life going extinct.

There have been five mass extinctions since the divergent evolution of early animals 450 — 600 million years ago. The third was the largest one and is thought to have been triggered by the eruption of the Siberian Traps — a large region of volcanic rock known as a large igneous province. But the correlation between the eruption and mass extinction has not yet been clarified.

Sedimentary mercury enrichments, proxies for massive volcanic events, have been detected in dozens of sedimentary rocks from the end of the Permian. These rocks have been found deposited inland, in shallow seas and central oceans, but uncertainty remains as to their interpretation. Mercury can be sourced from either direct atmospheric deposition from volcanic emissions and riverine inputs from terrestrial organic matter oxidation when land/plant devastation — referred to as terrestrial ecological disturbance — occurs.

The largest mass extinction occurred at the end of the Permian — roughly 252 million years ago. This mass extinction was marked by the transition from the divergence of the Paleozoic reptiles and marine animals like brachiopods and trilobites to Mesozoic dinosaurs and marine animals such as mollusks. Approximately 90% of species disappeared at the end of the Permian.

Current professor emeritus at Tohoku University, Kunio Kaiho led a team that looked into possible triggers of the largest mass extinction. They took sedimentary rock samples from two places — southern China and Italy — and analyzed the organic molecules and mercury (Hg) in them. They found two discrete coronene-Hg enrichments coinciding with the first terrestrial ecological disturbance and the following mass extinction in both areas.

“We believe this to be the product of large volcanic eruptions because the coronene anomaly was formed by abnormally high temperature combustion,” says professor Kaiho. “High temperature magma or asteroid/comet impacts can make such a coronene enrichment.

From the volcanic aspect, this could have occurred because of the higher temperature combustion of living and fossil organic matter from lava flows and horizontally intruded magma (sill) into the sedimentary coal and oil. The different magnitude of the two coronene-mercury enrichments shows that the terrestrial ecosystem was disrupted by smaller global environmental changes than the marine ecosystem. The duration between the two volcanic events is tens of thousands of years.”

Huge volcanic eruptions can produce sulfuric acid aerosols in the stratosphere and carbon dioxide in the atmosphere, which causes global climate changes. This rapid climate change is believed to be behind the loss of land and marine creatures.

Coronene is a highly condensed six-ring polycyclic aromatic hydrocarbon, which requires significantly higher energy to form as compared to smaller PAHs. Therefore, high temperature volcanic combustion can cause the coronene enrichments. This means that high temperature combustion of hydrocarbons in the sedimentary rocks by lateral intrusion of magmas formed CO2 and CH4 causing high pressure and eruption to induce global warming and the mass extinction. The coronene-mercury concentration firstly evidenced that volcanic hydrocarbon combustion helped contribute to the extinction through global warming.

Kaiho’s team is now studying other mass extinctions in the hopes of further understanding the cause and processes behind them.

Four gentoo penguin species, not one?


This 2019 video says about itself:

Gentoo Penguins Build Love Nests! | Penguin Post Office | BBC Earth

Why have a rock on your finger when you can have them in a nice neat pile? These Gentoo penguins have the right idea.

From the University of Bath in England:

Gentoo penguins are four species, not one, say scientists

November 3, 2020

Gentoo penguins should be reclassified as four separate species, say scientists at the Milner Centre for Evolution at the University of Bath, after analysing the genetic and physical differences between populations around the southern hemisphere.

The researchers say that counting them as four separate species will aid in their conservation because it will make it easier to monitor any decline in numbers.

Gentoo penguins, with the Latin name Pygoscelis papua, live in a range of latitudes in the southern hemisphere and are currently split into two subspecies, P. p. ellsworthi and P. p. papua.

The researchers suggest these two subspecies should be raised to species level and two new species created, which they have named P. poncetii after the Australian seabird conservationist Sally Poncet, and P. taeniata in recognition of a former proposal for this name dating to the 1920s.

Their study, published in the journal Ecology and Evolution, looked at the genomes of populations living in the Falkland Islands and South Georgia in the southern Atlantic Ocean, the South Shetland Islands in the Antarctic and Kerguelen Islands in the Indian Ocean.

