Long-tailed tits and mathematics, new research


This 15 April 2020 video says about itself:

This footage is recorded in Oxfordshire in England UK, in a bramble thicket. The nests are always about 1.0-1.5m from the ground and in a very prickly place like brambles, blackthorn or gorse.

These birds build a nest that is so intricate and painstaking that it takes much longer to construct than most birds’ nests and so they start very early in Spring, in March. It can take two or three weeks to finish. Several thousand feathers of other birds are used to line the nest.

The nest is made of lichens, moss and spider web threads. This makes it very strong and stretchy so that as the youngsters grow inside so the nest expands too. It needs to – they can have seven youngsters in the nest at once.

From the University of Sheffield in England:

Mathematical patterns developed by Alan Turing help researchers understand bird behavior

August 11, 2020

Scientists from the University of Sheffield have used mathematical modelling to understand why flocks of long-tailed tits segregate themselves into different parts of the landscape.

The team tracked the birds around Sheffield’s Rivelin Valley which eventually produced a pattern across the landscape, using maths helped the team to reveal the behaviours causing these patterns.

The findings, published in the Journal of Animal Ecology, show that flocks of long-tailed tits are less likely to avoid places where they have interacted with relatives and more likely to avoid larger flocks, whilst preferring the centre of woodland.

It was previously unknown why flocks of long-tailed tits live in separate parts of the same area, despite there being plenty of food to sustain multiple flocks and the birds not showing territorial behaviour.

The equations used to understand the birds are similar to those developed by Alan Turing to describe how animals get their spotted and striped patterns. Turing’s famous mathematics indicates if patterns will appear as an animal grows in the womb, here it’s used to find out which behaviours lead to the patterns across the landscape.

Territorial animals often live in segregated areas that they aggressively defend and stay close to their den. Before this study, these mathematical ideas had been used to understand the patterns made by territorial animals such as coyotes, meerkats and even human gangs. However, this study was the first to use the ideas on non-territorial animals with no den pinning them in place.

Natasha Ellison, PhD student at the University of Sheffield who led the study, said: “Mathematical models help us understand nature in an extraordinary amount of ways and our study is a fantastic example of this.”

“Long-tailed tits are too small to be fitted with GPS trackers like larger animals, so researchers follow these tiny birds on foot, listening for bird calls and identifying birds with binoculars. The fieldwork is extremely time consuming and without the help of these mathematical models these behaviours wouldn’t have been discovered.”

Big dinosaur age crocodile Deinosuchus


This July 2019 video says about itself:

Deinosuchus Animation Preview

Locomotion and behavioral extrapolations of large crocodilian, genotype Deinosuchus. Highly dangerous aquatic predator.

From ScienceDaily:

New study confirms the power of Deinosuchus and its ‘teeth the size of bananas’

August 10, 2020

A new study, revisiting fossil specimens from the enormous crocodylian, Deinosuchus, has confirmed that the beast had teeth “the size of bananas,” capable to take down even the very largest of dinosaurs.

And, it wasn’t alone!

The research, published in the Journal of Vertebrate Paleontology, also reveals various kinds of “terror crocodile.” Two species, entitled Deinosuchus hatcheri and Deinosuchus riograndensis lived in the west of America, ranging from Montana to northern Mexico. Another, Deinosuchus schwimmeri, lived along the Atlantic coastal plain from New Jersey to Mississippi. At the time, North America was cut in half by a shallow sea extending from the Arctic Ocean south to the present-day Gulf of Mexico.

Ranging in up to 33 feet in length Deinosuchus, though, has been known to be one of the largest, if not the largest, crocodylian genera ever in existence. It was the largest predator in its ecosystem, outweighing even the largest predatory dinosaurs living alongside them between 75 and 82 million years ago.

From previous studies of cranial remains and bite marks on dinosaur fossil bones, paleontologists have long speculated that the massive beasts preyed on dinosaurs.

Now this new study, led by Dr Adam Cossette sheds new light on the monstrous creature and has further confirmed that it most certainly had the head size and crushing jaw strength to do just that.

“Deinosuchus was a giant that must have terrorized dinosaurs that came to the water’s edge to drink,” says Dr Cossette, from the New York Institute of Technology College of Osteopathic Medicine at Arkansas State University. “Until now, the complete animal was unknown. These new specimens we’ve examined reveal a bizarre, monstrous predator with teeth the size of bananas.”

