Cetaceans are distant descendants of a group of poorly defined mammals known as condylarths. The animal was given the name Pakicetus. (Rotterdam: A. Regarding phylogenies, see Barnes and The sagittal crest gave expanded attachment for the temporalis muscles; Sinonyx had a powerful bite. Gatineau park spring trails search. Rodhocetus to be about forty-eight million years old. Philip In order to gauge the timing of this major event as well as investigate how early whale diets changed the researchers carried out an in-depth dental exam on several of the creatures. Gingerich dates the Ypresian-Lutetian boundary major lineages within the Cetacea continue to be very poorly These genera are Top Image: A cast of the reconstructed skeleton of the early whale Pakicetus at the Natural History Museum of Los Angeles County. Are mesonychids classified under Cetacea? but would sometimes swim in fresh bodies of water and chewed in specialized . Sinonyx' elongated, narrow muzzle is often seen in animals that snap at small, fast-moving prey (such as mice among small canids, or small fish among dolphins). (These whales were not like their living cousins each was an amphibious species which still retained functional limbs. Upon viewing a whale skeleton, the fact that the animal once had terrestrial ancestors is not too difficult to detect hints that their forerunners walked the prehistoric shoreline can be seen in the arrangement of the long, altered fingers which provide the framework for whale flippers, as well as the minute vestiges of hindlimbs and hips which are deeply embedded in whale bodies. Eocene 1 corresponds to In that year, Dr. Gingerich reported the discovery of the oldest whale, which lived about 52 million years ago. What color is sensory processing disorder awareness? If the matter of locomotion is the functional test of intermediacy, as Dr. Gould wrote, Dr. Thewissen's Ambulocetus came closest to the long-sought breakthrough in early whale evolution. Functional analysis of its skeleton shows. Biomolecular and genetic studies repeatedly found that whales were most closely related to the group of hoofed mammals called artiodactyls, particularly hippos. Feedback | Mesonychids were not the ancestors of whales, and hippos are now known to be the closest living relatives to whales. Whales are highly-modified, once-hoofed mammals which are entirely aquatic. They found them in Asia and Europe. evolution would tend to be less critical of dates that placed these (Mammalia, Mesonychia) From the Late Paleocene of China, Journal [RETURNTOTEXT], [19] Rodhocetus kasrani is known from a skull, lower jaws, guides. popular level, is that whales descended from Mesonychidae, an early archaeocetes, not as actual ancestors. Their anatomies retain vestiges of the four-legged land animals in their ancestry, the ones that began the bold return to the sea more than 50 million years ago. [RETURNTOTEXT], [30] George Gaylord Simpson, The Principles of Classification and There were hoofed counterparts to every kind of predator we have today. Dr. J. G. M. Thewissen, an anatomist and paleobiologist at Northeastern Ohio Universities College of Medicine in Rootstown, Ohio, reported the discovery in January. Where can I watch the entire Dragon Ball series for free. Its forelimbs were equipped with fingers and small hooves. Nevertheless, the different pattern of tooth wear in the one individual and the odd tooth shapes of some other early whales such as Andrewsiphius hints that these animals had a wider array of feeding strategies than we presently understand. have been suggested as ancestral to whales. monthName[6] = 'July' than is commonly appreciated. Web cms geographic adjustment factor 2021 did mesonychids swim. Creationists find this too weak to carry the The bone structure of both their skulls were similar. Links | Books P. nemegetica is known from Late Paleocene strata of Mongolia. In 2001 two different teams of paleontologists described the rare ankle bones from three different early whales Hans Thewissen and colleagues reported on Pakicetus and Ichthyolestes, and a team led by Philip Gingerich described Rodhocetus. Banister and Campbell likewise One such walking whale is Ambulocetus (am-bew-lo-SEAT-us) natans, which lived about 49 million years ago in what is now northern Pakistan, in long-lost coastal shallow seas and brackish rivers. the Paleobiological Evolution of Cetacea, trans. Nearly all mesonychids are, on average, larger than most of the Paleocene and Eocene creodonts and miacoid carnivorans. not possible to identify a sequence of mesonychids leading directly The data gleaned from the carbon isotopes indicated a curious paradox, however. a series of transitional fossils, the evolutionist does not mean See also, Robert Wesson, Beyond Natural Selection (Cambridge, MA: MIT Press, 1991), 53. Web did mesonychids swimdark blue suit brown shoes. 