They used genome data to create an evolutionary tree to understand the relationship between the different populations. When they combined these data with measurements of museum specimens from each of the populations, they found clear morphological (physical) and genetic differences between the four populations.

Dr Jane Younger, Prize Fellow from the Milner Centre for Evolution at the University of Bath, led the study. She said: “For the first time, we’ve shown that these penguins are not only genetically distinct, but that they are also physically different too.

“Gentoos tend to stick close to their home colonies, and over hundreds of thousands of years have become geographically isolated from each other to the point where they don’t interbreed with each other, even though they could easily swim the distance that separates them.

“The four species we propose live in quite different latitudes — for example P. ellsworthi lives on the Antarctic continent whereas P. poncetii, P. taeniata and P. papua live further north where conditions are milder, and so it’s not that surprising that they have evolved to adapt to their different habitats.”

PhD student Josh Tyler said: “They look very similar to the untrained eye, but when we measured their skeletons we found statistical differences in the lengths of their bones and the sizes and shape of their beaks.

“It’s a similar story to giraffes, which were revealed in 2016 to be four genetically distinct species.”

The scientists say that regarding the four populations as separate species, gives conservationists a better chance of protecting their diversity because if there’s a decline in one of them it will change the threat status as defined by the IUCN Red List.

Dr Younger said: “Currently gentoo penguins are fairly stable in numbers, however, there is some evidence of the northern populations moving further south as the climate gets warmer, so we need to watch them closely.”

The proposed changes to the classification of gentoos will be reviewed by an international committee of scientists which will assess all the evidence in the scientific literature before the new taxonomy is accepted.

The study was funded by the American Ornithological Society, Linnean Society, American Museum of Natural History and the Evolution Education Trust. The research team was a collaboration led by the University of Bath (UK) with scientists from Loyola University Chicago, Cornell University and the University of Minnesota (USA).

Dinosaur age mammals’ social life, new research


An artistic reconstruction of a social group of Filikomys primaevus in a burrow while dinosaurs roam above. Image credit: Misaki Ouchida

From the University of Washington in the USA:

New study finds earliest evidence for mammal social behavior

November 2, 2020

A new study led by paleontologists at the University of Washington and its Burke Museum of Natural History & Culture indicates that the earliest evidence of mammal social behavior goes back to the Age of Dinosaurs.

The evidence, published Nov. 2 in the journal Nature Ecology & Evolution, lies in the fossil record of a new genus of multituberculate — a small, rodent-like mammal that lived during the Late Cretaceous of the dinosaur era — called Filikomys primaevus, which translates to “youthful, friendly mouse.” The fossils are the most complete mammal fossils ever found from the Mesozoic in North America. They indicate that F. primaevus engaged in multi-generational, group-nesting and burrowing behavior, and possibly lived in colonies. Study co-authors — including lead author Luke Weaver, a UW graduate student in biology, and senior author Gregory Wilson Mantilla, a UW professor of biology and curator of vertebrate paleontology at the Burke Museum — analyzed several fossils, all about 75.5 million years old, and extracted from a well-known dinosaur nesting site called Egg Mountain in western Montana.

Fossil skulls and skeletons of at least 22 individuals of F. primaevus were discovered at Egg Mountain, typically clustered together in groups of two to five, with at least 13 individuals found within a 30 square-meter area in the same rock layer. Based on how well preserved the fossils are, the type of rock they’re preserved in, and F. primaevus’ powerful shoulders and elbows — which are similar to today’s living burrowing animals — Weaver, Wilson Mantilla and co-authors hypothesize these animals lived in burrows and were nesting together. Furthermore, the animals found were a mixture of multiple mature adults and young adults, suggesting these were truly social groups as opposed to just parents raising their young.

“It was crazy finishing up this paper right as the stay-at-home orders were going into effect — here we all are trying our best to socially distance and isolate, and I’m writing about how mammals were socially interacting way back when dinosaurs were still roaming the Earth!” said Weaver. “It is really powerful, I think, to see just how deeply rooted social interactions are in mammals. Because humans are such social animals, we tend to think that sociality is somehow unique to us, or at least to our close evolutionary relatives, but now we can see that social behavior goes way further back in the mammalian family tree. Multituberculates are one of the most ancient mammal groups, and they’ve been extinct for 35 million years, yet in the Late Cretaceous they were apparently interacting in groups similar to what you would see in modern-day ground squirrels.”

