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Extinct Animals News
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 (11-07-2016, 04:04 AM)brotherbear Wrote: The Etruscan bear (Ursus etruscus) is the direct ancestor of the brownbear (Ursus arctos). The Etruscan bear ate meat and lived from about 5.3 million years ago to about 10,000 years ago. Fossils have been found in Asia, Europe and Africa. The Etruscan bear was much smaller than today's grizzly. The Brown bears were evolved from the Asian population of the Etruscan bears, while the Cave bears from the European population.  (11-07-2016, 04:04 AM)brotherbear Wrote: The Etruscan bear (Ursus etruscus) is the direct ancestor of the brownbear (Ursus arctos). The Etruscan bear ate meat and lived from about 5.3 million years ago to about 10,000 years ago. Fossils have been found in Asia, Europe and Africa. The Etruscan bear was much smaller than today's grizzly. I was referring to North American bears in my last post, but quite a great website with detailed info on bears, nonetheless.  (11-07-2016, 05:53 AM)Polar Wrote:(11-07-2016, 04:04 AM)brotherbear Wrote: The Etruscan bear (Ursus etruscus) is the direct ancestor of the brownbear (Ursus arctos). The Etruscan bear ate meat and lived from about 5.3 million years ago to about 10,000 years ago. Fossils have been found in Asia, Europe and Africa. The Etruscan bear was much smaller than today's grizzly. I would suppose then, that three million years ago, in North America, the only bears were the black bear and the various short-faced types. https://www.bear.org/website/bear-pages/...ecies.html 
Skeletal Anatomy of the North American Pangolin Patriomanis americana (Mammalia, Pholidota) from the Latest Eocene of Wyoming (USA) Gaudin, Emry & Morris, 2016
 *This image is copyright of its original author Abstract: "Patriomanis americana is the only pangolin (Mammalia, Pholidota), living or extinct, known from the Western Hemisphere. It derives from latest Eocene (Chadronian North American Land Mammal Age) deposits from central Wyoming and western Montana. Since its initial description more than 40 years ago based on a partial skeleton, several nearly complete skeletons have been discovered, together including nearly every bone in the skeleton. This taxon is thus not only the most completely preserved fossil pangolin but is also among the best preserved of any Eocene mammal taxon. In the present study we have prepared a detailed, bone-by-bone description of the osteology of Patriomanis, comparing it with other well-known fossil pangolin skeletons (Eomanis, Euromanis, Cryptomanis, and Necromanis), as well as representatives of the three extant pangolins genera (Manis, Smutsia, Phataginus). We provide a catalog of all known Patriomanis specimens and their provenance and an extensive series of measurement tables incorporating the comparative taxa. We analyze the alpha-level taxonomy of the genus, concluding that all specimens should be kept in a single species, Patriomanis americana, based on currently available fossil material. We summarize the taxonomic and phylogenetic position of Patriomanis and discuss its implications for the biogeographic history of the order Pholidota. We analyze the paleobiology of Patriomanis, concluding that it was likely a myrmecophagous, arboreal animal with a prehensile tail. Last, we discuss its paleoecology, suggesting that its late appearance in the Eocene record, during a time of global cooling, may imply that earlier pangolins are waiting to be discovered in the Eocene record of Asia and North America." Other articles related: Paleo Profile: North America's Pangolin
Aegyptocetus tarfa, n. gen. et sp. (Mammalia, Cetacea), from the middle Eocene of Egypt: clinorhynchy, olfaction, and hearing in a protocetid whale