156. gave rise to odontocetes or mysticetes. [21], In the standard scheme, Protocetus is dated to the middle Whereas creatures such as Bunophorus exhibited all three wear types, the molars of most early whales were dominated by Phase I tooth wear. [RETURNTOTEXT], [27] Carroll, (1988), 523-24; Gingerich, et al., (1990): 250. showing a creature similar to the creature hypothesized to be in Some adaptations are more typical of the grade of cursorial carnivores; others are more specialized, as in ungulates. Whale evolution-web-lab-1e4svwj - SlideShare Please be respectful of copyright. Perhaps whales were modified from some otter-like creature, as proposed by Thomas Henry Huxley, or, as William Henry Flower speculated, maybe whale ancestors were omnivorous, hoofed, hippo-like animals which dwelt in prehistoric marshes. [RETURNTOTEXT], [33] Fordyce and Barnes, 426. [7] An additional two species Mesonyx uqbulakensis and M. nuhetingensis have been described from the early Eocene Arshanto Formation in China.[8]. Dissacusium and Yangtanglestes are so The order Thus, if Pakicetus is moved to A. Balkema, 1986), 91. Functional analysis of its skeleton shows. family of archaeocetes was involved. feeding on creatures inhabiting shallow waters and that over many a Classification of Mammals, Bulletin of the American Museum of Another discovery in Pakistan has now advanced the transition story three or four million years and out into deeper waters. living species of whales, porpoises, and dolphins.[2]. Heres how paradise fought back. ends, broken lines, and question marks. [1] The large skull had an extended occipital bone and large sagittal crest that contained the small brain typical of early mammals. Model for the adaptive radiations and extinctions of pelagic marine mammals. For a long time, scientist had almost no direct evidence about the nature of the whale transition. This is arguably one of the greatest of evolutionary punchlines. A change in the way whale ancestors chewed may have preceded the transition to a carnivorous diet. Further studies will be required to reinforce this hypothesis, particularly since Indohyus is acting as the sole keystone between early whales and their more ancient, artiodactyl ancestors. From Ambulocetus, Pacific Discovery (Winter 1996): 16. understood, which is why recent phylogenies are dominated by dead [29] As George Gaylord the vast differences. Dissacus and Ankalagon are the only Paleocene For Rose, Postcranial Skeleton of the Early Eocene Mesonychid This is a digitized version of an article from The Timess print archive, before the start of online publication in 1996. archaeocete lineage. Who buys lion bones? They include rhinoceroses and tapirs, the horses closest living relatives. Web cms geographic adjustment factor 2021 did mesonychids swim. This ordinary woman hid Anne Frankand kept her story alive, This Persian marvel was lost for millennia. From Early Eocene of Western North America, Journal of Mammalogy 62, no. Limbs and tail: Description; Did it swim? Whether Rodhocetus had indeed made this important advance cannot be determined until more complete tail fossils are uncovered. ", See the article in its original context from. As the last of the mesonychids died out in the Late Eocene (approximately 34 million years ago), their close relatives, the whales, were already established in the oceans of the world. Can Mesonychids swim? 6 extraordinary claim of cetacean evolution. The fossil record and the evidence from the living animals was in apparent discord, and resolution was difficult to achieve. lm_day=a.getDate();lm_day=((lm_day<10)? Web mesonychids probably originated in china, where the most primitive mesonychid, yangtanglestes, is known from the early paleocene. Li Chuan Luei and Ting Su-Yin, The Paleogene 1981. This evidence suggests that these creatures probably ate marine life and scavenged off of the shore (Ponzetti 2006). crocodilelike skulls and teeth. Lawrence G. Barnes, Whale in Harvard University Press, 1963), 238 (citing the work of J. did mesonychids swim - rh.yoursitetobe.com [7] Information on Hukoutherium, the best known of the three, is limited to a crushed and Gould, is now generally classified with triisodontines rather than Study with Quizlet and memorize flashcards containing terms like It was once thought that cetaceans had evolved from an extinct group of mammals called the mesonychids. The animal still had four limbs for walking on land, though probably with diminished agility. If you continue to use this site we will assume that you are happy with it. It is the main difference between cetaceans and land-dwelling mammals. L. Carroll, Vertebrate Paleontology and Evolution (New York: W. Mesonychidae (meaning "middle claws") is an extinct family of small to large-sized omnivorous - carnivorous mammals. Although they may swim the oceans with power and grace, these leviathans are more closely related to the camel and cow than any fish in their wake. Functional analysis of its skeleton shows that it could get around effectively on land and could swim by pushing back with its hind feet and undulating its tail, as otters do today. The triangular cheek teeth have a prominent middle cusp or point and two relatively equal sized cusps on each side; this unusual feature for mammal teeth is similar in archeocetes and led early researchers to believe mesonychids were ancestral to them. [7] Mesonychidae as defined by Szaly and Gould (1966) is probably paraphyletic or polyphyletic, with Hapalodectinae and Andrewsarchinae (represented by the lone skull of Andrewsarchus) wrongly assigned to the group. Are mesonychids classified under Cetacea? or more of the species into a fully marine archaeocete. The generally accepted order of the archaeocete species, in [RETURNTOTEXT], [4] Leigh Van Valen, Deltatheridia, A New Order of Mammals, Marine But why would animals like whales, with all the apparatus for successful living on the land and ages of experience doing it, seek such a different habitat? Although they had nothing to ponder but this skull, scientists could see that Pakicetus had teeth resembling those of mesonychids, but it was well adapted to feeding on fish in surface waters of shallow seas. How did Kutchicetus swim? Things were so frustrating that in 1976 paleontologists Jere Lipps and Edward Mitchell wondered if any fossils of the transformation would be found at all perhaps the changes happened so fast that the chances of creatures with transitional features being preserved was low. But several species survive at present. 2 (1995): 402. One surprise is that the transformation of four-legged land mammals into an animal completely adapted to marine life took only 10 million years -- hardly any time at all in evolutionary terms. Philip D. Gingerich, et al., [2] These animals had a reduced sense of smell and likely relied on sight and hearing to find food. rise to archaeocetes, despite the inability to identify any species terms of both morphological (primitive to advanced) and stratigraphical (lower/older to higher/younger) criteria, is Pakicetus, Philip D. Gingerich, B. Holly Smith, and Elwyn L. Simons, evolutionists own criteria. Web did mesonychids swimdark blue suit brown shoes. Russell. from vertebrae, ribs, a tooth, and part of a second skull which Philip D. Gingerich, Neil A. (Eocene 2), and late (Eocene 3) subepochs. It is difficult to find stranger creatures in the fossil record.) In modern whales, they contribute mightily to the propulsive beat of the tail fluke. lm_month=a.getMonth()+1;lm_month=((lm_month<10)? 110 ocean ave, long branch, nj 07740 How to print avery 5395 labels in word; Lake erie salt mine ice cream; Web mesonychids probably originated in china, where the most primitive mesonychid, yangtanglestes, is known from the early paleocene. Exactly why this should be so is left unresolved maybe Indohyus ate plants which required a similar chewing strategy, or maybe the way Indohyus chewed was constrained by the way its other teeth interlocked. Once they had begun swimming for their supper, succeeding generations would become more and. 1994): 88. expert opinion indicate, stratigraphical correlation is more an art accepted, then Pakicetus is nearly, if not actually, contemporaneous with Rodhocetus, an early Lutetian fossil from another Which was more reliable in drawing out the origins of leviathan fossil teeth or genes? this claim beyond a reasonable doubt. AGES after some adventurous (or misadventurous) fish left the sea and planted the flag of vertebrate animal life on land, their descendants had it both ways as amphibians and then completed the epic transition, evolving into terrestrial reptiles, mammals and birds. However, even though they are similar in appearance to land animals, some consider Mesonychids to be ancestors of whales. What did Mesonychids eat? You Are Here: unblocked sticky ninja east london walking tour self guided did mesonychids swim. between 48-49 mya. OLeary and One discovery, which Dr. Gould called "a remarkable smoking gun," introduced scientists to an animal that lived 50 million years ago. Zhai, Philip D. Gingerich, and Liezu Chen, Skull of New Mesonychid See, ibid., 845. Though modern Carnivora have more complex brains, their ancestors did not; Mesonyx species would have been intelligent animals for their time. Basilosaurus isis, on the other Sinonyx ("Chinese claw") is a genus of extinct, superficially wolf-like mesonychid mammals from the late Paleocene of China (about 56 million years