Eocene little primates discovered in China


This 2015 video is called Evolution of primates.

From Northern Illinois University in the USA:

Finger and toe fossils belonged to tiny primates 45 million years ago

November 9, 2017

Summary: A new study identifies nearly 500 minuscule finger and toe bones as belonging to 45-million-year-old tiny primates. Many of the fossils are so small they rival the diminutive size of a mustard seed. Representing nine different taxonomic families of primates and as many as 25 species, the specimens from China include numerous fossils attributed to Eosimias, the very first anthropoid known to date, and three fossils attributed to a new and more advanced anthropoid.

At Northern Illinois University, Dan Gebo opens a cabinet and pulls out a drawer full of thin plastic cases filled with clear gelatin capsules. Inside each numbered capsule is a tiny fossil — some are so small they rival the diminutive size of a mustard seed.

It’s hard to imagine that anyone would be able to recognize these flecks as fossils, much less link them to an ancient world that was very different from our own, yet has quite a bit to do with us — or the evolution of us.

The nearly 500 finger and toe bones belonged to tiny early primates — some half the size of a mouse. During the mid-Eocene period, about 45 million years ago, they lived in tree canopies and fed on fruit and insects in a tropical rainforest in what is now China.

The fossilized phalanges are described in detail in a new study by Gebo and colleagues, published online this fall ahead of print in the Journal of Human Evolution.

Representing nine different taxonomic families of primates and as many as 25 species, the specimens include numerous fossils attributed to Eosimias, the very first anthropoid known to date, and three fossils attributed to a new and much more advanced anthropoid. The anthropoid lineage would later include monkeys, apes and humans.

“The fossils are extraordinarily small, but in terms of quantity this is the largest single assemblage of fossil primate finger and toe specimens ever recorded,” said Gebo, an NIU professor of anthropology and biology who specializes in the study of primate anatomy.

All of the finger and toe fossils imply tree-dwelling primates with grasping digits in both hands and feet. Many of the smaller fossils are between 1 and 2 millimeters in length, and the animals would have ranged in full body size from 10 to 1,000 grams (0.35 to 35.3 ounces).

“The new study provides further evidence that early anthropoids were minuscule creatures, the size of a mouse or smaller,” Gebo said. “It also adds to the evidence pointing toward Asia as the initial continent for primate evolution. While apes and fossil humans do come from Africa, their ancestors came from Asia.”

The newly described fossils were originally recovered from a commercial quarry near the village of Shanghuang in the southern Jiangsu Province of China, about 100 miles west of Shanghai. In recent decades, Shanghuang has become well-known among paleontologists.

“Shanghuang is truly an amazingly diverse fossil primate locality, unequaled across the Eocene,” Gebo said. “Because no existing primate communities show this type of body-size distribution, the Shanghuang primate fauna emphasizes that past ecosystems were often radically different from those we are familiar with today.”

Co-author Christopher Beard, a paleontologist at the University of Kansas in Lawrence who has been working on Shanghuang fossils for 25 years, said the limestone in the quarry is of Triassic age — from the very beginning of the Age of Dinosaurs some 220 million years ago. Owing to a subsequent phase of erosion, the limestone developed large fissures containing fossil-rich sediments dating to the middle Eocene, after dinosaurs went extinct.

In the early 1990s, more than 10 tons of fossil-bearing matrix were collected from the fissures and shipped to the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing and the Carnegie Museum of Natural History in Pittsburgh. There, the matrix was washed and screened, yielding fossil bones and teeth from ancient mammals, many of which remain to be identified.

“Because of commercial exploitation of the quarry site, the fossil-bearing fissure-fillings at Shanghuang are now exhausted,” Beard said. “So, the fossils that we currently have are all that will ever be found from this site.”

Gebo was initially recruited during the late 1990s to spearhead research on primate limb and ankle bones from Shanghuang. That led to two publications in 2000, when he and colleagues first announced the discovery of 45 million-year-old, thumb-length primates, the smallest ever recovered, from this same site. The work identifying body parts also helped cement the status of Eosimias, first identified by Beard on the basis of jaw fragments discovered at the site, as an extremely primitive anthropoid lying at the very beginning of our lineage’s evolutionary past.

In more recent years, Gebo found additional specimens, sifting through miscellaneous elements from Shanghuang both at the Carnegie Museum and the University of Kansas. He brought the delicate and minuscule finger and toe fossils to NIU for study using traditional and electron-scanning microscopes.