Aegyptocetus tarfa Bianucci & Gingerlich, 2016  *This image is copyright of its original author Top: the six limestone plates containing the Aegyptocetus tarfa skeleton before preparation. Plates are lettered a-f from top to bottom stratigraphically. Bottom: schematic shows oblique orientation of the skull, as preserved, relative to bedding and relative to plate surfaces. Photographs and illustration by G. Bianucci and P. D. Gingerich. Abstract: "A new protocetid archaeocete, Aegyptocetus tarfa, is represented by a nearly complete cranium and an associated partial skeleton. The specimen was recovered when marbleized limestone was imported commercially to Italy and cut into decorative facing stone. It came from middle Eocene Tethyan marine strata of the Gebel Hof Formation of Wadi Tarfa in the Eastern Desert of Egypt. Exceptional preservation and preparation enables study of some internal features of the skull as well as its external morphology. The skull of Aegyptocetus is unusual in having the rostrum and frontal portions of the cranium deflected more ventrally relative to the braincase than is typical for archaeocetes. This ventral deflection, clinorhynchy, is a rare specialization related to feeding or hearing that is widely distributed across mammals. Aegyptocetus has well-developed ethmoidal turbinal bones, indicating retention of a functional sense of smell. It also has cranial asymmetry, thinning of the lateral walls of the dentaries, enlarged mandibular canals, and thinning of the anterolateral walls of the tympanic bullae, indicating enhanced ability to hear in water. Neural spines are long on thoracic vertebrae T1 through T8, suggesting that Aegyptocetus was able to support its weight on land like other protocetids. This combination of terrestrial and aquatic characteristics is consistent with interpretation of protocetids as semiaquatic. The pattern of tooth marks preserved on the ribs of Aegyptocetus indicates that the individual studied here was attacked by a large shark, but it is not certain whether this was the cause of death." Other articles related: Whale fossils show important characters of the transition to water
A New and Ontogenetically Younger Specimen of Numataphocoena yamashitai from the Upper Part of the Horokaoshirarika Formation (Lower Pliocene), Numata, Hokkaido, Japan Tanaka, 2016
 *This image is copyright of its original author Reconstruction credits: T. Shinmura Abstract: "A new periotic of Numataphocoena yamashitai from the upper part of the Horokaoshirarika Formation (lower Pliocene), Numata, Hokkaido, Japan shows younger ontogenetic features in comparison to the matured holotype (NFL 7). The referred specimen of N. yamashitai is smaller (approximately 90% in size) than the physically and sexually matured holotype periotic. The holotype (NFL 7) and referred specimen (NFL 2617) show several differences owing to ontogenetic changes, such as: the holotype (NFL 7) has a more strongly swollen medial part of the anterior process, blunt anterior keel, rounded anterodorsal angle, deeper and clearer anterior incisure, more rounded pars cochlearis, deeper and narrower hiatus epitympanicus rather than a flat area, longer posterior process with an extra edge posterolaterally. N. yamashitai differs from other fossil phocoenids in having a narrower and sharper anterior part of the internal acoustic meatus and a robust anterior process. Haborophocoena toyoshimai similarly has a relatively narrow internal acoustic meatus and a robust anterior process, compared with other fossil phocoenids. Between N. yamashitai and H. toyoshimai, N. yamashitai has a narrower internal acoustic meatus and a more robust anterior process. These similarities imply a close relationship between Numataphocoena and Haborophocoena. The new specimen provides diagnostic features and insight into ontogenetic variation of N. yamashitai."