Previously, scientists thought social behavior in mammals first emerged after the mass extinction that killed off the dinosaurs, and mostly in the Placentalia — the group of mammals humans belong to, which all carry the fetus in the mother’s uterus until a late stage of development. But these fossils show mammals were socializing during the Age of Dinosaurs, and in an entirely different and more ancient group of mammals — the multituberculates.

“These fossils are game-changers,” said Wilson Mantilla. “As paleontologists working to reconstruct the biology of mammals from this time period, we’re usually stuck staring at individual teeth and maybe a jaw that rolled down a river, but here we have multiple, near-complete skulls and skeletons preserved in the exact place where the animals lived. We can now credibly look at how mammals really interacted with dinosaurs and other animals that lived at this time.”

New gall wasp species discovery


Allorhogas gallifolia is a new species of wasp discovered in live oak trees. First collected in 2014 by students in the lab of Rice evolutionary biologist Scott Egan, A. gallifolia is one of four new wasp species described in the study. (Credit: Ernesto Samacá-Sáenz/UNAM)

From Rice University in the USA:

Discovery adds new species a lab’s ghoulish insect menagerie

October 26, 2020

A horrifying insect soap opera with vampires, mummies and infant-eating parasites is playing out on the stems and leaves of live oak trees every day, and evolutionary biologist Scott Egan found the latest character — a new wasp species that may be a parasite of a parasite — within walking distance of his Rice University lab.

Egan, an associate professor of biosciences at Rice, studies gall wasps, tiny insects that cast a biochemical spell on live oaks. When gall wasps lay their eggs on oak leaves or stems, they chemically program the tree to unwittingly produce a tumor-like growth, or gall, which first shelters the egg and then feeds the larval wasp that hatches from it.

Egan describes the wasps as “ecosystem engineers,” because their galls are attractive morsels that harbor a supporting cast of opportunistic ne’er-do-wells, thieves and killers. It’s a great setting to study how competition for resources drives evolution, and Egan and his students have spent more than a decade documenting the eerie, interspecies who’s-eating-who drama.

The latest species they discovered at Rice, Allorhogas gallifolia (al-UHROH’-guhs GAHL’-ihf-ohl-eeuh), is one of four new wasp species from the genus Allorhogas that Egan and collaborators Ernesto Samaca-Saenz and Alejandro Zaldivar-Riveron at the National Autonomous University of Mexico (UNAM) in Mexico City described in a study this month in Insect Systematics and Diversity.

“They lay their egg in another wasp’s gall,” Egan said of A. gallifolia, which his group first hatched in 2014. “They’re using the gall as a resource, and we’re still not certain how, but I think they’re attacking herbivorous caterpillars that are feeding on the gall tissue, and the wasp larva are eating those caterpillars after they hatch.”

He said more than 50 species of Allorhogas have been found in Central America and Mexico, but only two species were previously documented in the United States, one at the University of Maryland campus in 1912 and another some years later in Arizona.

The A. gallifolia found at Rice was collected as part of an effort to describe the community of natural enemies for one species of gall wasp, Belonocnema treatae (behl-uh-NAHK’-nee-muh TREE’-tee). In that study and others like it that Egan’s lab has published for other gall species, thousands of galls are collected across the southeastern United States, and everything that emerges from the galls is studied and cataloged. Egan describes the operation, which runs almost 365 days per year, as a “factory of discovery,” and A. gallifolia was one of many mysterious specimens it has produced.

“It did not match any of the previously described species, so we documented that in our 2016 paper and raised the hypothesis that this might be a new species,” Egan said. “A year or two went by and lead author Ernesto Samaca-Saenz contacted us and offered to collaborate on determining if this lineage was, in fact, a new species.”

