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.

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Kenyan fossil ‘bat’ is fossil primate


Propotto leakeyi fossil, photo Duke SMIF

From Duke University in the USA:

Enigmatic African fossils rewrite story of when lemurs got to Madagascar

Specimens suggest Madagascar’s lemurs were not the first mammals on the island

August 21, 2018

Summary: Research reveals that a 20-million-year-old African fossil, long thought to be a bat, actually represents one of the earliest branches of the lemur family tree. The reassessment challenges a long-held view that lemurs descended from ancestors that colonized Madagascar in a single wave roughly 60 million years ago, and were the first mammals to get there. Instead, the researchers say two separate lemur lineages may have arrived independently, and much later than previously thought.

Discovered more than half a century ago in Kenya and sitting in museum storage ever since, the roughly 20-million-year-old fossil Propotto leakeyi was long classified as a fruit bat.

Now, it’s helping researchers rethink the early evolution of lemurs, distant primate cousins of humans that today are only found on the island of Madagascar, some 250 miles off the eastern coast of Africa. The findings could rewrite the story of just when and how they got to the island.

In a study to be published August 21 in the journal Nature Communications, researchers have re-examined Propotto’s fossilized remains and suggest that the strange creature wasn’t a bat, but an ancient relative of the aye-aye, the bucktoothed nocturnal primate that represents one of the earliest branches of the lemur family tree.

The reassessment challenges a long-held view that today’s 100-some lemur species descended from ancestors that made their way to Madagascar in a single wave more than 60 million years ago, becoming some of the first mammals to colonize the island.

Instead, the study lends support to the idea that two lineages of lemurs split in Africa before coming to Madagascar. One lineage eventually led to the aye-aye, and the other to all other lemurs. There are no lemurs left on mainland Africa. These ancestors then colonized Madagascar independently, and millions of years later than once believed.

“One implication is that lemurs have had a much less extensive evolutionary history on Madagascar than was previously thought”, said study co-author Erik Seiffert, professor of anatomy at the University of Southern California.

When Propotto was first described in the 1960s, experts didn’t agree about what they were looking at. They didn’t have a lot to go on: just three lower jaw bones, each barely an inch long, and a handful of teeth less than three millimeters across.

In 1967, paleontologist George Gaylord Simpson inspected the fragments and classified the specimen as a previously unknown member of the loris family, nocturnal primates with enormous eyes. But a colleague named Alan Walker took a look and thought otherwise, eventually convincing Simpson that the bones belonged to a bat.

For nearly half a century the creature’s identity appeared to have been settled, until 2016, when another paleontologist, the late Gregg Gunnell of Duke University, began taking a fresh look at the fossil. To Gunnell’s eye, the creature’s hind teeth were more reminiscent of a primate than a bat. He also noted the stump of a broken front tooth, just visible in cross section, which would have jutted out from its mouth like a dagger — a trait only known in aye-ayes, the only living primates with rodent-like teeth.

“Gregg wrote to us and said, ‘Tell me I’m crazy'”, Seiffert said.

To verify Propotto’s place in the primate family tree, Seiffert and Steven Heritage of Duke’s Division of Fossil Primates analyzed more than 395 anatomical features and 79 genes for 125 mammal species, living and extinct.

With help from Doug Boyer, associate professor of evolutionary anthropology at Duke, the team also compiled microCT scans of the lower molars of 42 living and extinct mammal groups, including bats, treeshrews and primates. They then used a computer program to compare the bumps, pits and ridges on the scans of Propotto’s teeth to those of other animals.

The researchers found that Propotto shared a number of features with a similarly buck-toothed primate that lived 34 million years ago in Egypt called Plesiopithecus, and that both were ancient relatives of the aye-aye.

In the new study, Seiffert, Gunnell and colleagues propose that the ancestors of aye-ayes split from the rest of the lemur family tree roughly 40 million years ago, while still on the African continent, and the resulting two lineages didn’t make their separate ways to Madagascar until later.

The findings suggest they arrived around the same time as other mammals, such as rodents, Malagasy mongooses and hedgehog- and shrew-like animals called tenrecs. Frogs, snakes and lizards may have made the trip around the same time.