The extreme insular adaptation of Garganornis ballmanni Meijer, 2014: a giant Anseriformes of the Neogene of the Mediterranean Basin Pavia, Meijer, Rossi & Gohlich, 2017
 *This image is copyright of its original author Figure 4. Reconstruction of Garganornis ballmanni Meijer, 2014 based on the newly described fossil remains. This reconstruction is based on a generic Western Palaearctic Goose with short and robust tarsometatarsus, short toes and very short wings according to the known elements of Garganornis ballmanni. Illustration made by Stefano Maugeri. Abstract: "New skeletal elements of the recently described endemic giant anseriform Garganornis ballmanni Meijer, 2014 are presented, coming from the type-area of the Gargano and from Scontrone, southern and central Italy, respectively. The new remains represent the first bird remains found at Scontrone so far, and another shared element between these two localities, both part of the Apulia-Abruzzi Palaeobioprovince. The presence of a very reduced carpometacarpus confirms its flightlessness, only previously supposed on the basis of the very large size, while the morphologies of tarsometatarsus and posterior phalanges clearly indicate the adaptation of G. ballmanni to a terrestrial, non-aquatic, lifestyle. Its very large body size is similar to that observed in different, heavily modified, insular waterfowl and has been normally interpreted as the response to the absence of terrestrial predators and a protection from the aerial ones. The presence of a carpal knob in the proximal carpometacarpus also indicates a fighting behaviour for this large terrestrial bird species." Other articles related: Extinct giant goose used its wings to fight rather than fly Meet the Giant Goose that couldn't fly
A symmoriiform chondrichthyan braincase and the origin of chimaeroid fishes Coates, Jess, Finarelli, Criswell & Tietjen, 2017
 *This image is copyright of its original author Dwykaselachus oosthuizeni Oelofsen, 1986. Reconstruction credits: Kristen Tietjen Abstract: "Chimaeroid fishes (Holocephali) are one of the four principal divisions of modern gnathostomes (jawed vertebrates). Despite only 47 described living species, chimaeroids are the focus of resurgent interest as potential archives of genomic data and for the unique perspective they provide on chondrichthyan and gnathostome ancestral conditions. Chimaeroids are also noteworthy for their highly derived body plan. However, like other living groups with distinctive anatomies, fossils have been of limited use in unravelling their evolutionary origin, as the earliest recognized examples already exhibit many of the specializations present in modern forms. Here we report the results of a computed tomography analysis of Dwykaselachus, an enigmatic chondrichthyan braincase from the ~280 million year old Karoo sediments of South Africa. Externally, the braincase is that of a symmoriid shark and is by far the most complete uncrushed example yet discovered. Internally, the morphology exhibits otherwise characteristically chimaeroid specializations, including the otic labyrinth arrangement and the brain space configuration relative to exceptionally large orbits. These results have important implications for our view of modern chondrichthyan origins, add robust structure to the phylogeny of early crown group gnathostomes, reveal preconditions that suggest an initial morpho-functional basis for the derived chimaeroid cranium, and shed new light on the chondrichthyan response to the extinction at the end of the Devonian period." Other articles related: 280 million-year-old fossil reveals origins of chimaeroid fishes Origins of Elusive 'Ghost Shark' Revealed
First complete fossil Scleropages (Osteoglossomorpha)