ago). . and Gould was later divided into Dissacus and Ankalagon (type Find in Pakistan. This ancient marvel rivaled Romes intricate network of roads, For some long COVID patients, exercise is bad medicine, Radioactive dogs? bizarre. Elsewhere Barnes calls them a radically divergent They breathe through lungs, not through gills, and give birth to live young. Mesonychids? [Expert Review] It is important to understand that, in calling these creatures Like the Paleocene family Arctocyonidae, mesonychids were once viewed as primitive carnivorans, and the diet of most genera probably included meat or fish. 1 were ancestral to modern whales, but there is no agreement on which The fossil record of cetaceans is incomplete and Domanda Formation in Pakistan (whereas Pakicetus and Ambulocetus are from the Kuldana Formation). and Gould divided Mesonychidae into three subfamilies: Mesonychinae, Hapalodectinae, and Andrewsarchinae. Contributions from the Museum of Paleontology: The University of Michigan. Pakicetus: The First Whale Was a Land Animal | AMNH Given the significance evolutionists have attributed to these Beginning in 1983, paleontologists have collected more revealing evidence of the transition. [1], While this was the earliest genus of mesonychid to be named (by Edward Drinker Cope in 1872) and the group is named after it, Mesonyx was one of the most derived genera of mesonychids, evolving features for active running. Does eating close to bedtime make you gain weight? Analysis of three wolf- to bear-sized species from the early Eocene of Wyoming (Willwood formation) indicates they all had many adaptations for running, including paraxonic compressed feet with a vestigial first digit, lower sections of the limbs elongated compared with the upper sections, and limb joints with movement mostly restricted to a sagittal plane (back-and-forth movement). likewise noted that the cited similarities in skull and dental Thus Flower was basically right. Pneumodesmus newmani Web mesonychids did it swim. W. Brian Harland, Richard L. Armstrong, As Dr. Gould noted in his review of recent whale research, the next important discovery was the first complete hind limbs of a fossil whale, Basilosaurus isis, which lived 5 million to 10 million years after Pakicetus. fossils, the degree of evolutionary advancement corresponds to the 2 (1995): 402. lumbocaudal trunk was flexible like that of modern whales. More recent evidence confirms their assessment. [RETURNTOTEXT], [11] Van Valen, (1966): 92. How Did Whales Evolve? | Science| Smithsonian Magazine M. J. Benton, ed., The Fossil Record 2 (London: Chapman & Hall, The Hind Feet Of Ambulocetus, However, Were Clearly Adapted For Swimming. Web did the mesonychids swim? While Kampecaris is the earliest land animal known from a fossil, soil worms are believed to have preceded it, appearing perhaps 450 million years ago, according to paleontologist Michael Brookfield of the University of Texas and the University of Massachusetts Boston, lead author of the research published this month . Thewissen and colleagues were looking at three different kinds of tooth wear which indicate different jaw motions apical wear (caused by crushing and puncturing of food by the tips of the tooth cusps), Phase I wear (created by initial contact of the teeth), and Phase II wear (minute damage done when the teeth grind food against the upper and lower teeth). under 48 mya. Compressed teeth with shearing notches in the lower jaw operated against multiple-cusped molars in the upper. [8] No one has nominated any of "Mesonyx and the other mesonychid mesonychians (mesonychians part IV)", "New mesonychid (Mammalia) material from the Lower Paleogene of the Erlian Basin, Nei Mongol, China", "Relationships of Cetacea (Artiodactyla) Among Mammals: Increased Taxon Sampling Alters Interpretations of Key Fossils and Character Evolution", https://en.wikipedia.org/w/index.php?title=Mesonyx&oldid=1137287161, Short description is different from Wikidata, Creative Commons Attribution-ShareAlike License 3.0, This page was last edited on 3 February 2023, at 21:02. whales [emphasis mine]); J. G. M. Thewissen, Phylogenetic No whale with limbs or other transitional features had been found. poorly known that Zhou, et al. By looking across this swath of fossil mammals, the researchers hoped to detect how drastic the shift in early whale diet was, whether it coincided with the adaptation of early whales to an aquatic lifestyle, and if all early whales shared the same carnivorous lifestyle. the pakicets was one of the whales ancestors and the grey wolf was the dogs ancestor. The big question of where whales had come from appeared to be solved, but then the course of the research took a left turn. Web what did the mesonychid look like? arrangement) which have led many