The fossils that endured the millennia may be small but still have a story to tell. “We can actually identify different types of primates from the shapes of their fingers and toes,” Gebo said.

Primates are mammals, characterized by having bigger brains, grasping hands and feet, nails instead of claws and eyes located in the front of the skull. Living prosimians, or living lower primates, include lemurs and tarsiers, and have broader fingertips. In contrast, most living anthropoids, also known as higher primates, have narrow fingertips.

Fossils from the unnamed advanced anthropoid are narrow, Gebo said.

“These are the earliest known examples of those narrow fingers and toes that are key to anthropoid evolution,” he added. “We can see evolution occurring at this site, from the broader finger or toe tips to more narrow.”

Unlike other prehistoric forests across the globe that have a mixture of large and small primates, Shanghuang’s fossil record is unique in being nearly absent of larger creatures.

The unusual size distribution is likely the result of a sampling bias, Gebo said. Researchers might be missing the larger primate fauna because of processes affecting fossil preservation, and for similar reasons scientists at other Eocene localities could be missing the small-sized fauna.

“Many of the fossil specimens from Shanghuang show evidence of partial digestion by predatory birds, which may have specialized on preying upon the small primates and other mammals that are so common at Shanghuang, thus explaining the apparent bias toward small fossil species there,” Beard added.

Some of the primate fossils found in Shanghuang are found in other countries. Eosimias fossils have been recovered in Myanmar, for example. But Shanghuang stands out because of the presence of more advanced anthropoids and the sheer diversity of primates.

“You don’t find all of these fossil primates in one place except at Shanghuang,” Gebo said.

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Prehistoric bat ate mammals


This video says about itself:

11 July 2014

Secrets and Mysteries of Bats – Nature Documentary

This 48-minute documentary explores the world of bats and the scientists who study them — including the late Donald Griffin, a Harvard zoologist who was the first to describe their echolocation ability in the 1940s. Using 3-D graphics to recreate the bats’ acoustic vision and shooting with infra-red and high-speed cameras, this film offers an exhilarating “bat‘s eye” journey into the night.

By Carlos Albuquerque, 27 October 2017:

Prehistoric bat munched on mammals

Known from fossils found in Eocene-aged rocks in Europe and Africa, this ancient bat didn’t eat fruit or insects, like most living bats. Instead its teeth show it focused on larger targets.

As a group, bats are unfairly maligned as flying monsters. Unless you’re a bug or a banana, most bats are fairly harmless. Nonetheless, as nocturnal animals with features considered aberrant by human beings, bats have captured the imagination of cultures around the world as flying demons. And one particular extinct genus doesn’t ease the mind when it comes to these stereotypes.

Few prehistoric animals can be as lucky as the bat Necromantis. It has just such a wonderfully over-the-top name, literally “death eater.” Nothing could be more perfect than a monstrous name for what was, in life, a cute flying mammal.

Necromantis fossils were first found in Eocene age rocks in France, but more recently they have also turned up in Tunisia, showing a wide range across the eastern hemisphere. A variety of other bat taxa can be found in the early Cenozoic of Africa and Europe, but few are present in both continents, even during the various periods of faunal exchange between both continents.

Though its exact wingspan isn’t clear, Necromantis was one of the largest bats living in its environment. What really set it apart from its contemporaries were its jaws and teeth.

The skull of Necromantis bears a tall ridge called a sagittal crest anchoring the muscles that close the jaws and massive canines and molars similar to the carnassial teeth of carnivorous mammals. These dental features are unique among bats, as even modern carnivorous bats lack carnassials.

Necromantis was decidedly specialized for carnivory, with its carnassial-like teeth allowing for more efficient cutting and butchering of flesh than any other bat. The stout lower jaw also suggests that the bite was focused on crushing action. These features show it was the bat most dedicated to carnivory so far known, it may have scavenged, and could probably hunt larger prey like mice, birds, or even other bats.

The structure of the inner ear shows that the head was held with its snout angled downward, a feature seen in modern leaf-nosed bats. They echolocate by emitting sounds from their nostrils, and Necromantis may have too. The fleshy, leaf-shaped nasal extensions are thought to help with echolocation, and Necromantis may have been similarly equipped.

Like the carnivorous marsupial Anatoliadelphys, Necromantis was probably some odd evolutionary experiment in mammalian carnivory. Their region of the globe was also occupied by many odd animal groups such as hyaenodonts and the enigmatic ptolemaiidans.

