Pterosaurs video


This 12 October 2018 video says about itself:

Pterosaurs 101 | National Geographic

Pterosaurs were the first vertebrates to take to the skies. Learn about the anatomical features that made their flight possible, how large some of these creatures grew, and which species was named after a vampire legend.

Advertisements

Smallest Tylosaurus mosasaur fossil ever discovered


This 2015 video from Canada is called Blair Malazdrewich meets up with an 80 million year old Manitoba celebrity, Bruce the Mosasaur.

From ScienceDaily:

Smallest ever Tylosaurus fossil sheds light on species

October 12, 2018

The smallest Tylosaurus mosasaur fossil ever found has been revealed in a new study in the Journal of Vertebrate Paleontology and surprisingly it lacks a trademark feature of the species.

The fossil, likely to be that of a newborn, does not have the recognizable long snout typically seen in the species. The lack of this snout initially perplexed researchers, who struggled to identify which group of mosasaurs it belonged to.

After examining and comparing the fossil to young specimens of closely-related species, such as T. nepaeolicus and T. proriger which already had identifiable noses, researchers finally deemed it to be a young Tylosaurus.

Lead author Professor Takuya Konishi, of the Department of Biological Sciences at the University of Cincinnati said, “Having looked at the specimen in 2004 for the first time myself, it too took me nearly 10 years to think out of that box and realize what it really was — a baby Tylosaurus yet to develop such a snout.

For those 10 years or so, I had believed too that this was a neonate of Platecarpus, a medium-sized (5-6m) and short-snouted mosasaur, not Tylosaurus, a giant (up to 13m) mosasaur with a significantly protruding snout.”

The lack of snout in the baby specimen found suggests to researchers that the development of this feature happens extremely quickly, between birth and juvenile stage — something that previous studies on the species had failed to notice.

Konishi further commented, “Yet again, we were challenged to fill our knowledge gap by testing our preconceived notion, which in this case was that Tylosaurus must have a pointy snout, a so-called ‘common knowledge.’

As individual development and evolutionary history are generally linked, the new revelation hints at the possibility that Tylosaurus adults from much older rock units may have been similarly short-snouted, something we can test with future discoveries.”

The fragments found include a partial snout with teeth and tooth bases, partial braincase, and a section of upper jaw with tooth bases. From this, they can estimate the entire baby skull to have been around 30cm (1ft) in total.

Tylosaurus belong to one of the largest-known groups of mosasaurs, up to 13m long, the front 1.8 m of that body being its head. The baby, therefore, was about 1/6 the size of such an adult.

Michael J. Everhart, a Kansas native and a special curator of paleontology at the Sternberg Museum of Natural History, Hays, Kansas, found the tiny specimens in 1991 in the lower Santonian portion of the Niobrara Chalk, in Kansas, which are now housed at the museum. The paper was co-authored by Paulina Jiménez-Huidobro and Michael W. Caldwell of the University of Alberta, Canada.

Did prehistoric sea creatures called mosasaurs subdue prey by ramming them with their bony snouts like killer whales do today? Here.

London Natural History museum abused by Saudi regime


The entrance hall of the Natural History Museum in London, with a whale skeleton

From daily The Morning Star in Britain, Friday, October 12, 2018:

Natural History Museum slammed for hosting event by Saudi embassy

BOSSES at the Natural History Museum in London were slammed today for hosting an event by the Saudi Arabian embassy.

The event last night was condemned by the Campaign Against the Arms Trade (CAAT), which said that Saudi Arabia is embroiled in a row over the alleged murder of a Saudi journalist in Turkey, and is involved in a war on the Yemen which has brought death and famine to hundreds of thousands of civilians.

Andrew Smith of CAAT said: “The Saudi authorities have a contempt for human rights, and events like this will undoubtedly be regarded as an endorsement. It’s time for the museum to take a stand.”

A museum spokesman said the event was booked by the Saudi embassy over two months ago as a venue for an external event to celebrate Saudi National Day.

“No museum staff are attending as guests or speaking at the event”, the spokesman said.

One would expect at least one museum staff member to be present to open and close the door, and maybe at least another one to prevent drunk or drugged Saudi fat cats from damaging prehistoric animal fossils or other exhibits.

Lizards dreaming like humans?


This video says about itself:

Lizards have REM sleep too

28 April 2016

REM-like sleep may have originated much earlier than thought. Read more here. Read the research here.

From the CNRS in France:

Do lizards dream like us?