Co-author Stephanie Drumheller-Horton, a paleontologist at the University of Tennessee, added: “Deinosuchus seems to have been an opportunistic predator, and given that it was so enormous, almost everything in its habitat was on the menu.”

“We actually have multiple examples of bite marks made by D. riograndensis and a species newly described in this study, D. schwimmeri, on turtle shells and dinosaur bones.”

In spite of the genus’s name, which means “terror crocodile,” they were actually more closely related to alligators. Based on its enormous skull, it looked like neither an alligator nor a crocodile. Its snout was long and broad, but inflated at the front around the nose in a way not seen in any other crocodylian, living or extinct. The reason for its enlarged nose is unknown.

“It was a strange animal,” says Brochu. “It shows that crocodylians are not ‘living fossils’ that haven’t changed since the age of dinosaurs. They’ve evolved just as dynamically as any other group.”

Deinosuchus disappeared before the main mass extinction at the end of the age of dinosaurs (Meozoic). The reason for its extinction remains unknown. From here, the authors call for me studies to further understand Deinosuchus.

“It had two large holes are present at the tip of the snout in front of the nose,” Dr Cossette says.

“These holes are unique to Deinosuchus and we do not know what they were for, further research down the line will hopefully help us unpick this mystery and we can learn further about this incredible creature.”

Panama Canal island lizards, new research


This 2011 video says about itself:

Bunch off large lizards on a small Island near Pedasi, Panama

From the Smithsonian Tropical Research Institute in Panama:

Biodiversity may limit invasions: Lessons from lizards on Panama Canal islands

August 10, 2020

Summary: Introduced species can become invasive, damaging ecosystems and disrupting economies through explosive population growth. One mechanism underlying population expansion in invasive populations is ‘enemy release’, whereby the invader experiences relaxation of agonistic interactions with other species, including parasites.

When the U.S. flooded Panama’s Chagres River valley in 1910, Gatun Lake held the record as the world’s biggest reservoir. This record was surpassed, but researchers at the Smithsonian Tropical Research Institute (STRI), who are now studying invading lizards on the tiny islands that dot the lake, discovered that islands with native lizards act as another kind of reservoir, harboring the parasites that control invaders. The study, published in the journal Biology Letters, is valuable experimental evidence that biodiversity is better, making ecosystems more resistant to invasion.

As part of another study to find out how many generations it takes for slender anole lizards (Anolis apletophallus) to adapt to climate change, a research team led by Christian Cox, a visiting scientist at STRI from Florida International University, and Mike Logan from the University of Nevada, Reno, transplanted lizards from the tropical forest on the mainland to the islands, which tend to be hotter and drier. Before the transplant, they did a general health check of the lizards that included counting the number of parasites (mites) on their bodies.

When they came back several times during the next two years to see how the lizards were doing in their new habitats, they recounted the number of mites.

“We found that on the islands with no resident species of anole lizard, the slender anole lizards that were transplanted to the islands lost their mites within a single generation, and the mites are still gone several generations later (up until the present),” Cox said. “Indeed, individual founding lizards that had mites during the initial transplant had no mites when they were later recaptured. In contrast, anole lizards that were transplanted to an island with another resident (native) species of anole lizard kept their mites for three generations, and some of the founders on the two-species island never lost their mites.”

“Our study turned out to be a large-scale experimental test of the enemy release hypothesis,” said Logan, who did this work as a three-year STRI/Tupper postdoctoral fellow. “Often, when an invasive animal shows up in a new place, all of its pathogens and parasites are left behind or do not survive, giving it an extra survival advantage in the new place: thus the term enemy release.”

The team also found that the two-species island had lower density and lower biomass per unit area of the invasive lizard species, indicating that the continued presence of the mites may be keeping their populations under control.

“Our study is a clear example of something that conservationists have been trying to communicate to the public for some time,” Logan said. “Diverse native communities sometimes function as ‘enemy reservoirs’ for parasites and diseases the keep down the numbers of invaders.”

Funding for this study was provided by the Smithsonian Institution, Georgia Southern University, the Theodore Roosevelt Memorial Foundation and the American Museum of Natural History.