Samaca-Saenz is a graduate student in the UNAM lab of Zaldivar-Riveron, an expert in Allorhogas and similar predatory wasps, which can be used by farmers as biological controls for crop pests. By the time Samaca-Saenz reached out about the 2016 paper, Egan’s lab had collected a number of other undescribed specimens that they also suspected were new species of Allorhogas. The email kicked off a close collaboration that has taken Rice researchers on a number of trips to Mexico to conduct field work and science outreach in remote village schools.

While the jury is still out on exactly how A. gallifolia interacts with other species on the galls of B. treatae, Egan said he, Samaca-Saenz and Zaldivar-Riveron have discussed a number of hypotheses.

“They think it could be phytophagous, meaning it’s actually just eating plant material, or that it could be a gallmaker itself,” Egan said. “But I’m convinced that these guys are predators of caterpillars that live inside the Belonocnema galls and eat the gall plant material. I think the larval wasp eats the caterpillar and then emerges out of the side of the gall.”

Egan said it will take more research to determine whether that hypothesis is true. If it is, it would be “a whole new way of life that would be unknown to this entire genus.” But it would not be the first — or the creepiest — interaction between species that Egan and his colleagues have found.

Take 2018’s discovery, for example, that the parasitic vine Cassytha filiformis (kuh-SIHTH’-uh FIHL’-ih-form-ihs), commonly known as the love vine, targets B. treatae galls and sucks so many nutrients out of them that it mummifies the larval wasps inside. That marked the first observation of a parasitic plant attacking a gall-forming wasp, but it could not match the ghoulish weirdness of the crypt-keeper wasp they discovered in 2017.

Euderus set (yoo-DEHR’-uhs SEHT’) is so diabolical that it was named for Set, the Egyptian god who trapped, murdered and dismembered his brother in a crypt. E. set — which Egan discovered on a family vacation in Florida and later found on a tree in his front yard — lays its egg inside the gall of the Bassettia pallida (buh-SEHT’-eeuh PAL’-ih-duh) wasp. Both eggs hatch and the larvae live side by side, maturing inside the gall. When the pair are large enough to emerge as adults, E. set manipulates its step-sibling into trying to escape before its emergence hole is finished. When B. pallida’s head gets stuck in the undersized hole, E. set begins eating. Starting from the tail, it devours a tunnel through its roommate, emerging through the head to take its place in the world outside.

There are more than 1,400 known species of gall-forming wasps, and Egan said he believes there are many more species waiting to be discovered in their plant/bug-eat-bug-eat-plant corner of the world.

“We’ve focused on the gall former Belonocnema a lot, and that’s where we initially found this first Allorhogas,” he said. “When we reared out that entire community and tried to key out each of the members, A. gallifolia was one of those things where we could not narrow it down to a species. Nothing fit the description.

“Twenty-five percent of all the things we reared out of Belonocnema fit that same type of uncertainty,” Egan said. “We can’t find anything that’s ever been described like them before. Some of those, including one I have on my desk right now, are also mostly likely new species. Considering there are 90 oak species in the United States, and I have studied only three of them, this is the tip of the biodiversity iceberg.”

The research was supported by the UNAM Directorate General for Academic Personnel Affairs (IN201119) and the UNAM General Directorate of Computing and Information and Communication Technologies (LANCADUNAM-DGTIC-339).

Generosity among crows, new research


This 2014 video is called Crows: Documentary on The Intelligent World of Crows (Full Documentary).

From the University of Vienna in Austria:

Social life as a driving factor of birds’ generosity

October 22, 2020

Taking a look at generosity within the crow family reveals parallels with human evolution. Working together to raise offspring and increased tolerance towards group members contribute to the emergence of generous behavior among ravens, crows, magpies and company. Biologists found that the social life of corvids is a crucial factor for whether the birds act generously or not.

Ravens, crows, magpies and their relatives are known for their exceptional intelligence, which allows them to solve complex problems, use tools or outsmart their conspecifics. One capability, however, that we humans value highly, seems to be missing from their behavioral repertoire: generosity. Only very few species within the crow family have so far been found to act generously in experimental paradigms, while the highly intelligent ravens, for example, have demonstrated their egoistic tendencies in multiple studies. Lisa Horn of the of the Department of Behavioral and Cognitive Biology of the University of Vienna could now demonstrate, together with Jorg Massen of Utrecht University and an international team of researchers, that the social life of corvids is a crucial factor for whether the birds benefit their group members or not.