Lemurs can’t swim, so some scientists hypothesize that the small-bodied creatures crossed the 250-mile-wide channel that lies between Africa and Madagascar after being swept out to sea in a storm, by holding on to tree limbs or floating mats of vegetation before finally washing ashore.

But if the arrival were more recent, they might have had a shorter distance to travel, thanks to lower sea levels when the Antarctic ice sheet was much larger.

“It’s possible that lemurs weren’t in Madagascar at all until maybe the Miocene,” as recently as 23 million years ago, Boyer said.

Then, one may ask: Why did not other, non-lemur, mammals then cross from Africa to Madagascar as well?

“Some of the lowest sea levels were also during this time,” Heritage said.

Either way, “the fossils tell us something we never could have guessed from the DNA evidence about the history of lemurs on Madagascar”, Boyer said.

Ancient whale discovery in Crimea


This 7 March 2018 video says about itself:

TOP 8 MEGALODON MOST LETHAL ENEMIES

7 March 2018

The Megalodon Shark is historically considered the master of the seas; however, it was not alone in the oceans millions of years ago. There were very dangerous enemies who sought to dethrone him and could even kill him at times.

MEGALODON VS LIVYATAN MELVILLEI (LEVIATHAN)
It definitely was the most suitable creature to give it a good fight and even annihilate the huge megalodon from the seas.

-MEGALODON VS ZYGOPHYSETER VAROLAI
It is another of the extinct odontoceti cetaceans, belonging to the sperm whale family. And his name rightly means “murderous sperm whale.”

-MEGALODON VS RHAMPHOSUCHUS
Called “crocodile snout” or “crocodile with beak”, it is an extinct crocodilian genus, whose appearance resembles the modern Malaysian false gharial.

-MEGALODON VS BRYGMOPHYSETER SHIGENSIS
It is a species of extinct Odontoceti cetacean that lived during the Miocene in Japanese waters. Well, it is believed that it also lived in all the oceans of the time.

-MEGALODON VS ALBICETUS
It is a genus of extinct sperm whale that lived about 15 million years ago in the middle Miocene. In 1909, it was discovered in Santa Barbara, California, where it is presumed to be a native.

-MEGALODON VS CETOTHERIUM
Its name means “whale beast” and it is a disappeared genus of Mysticeti cetacean linked with modern whales.

-MEGALODON VS AULOPHYSETER It is an extinct genus of sperm whale that lived during the Miocene, a time when Megalodon was already imposing in all seas of the planet.

-MEGALODON VS THE WORST ENEMY This enemy meant its definitive extinction …, or at least it is what we believe.

From RT.com:

Rare 10-million-year-old whale dug up in Crimea

20 Aug, 2018 07:36

The skeleton of an ancient whale was unearthed by archeologists in Crimea, Russia as they were examining a future railroad site. The animal lived in a sea which disappeared 10 million years ago.

The spine and ribs of a Cetotherium (Latin for ‘whale beast’), an extinct relative of modern whales, were discovered on the Kerch Peninsula as archeologists were examining land designated for railroad construction, local media reported on Friday.

The prehistoric creature was about five meters (16.5 feet) long. The discovery is not surprising, considering that the site was once deep underwater, at the heart of what was the Sarmatian Sea. “The sea eventually became land”, Sergey Yazikov, a researcher at the Archeology Institute of the Russian Academy of Sciences told local media.

“The geological layers have gone up, and the whale’s skeleton appeared on top, although it used to rest on the seabed.”

Dmitry Startsev from the Crimean University’s zoological museum said the remains are quite unique. “All fragments are part of a single specimen. Such discoveries don’t happen often. The structure of the bone tissue is highly visible.”

What prehistoric elephants ate


This video from the USA says about itself:

8 September 2015

Gomphotherium” is an extinct genus of proboscid that evolved in the Early Miocene of North America and lived about from 13.650—3.6 Ma.

The genus emigrated into Asia, Europe and Africa after a drop in sea level allowed them to cross over. It survived into the Pliocene, and its remains have been found in France, Germany, Austria, Kansas, Tennessee, Pakistan, Kenya and Bosnia and Herzegovina.