Tanystropheus Triassic reptiles, marine, not on land


This 7 August 2020 video says about itself:

For more than a hundred years, the fossil of the Tanystropheus has puzzled scientists. The strange reptile — resembling a real-life Loch Ness Monster or a prehistoric crocodile crossed with a giraffe — was first described in 1852 and first reconstructed in 1973.

Paleontologists have long known that the species once lived in Switzerland’s Monte San Giorgio basin during the Middle Triassic period (about 242 million years ago). They also knew the bizarre-looking 20-foot creature had a remarkably long neck, which at 10 feet long was half of its entire length. But the remaining details surrounding the remained fuzzy and have been much debated. Did these #animals live on land or in the water? What did their young look like? And how did they interact with the other species in their environment? No one knew — until now.

Scientists used computed tomography (CT) scan technology to digitally reconstruct the crushed skulls of the fossils, which revealed evidence that these reptiles were water-dwelling, according to new research published in Current Biology.

From the Field Museum in the USA:

Fossil mystery solved: Super-long-necked reptiles lived in the ocean, not on land

Twenty-foot-long specimens described as separate species from their cousins, named after mythology’s Hydra

August 6, 2020

A fossil called Tanystropheus was first described in 1852, and it’s been puzzling scientists ever since. At one point, paleontologists thought it was a flying pterosaur, like a pterodactyl, and that its long, hollow bones were phalanges in the finger that supported the wing. Later on, they figured out that those were elongated neck bones, and that it was a twenty-foot-long reptile with a ten-foot neck: three times as long as its torso. Scientists still weren’t sure if it lived on land or in the water, and they didn’t know if smaller specimens were juveniles or a completely different species — until now. By CT-scanning the fossils’ crushed skulls and digitally reassembling them, researchers found evidence that the animals were water-dwelling, and by examining the growth rings in bones, determined that the big and little Tanystropheus were separate species that could live alongside each other without competing because they hunted different prey.

“I’ve been studying Tanystropheus for over thirty years, so it’s extremely satisfying to see these creatures demystified,” says Olivier Rieppel, a paleontologist at the Field Museum in Chicago and one of the authors of a new paper in Current Biology detailing the discovery.

Tanystropheus lived 242 million years ago, during the middle Triassic. On land, dinosaurs were just starting to emerge, and the sea was ruled by giant reptiles. For a long time, though, scientists weren’t sure whether Tanystropheus lived on land or in the water. Its bizarre body didn’t make things clear one way or the other.

“Tanystropheus looked like a stubby crocodile with a very, very long neck,” says Rieppel. The larger specimens were twenty feet long, with their necks making up ten feet of that length. Oddly for animals with such long necks, they only had thirteen neck vertebrae, just really elongated. (We see the same thing with giraffes, which have only seven neck bones, just like humans.) And their necks were rather inflexible, reinforced with extra bones called cervical ribs.

In the same region where many of the big Tanystropheus fossils were found, in what’s now Switzerland, there were also fossils from similar-looking animals that were only about four feet long. So not only were scientists unsure if these were land-dwellers or marine animals, but they also didn’t know if the smaller specimens were juveniles, or a separate species from the twenty-footers.

To solve these two long-standing mysteries, the researchers used newer technologies to see details of the animals’ bones. The large Tanystropheus fossils’ skulls had been crushed, but Stephan Spiekman, the paper’s lead author and a researcher at the University of Zurich, was able to take CT scans of the fossil slabs and generate 3D images of the bone fragments inside.

“The power of CT scanning allows us to see details that are otherwise impossible to observe in fossils,” says Spiekman. “From a strongly crushed skull we have been able to reconstruct an almost complete 3D skull, revealing crucial morphological details.”

The skulls had key features, including nostrils on top of the snout like a crocodile’s, that suggested Tanystropheus lived in the water. It probably lay in wait, waiting for fish and squid-like animals to swim by, and then snagged them with its long, curved teeth. It may have come to land to lay eggs, but overall, it stayed in the ocean.

Rieppel wasn’t surprised that evidence pointed to a water-dwelling Tanystropheus. “That neck doesn’t make sense in a terrestrial environment,” he says. “It’s just an awkward structure to carry around.”

So that answered one question, about where Tanystropheus lived. To learn whether the small specimens were juveniles or a separate species, the researchers examined the bones for signs of growth and aging.