Scleropages sinensis Zhang & Wilson, 2017  *This image is copyright of its original author  *This image is copyright of its original author Abstract: "A new species of osteoglossid fish, Scleropages sinensis sp. nov., is described from the Early Eocene Xiwanpu Formation in Hunan and the Yangxi Formation in Hubei, China. The new species was attributed to Scleropages, an extant genus of Osteoglossidae, because it very closely resembles the genus in skull bones, caudal skeleton, the shape and position of fins, and reticulate scales. The new fish is very similar to extant Scleropages except: the nasals do not appear to be ornamented; the sensory pore in the antorbital is large; the posterior infraorbitals are not quite covering the dorsal limb of the preopercle; the posteroventral angle of the preopercle is produced to point; the posteroventral margin of the opercle is concave and the ventral end of the bone is produced to a point; the pectoral fin is very long and extends well behind the beginning of the pelvic fin; the vertebral count is about 46?8; the parapophyses are shorter and the upper and lower caudal rays are nearly as long as the inner rays. The new fish is closer to its Asian neighbor, S. formosus, than to its southern relative, S. leichardti. Scleropages formosus inhabits natural lakes, swamps, flooded forests, and slowly moving, deep parts of rivers with overhanging vegetative cover. It is a carnivorous fish and its food consists mainly of insects, fishes, worms, small amphibians, small mammals, and even birds. S. sinensis may live in the same natural environment and have a similar diet except for the largest items. Sexual dimorphism may exist in S. sinensis. The presumed male has a slimmer and shallower body, a relatively larger head, and a deeper mouth cleft. The discovery of Scleropages sinensis sp. nov. dates the divergence of Scleropages and Osteoglossum to no later than the Early Eocene." Full Article
A new otter of giant size, Siamogale melilutra sp. nov. (Lutrinae: Mustelidae: Carnivora), from the latest Miocene Shuitangba site in north-eastern Yunnan, south-western China, and a total-evidence phylogeny of lutrines
Siamogale melilutra Wang et al., 2017  *This image is copyright of its original author Figure 12. Artist's reconstruction of two individuals of Siamogale melilutra sp. nov., one of them feeding on a freshwater clam. The tapir in the background is Tapirus yunnanensis (Ji et al. 2015). Aquatic plants include water chestnut (Typha) and fox nut (Euryale) (Huang et al. 2015), and the low shrub in foreground is Sichuan peppercorn (Zanthoxylum). Art by Mauricio Antón.  *This image is copyright of its original author Figure 2. Cranium of Siamogale melilutra sp. nov., ZT-10-03-064b, holotype from Shuitangba. A, right lateral, and B, dorsal views.  *This image is copyright of its original author Figure 3. Cranium of Siamogale melilutra sp. nov., ZT-10-03-064b, holotype from Shuitangba. A, left lateral, and B, ventral views. Abstract: "Otters (subfamily Lutrinae) are semi-aquatic predators in the family Mustelidae. Modern otters have a worldwide distribution but their fossil record is poor, often consisting of fragmentary jaws and teeth. Multiple lineages have developed bunodont dentitions with enlargements of molars, usually for cracking molluscs or other hard foods. Some lineages have evolved badger-like teeth and, as a result, were often confused with melines (Old World badger clade). Siamogale thailandica Ginsburg, Invagat, & Tassy, 1983 from the middle Miocene basin of Mae Moh in northern Thailand is one such species, whose fragmentary dental remains have thus far impeded our understanding. A new species of fossil otter, Siamogale melilutra sp. nov., represented by a nearly complete cranium, mandible and partial skeletons of at least three individuals, was recovered from the latest Miocene (∼6.2 Ma) lignite beds of the Shuitangba Site in north-eastern Yunnan Province, south-western China. Computed tomography (CT) restoration of the crushed skull reveals a combination of otter-like and badger-like cranial and dental characteristics. The new species belongs to the Lutrinae because of its possession of a large infraorbital canal and ventral expansion of the mastoid process, among other traits. A distally expanded M1, however, gives a badger-like appearance. In overall morphology the Shuitangba otter is closest to Siamogale thailandica. A previously described jaw (‘Lutra’ aonychoides) from the early Pliocene of the Yushe Basin in north China is also here referred to S. melilutra. No previous attempt has been made