References:

Anthony Ravel; Mohammed Adaci; Mustapha Bensalah; Anne-Lise Charruault; El Mabrouk Essid; Hayet Khayati Ammar; Wissem Marzougui; Mohammed Mahboubi; Fateh Mebrouk; Gilles Merzeraud; Monique Vianey-Liaud; Rodolphe Tabuce; Laurent Marivaux (2016). “Origine et radiation initiale des chauves-souris modernes : nouvelles découvertes dans l’Éocène d’Afrique du Nord”. Geodiversitas. 38 (3): 355–434. doi:10.5252/g2016n3a3.

Gunnell GF & Simmons NB, Evolutionary History of Bats: Fossils, Molecules and Morphology, Cambridge University Press, 2012. ISBN 978-0-521-76824-5

Fossil sea turtle baby, new research


Tasbacka danica, photo by Johan Lindgren

From North Carolina State University in the USA:

Keratin, proteins from 54-million-year-old sea turtle show survival trait evolution

October 17, 2017

Researchers from North Carolina State University, Lund University in Sweden and the University of Hyogo in Japan have retrieved original pigment, beta-keratin and muscle proteins from a 54 million-year-old sea turtle hatchling. The work adds to the growing body of evidence supporting persistence of original molecules over millions of years and also provides direct evidence that a pigment-based survival trait common to modern sea turtles evolved at least 54 million years ago.

Tasbacka danica is a species of sea turtle that lived during the Eocene period, between 56 and 34 million years ago. In 2008 an extremely well-preserved T. danica hatchling was recovered from the Für formation in Jutland, Denmark. The specimen was less than 3 inches (74 millimeters) long. In 2013 paleontologist Johan Lindgren of Lund University uncovered soft tissue residues from an area located near the sea turtle’s left “shoulder.” He collected five small samples for biomolecular analysis.

The shells of modern sea turtle hatchlings are dark colored — this pigmentation gives them protection from aerial predators (such as seagulls) as they float on the ocean surface to breathe. Since turtles are reptiles, and therefore cold-blooded, the dark coloration also allows them to absorb heat from sunlight and regulate their body temperature. This elevated body temperature also allows more rapid growth, reducing the time they are vulnerable at the ocean surface.

The T. danica hatchling specimen appeared to share this coloration with its living counterparts. The researchers observed round organelles in the fossil that could be melanosomes, pigment-containing structures in the skin (or epidermis) that give turtle shells their dark color.

To determine the structural and chemical composition of the soft tissues Lindgren collected and see if the fossil sea turtle did have a dark colored shell, the researchers subjected the sample to a selection of high-resolution analytical techniques, including field emission gun scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM), in situ immunohistochemistry, time-of-flight secondary ion mass spectrometry (ToF-SIMS), and infrared (IR) microspectroscopy.

Lindgren performed ToF-SIMS on the samples to confirm the presence of heme, eumelanin and proteinaceous molecules — the components of blood, pigment and protein.

Co-author Mary Schweitzer, professor of biological sciences at NC State with a joint appointment at the North Carolina Museum of Natural Sciences, performed histochemical analyses of the sample, finding that it tested positive against antibodies for both alpha and beta-keratin, hemoglobin and tropomyosin, a muscle protein. TEM, performed by University of Hyogo evolutionary biologist Takeo Kuriyama, and Schweitzer’s immunogold testing further confirmed the findings.

In the end, the evidence pointed to these molecules as being original to the specimen, confirming that these ancient turtles shared a pigmentation-based survival trait with their modern-day brethren.

“The presence of eukaryotic melanin within a melanosome embedded in a keratin matrix rules out contamination by microbes, because microbes cannot make eukaryotic melanin or keratin,” Schweitzer says. “So we know that these hatchlings had the dark coloration common to modern sea turtles.

“The data not only support the preservation of multiple proteins, but also suggest that coloration was used for physiology as far back as the Eocene, in the same manner as it is today.”

The scientific report on this is here.

What a prehistoric salamander ate


Phosphotriton sigei

This picture shows a three-dimensional reconstruction of the skeleton of Phosphotriton sigei gen. et sp. nov. (B), scaled to the same length as other Eurasian urodeles: a European plethodontid, Hydromantes italicus Dunn, 1923 (A), and two salamandrids, Hypselotriton orientalis (David, 1873) (C) and Salamandra salamandra (Linnaeus, 1758) (D).