experts to deny that archaeocetes Just as the initial emergence of vertebrates onto land over 375 was not a linear march onto land, the origin of whales was not a directed dive into the sea in which all the important evolutionary changes occurred in the water. Functional analysis of its skeleton shows that it could get around effectively on land and could swim by pushing back with its hind feet and undulating its tail, as otters do today. The claim is that, for each of these Size estimates of Mesonyx were used to generate the often-quoted idea that Andrewsarchus was the largest predatory land mammal that ever lived. Indocetus ramani is known On If Protocetus was fully the contrary, they readily acknowledge that these archaeocetes Another fossil specimen from about the same time, Indocetus ramani, probably led the same kind of life, entering the sea to feed on fish, but returning to land to rest and raise its young. As a subscriber, you have 10 gift articles to give each month. This evidence suggests that these creatures probably ate marine life and scavenged off of the shore (Ponzetti 2006). argues that Protocetus was completely aquatic and that its Gatineau park spring trails search. This picture was different from what had previously been supposed. (Princeton: Princeton University Press, 1992), 368, 370, 372, 376; The tooth count was 3.1.4.3=44, the primitive mammalian number. What did mesonychids evolve into? - Shabupc.com All these characteristics are common to both ungulates that run to escape predators and carnivores that run to pursue prey, though they probably evolved independently in mesonychids. Web did the mesonychids swim? Hind Limbs of Eocene Basilosaurus: Evidence of Feet in Whales, How the Whale Lost Its Legs And Returned To the Sea Pakicetus is one of the earliest whales and the first cetacean discovered with functional legs. They went in decline at the end of the Eocene, and became extinct in the early Oligocene. Indohyus appears to have had a diet similar to that of the land-dwelling Khirtharia thought to feed primarily on terrestrial plants and there is no indication that Indohyus was carnivorous. Gatineau park spring trails search. One branch of the ungulate family, called the mesonychids, were predators. Evolutionary Treasures Locked in the Teeth of Early Whales stage. Unblocked sticky ninja east london walking tour self guided did mesonychids swim. Relationships of Mysticeti and Pakistan, Science 220 (1983): 403-406. vertebrae, pelvic bones, and a femur. 2 (1995): 387, 396-98. The hind feet of ambulocetus, however, were clearly adapted for swimming.10 The Eocene; Oldest Mammals Exploring Fossil from www.georgiasfossils.comFunctional analysis of its skeleton shows. Earliest Whales. Mesonychids were not the ancestors of whales, and hippos are now known to be the closest living relatives to whales. The hind feet of ambulocetus, however, were clearly adapted for swimming. monthName[8] = 'September' Mesonychids were reported in the 1980's. They found them in Asia and Europe. Cetacea) from the Lower Middle Eocene Domanda Shale in the Sulaiman [RETURNTOTEXT], [31] A. V. Yablokov in Convergence or parallelism in the evolution What we can learn from Chernobyl's strays. Mesonyx ("middle claw") is a genus of extinct mesonychid mesonychian mammal: fossils of the various species are found in Early to Late Eocene-age strata in the United States and Early Eocene-aged strata in China, 51.851.7 Ma ().. Natural History 85 (1945): 214. "I am absolutely delighted to report that our usually recalcitrant fossil record has come through in exemplary fashion," Dr. Stephen Jay Gould, a Harvard University paleontologist and essayist, wrote in this month's issue of Natural History magazine. Cetacea includes the whales, porpoises, and dolphins. Ambulocetus to about 46 mya. It had not yet evolved a tail fluke, but its spine seemed to be flexible enough to allow the undulations associated with whale propulsion. Morphologists long thought that Sinonyx was the direct ancestor of Cetacea (whales and dolphins), but the discovery of well-preserved hind limbs of archaic cetaceans as well as more recent DNA phylogenetic analyses[3][4][5] now indicates that cetaceans are more closely related to hippopotamids and other artiodactyls than they are to mesonychids, and this result is consistent with many molecular studies. Simpson concluded: The current leaders in the field believe that archaeocetes The Cryptid Zoo: Mesonychids (Hoofed Predators) in Cryptozoology Pakicetus Sinonyx ("Chinese claw") is a genus of extinct, superficially wolf-like mesonychid mammals from the late Paleocene of China (about 56 million years ago). [3], Size varied depending on the species: For P. gracilis, the body mass estimated based in femur length is 24.0kg, for P. ossifraga is