to provide a global phylogenetic framework for otters. We present the first combined morphological and molecular (nuclear and mitochondrial DNAs) character matrices of five extant (Pteronura, Lontra, Enhydra, Aonyx, Lutra) and eight extinct genera (Tyrrhenolutra, Paralutra, Paludolutra, Enhydritherium, Siamogale, Vishnuonyx, Sivaonyx, Enhydriodon) to better understand the evolution of bunodont otters. Parsimony and Bayesian analyses consistently recover an eastern Asian clade that includes forms from Shuitangba, Yushe and Mae Moh, all of which are referred to Siamogale." Full Article Other articles related: Scientists discover 6-million-year-old giant otter fossil in China's Yunnan Province NEW ANCIENT OTTER SPECIES AMONG LARGEST EVER FOUND
A new osteichthyan from the late Silurian of Yunnan, China
Sparalepis tingi Choo, Zhu, Qu, Yu, Jia & Zhao, 2017  *This image is copyright of its original author Fig 9. Life restoration of Sparalepis tingi (foreground) and other fauna from the Kuanti Formation. Also in the scene are numerous conodont animals, a pair of the maxillate placoderm Entelognathus (middle distance) and two examples of the osteichthyan Megamastax (background), the largest known Silurian vertebrate. Illustration by Brian Choo, released under Creative Commons Attribution Licence CC BY 4.0, 2016. Abstract: "Our understanding of early gnathostome evolution has been hampered by a generally scant fossil record beyond the Devonian. Recent discoveries from the late Silurian Xiaoxiang Fauna of Yunnan, China, have yielded significant new information, including the earliest articulated osteichthyan fossils from the Ludlow-aged Kuanti Formation. Here we describe the partial postcranium of a new primitive bony fish from the Kuanti Formation that represents the second known taxon of pre-Devonian osteichthyan revealing articulated remains. The new form, Sparalepis tingi gen. et sp. nov., displays similarities with Guiyu and Psarolepis, including a spine-bearing pectoral girdle and a placoderm-like dermal pelvic girdle, a structure only recently identified in early osteichthyans. The squamation with particularly thick rhombic scales shares an overall morphological similarity to that of Psarolepis. However, the anterior flank scales of Sparalepis possess an unusual interlocking system of ventral bulges embraced by dorsal concavities on the outer surfaces. A phylogenetic analysis resolves Sparalepis within a previously recovered cluster of stem-sarcopterygians including Guiyu, Psarolepis and Achoania. The high diversity of osteichthyans from the Ludlow of Yunnan strongly contrasts with other Silurian vertebrate assemblages, suggesting that the South China block may have been an early center of diversification for early gnathostomes, well before the advent of the Devonian “Age of Fishes”." Other articles related: The (Now Older) Age of Fishes: New bony fish from the Silurian of China Ancient southern China fish may have evolved prior to the 'Age of Fish'
A new Early Cretaceous tritylodontid (Synapsida, Cynodontia, Mammaliamorpha) from the Kuwajima Formation (Tetori Group) of central Japan
Montirictus kuwajimaensis Matsuoka, Kusuhashi & Corfe, 2016  *This image is copyright of its original author Credit: Seishi Yamamoto/Hiroshige Matsuoka Abstract: "We describe tritylodontid remains from the Lower Cretaceous Kuwajima Formation (Tetori Group) in central Japan as representing a new genus, Montirictus kuwajimaensis, gen. et sp. nov. Montirictus is a medium-sized tritylodontid genus characterized by upper cheek teeth having the cusp formula 2-2-2 with subequal cusps, buccal and lingual cusps retaining a crescentic shape with both buccal and lingual ridges anteriorly, and ‘V’-shaped buccolingual cross-sections of two anteroposterior grooves between the three cusp rows. Tentative dating of the Kuwajima Formation to the Barremian–Aptian makes it the stratigraphically youngest representative of a long-lived, globally distributed and abundant mammaliamorph lineage and extends the known geographic range of tritylodontids." Other articles related: Mammal-like reptile survived much longer than thought
Old news, but very interesting.