G. productum” is known from a 35-year-old male 251 cm tall weighing 4.6 t. Even larger is “G. steinheimense“, known from a complete 37-year-old male found in Mühldorf, Germany, it is 317 cm tall weighing 6.7 t. However, it had four tusks; two on the upper jaw and two on the elongated lower jaw. The lower tusks are parallel and shaped like a shovel and were probably used for digging up food from mud.

Unlike modern elephants, the upper tusks were covered by a layer of enamel. Compared to elephants, the skull was more elongated and low, indicating that the animal had a short trunk, rather like a tapir‘s. These animals probably lived in swamps or near lakes, using their tusks to dig or scrape up aquatic vegetation. In comparison to earlier proboscids, “Gomphotherium” had far fewer molars; the remaining ones had high ridges to expand their grinding surface.

From the University of Bristol in England:

Feeding habits of ancient elephants uncovered from grass fragments stuck in their teeth

May 17, 2018

A new study, led by scientists at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing, China, including University of Bristol PhD student Zhang Hanwen, examined the feeding habits of ancient elephant relatives that inhabited Central Asia some 17 million years ago.

Professor Wang Shiqi from IVPP, the study’s senior author, said: “We found ancient elephant teeth in the Junggar Basin, in China’s far North West and they belong to two species, Gomphotherium connexum, and the larger G. steinheimense.”

Zhang Hanwen, from Bristol’s School of Earth Sciences, added: “Gomphotherium was most obviously different from modern elephants by its very long lower jaw that still had lower tusks.

“It also had a shorter, more elongate, barrel-like body shape compared to modern elephants. In essence, a small elephant with short legs.”

Professor Wang explained: “Our study of their evolution shows that Gomphotherium connexum became extinct, but G. steinheimense was part of the line that eventually gave rise to the modern elephants.”

To understand if feeding preference was playing a role in survival and extinction of these elephants, Dr Wu Yan of IVPP, the study’s lead author, analysed tiny remnants of plant matter found stuck to the fossil teeth, called phytoliths.

About 30 percent of the phytoliths extracted from the teeth of G. connexum are from soft foliage, whereas another 50 percent or so comes from grasses.

Dr Wu said: “Given that foliage naturally produces far less phytoliths than grasses, this indicates that G. connexum was mainly feeding on foliage, maybe a generalist feeder of all kinds of plant matter.

“When I examined the phytoliths extracted from the cheek teeth of G. steinheimense, I saw a very different pattern — grass phytoliths comprise roughly 85 percent of the total, suggesting this species was perhaps primarily a grazer 17 million years ago.”

To confirm these results, the team also examined tiny wear patterns on the fossil tooth surfaces called microwear.

Zhang Hanwen added: “Now things start to get interesting. When our team analysed fossil pollen samples associated with the sediments where the Gomphotherium teeth were found, we realised that woodlands were rapidly transforming into semi-arid savannahs when the two species lived together.

“By adopting a much more grass-based diet, G. steinheimense was apparently responding better to this habitat change than G. connexum.

“Gomphotherium had primitive dentition consisting of low molar crowns, and numerous conical cusps arranged in few transverse enamel ridges on the chewing surface of the teeth.

“This was adapted for feeding on leaves, the primitive diet. But later on, the lineage leading to modern elephants and the extinct mammoths evolved an increased number of enamel ridges, and these eventually became densely packed tooth plates for shearing tough vegetation.

“Our new evidence shows that the diet switch from leaves to grass happened long before the anatomical switch in tooth shape.”

New Miocene fossil insectivore discovery


This 2012 video is called Miocene.

From the Asociación RUVID in Spain:

New 16 million-year-old insectivore species discovered

March 14, 2018

Palaeontologists Vicente D. Crespo, Francisco Javier Ruiz Sánchez and Plini Montoya, from the department of Botanics and Geology of the Universitat de València, and Marc Furió, from the Institut Català de Paleontologia, have discovered a new fossilised species of insectivore belonging to the unusual and extinct Plesiodimylus family. The identification of this group, related to the fauna that lived in Central Europe during the Miocene (16 million years ago), is based on the study of isolated teeth found in l’Alcora (Castellón), in the district of Araya.

