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Cetaceans (Talk.Origins)

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Response Article

This article (Cetaceans (Talk.Origins)) is a rebuttal regarding a supposed transitional form published by the Talk.Origins Archive under the title Transitional Vertebrate Fossils FAQ.


Response to Cetaceans (whales, dolphins)


CreationWiki response:

General

(Talk.Origins quotes in blue)

  • Eoconodon or similar triisodontine arctocyonids (early Paleocene) Unspecialized condylarths quite similar to the early oxyclaenid condylarths, but with strong canine teeth (showing first meat-eating tendencies), blunt crushing cheek teeth, and flattened claws instead of nails.
  • Microclaenodon (mid-Paleocene) -- A transitional genus intermediate between Eoconodon and the mesonychids, with molar teeth reorganizing in numerous ways to look like premolars. Adapted more toward carnivory.

There is insufficient information on Eoconodon and Microclaenodon for an independent analysis.

  • Dissacus (mid-Paleocene) -- A mesonychid (rather unspecialized Paleocene meat-eating animal) with molars more like premolars & several other tooth changes. Still had 5 toes in the foot and a primitive plantigrade posture.

Dissacus and Microclaenodon are classified as mid-Paleocene, so they would be contemporary and their order in such a list is arbitrary at best.

The skeleton and skull are sufficiently incomplete to make the reconstruction questionable. Dissacus represents #2 on this list and the dark areas in the drawings of the skeleton and skull are the actual bones. The reconstruction looks like a dog.

  • Hapalodectes or a very similar mesonychid (early Eocene, around 55 Ma) -- A small mesonychid with very narrow shearing molars, a distinctively shaped zygomatic arch, and peculiar vascularized areas between the molars. Probably a running animal that could swim by paddling its feet. Hapalodectes itself may be just too late to be the whale ancestor, but probably was a close relative of the whale ancestor. Says Carroll (1988): "The skulls of Eocene whales bear unmistakable resemblances to those of primitive terrestrial mammals of the early Cenozoic. Early [whale] genera retain a primitive tooth count with distinct incisors, canines, premolars,, and multirooted molar teeth. Although the snout is elongate, the skull shape resembles that of the mesonychids, especially Hapalodectes...."

Dissacus is classified as mid-Paleocene and Hapalodectes is classified as early Eocene. There is no reference to the late-Paleocene leaving a 5 Ma gap.

Hapalodectes and Dissacus are probably the same kind of animal and unrelated. In addition, they know that Hapalodectes is not a whale ancestor, but naturally this ancestor must have existed according to evolution.

  • Pakicetus (early-mid Eocene, 52 Ma) -- The oldest fossil whale known. Same skull features as Hapalodectes, still with a very terrestrial ear (tympanic membrane, no protection from pressure changes, no good underwater sound localization), and therefore clearly not a deep diver. Molars still have very mesonychid-like cusps, but other teeth are like those of later whales. Nostrils still at front of head (no blowhole). Whale- like skull crests and elongate jaws. Limbs unknown. Only about 2.5 m long. This skull was found with terrestrial fossils and may have been amphibious, like a hippo.

Pakicetus is known mainly from its skull and a fragmented skeleton. Talk Origins states: "Same skull features as Hapalodectes", and the skeleton found is also similar to Hapalodectes so Hapalodectes and Pakicetus seem to be varieties of the same kind of animal.

  • Ambulocetus natans (early-mid Eocene, 50 Ma) -- A recently discovered early whale, with enough of the limbs and vertebrae preserved to see how the early whales moved on land and in the water. This whale had four legs! Front legs were stubby. Back legs were short but well-developed, with enormous broad feet that stuck out behind like tail flukes. Had no true tail flukes, just a long simple tail. Size of a sea lion. Still had a long snout with no blowhole. Probably walked on land like a sea lion, and swam with a seal/otter method of steering with the front feet and propelling with the hind feet. So, just as predicted, these early whales were much like modern sea lions -- they could swim, but they could also still walk on land.

Ambulocetus natans is based on fragmented evidence. A more complete skeleton has been found, but even it lacks some critical parts, such as the shoulder and upper fore-limb. This makes the whole reconstruction questionable. But as we have seen, evolutionists do not require much in the way of fossil remains to reconstruct an animal favorable to evolution. Since the front legs are incomplete it is likely that Talk Origins' description is more a result of evolutionary assumptions than reality.