700,000-Year-Old Horse Found in Yukon Permafrost Yields Oldest DNA Ever Decoded NOVEMBER 19, 2013 • UPDATED MARCH 3, 2017 —BY BLAKE DE PASTINO  *This image is copyright of its original author The frozen remains of a horse more than half a million years old have reluctantly given up their genetic secrets, providing scientists with the oldest DNA ever sequenced. The horse was discovered in 2003 in the ancient permafrost of Canada’s west-central Yukon Territory, not far from the Alaskan border. And although the animal was dated to between 560,000 and 780,000 years old, an international team of researchers was able to use a new combination of techniques to decipher its genetic code. (Read about another recent find: “Wyoming Cave Yields a Trove of Ice Age Fossils — and Ancient Animal DNA“) Among the team’s findings is that the genus Equus — which includes all horses, donkeys, and zebras — dates back more than 4 million years, twice as long ago as scientists had previously believed. The Przewalski’s Horse, which lives on the steppes of central Asia, likely deviated from the lineage leading to modern domesticated horses some 50,000 years ago. (Photo: Joe Ravi)  *This image is copyright of its original author “When we started the project, everyone — including us, to be honest — thought it was impossible,” said Dr. Ludovic Orlando of the University of Copenhagen, who coordinated the research, in a statement to Western Digs. “And it was to some extent, with the methods available by then. So it’s clearly methodological advances that made this possible.” Orlando and his colleagues published their findings this summer in the journal Nature; he discussed them today in a lecture at The Royal Society, London. Previous to this, the oldest genome ever sequenced was of a 120,000-year-old polar bear — no small feat considering that the half-life of a DNA molecule is estimated to be about 521 years. By this reckoning, even under the best conditions, DNA could remain intact for no more than 6.8 million years. (See this recent amazing find: “First Columbian Mammoth With Hair Discovered on California Farm“) But Orlando’s team was able to make the most of what they had for a number of reasons, he said. The fact that the remains were frozen helped slow the rate of decay. But they also “targeted specific DNA preservation niches,” he said, like the protein called collagen found in the animal’s bones, which is more DNA-rich than other tissues. “But also we pioneered the usage of what is called true Single Molecular Sequencing that basically reads through molecules as they stand, without further manipulation,” Orlando added. By tracking a full, single DNA molecule, the team was able to avoid having to “amplify” fragments, which can often introduce errors. Two pieces of the 700,000 year-old horse metapodial bone, just before being extracted for ancient DNA. Photo: © Ludovic Orlando  *This image is copyright of its original author To get a better sense of what this new, ancient genome held, Orlando’s team compared it against that of a 43,000-year-old horse, plus modern domestic horse breeds, and finally the Przewalski’s horse, an equid that makes its home on the Asian steppes and holds the title as the last surviving population of wild horses. These full-genome comparisons allowed the scientists to construct “a molecular clock” that can reveal benchmarks in the horse’s evolutionary history, Orlando said. And first among its revelations is that the shared ancestor of all horses, donkeys, and zebras lived more than 4 million years ago. “So basically we know that members of the genus Equus are at least twice as old as previously believed,” he said. The comparisons also shed light on genetic variations, and therefore population size, over time, Orlando noted, revealing “bursts of expansion” during cooler periods as grasslands grew, and contractions in size during times of warming. (Learn more about how global warming affected the size of prehistoric mammals: “Prehistoric Global Warming Caused Dwarfism in American Mammals, Fossils Show“) The next, most obvious subject for these DNA-decoding techniques are early human ancestors, he said. Methods like those used on the ancient horse could be applied to determine, for example, how human species like Homo heidelbergensis may have been related genetically to Homo neandertalensis and modern humans, he said. (Explore the history of humans and horses: “Ice Age Cave Dwellers in Oregon Lived Among Extinct ‘Stout-Legged’ Horses, Fossils Show“) “Basically genomes of that age will enable us to test the validity of the many paleontological species in our family tree,” he said, “and to determine how they relate to each other, and whether they exchanged genes or not.” “It’s not the future,” he said of whether this technology is in reach. “It’s basically already there.” Orlando and his colleagues report their findings in the journal Nature.