This new species of insectivore, found in the palaeontological site Mas d’Antolino B, has been unveiled in the Historical Biology journal and has the scientific denomination Plesiodimylus ilercavonicus, in reference to the Iberian Ilercavones people, who inhabited part of what are the provinces of Castellón and Tarrragona today.

This family is defined by having teeth that protrude from the jaw, with thicker dental enamel than other mammals, as well as the presence of four molars (two in each jawbones, or one in each jawbone and then one more in each maxilla). These characteristics give them an unusual look — with overgrown teeth.

Furthermore, by studying the dentition of this species and specially with the type of wear suffered by the teeth’s enamel, one can surmise they would have fed mainly on gastropods, the most common group of mollusks, according to Crespo, Ruiz Sánchez and Montoya — also researchers for Valencia’s Natural History Museum -, and Marc Furió.

Until now, the finding of material from this animal group in Araya is the only one of its kind in the Iberian Peninsula, joining findings of other species from Central Europe such as some types of hamsters and other rodents, bats and insectivores, which reveal a phase of faunistic exchange between Iberia and Central Europe in the Lower Miocene.

In order to obtain the fossilised remains of these small mammals, a strenuous process to clean and sieve through tones of sediment was undertaken, as well as the examination of the residue obtained through this process. The studying of the specimens was performed with various techniques, including some derived from the use of electronic microscopy devices. The results of the study were unveiled at the 15th Annual Meeting of the European Association of Vertebrate Palaeontologists, held in Munich (Germany) during the summer of 2017.

In the Mas d’Antolino B palaeontological site, available since 2008, fossils of other species of shrews, squirrels, hamsters, dormice, bats or crocodiles have been unearthed, among others. These faunas, in a context of an environment similar to the current day rainforests, date back to the Aragonian age of mammals, also within the Miocene period. In this era there was a rainforest where Araya is currently located, with meadows, which would have been located near a great lake which reached most of today’s l’Alcora, Ribesalbes and Fanzara villages.

Mysterious Miocene fossils from Nebraska, USA


This video from the USA says about itself:

29 January 2018

In the late 1800s, paleontologists in Nebraska found huge coils of hardened sand stuck deep in the earth. Local ranchers called them Devil’s Corkscrews and scientists called them Daemonelix. It was clear these corkscrews were created by some form of life, but what?

Marsupial fossil discovery in Australia


This 2016 video is called Extinct and Extant Australian Species.

From Palaeontologia Electronica:

Miminipossum notioplanetes, a Miocene forest-dwelling phalangeridan (Marsupialia; Diprotodontia) from northern and central Australia

ABSTRACT

Miminipossum notioplanetes represents a new Early/Middle Miocene family (Miminipossumidae) of phalangeridan possums recovered from the Two Trees Local Fauna from the Riversleigh World Heritage area in northwestern Queensland and the Kutjamarpu Local Fauna of the Tirari Desert in northern South Australia. Because of widespread convergence in key features of P3 and M1 among phalangeridan families, the interfamilial relationships of Miminipossumidae are uncertain. The age of the Kutjamarpu Local Fauna has been in doubt with estimates ranging from Late Oligocene to Middle Miocene. The new taxon raises to 15 the number of taxa in the Kutjamarpu Local Fauna that are shared with both Riversleigh’s Faunal Zone B (Early Miocene) and Riversleigh’s Faunal Zone C (Middle Miocene) assemblages.

Although there is relatively little biocorrelative support for the estimate of a Late Oligocene age, doubt remains about whether the age is more likely to be Early or Middle Miocene. In terms of palaeoenvironmental implications, because both Riversleigh’s Early and Middle Mio-cene assemblages have been concluded to have accumulated in temperate, wet, species-rich lowland forests, the same or similar Early/Middle Miocene palaeoenvironments may well have extended into central Australia at the time when the Kutjamarpu assemblage was accumulating.