From ScienceDaily:

Ancient petrified salamander reveals its last meal

Researchers identify frog bones within the stomach of a 35 million year old ‘mummified’ salamander fossil using advanced x-ray imaging techniques. At least six kinds of organs are preserved in almost perfect condition

October 3, 2017

A new study on an exceptionally preserved salamander from the Eocene of France reveals that its soft organs are conserved under its skin and bones. Organs preserved in three dimensions include the lung, nerves, gut, and within it, the last meal of the animal, according to a study published in the peer-reviewed journal PeerJ by a team of palaeontologists from France and Switzerland.

Accessing the complete anatomy of an extinct animal, i.e. both its external and internal aspects, has often been the dream of palaeontologists. Indeed, in 99% of cases, fossils are only represented by hard parts: bones, shells, etc. Fossils preserving soft tissues exist, but they are extremely rare. However, their significance for science is enormous. What did the animal look like? What did they eat? How did they live? Most of these questions can be answered by exceptionally preserved fossils.

The newly studied fossil externally looks like a present-day salamander, but it is made of stone. This fossil “mummy” is the only known specimen of Phosphotriton sigei, a 40-35 million years old salamander and belongs to the same family as the famous living fire salamander (Salamandra salamandra).

It is unfortunately incomplete: only the trunk, hip and part of hind legs and tail are preserved. Until very recently, the only thing palaeontologists could tell about this specimen was visible anatomical details, such as the cloaca, the orifice used for reproduction and by digestive and urinary canals. Indeed, though it was discovered in the 1870s, it was never studied in detail.

Thanks to recent synchrotron technology, its skeleton and various organs could be studied. The specimen was scanned at the ID19 beamline of the European Synchrotron Radiation Facility (ESRF) in Grenoble (France). This modern technology gave access to an incredible level of details that could never have been achieved before without slicing the specimen into a series of thin sections.

The quality of preservation is such that looking at the tomograms (equivalent of radiograms) feels like going through an animal in the flesh. At least six kinds of organs are preserved in almost perfect condition, in addition to the skin and skeleton: muscles, lung, spinal cord, digestive tract, nerves, and glands.

But the most incredible is the preservation of frog bones within the stomach of the salamander. Salamanders almost never eat frogs or other salamanders, though they are known to be quite opportunistic. Was it a last resort meal or a customary choice for this species? This, unfortunately, will probably never be known.

These new results are described by Jérémy Tissier from the Jurassica Museum and the University of Fribourg in Switzerland, and Jean-Claud Rage and Michel Laurin, both from the CNRS/Museum national d’histoire naturelle/UPMC in Paris.

Author Michel Laurin notes, “This fossil, along with a few others from the same lost site, is the most incredibly well-preserved that I have seen in my entire career. And now, 140 years after its discovery, and 35 million years after the animal died, we can finally study it, thanks to modern technology. The mummy returns!”

Tasmanian devil-like fossil marsupial discovery in Turkey


An artist’s reconstruction of Anatoliadelphys maasae. Image credit: Peter Schouten

From the University of Salford in England:

‘Euro Devil’: Fossil of carnivorous marsupial relative discovered in E Europe

August 17, 2017

Scientists have discovered fossil remains of a new carnivorous mammal in Turkey, one of the biggest marsupial relatives ever discovered in the northern hemisphere.

The findings, by Dr Robin Beck from the University of Salford in the UK and Dr Murat Maga, of the University of Washington who discovered the fossil, are published today in the journal PLoS ONE.

The new fossil is a 43 million year old cat-sized mammal that had powerful teeth and jaws for crushing hard food, like the modern Tasmanian Devil. It is related to the pouched mammals, or marsupials, of Australia and South America, and it shows that marsupial relatives, or metatherians, were far more diverse in the northern hemisphere than previously believed.

Dr Maga found the fossil at a site near the town of Kazan, northwest of the Turkish capital, Ankara. It has been named Anatoliadelphys maasae, after the ancient name for Turkey, and Dr Mary Maas, a Turkish-American palaeontologist. The fossil is remarkably well preserved, and includes parts of the skull and most of the skeleton.

It shows that Anatoliadelphys weighed 3-4 kilograms, about the size of a domestic cat, and that it was capable of climbing. It had powerful teeth and jaws, for eating animals and possibly crushing bones. Features of the teeth and bones of Anatoliadelphys show that is closely related to marsupials, but it is not known whether it had a pouch or not.

Dr Beck, who is a world expert in the evolution of marsupials and their fossil relatives, said: “This was definitely an odd little beast — imagine something a bit like a mini-Tasmanian devil that could climb trees.