Earliest Mysticete from the Late Eocene of Peru Sheds New Light on the Origin of Baleen Whales
Mystacodon selenensis Lambert et al., 2017  *This image is copyright of its original author Reconstruction credits: Alberto Gennari  *This image is copyright of its original author Figure 1 Cranium, Mandible, and Teeth of Mystacodon selenensis gen. et sp. nov. MUSM 1917 Cranium in dorsal (A), left lateral (B), and ventral © views; detail of left posterior lower teeth in lateral view (D); left mandible in lateral (E) and dorsal (F) views; and three detached anterior lower teeth (from left to right: incisor, incisor/canine, and ?p1) in lingual or labial and occlusal views (G). aof, antorbital foramina; apm, antorbital process of maxilla; bn, bony nares; C, upper canine; c, lower canine; cp, coronoid process; ep, embrasure pit; I1–I3, upper incisors; i1–i3, lower incisors; iop, infraorbital plate; ju, jugal; la, lacrimal; M1 and M2, upper molars; m1–m3, lower molars; maf, mandibular fossa; mf, mental foramina; mg, mesorostral groove; mx, maxilla; na, nasal; nc, nuchal crest; P1–P4, upper premolars; p1–p4, lower premolars; pa, parietal; pmx, premaxilla; prpf, preorbital process of frontal; pspf, postorbital process of frontal; sq, squamosal; sym, mandibular symphysis; zpm, zygomatic process of maxilla; zyg, zygomatic process of squamosal. Scale bars for (A)–©, (E), and (F), 200 mm; for (D), 20 mm; and for (G), 10 mm. See also Figures S2 and S4 and Table S2. Highlights
Summary "Although combined molecular and morphological analyses point to a late middle Eocene (38–39 million years ago) origin for the clade Neoceti (Odontoceti, echolocating toothed whales plus Mysticeti, baleen whales, and relatives), the oldest known mysticete fossil dates from the latest Eocene (about 34 million years ago) of Antarctica [1, 2]. Considering that the latter is not the most stemward mysticete in recent phylogenies and that Oligocene toothed mysticetes display a broad morphological disparity most likely corresponding to contrasted ecological niches, the origin of mysticetes from a basilosaurid ancestor and its drivers are currently poorly understood [1, 3, 4, 5, 6, 7, 8]. Based on an articulated cetacean skeleton from the early late Eocene (Priabonian, around 36.4 million years ago) of the Pisco Basin, Peru, we describe a new archaic tooth-bearing mysticete, Mystacodon selenensis gen. et sp. nov. Being the geologically oldest neocete (crown group cetacean) and the earliest mysticete to branch off described so far, the new taxon is interpreted as morphologically intermediate between basilosaurids and later toothed mysticetes, providing thus crucial information about the anatomy of the skull, forelimb, and innominate at these critical initial stages of mysticete evolution. Major changes in the morphology of the oral apparatus (including tooth wear) and flipper compared to basilosaurids suggest that suction and possibly benthic feeding represented key, early ecological traits accompanying the emergence of modern filter-feeding baleen whales’ ancestors." Other articles related: This ancient whale likely sucked prey into its mouth like a giant vacuum cleaner 36m-year-old fossil discovery is missing link in whale evolution, say researchers Baleen whales' ancestors were toothy suction feeders
A mitogenomic timetree for Darwin’s enigmatic South American mammal Macrauchenia patachonica Westbury et al., 2017
 *This image is copyright of its original author Figure 3: Dated mitogenomic phylogenetic tree. Posterior probabilities and bootstrap values are indicated on the tree branches. The purple node bar represents the 95% CI for the Panperissodactyla clade divergence date based on the combination of all four calibrations used in this study. Scale bar represents time in millions of years. Grey vertical lines represent five million year intervals. Abstract: "The unusual mix of morphological traits displayed by extinct South American native ungulates (SANUs) confounded both Charles Darwin, who first discovered them, and Richard Owen, who tried to resolve their relationships. Here we report an almost complete mitochondrial genome for the litoptern Macrauchenia. Our dated phylogenetic tree places Macrauchenia as sister to Perissodactyla, but close to the radiation of major lineages within Laurasiatheria. This position is consistent with a divergence estimate of ∼66 Ma (95% credibility interval, 56.64–77.83 Ma) obtained for the split between Macrauchenia and other Panperissodactyla. Combined with their morphological distinctiveness, this evidence supports the positioning of Litopterna (possibly in company with other SANU groups) as a separate order within Laurasiatheria. We also show that, when using strict criteria, extinct taxa marked by deep divergence times and a lack of close living relatives may still be amenable to palaeogenomic analysis through iterative mapping against more distant relatives." |
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