“Spontaneous generosity, without immediately expecting something in return, is a cornerstone of human society whose evolutionary foundations are still not fully understood. One hypothesis postulates that raising offspring cooperatively may have promoted the emergence of a tendency to willingly benefit group members in early human groups. Another hypothesis speculates that only increased tolerance towards group members and a reduced level of aggression made such generous behavior possible. While researchers found evidence for both hypotheses when investigating other non-human primates, results from other animal taxa have so far been missing,” explains lead author Lisa Horn.

That is why Horn and her colleagues tested generous behavior in multiple species from the crow family. Some of the tested species raise their offspring cooperatively, while others do not. Additionally, some of the species nest in close proximity with their conspecifics, thereby demonstrating their high levels of tolerance, while other species jealously guard their territories against other members of their own species. In the experiment, the birds operated a seesaw mechanism by landing on a perch, which brought food into reach of their group members. If the birds wanted to grab the food themselves, they would have had to leave the perch and the seesaw would tilt back, thereby moving the food out of reach again. Since the birds thus could not get anything for themselves the authors argued that only truly generous birds would continue to deliver food to their group members throughout multiple experimental sessions.

Raising offspring cooperatively and high tolerance as driving factors for generosity

It became evident that this behavior was displayed most strongly by these corvid species that work together to raise their offspring cooperatively. Among male birds, the researchers also found evidence for the hypothesis that high tolerance towards conspecifics is important for the emergence of generous behavior. Males from species that commonly nest in very close proximity to each other were particularly generous. These results seem to support the hypotheses that raising offspring cooperatively and increased levels of tolerance may have promoted the emergence of generous tendencies not only in humans, but also in other animals. “What fascinates me the most is that in animals that are so different from us evolutionary mechanisms very similar to the ones in our human ancestors seem to have promoted the emergence of generous behavior,” concludes Horn. More studies with different bird species, like the similarly intelligent parrots, or other animal taxa are, however, needed to further investigate these connections.

Snakes during the night, new research


This 6 September 2020 video says about itself:

12 Most Beautiful Snakes in the World

With over 3,000 snake species known to humans, it’s no surprise they come in all sorts of shapes, colors, and patterns. If you too think we spend a little too much time fearing these slithering creatures instead of admiring their natural beauty, then stick around, because today we’re bringing you The 12 Most Beautiful Snakes in the World. Seriously, #2 is so gorgeous, it’ll leave you wondering how you could ever fear one of these majestic creatures again. Okay, probably not––but you get the point.

Anyhow, strap yourselves in and let’s take a look at some of these magnificent snakes.

From the University of Houston in Texas in the USA:

How do snakes ‘see’ in the dark? Researchers have an answer

New insights explain how snakes convert infrared radiation into electrical signals

October 21, 2020

Certain species of snake — think pit vipers, boa constrictors and pythons, among others — are able to find and capture prey with uncanny accuracy, even in total darkness. Now scientists have discovered how these creatures are able to convert the heat from organisms that are warmer than their ambient surroundings into electrical signals, allowing them to “see” in the dark.

The work, published in the journal Matter, provides a new explanation for how that process works, building upon the researchers’ previous work to induce pyroelectric qualities in soft materials, allowing them to generate an electric charge in response to mechanical stress.

Researchers have known electrical activity was likely to be involved in allowing the snakes to detect prey with such exceptional skill, said Pradeep Sharma, M.D. Anderson Chair Professor of mechanical engineering at the University of Houston and corresponding author for the paper. But naturally occurring pyroelectric materials are rare, and they are usually hard and brittle. The cells in the pit organ — a hollow chamber enclosed by a thin membrane, known to play a key role in allowing snakes to detect even small temperature variations — aren’t pyroelectric materials, said Sharma, who also is chairman of the Department of Mechanical Engineering at UH.