“We looked at cross sections of bones from the small type and were very excited to find many growth rings. This tells us that these animals were mature,” says Torsten Scheyer, the study’s senior author and a researcher at University of Zurich.

“The small form is an adult, which basically sealed the case,” says Rieppel. “It’s proven now that these are two species.” The researchers named the larger one Tanystropheus hydroides, after the long-necked hydras in Greek mythology. The small form bears the original name Tanystropheus longobardicus.

“For many years now we have had our suspicions that there were two species of Tanystropheus, but until we were able to CT scan the larger specimens we had no definitive evidence. Now we do,” says Nick Fraser, Keeper of Natural Sciences at National Museums Scotland and a co-author of the paper. “It is hugely significant to discover that there were two quite separate species of this bizarrely long-necked reptile who swam and lived alongside each other in the coastal waters of the great sea of Tethys approximately 240 million years ago.”

The animals’ different sizes, along with cone-shaped teeth in the big species and crown-shaped teeth in the little species, meant they probably weren’t competing for the same prey.

“These two closely related species had evolved to use different food sources in the same environment,” says Spiekman. “The small species likely fed on small shelled animals, like shrimp, in contrast to the fish and squid the large species ate. This is really remarkable, because we expected the bizarre neck of Tanystropheus to be specialized for a single task, like the neck of a giraffe. But actually, it allowed for several lifestyles. This completely changes the way we look at this animal.”

This “splitting up” of a habitat to accommodate two similar species is called niche partitioning. “Darwin focused a lot on competition between species, and how competing over resources can even result in one of the species going extinct,” says Rieppel. “But this kind of radical competition happens in restricted environments like islands. The marine basins that Tanystropheus lived in could apparently support niche partitioning. It’s an important ecological phenomenon.”

“Tanystropheus is an iconic fossil and has always been,” adds Rieppel. “To clarify its taxonomy is an important first step to understanding that group and its evolution.”

Tasmanian devils may help in fighting cancer


This 2008 video says about itself:

The odd Tasmanian devil has a huge head to power its massive jaws. It also has an unsettling array of sounds.

From Washington State University in the USA:

Tasmanian devil research offers new insights for tackling cancer in humans

August 6, 2020

A rare, transmissible tumor has brought the iconic Tasmanian devil to the brink of extinction, but new research by scientists at Washington State University and the Fred Hutchinson Cancer Research Center in Seattle indicates hope for the animals’ survival and possibly new treatment for human cancers.

The study, published in Genetics on Aug. 1, found a single genetic mutation that leads to reduced growth of a transmissible cancer in Tasmanian devils in the wild.

“This gene is implicated in human prostate and colon cancers,” said Andrew Storfer, professor of biological sciences at WSU. “While the findings hold the most immediate promise to help save the world’s few remaining Tasmanian devils, these results could also someday translate to human health.”

The research team, led by Storfer and Mark Margres, now a postdoctoral fellow at Harvard University, studied the genomes of cases of devil facial tumor disease, or DFTD, that regressed spontaneously — that is, the cancer began disappearing on its own.

They were surprised to find the mutation contributing to tumor regression doesn’t change the gene function but instead, turns on a gene that slows cell growth in the tumor. At least, it behaves that way in the lab.

Current human cancer therapies focus on removing every trace of a tumor, often through toxic or debilitating treatments, said David Hockenbery, a cancer biologist at Fred Hutch who contributed to the study.

“If there were ways that tumors could be tricked into regressing without having to administer cytotoxic drugs or deforming surgeries, it would be a major advance,” he said.

While infections cause up to 20 percent of all human cancers — such as gastric cancer from Helicobacter pylori and cervical cancer from human papillomavirus — for Tasmanian devils, the cancer is the infection.

DFTD spreads between the animals when they bite each other during common social behaviors. Since the mid-1990s, the disease has decimated the natural population of the carnivorous marsupials, which are now found only on the island state of Tasmania, off the southeastern coast of Australia.

Storfer’s lab leads a National Institutes of Health-funded team of researchers from the U.S. and Australia to improve conservation efforts for Tasmanian devils and increase understanding of the co-evolution of the tumor and its host.