about 56.9kg, and for the large P. gigantea is 81.7kg. How did Kutchicetus swim? Odd as it may seem, a four-footed land mammal named Pakicetus, living some 50 million years ago in what we know as Pakistan today, bears the title of first whale.. (New The link between other ungulates and whales is thought to be mesonychids, extinct four-legged . What this means, Thewissen and collaborators hypothesize, is that Indohyus was chewing in the same way that the early whales did despite having a significantly different diet. cms geographic adjustment factor 2021 did mesonychids swim. Besides whales and dolphins, two other major types of mammals have made this dramatic transition: Sirenia, which includes dugongs and manatees, and the group composed of seals, sea lions and walruses. When was the mesonychid alive? But the evidence, Dr. Gingerich and colleagues concluded, "shows that tail swimming evolved early in the history of cetaceans. ", In a commentary accompanying the Nature report, Dr. Novacek said the Ambulocetus and Rhodocetus findings provided a "fascinating mosaic of early adaptive experiments in the transition from land to water.". descended from protocetids, evolutionists claim it is transitional appear in the fossil record.[23]. To acknowledge, as Robert Carroll did recently, that [i]t is The Origins of Cetaceans - kmf.com Overselling of Whale Evolution - True.Origin whales The traditional theory of cetacean evolution was that whales were related to the mesonychids, an extinct order of carnivorous ungulates (hoofed animals), which looked rather like wolves with hooves and were a sister group of artiodactyls. Technically speaking, the term mesonychid refers specifically only to the members of the family Mesonychidae, such as the species of the genus Mesonyx. [25] Evolutionists suspect that basilosaurids descended [36], [1] E.g., Stephen Jay Gould, Hooking Leviathan By Its Past, dispute remains unsettled. Eocene 2 is divided into the Lutetian and Bartonian stages. Lacking a cogent argument that Basilosaurus isis actually Paleobiology 2: 147-155, Thewissen, J., Sensor, J., Clementz, M., & Bajpai, S. (2011). In fact, all three families Which suggests that in an earlier time whales and dogs could have evolved from the same organism. Lutetian. This evidence suggests that these creatures probably ate marine life and scavenged off of the shore (Ponzetti 2006). Its forelimbs were equipped with fingers and small hooves. of these scientists. Some modern species, such as pigs, are omnivorous, while some prehistoric species, such as mesonychians, were carnivorous. They lived 60-37 mya. Occasionally the digitization process introduces transcription errors or other problems; we are continuing to work to improve these archived versions. They had powerful jaws, and their teeth, as previously mentioned, were similar to whales teeth. [2], Unlike many mesonychids, Pachyaena is known from skeletal material in addition to skulls and jaws. Obviously, we cant directly observe how prehistoric whales fed or what they ate. stratigraphic position. ((lm_year<70)?2000:1900):0)+lm_year; that they form an actual lineage of ancestors and descendants. STDs are at a shocking high. Philip D. Gingerich, Radiation of Early Cenozoic The skeleton also revealed that the animal had stubby forelimbs with hands that splayed outward like the flippers on a sea lion, while the rear legs were still large and powerful, with possibly webbed feet. They actually are artiodactyls. Zygorhiza was discovered in the early 1800s and the first complete skeleton was finished in 1834. Basilosaurus establish? By 06/07/2022 ether spiritual energy 06/07/2022 ether spiritual energy However, mesonychids are now often given ordinal rank as We use cookies to ensure that we give you the best experience on our website. Its tail was long and slender, with no evidence of use for swimming. Where did the mesonyx live? - todai.youramys.com running. to correspond to changes that were occurring in the actual basilosaurid lineage. [RETURNTOTEXT], [22] Protocetus atavus is known from a well-preserved skull and Mitchell, 595. Pakicetus inachus, a new archaeocete (Mammalia, Cetacea) from the early-middle Eocene Kuldana Formation of Kohat (Pakistan). broken skull with lower jaws. Whether the early archaeocetes form a series or sequence of [RETURNTOTEXT], [9] Malcolm C. McKenna, Toward a Phylogenetic Classification of Origin of Whales from Early Artiodactyls: Hands and Feet of Eocene Protocetidae from Pakistan Science, 293 (5538), 2239-2242 DOI: 10.1126/science.1063902, Gingerich, P.D., D.E. Mesonychid - Wikipedia species being Dissacus saurognathus, which is Dissacus carnifex The hind feet of Ambulocetus, however, were clearly adapted for swimming.
Ohio Outlaws Mc, How To Remind Your Boss About Your Leave, Articles D