But when he and colleagues last year reported producing pyroelectric effects in a soft, rubbery material, something clicked.

“We realized that there is a mystery going on in the snake world,” he said. “Some snakes can see in total darkness. It would be easily explained if the snakes had a pyroelectric material in their bodies, but they do not. We realized that the principle behind the soft material we had modeled probably explains it.”

Not all snakes have the ability to produce a thermal image in the dark. But those with a pit organ are able to use it as an antenna of sorts to detect the infrared radiation emanating from organisms or objects that are warmer than the surrounding atmosphere. They then process the infrared radiation to form a thermal image, although the mechanism by which that happened hasn’t been clear.

Sharma and his colleagues determined that the cells inside the pit organ membrane have the ability to function as a pyroelectric material, drawing upon the electrical voltage that is found in most cells. Through modeling, they used their proposed mechanism to explain previous experimental findings related to the process.

“The fact that these cells can act like a pyroelectric material, that’s the missing connection to explain their vision,” Sharma said.

This work was part of the Ph.D. dissertation of Faezeh Darbaniyan, first author on the paper. Additional researchers on the project include Kosar Mozaffari, a student at UH, and Professor Liping Liu of Rutgers University.

The work explains the mechanism by which the cells are able to take on pyroelectric properties, although questions remain, including how the proposed mechanism is related to the role played by the increased number of ion channels found in TRPA1 proteins. TRPA1 proteins are more abundant in the cells of pit-organ snakes than in non-pit snakes.

“Our mechanism is very robust and simple. It explains quite a lot,” Sharma said. “At the same time, it is undeniable these channels play a role as well, and we are not yet sure of the connection.”

How diabolical ironclad beetles survive cars


This 21 October 2020 video is called Diabolical Ironclad Beetle: Unlocking the secrets of its super-tough design.

From Purdue University in the USA:

This beetle can survive getting run over by a car; Engineers are figuring out how

October 21, 2020

Getting run over by a car is not a near-death experience for the diabolical ironclad beetle.

How the beetle survives could inspire the development of new materials with the same herculean toughness, engineers show in a paper published Wednesday (Oct. 21) in Nature.

These materials would be stiff but ductile like a paper clip, making machinery such as aircraft gas turbines safer and longer-lasting, the researchers said.

The study, led by engineers at the University of California, Irvine (UCI) and Purdue University, found that the diabolical ironclad beetle’s super-toughness lies in its two armorlike “elytron” that meet at a line, called a suture, running the length of the abdomen.

In flying beetles, the elytra protect wings and facilitate flight. But the diabolical ironclad beetle doesn’t have wings. Instead, the elytra and connective suture help to distribute an applied force more evenly throughout its body.

“The suture kind of acts like a jigsaw puzzle. It connects various exoskeletal blades — puzzle pieces — in the abdomen under the elytra,” said Pablo Zavattieri, Purdue’s Jerry M. and Lynda T. Engelhardt Professor of Civil Engineering.

This jigsaw puzzle comes to the rescue in several different ways depending on the amount of force applied, Zavattieri said.

To uncover these strategies, a team led by UCI professor David Kisailus first tested the limits of the beetle’s exoskeleton and characterized the various structural components involved by looking at CT scans.

Using compressive steel plates, UCI researchers found that the diabolical ironclad beetle can take on an applied force of about 150 newtons — a load of at least 39,000 times its body weight — before the exoskeleton begins to fracture.

That’s more impressive than sounds: A car tire would apply a force of about 100 newtons if running over the beetle on a dirt surface, the researchers estimate. Other terrestrial beetles the team tested couldn’t handle even half the force that a diabolical ironclad can withstand.

Zavattieri’s lab followed up these experiments with extensive computer simulations and 3D-printed models that isolated certain structures to better understand their role in saving the beetle’s life.

All of these studies combined revealed that when under a compressive load such as a car tire, the diabolical ironclad beetle’s jigsaw-like suture offers two lines of defense.