Though ferocious with each other, Tasmanian devils take mild handling by people without much fuss, making it easy for investigators to humanely capture the animals, collect tissue samples and tag them for monitoring before release back into the wild.

As the researchers work to save the devils, they also have an unprecedented opportunity to watch tumors naturally evolve and sometime regress without drugs or surgery.

“Although this disease is largely fatal, we’re seeing tumors just disappear from an increasing number of individual animals,” Storfer said.

The team is looking at the effects of other promising mutations in regressed tumors as well.

“We hope to learn something that could be applied to understanding and possibly treating a number of human cancers in the future,” Storfer said.

This research was supported by the National Institutes of Health, the National Science Foundation and the Washington Research Foundation.

Herbicides threaten kangaroos, new research


This 2015 video says about itself:

Tammar Wallabies

A small wallaby native to South Australia and Western Australia. They were staying close to the dense undergrowth. Notice how the ears can move independently. This video was taken in southwest Western Australia.

From the University of Melbourne in Australia:

Herbicide harming marsupial health and development, research finds

Atrazine impacts reproduction in kangaroos and wallabies

August 6, 2020

Summary: Researchers exposed the adult female tammar wallabies to atrazine contaminated water throughout pregnancy, birth and lactation to help establish the extent of harm being caused by the chemical. They then examined the reproductive development of their young by assessing their growth and development to establish that the herbicide is causing major abnormalities in the male reproductive system in many animals.

The health of wallabies and kangaroos is being affected by the herbicide, atrazine, which is used widely in Australia on cereal crops and in forestation to prevent weeds, according to new research.

Atrazine, which has been banned in the European Union since 2003, may be impacting reproduction in marsupials, the University of Melbourne study found, published today in Reproduction, Fertility and Development.

“Exposures to atrazine is causing major abnormalities in the male reproductive system in many animals, triggering male sterility or even male-to-female sex reversal in frogs,” Professor in Genetics Andrew Pask said.

“With the marsupial’s unique mode of reproduction and the young completing their development in the pouch, mothers are unknowingly passing the toxins on in their breast milk, exposing their young to environmental toxins.”

The study is the first time the impacts of pesticides have been investigated in any marsupial and show that they are able to affect reproductive development.

The research found that concentrations of atrazine have been recorded at disturbingly high levels in Victorian rivers and Tasmanian streams immediately after forestry spraying.

Kangaroos and wallabies are at high risk because they eat the sprayed crops and drink from contaminated water resources where chemicals such as atrazine accumulate from runoff.

Atrazine affects a broad range of animals from mammals such as rats to amphibians, reptiles and even fish.

With marsupials already experiencing devastating population declines across Australia, and 21 per cent of native mammals currently threatened with extinction, researchers say the potential impacts of environmental toxins are of major concern.

Researchers exposed the adult female tammar wallabies to atrazine contaminated water throughout pregnancy, birth and lactation to help establish the extent of harm being caused by the chemical.

They then examined the reproductive development of their young by assessing their growth and development.

Lead author on the research and PhD student Laura Cook said it is hoped the study will lead to more stringent guidelines around the use of atrazine in Australia.

“Endocrine-disrupting chemicals, such as atrazine, have the ability to impact development and increase disease susceptibility,” she said.

“With increased habitat destruction, marsupials are being pushed onto farmland, attracted to the food resources and rare permanent water sources where they may be vulnerable to agricultural contaminants, such as pesticides.”

New Guinea, world’s most diverse flowers


This 2014 video says about itself:

Some of the spectacular diverse plant life of the Southern Highlands of Papua New Guinea.

From the University of Zurich in Zwitserland:

New Guinea has the world’s richest island flora

August 5, 2020

Summary: New Guinea is the most floristically diverse island in the world, an international collaboration has shown. The study presents a list of almost 14,000 plant species, compiled from online catalogues and verified by plant experts. The results are invaluable for research and conservation, and also underline the importance of expert knowledge in the digital era.

Almost 20 times the size of Switzerland, New Guinea is the world’s largest tropical island. It features a complex mosaic of ecosystems from lowland jungles to high-elevation grasslands with peaks higher than Mont Blanc. Botanists have long known that this mega-diverse wilderness area is home to a large number of plant species. Efforts to identify and name thousands of plants collected in New Guinea and archived in herbaria all over the world have been ongoing since the 17th century.