“It could probably have eaten pretty much anything it could catch — beetles, snails, frogs, lizards, small mammals, bones, and probably some plant material as well. This find changes what we thought we knew about the evolution of marsupial relatives in the northern hemisphere — they were clearly a far more diverse bunch than we ever suspected.”

Most fossil metatherians from the northern hemisphere were insect-eating creatures no bigger than mice or rats, whereas Anatoliadelphys was ten times larger and could have eaten vertebrate prey.

“It might seem odd to find a fossil of a marsupial relative in Turkey, but the ancestors of marsupials actually originated in the northern hemisphere, and they survived there until about 12 million years ago,” said Dr Beck.

The region of Turkey where Anatoliadelphys was found was probably an island 43 million years ago, which may have enabled Anatoliadelphys to survive without competition from carnivorous placental mammals, such as fossil relatives of cats, dogs and weasels.

Today, many marsupials in Australia have been driven to extinction due to the introduction of the dingo, cats and foxes, suggesting that marsupials may be competitively inferior to placentals.

See also here.

A large Tasmanian devil relative has been discovered from a new fossil locality in the outback of northwestern Queensland. The Riversleigh fossil site in northwestern Queensland, Australia, is home to a rich fauna of Oligocene to Miocene aged marsupials. A new fossil site called Wholly Dooley Hill has been discovered near Riversleigh. Wholly Dooley Hill preserves sediments that were deposited in the floor of a limestone cave, a cave that has since eroded and only preserves its floor: here.

Fossil insect discovery in Indian amber


This video says about itself:

Frauke and Nina collecting Cambay Amber in Vastan, India in 2012. Video by Keith Luzzi.

From ScienceDaily:

Time flies: Insect fossils in amber shed light on India’s geological history

A new species of fungus gnat in Indian amber closely resembles its fossil relatives from Europe, disproving the concept of a strongly isolated Indian subcontinent

May 17, 2017

Summary: Researchers have identified three new species of insects encased in Cambay amber dating from over 54 million years ago. Researchers describe the new species of fungus gnats, which provide further clues to understanding India’s past diversity and geological history.

A new species of fungus gnat in Indian amber closely resembles its fossil relatives from Europe, disproving the concept of a strongly isolated Indian subcontinent.

Researchers have identified three new species of insects encased in Cambay amber dating from over 54 million years ago. In a new study published by PeerJ, researchers describe the new species of fungus gnats, which provide further clues to understanding India’s past diversity and geological history.

The most interesting finding from the discovery of these new gnat species is related to India´s plate tectonic history: Palaeognoriste orientale in Cambay amber belongs to a group that has previously been reported from slightly younger Baltic amber only. The species in Indian amber closely resembles its fossil relatives from Europe and therefore adds further evidence to regular faunal exchange between India and Europe while disproving the concept of a strongly isolated Indian subcontinent.

India, which was one part of the ancient supercontinent, Gondwana, started separating and heading north about 130 million years ago, finally collided with Asia some 59 million years ago, resulting in the Himalayan mountains. The time of formation of this amber (or at least its burial) is most likely around the time of collision of the Indian subcontinent with Asia.

The fossils of long beaked fungus gnats (Lygistorrhinidae) found in the Cambay amber are an exciting discovery. The name of this group refers to one of their most conspicuous characters: an elongated proboscis, which is presumably for feeding from flowers. This small family of tropical flies is known by only seven fossil and eight living genera. Given the rareness of this group Indian amber has revealed a surprising diversity with three species in three different fossil and modern genera. This even exceeds the number of known species in the well-studied Baltic amber, from which only two species are reported.

Cambay amber from India has only been studied for a few years, but is already providing an important role in uncovering secrets regarding the origins of India´s fauna. For many years, the well-established theory stated that India formed an isolated continent during its drift, allowing a highly endemic biota to develop. However, flies and other insects entrapped in Indian amber continue to reveal faunal connections to different epochs and regions of the world.

Though the exact mechanisms of faunal exchange remain unclear so far, dispersal might have been facilitated by an island chain system between India and Europe, as has already been suggested for biting midges.

Baleen whales’ ancestry, new study


This video from Australia says about itself:

How suction feeding preceded filtering in baleen whale evolution

29 November 2016

A remarkable 25-million-year-old whale fossil called ‘Alfred’ has provided long-sought evidence of how whales evolved from having teeth to hair-like baleen – triggering their rise as the largest creatures on Earth.