October 11, 2018

Claude Bernard Lyon 1 University / Université Jean Monnet), together with a colleague from the MECADEV research laboratory (CNRS / Muséum National d’Histoire Naturelle) (1) have confirmed that lizards exhibit two sleep states, just like humans, other mammals, and birds. They corroborated the conclusions of a 2016 study on the bearded dragon (Pogona vitticeps) and conducted the same sleep investigation on another lizard, the Argentine tegu (Salvator merianae). Their findings, published in PLOS Biology (October 11, 2018), nevertheless point out differences between species, which raises new questions about the origin of sleep states.

During sleep, the body carries out many vital activities: consolidation of knowledge acquired during the day, elimination of metabolic waste from the brain, hormone production, temperature regulation, and replenishment of energy stores. It would appear that this physiological phenomenon is shared by all members of the animal kingdom and has been preserved throughout evolution. But scientists long thought that only land mammals and birds experienced two separate sleep states: slow-wave sleep and REM, or paradoxical, sleep. The latter, associated with dreaming, is a complex phase during which the body exhibits behaviors in limbo between those of sleeping and waking hours.

A study whose findings were published by Science in 2016 focused on the bearded dragon (Pogona vitticeps) and demonstrated that this lizard also entered two distinct sleep states. It further hypothesized that such sleep states originated in a common ancestor of mammals and reptiles, 350 million years ago.

The team of researchers from the CNRS and Claude Bernard Lyon 1 University began by replicating the 2016 bearded dragon experiment. They then conducted a new investigation using another species of lizard, the Argentine tegu (Salvator merianae). Their data confirm both lizards go into two distinct sleep states bearing similarity to slow-wave and REM sleep, respectively.

But their analysis of behavioral, physiological, and cerebral parameters dug deeper and revealed differences not only between the sleep of the lizards and the sleep of both mammals and birds, but also between the two lizard species. Although human REM sleep is characterized by cerebral and ocular activity similar to that observed while awake, the corresponding state in both lizard species is associated with slower eye movements and, in the case of the tegu, cerebral activity very unlike that of waking hours.

These differences observed by the researchers paint a more complex picture of REM sleep in the animal kingdom and open new doors for investigations into the origin of our own sleep patterns and dreams . . . and those of lizards.

(1) Researchers from INSA Lyon also participated.

Wild chimpanzees share food with friends


This 10 October 2018 video from the Ivory Coast says about itself:

Honey sharing in wild chimpanzees of the Taï Forest – Taï Chimpanzee Project

From the Max Planck Institute for Evolutionary Anthropology in Germany:

Wild chimpanzees share food with their friends

October 10, 2018

Summary: Why share food with non-family members when there is no immediate gain? An international team of researchers conducted observations of natural food sharing behavior of the chimpanzees of the Tai National Park, Ivory Coast. They found that chimpanzees who possess large, desirable food items, like meat, honey or large fruit share food with their friends, and that neither high dominance status nor harassment by beggars influenced possessors’ decisions to share.

Sharing meat after hunting and exchanging other valued food items is considered key in the evolution of cooperation in human societies. One prominent idea is that humans share valuable foods to gain future favors, such that those we chose to share with are more likely to cooperate with us in the future. Despite regularly occurring in humans, sharing food outside of kinship or mating relationships is rare in non-human animals. Our two closest living relatives, chimpanzees and bonobos, are two of the rare exceptions, and because of the important role of food sharing in human evolution, examining the sharing patterns of chimpanzees can help to answer questions on how sharing food amongst adults evolved and how it may have shaped human cooperation.

Researchers from the MPI-EVA observed natural food sharing behavior of the chimpanzees of the Tai National Park, Ivory Coast, and found that chimpanzees are very selective in who they share desirable food items, like meat, honey or large fruits, with. They show that chimpanzees were more likely to share food with their friends, and that neither high dominance status nor harassment by beggars influenced their decision. This complements results from another study by the same team published last month that examined meat sharing after group hunting of monkeys. There they found that chimpanzees in possession of meat after successful hunts were likely to reward other hunters by sharing with them. “Collectively our research shows that the chimpanzees decide when to share food based on the likelihood that this favor will be returned in the future,” says Liran Samuni, first author of both studies. “Or, in case of sharing after group hunts, sharing of meat is returning the favor for helping out.”

Previous studies in another subspecies of chimpanzees have suggested that food sharing in chimpanzees mainly occurs because of harassment pressure from beggars. “This was not the case for the Tai chimpanzees”, Catherine Crockford, senior author on the studies, points out, “emphasizing the high variation in cooperation across chimpanzee populations.” Human populations also vary in how cooperative they are and research is ongoing in both humans and non-human animals assessing what might make some populations more cooperative than others. “The need to stay in a cohesive unit, because of high predation pressure, or the capability to exhibit strong cohesion, because of rich food sources, are two possible scenarios to promote the expression of cooperative acts”, suggests Roman Wittig, the second senior author of the studies.