However, since researchers have worked mostly independently from each other, a great uncertainty remains as to the exact number of plant species, with conflicting estimates ranging from 9,000 to 25,000. “Compared to other areas like Amazonia, for which plant checklists were recently published, New Guinea remained the ‘Last Unknown’,” says Rodrigo Cámara-Leret, a postdoctoral researcher in the lab of Prof. Jordi Bascompte in the UZH Department of Evolutionary Biology and Environmental Studies. Under his lead, 99 scientists from 56 institutions and 19 countries have now built the first expert-verified checklist for the 13,634 vascular plant species of New Guinea and its surrounding islands.

Merging databases and human knowledge

The researchers began their large-scale collaborative effort by compiling a list of plant names from online catalogues, institutional repositories and datasets curated by taxonomists. After standardizing the scientific names, 99 experts on New Guinea flora checked almost 25,000 species names derived from over 700,000 individual specimens. For this, they reviewed the list of original names in their plant family of expertise and assessed whether these names were correctly assigned in the online platforms. Finally, an independent comparison was performed between the list accepted by experts and a list contained in Plants of the World Online for New Guinea.

Tremendous, mostly endemic plant diversity

The resulting checklist contains 13,634 plants, demonstrating that New Guinea has the world’s richest island flora, with about 20% more species than Madagascar or Borneo. By far the most species-rich family are the orchids and almost a third of the species are trees. One particularly remarkable finding is that 68% of the plants are endemic, they are only found in the region. “Such high endemic species richness is unmatched in tropical Asia,” says Cámara-Leret, “It means that Indonesia and Papua New Guinea, the two states into which the island is divided, have a unique responsibility for the survival of this irreplaceable biodiversity.”

Foundation for research and protection

The new authoritative checklist will improve the accuracy of biogeographic and ecological studies, help focus DNA sequencing on species-rich groups with high endemism, and facilitate the discovery of more species by taxonomists. Thousands of specimens remain unidentified in the collections and many unknown species have yet to be discovered in the wild. “We estimate that in the next 50 years, 3,000 to 4,000 species will be added,” says Michael Kessler, co-author of the study and scientific curator of the Botanical Garden of the University of Zurich. These efforts will be important for conservation planning and modelling the impact of changes in climate and land use.

The collaboration also underscores that expert knowledge is still essential in the digital era, reliance on online platforms alone would have erroneously inflated species counts by one fifth. However, many of the New Guinea plants experts are already or soon to be retired, and almost half of them are non-residents. The researchers therefore advocate building a critical mass of resident plant taxonomists.

Policy-wise, the study shows that long-term institutional and financial support is critical if significant advances are to be made over the next decades. “Our work demonstrates that international collaborative efforts using verified digital data can rapidly synthesize biodiversity information. This can serve as a model for accelerating research in other hyper-diverse areas such as Borneo,” says Cámara-Leret. “Such initiatives pave the way for the grand challenge of conserving the richest island flora of the world.”

Tuatara reptiles’ genome, similar to mammals


This January 2020 video says about itself:

Today, Department of Conservation rangers Lee and Joyce are in search of a rare animal found only on an island in New Zealand. Follow them on their quest to find and breed two Tuataras, an ancient reptile that predates the dinosaurs.

From Northern Arizona University in the USA:

Dinosaur relative’s genome linked to mammals: Curious genome of ancient reptile

August 5, 2020

A lizard-like creature whose ancestors once roamed the Earth with dinosaurs and today is known to live for longer than 100 years may hold clues to a host of questions about the past and the future.

In a study published Aug. 5 in Nature, an interdisciplinary, international team of researchers, in partnership with Maori tribe Ngatiwai, sequenced, assembled and analyzed the complete genome of the Sphenodon punctatus, or the tuatara, a rare reptile whose ancestors once roamed the earth with dinosaurs. It hasn’t changed much in the 150 million to 250 million years since then.

“We found that the tuatara genome has accumulated far fewer DNA substitutions over time than other reptiles, and the molecular clock for tuataras ticked at a much slower speed than squamates, although faster than turtles and crocodiles, which are the real molecular slowpokes,” said co-author Marc Tollis, an assistant professor in the School of Informatics, Computing, and Cyber Systems at Northern Arizona University. “This means in terms of the rate of molecular evolution, tuataras are kind of the Toyota Corolla — nothing special but very reliable and persistently ticking away over hundreds of millions of years.”