From ScienceDaily:

Baleen whales’ ancestors were toothy suction feeders

May 11, 2017

Summary: Modern whales’ ancestors probably hunted and chased down prey, but somehow, those fish-eating hunters evolved into filter-feeding leviathans. An analysis of a 36.4-million-year-old whale fossil suggests that before baleen whales lost their teeth, they were suction feeders that most likely dove down and sucked prey into their mouths. The study also shows that whales most likely lost the hind limbs that stuck out from their bodies more recently than previously estimated.

Modern whales’ ancestors probably hunted and chased down prey, but somehow, those fish-eating hunters evolved into filter-feeding leviathans. An analysis of a 36.4-million-year-old whale fossil suggests that before baleen whales lost their teeth, they were suction feeders that most likely dove down and sucked prey into their large mouths. The study published on May 11 in Current Biology also shows that whales most likely lost the hind limbs that stuck out from their bodies more recently than previously estimated.

The specimen, which researchers unearthed in the Pisco Basin in southern Peru, is the oldest known member of the mysticete group, which includes the blue whale, the humpback whale, and the right whale. At 3.75-4 meters long, this late Eocene animal was smaller than any of its living relatives, but the most important difference was in the skull. Modern mysticetes have keratin fibers — called baleen — in place of teeth that allow them to trap and feed on tiny marine animals such as shrimp. However, the newly described whale has teeth, so the paleontologists dubbed it Mystacodon, meaning “toothed mysticete.”

“This find by our Peruvian colleague Mario Urbina fills a major gap in the history of the group, and it provides clues about the ecology of early mysticetes,” says paleontologist and study co-author Olivier Lambert of the Royal Belgian Institute of Natural Sciences. “For example, this early mysticete retains teeth, and from what we observed of its skull, we think that it displays an early specialization for suction feeding and maybe for bottom feeding.”

Mystacodon’s teeth exhibit a pattern of wear that differs from more archaic whales, the basilosaurids. Many basilosaurids were probably active hunters, similar to modern orcas, with mouths that were suited for biting and attacking, but Mystacodon has a mouth more suited for sucking in smaller animals, leading the researchers to conclude that Mystacodon most likely represents an intermediate step between raptorial and filter feeding and between the ancient basilosaurids and modern mysticetes.

“For a long time, Creationists took the evolution of whales as a favorite target to say that, ‘Well, you say that whales come from a terrestrial ancestor, but you can’t prove it. You can’t show the intermediary steps in this evolution,'” says Lambert. “And that was true, maybe thirty years ago. But now, with more teams working on the subject, we have a far more convincing scenario.”

Mystacodon bolsters that argument by displaying features of both basilosaurids and mysticetes. “It perfectly matches what we would have expected as an intermediary step between ancestral basilosaurids and more derived mysticetes,”says Lambert. “This nicely demonstrates the predictive power of the theory of evolution.”

Lambert and his colleagues think that Mystacodon may have started suction feeding in response to ecological changes. In illustrated reconstructions, Mystacodon is depicted diving down to the sea floor in a shallow cove, but based on this initial analysis, the researchers aren’t sure to which extent Mystacodon was adapted to bottom feeding. “We will look inside the bone to see if we can find some changes that may be correlated with this specialized behavior,” says Lambert. “Among marine mammals, when a slow-swimming animal is living close to the sea floor, generally the bone is much more compact, and this is something we want to test with these early mysticetes.”

The fossil’s pelvis offered another surprise: Mystacodon had fully articulated, tiny vestigial hind limbs that would have stuck out away from the whale’s body. Previously, paleontologists had thought that whales lost the hip articulation during the basilosaurid phase of their evolution, before baleen whales and modern toothed whales diverged. Though Mystacodon’s hind limbs were already tiny and well down the path toward being vestigial and useless, their articulation with the pelvis suggests that mysticetes and modern toothed whales may have lost this feature independently.

“For a long time, our comprehension of whale evolutionary history was hampered by the fact that most paleontologists were searching for bones relatively close to home, in Europe and North America,” Lambert says. “However, key steps in whales’ evolution happened in areas now occupied by India, Pakistan, Peru, and even Antarctica.” Lambert and his colleagues plan to return to the excavation site in Peru to see if they can find more whale fossils from different epochs.

See also here.

In a recent paper published in PLOS One, Saint Louis University professor of physics Jean Potvin, Ph.D., and biologist Alexander Werth, Ph.D. at Hampden-Sydney College, detail for the first time how baleen whales use crossflow filtration to separate prey from water without ever coming into contact with the baleen: here.