Additionally, the researchers collected urine samples from chimpanzees after hunting and food sharing events and measured the hormone oxytocin. “We know that oxytocin plays a strong role in lactation, which you could look at as an example of food sharing between mother and infant, and is generally involved in social behavior and bonding”, Liran Samuni explains. The researchers found high levels of oxytocin after chimpanzees shared meat and other valued foods, and after chimpanzee participated in hunting with others. “That we found higher oxytocin levels after both hunting and sharing adds to the idea that oxytocin is a key hormone involved in cooperation in general”, Liran Samuni points out.

The researchers conclude that like humans, Tai chimpanzee sharing is selective, and that friends and others that helped acquiring the food benefit more. Emotional connection, as is obvious amongst friends, likely played a crucial role in the evolution of human cooperation.

Oldest flying squirrel fossil discovered


This video says about itself:

9 October 2018

At Can Mata Landfill (els Hostalets de Pierola, Catalonia, Spain), scientists discovered fossil remains of the oldest-known flying squirrel – Miopetaurista neogrivensis. Based on the reconstructions, researchers estimate a weigh between 1.1 and 1.6 kilos, length of almost one meter and a wingspan around 40 centimeters.

From eLife:

Oldest fossil of a flying squirrel sheds new light on its evolutionary tree

October 9, 2018

The oldest flying squirrel fossil ever found has unearthed new insight on the origin and evolution of these airborne animals.

Writing in the open-access journal eLife, researchers from the Institut Català de Paleontologia Miquel Crusafont (ICP) in Barcelona, Spain, described the 11.6-million-year-old fossil, which was discovered in Can Mata landfill, approximately 40 kilometers outside the city.

“Due to the large size of the tail and thigh bones, we initially thought the remains belonged to a primate“, says first author Isaac Casanovas-Vilar, researcher at the ICP. In fact, and much to the disappointment of paleoprimatologists, further excavation revealed that it was a large rodent skeleton with minuscule specialised wrist bones, identifying it as Miopetaurista neogrivensis — an extinct flying squirrel.

Combining molecular and paleontological data to carry out evolutionary analyses of the fossil, Casanovas-Vilar and the team demonstrated that flying squirrels evolved from tree squirrels as far back as 31 to 25 million years ago, and possibly even earlier.

In addition, their results showed that Miopetaurista is closely related to an existing group of giant flying squirrels called Petaurista. Their skeletons are in fact so similar that the large species that currently inhabit the tropical and subtropical forests of Asia could be considered living fossils.

With 52 species scattered across the northern hemisphere, flying squirrels are the most successful group of mammals that adopted the ability to glide. To drift between trees in distances of up to 150 metres, these small animals pack their own ‘parachute’: a membrane draping between their lower limbs and the long cartilage rods that extend from their wrists. Their tiny, specialised wrist bones, which are unique to flying squirrels, help support the cartilaginous extensions.

But the origin of these animals is highly debated. While most genetic studies point towards the group splitting from tree squirrels about 23 million years ago, some 36-million-year-old remains that could belong to flying squirrels have previously been found. “The problem is that these ancient remains are mainly teeth”, Casanovas-Vilar explains. “As the dental features used to distinguish between gliding and non-gliding squirrels may actually be shared by the two groups, it is difficult to attribute the ancient teeth undoubtedly to a flying squirrel. In our study, we estimate that the split took place around 31 and 25 million years ago, earlier than previously thought, suggesting the oldest fossils may not belong to flying squirrels.

“Molecular and paleontological data are often at odds, but this fossil shows that they can be reconciled and combined to retrace history”, he adds. “Discovering even older fossils could help to retrace how flying squirrels diverged from the rest of their evolutionary tree.”

An exceptional site in a rubbish dump

The Can Mata landfill holds a set of more than 200 sites ranging in age between 12.6 and 11.4 Ma (middle to late Miocene). In the last 20 years, excavations carried out by the ICP in Can Mata have led to the identification of more than 80 species of mammals, birds, amphibians and reptiles. A remarkable number of primate remains from the site have revealed three new species of hominoids, nicknamed ‘Pau’ (Pierolapithecus catalaunicus), ‘Laia’ (Pliobates cataloniae) and ‘Lluc’ (Anoiapithecus brevirostris). Various studies of mammal remains recovered from the site, including the current work in eLife, indicate the existence of a dense subtropical forest.

Giant prehistoric amphibians, video


This PBS video from the USA says about itself:

When Giant Amphibians Reigned

9 October 2018

Temnospondyls were a huge group of amphibians that existed for 210 million years. And calling them ‘diverse’ would be putting it mildly. Yet in the end, two major threats would push them to extinction: the always-changing climate and the amniote egg.