Tuatara have been out on their own for a staggering amount of time, with prior estimates ranging from 150-250 million years, and with no close relatives the position of tuatara on tree of life has long been contentious. Some argue tuatara are more closely related to birds, crocodiles and turtles, while others say they stem from a common ancestor shared with lizards and snakes. This new research places tuatara firmly in the branch shared with lizards and snakes, but they appear to have split off and been on their own for about 250 million years — a massive length of time considering primates originated about 65 million years ago, and hominids, from which humans descend, originated approximately six million years ago.

“Proving the phylogenetic position of tuatara in a robust way is exciting, but we see the biggest discovery in this research as uncovering the genetic code and beginning to explore aspects of the biology that makes this species so unique, while also developing new information that will help us better conserve this taonga or special treasure,” said lead author Neil Gemmell, a professor at the University of Otago.

One area of particular interest is to understand how tuataras, which can live to be more than 100 years old, achieve such longevity. Examining some of the genes implicated in protecting the body from the ravages of age found that tuatara have more of these genes than any other vertebrate species thus far examined, including humans. This could offer clues into how to increase humans’ resistance to the ailments that kill humans.

But the genome, and the tuatara itself, has so many other unique features all on its own. For one, scientists have found tuatara fossils dating back 150 million years, and they look exactly the same as the animals today. The fossil story dates the tuatara lineage to the Triassic Period, when dinosaurs were just starting to roam the Earth.

“The tuatara genome is really a time machine that allows us to understand what the genetic conditions were for animals that were vying for world supremacy hundreds of millions of years ago,” he said. “A genome sequence from an animal this ancient and divergent could give us a better idea about what the ancestral amniote genome might have looked like.”

While modern birds are the descendants of dinosaurs, they are less suitable for this type of research because avian genomes have lost a significant amount of DNA since diverging from their dinosaur ancestors.

But the tuataras, which used to be spread throughout the world, have other unusual features. Particularly relevant to this research is the size of its genome; the genome of this little lizard has 5 billion bases of DNA, making it 67 percent larger than a human genome. Additionally, tuataras have temperature-based sex determination, which means the ratio of males to females in a clutch of eggs depends on the temperatures at which they are incubated. They also have a pronounced “third eye” — a light sensory organ that sticks through the top of their skulls. Mammals’ skulls have completely covered the third eye, though they still contain the pineal gland underneath, which helps maintain circadian rhythms.

The tuatara also is unique in that it is sacred to the Maori people. This research, for all the scientific knowledge that came from it, was groundbreaking for its collaboration with the Indigenous New Zealanders. The purpose was to ensure the research aligned with and respected the importance of the tuatara in their culture, which has never been done before in genomic research.

“Tuatara are a taonga, and it’s pleasing to see the results of this study have now been published,” Ngatiwai Trust Board resource management unit manager Alyx Pivac said. “Our hope is that this is yet another piece of information that will help us understand tuatara and aid in the conservation of this special species. We want to extend a big mihi to all of those who have been involved in this important piece of work.”

With the genome now sequenced, the international science community has a blueprint through which to examine the many unique features of tuatara biology, which will aid human understanding of the evolution of the amniotes, a group that includes birds, reptiles and mammals.

Spacecraft discovers new emperor penguin colonies


This 5 August 2020 video says about itself:

Satellites find new colonies of Emperor penguins

Satellites have discovered 11 previously unknown emperor penguin colonies in Antarctica. WION’s Palki Sharma tells you why this is a major discovery.

At the beginning of the video, also Adelie penguins.

From the British Antarctic Survey:

Scientists discover new penguin colonies from space

August 4, 2020

A new study using satellite mapping technology reveals there are nearly 20% more emperor penguin colonies in Antarctica than was previously thought. The results provide an important benchmark for monitoring the impact of environmental change on the population of this iconic bird.

Reporting this week in the journal Remote Sensing in Ecology and Conservation, the authors describe how they used images from the European Commission’s Copernicus Sentinel-2 satellite mission to locate the birds. They found 11 new colonies, three of which were previously identified but never confirmed. That takes the global census to 61 colonies around the continent.