First, the interconnecting blades lock to prevent themselves from pulling out of the suture like puzzle pieces. Second, the suture and blades delaminate, which leads to a more graceful deformation that mitigates catastrophic failure of the exoskeleton. Each strategy dissipates energy to circumvent a fatal impact at the neck, where the beetle’s exoskeleton is most likely to fracture.

Even if a maximum force is applied to the beetle’s exoskeleton, delamination allows the interconnecting blades to pull out from the suture more gently. If the blades were to interlock too much or too little, the sudden release of energy would cause the beetle’s neck to snap.

It’s not yet known if the diabolical ironclad beetle has a way to heal itself after surviving a car “accident.” But knowing about these strategies could already solve fatigue problems in various kinds of machinery.

“An active engineering challenge is joining together different materials without limiting their ability to support loads. The diabolical ironclad beetle has strategies to circumvent these limitations,” said David Restrepo, an assistant professor at the University of Texas at San Antonio who worked on this project as a postdoctoral researcher in Zavattieri’s group.

In the gas turbines of aircraft, for example, metals and composite materials are joined together with a mechanical fastener. This fastener adds weight and introduces stress that could lead to fractures and corrosion.

“These fasteners ultimately decrease the performance of the system and need to be replaced every so often. But the interfacial sutures of the diabolical ironclad beetle provide a robust and more predictable failure that could help solve these problems,” said Maryam Hosseini, who worked on this project as a Ph.D. student and postdoctoral researcher in Zavattieri’s group. Hosseini is now an engineering manager at Procter & Gamble Corp.

UCI researchers built a carbon fiber composite fastener mimicking a diabolical ironclad beetle’s suture. Purdue researchers found through loading tests that this fastener is just as strong as a standard aerospace fastener, but significantly tougher.

“This work shows that we may be able to shift from using strong, brittle materials to ones that can be both strong and tough by dissipating energy as they break. That’s what nature has enabled the diabolical ironclad beetle to do,” Zavattieri said.

This research is financially supported by the Air Force Office of Scientific Research and the Army Research Office through the Multi-University Research Initiative (award number FA9550-15-1-0009). The study used resources at the Advanced Light Source, a U.S. Department of Energy Office of Science User Facility.

How barn owls fly, new research


This 21 October 2020 video is called Lily the Barn Owl Reveals How Birds Fly in Gusty Winds.

From the University of Bristol in England:

Lily the barn owl reveals how birds fly in gusty winds

Newly discovered avian suspension system has implications for bio-inspired aircraft

October 21, 2020

Scientists from the University of Bristol and the Royal Veterinary College have discovered how birds are able to fly in gusty conditions — findings that could inform the development of bio-inspired small-scale aircraft.

“Birds routinely fly in high winds close to buildings and terrain — often in gusts as fast as their flight speed. So the ability to cope with strong and sudden changes in wind is essential for their survival and to be able to do things like land safely and capture prey,” said Dr Shane Windsor from the Department of Aerospace Engineering at the University of Bristol.

“We know birds cope amazingly well in conditions which challenge engineered air vehicles of a similar size but, until now, we didn’t understand the mechanics behind it,” said Dr Windsor.

The study, published in Proceedings of the Royal Society B, reveals how bird wings act as a suspension system to cope with changing wind conditions. The team used an innovative combination of high-speed, video-based 3D surface reconstruction, computed tomography (CT) scans, and computational fluid dynamics (CFD) to understand how birds ‘reject’ gusts through wing morphing, i.e. by changing the shape and posture of their wings.

In the experiment, conducted in the Structure and Motion Laboratory at the Royal Veterinary College, the team filmed Lily, a barn owl, gliding through a range of fan-generated vertical gusts, the strongest of which was as fast as her flight speed. Lily is a trained falconry bird who is a veteran of many nature documentaries, so wasn’t fazed in the least by all the lights and cameras.

“We began with very gentle gusts in case Lily had any difficulties, but soon found that — even at the highest gust speeds we could make — Lily was unperturbed; she flew straight through to get the food reward being held by her trainer, Lloyd Buck,” commented Professor Richard Bomphrey of the Royal Veterinary College.

“Lily flew through the bumpy gusts and consistently kept her head and torso amazingly stable over the trajectory, as if she was flying with a suspension system. When we analysed it, what surprised us was that the suspension-system effect wasn’t just due to aerodynamics, but benefited from the mass in her wings. For reference, each of our upper limbs is about 5% of our body weight; for a bird it’s about double, and they use that mass to effectively absorb the gust,” said lead-author Dr Jorn Cheney from the Royal Veterinary College.

“Perhaps most exciting is the discovery that the very fastest part of the suspension effect is built into the mechanics of the wings, so birds don’t actively need to do anything for it to work. The mechanics are very elegant. When you strike a ball at the sweetspot of a bat or racquet, your hand is not jarred because the force there cancels out. Anyone who plays a bat-and-ball sport knows how effortless this feels. A wing has a sweetspot, just like a bat. Our analysis suggests that the force of the gust acts near this sweetspot and this markedly reduces the disturbance to the body during the first fraction of a second. The process is automatic and buys just enough time for other clever stabilising processes to kick in,” added Dr Jonathan Stevenson from the University of Bristol.

Mysterious young sea stars, new research


Valvaster striatus sea stars

From the Smithsonian Tropical Research Institute in Panama, 13 October 2020:

Sea star’s ability to clone itself may empower this mystery globetrotter

October 13, 2020

Summary: The identity of wild cloning sea star larvae has been a mystery since they were first documented in the Caribbean. The most commonly collected cloning species was thought to belong to the Oreasteridae, on the basis of similarity with sequences from Oreaster reticulatus and Oreaster clavatus.

For decades, biologists have captured tiny sea star larvae in their nets that did not match the adults of any known species. A Smithsonian team recently discovered what these larvae grow up to be and how a special superpower may help them move around the world. Their results are published online in the Biological Bulletin.

“Thirty years ago, people noticed that these asteroid starfish larvae could clone themselves, and they wondered what the adult form was,” said staff scientist Rachel Collin at the Smithsonian Tropical Research Institute (STRI). “They assumed that because the larvae were in the Caribbean the adults must also be from the Caribbean.”

Scientists monitor larvae because the larvae can be more sensitive to physical conditions than the adults and larval dispersal has a large influence on the distribution of adult fishes and invertebrates. Collin’s team uses a technique called DNA barcoding to identify plankton. They determine the DNA sequence of an organism, then look for matches with a sequence from a known animal in a database.

“This mystery species was one of the most common in our samples from the Caribbean coast of Panama,” Collin said. “We knew from people’s studies that the DNA matched sequences from similar larvae across the Caribbean and it matched unidentified juvenile starfish caught in the Gulf of Mexico — but no one had found a match to any known adult organism in the Caribbean. So we decided to see if the DNA matched anything in the global ‘Barcode of Life’ data base.”

“That’s when we got a match with Valvaster striatus, a starfish that was thought to be found only in the Indo West Pacific,” Collin said. “The is the first-ever report of this species in the Atlantic Ocean. We could not have identifed it if Gustav Paulay from the University of Florida didn’t have DNA sequences from invertebrates on the other side of the world.”

But why are the larvae common in the Caribbean if adult Valvaster starfish have never been found here? Are the adult starfish hidden inside Caribbean reefs, or are the larvae arriving from the other side of the world?

V. striatus is widespread but rare in the western Pacific. The few reports from collectors and the confirmed photos on iNaturalist range from the Indian Ocean to Guam and Hawaii. These starfish live deep in the reef matrix, only coming out at night. So, it is possible that there are adults in the Caribbean that have never been seen. But the other possibility, that the ability to clone themselves may allow them to spread around the world, is also intriguing.

“It’s possible that the ability of the larvae to clone themselves is not just a clever way to stay forever young,” Collin said. “There’s a natural barrier that keeps organisms from the western Pacific and the Indian ocean from crossing the Atlantic to the Caribbean. After they make it around the tip of Africa, they are met by a cold current that presumably kills tropical species.”

“Just how cloning could help them get through the barrier is still not known, but it’s intriguing that another sea star species from the Indo West Pacific that was collected for the first time in the Caribbean in the 1980s also has cloning larvae,” Collin said.