Emperor penguins need sea ice to breed and are located in areas that are very difficult to study because they are remote and often inaccessible with temperatures as low as 50°C (58 degrees Fahrenheit). For the last 10 years, British Antarctic Survey (BAS) scientists have been looking for new colonies by searching for their guano stains on the ice.

Lead author Dr Peter Fretwell, a geographer at BAS says:

“This is an exciting discovery. The new satellite images of Antarctica’s coastline have enabled us to find these new colonies. And whilst this is good news, the colonies are small and so only take the overall population count up by 5-10% to just over half a million penguins or around 265,500 — 278,500 breeding pairs.”

Emperor penguins are known to be vulnerable to loss of sea ice, their favoured breeding habitat. With current projections of climate change, this habitat is likely to decline. Most of the newly found colonies are situated at the margins of the emperors’ breeding range. Therefore, these locations are likely to be lost as the climate warms.

Dr Phil Trathan, Head of Conservation Biology at BAS, has been studying penguins for the last three decades. He says:

“Whilst it’s good news that we’ve found these new colonies, the breeding sites are all in locations where recent model projections suggest emperors will decline. Birds in these sites are therefore probably the ‘canaries in the coalmine’ — we need to watch these sites carefully as climate change will affect this region.”

The study found a number of colonies located far offshore, situated on sea ice that has formed around icebergs that had grounded in shallow water. These colonies, up to 180 km offshore, are a surprising new finding in the behaviour of this increasingly well-known species.

The research was funded by UKRI-NERC as part of the Wildlife from Space project.

Sea angels, sharks or rays?


This April 2020 video from California in the USA is called Angel Shark Quest | JONATHAN BIRD’S BLUE WORLD.

From the University of Vienna in Austria:

Between shark and ray: The evolutionary advantage of the sea angels

Threatened with extinction despite perfect adaptation

August 4, 2020

Summary: Angel sharks are sharks, but with their peculiarly flat body they rather resemble rays. An international research team has now investigated the origin of this body shape. The results illustrate how these sharks evolved into highly specialized, exclusively bottom-dwelling ambush predators and thus also contribute to a better understanding of their threat from environmental changes

The general picture of a shark is that of a fast and large ocean predator. Some species, however, question this image — for example angel sharks. They have adapted to a life on the bottom of the oceans, where they lie in wait for their prey. In order to be able to hide on or in the sediment, the body of angel sharks became flattened in the course of their evolution, making them very similar to rays, which are closely related to sharks.

Flattened body as indication for a successful lifestyle

The oldest known complete fossils of angel sharks are about 160 million years old and demonstrate that the flattened body was established early in their evolution. This also indicates that these extinct angel sharks already had a similar lifestyle as their extant relatives — and that this lifestyle obviously was very successful.

Angel sharks are found all over the world today, ranging from temperate to tropical seas, but most of these species are threatened. In order to understand the patterns and processes that led to their present low diversity and the possible consequences of their particular anatomy, the team has studied the body shapes of angel sharks since their origins using modern methods.

Today’s species are very similar

For this purpose, the skulls of extinct species from the late Jurassic period (about 160 million years ago) and of present-day species were quantitatively analysed using X-ray and CT images and prepared skulls employing geometric-morphometric approaches. In doing so, the evolution of body shapes could be explained comparatively, independent of body size.

The results show that early angel sharks were different in their external shape, whereas modern species show a comparably lower variation in shape. “Many of the living species are difficult to identify on the basis of their skeletal anatomy and shape, which could be problematic for species recognition,” explains Faviel A. López-Romero.

Angel sharks are well adapted, but react slowly to environmental changes

It has been shown that in living species the individual parts of the skull skeleton are more closely integrated than in their extinct relatives. This led to a reduced variability in appearance during the evolution of angel sharks. “The effect of integrating different parts of the skull into individual, highly interdependent modules can lead to a limited ability to evolve in different forms, but at the same time increases the ability to successfully adapt to specific environmental conditions,” explains Jürgen Kriwet.

In the case of the angel sharks, increasing geographical isolation resulted in the development of different species with very similar adaptations. “But modular integration also means that such animals are no longer able to react quickly to environmental changes, which increases their risk of extinction,” concludes Jürgen Kriwet.