The only real similarities that Ambulocetus natans has with whales is nose features that allowed it to swallow underwater, and ear structures that allowed them to hear well underwater. Ambulocetus natans seems to have spent much time both on land and under water. But that does not make it transitional.


  • Rodhocetus (mid-Eocene, 46 Ma) -- Another very recent (1993) fossil whale discovery. Had hind legs a third smaller than those of A. natans. Could probably still "waddle" a bit on land, but by now it had a powerful tail (indicated by massive tail vertebrae) and could probably stay out at sea for long periods of time. Nostrils had moved back a bit from the tip of the snout.

Rodhocetus.gif

Note this quote from Talk Origins: "Had hind legs a third smaller than those of A. natans." This is an interesting deduction since the fossil found did not have complete hind legs. Yet based on this incomplete skeleton we get a picture of what Rodhocetus looked like. Further, despite claims of evidence of evolution from artioactyls, evolutionists admit "substantial discrepancies remain" such as cranial and dental traits, and a need to find well-preserved early specimens with intact ankles to fit the theory.[1]

It turns out that more recent finds show that Rodhocetus had substantial hind limbs, showing that it walked on land contrary to earlier reconstructions and Talk Origins' claim. This shows that the reconstruction showing a whale-like animal with small limbs was wrong, thereby creating a more substantial gap between Rodhocetus and whales.

  • Basilosaurus isis, Protocetes, Indocetus ramani and similar small-legged whales of the mid-late Eocene (45-42 Ma) -- After Rodhocetus came several whales that still had hind legs, but couldn't walk on them any more. For example, B. isis (42 Ma) had hind feet with 3 toes and a tiny remnant of the 2nd toe (the big toe is totally missing). The legs were small and must have been useless for locomotion, but were specialized for swinging forward into a locked straddle position -- probably an aid to copulation for this long-bodied, serpentine whale. B. isis may have been a "cousin" to modern whales, not directly ancestral. Another recent discovery is Protocetes, a slightly more advanced whale from the late Eocene. It was about 3m long (dolphin sized), and still had primitive dentition, nostrils at end of snout, and a large pelvis attached to the spine; limbs unknown. Finally Indocetus is known from only fragmentary remains, but these include a tibia. These late Eocene legged whales still had mesonychid-like teeth, and in fact, some of the whale fossils were first mis-identified as mesonychids when only the teeth were found.

The idea that the rear appendages are vestigial legs is falsified by the following quote from Talk Origins: "The legs were small and must have been useless for locomotion, but were specialized for swinging forward into a locked straddle position — probably an aid to copulation for this long-bodied, serpentine whale." Note that like "modern" whales this feature helps with reproduction and has nothing to do with feet. The designation of the rear appendages as vestigial legs is based purely on the assumption of evolutionary change. Besides, there are no steps between Rodhocetus and these whales, and plenty would be needed to make a case.


  • Prozeuglodon (late Eocene, 40 Ma) Another recently discovered whale, found in 1989. Had almost lost the hind legs, but not quite: still carried a pair of vestigial 6- inch hind legs on its 15-foot body.

Once again Prozeuglodon's rear appendages are called vestigial legs. The simple fact is that these structures aid in reproduction; they are not vestigial legs.

  • Eocetus, & similar "archeocete whales" of the late Eocene These more advanced whales have lost their hind legs entirely, but retain a"primitive whale" skull and teeth, with unfused nostrils. They grew to larger body size (up to 25m by the end of the Eocene), an had an elongate, streamlined body, flippers, and a cartilaginous tail fluke. The ear was modified for hearing underwater. Note that this stage of aquatic adaptation was attained about 15 million years after the first terrestrial mesonychids.

Both Eocetus and Prozeuglodon would be contemporaries. The remains of Eocetus do not seem to add up to anywhere near a complete skeleton. Hardly enough to claim as an evolutionary link.

  • Dorudon intermediusa late Eocene whale probably ancestral to modern whales.

Dorudon were probably a variety of Eocetus.


This is supposed to be evidence for evolution? One of the most critical "links" in this chain—Ambulocetus—from land animals to whales are too fragmented to be considered objective evidence. The other—Rodhocetus—has been shown to be reconstructed inaccurately in a manner that favors evolution. This is particularly important because the parts that are missing are those most critical to establishing such a link.

1. Toothed whales

  • Agorophius (late Oligocene) -- Skull partly telescoped, but cheek teeth still rooted. Intermediate in many ways between archaeocetes and later toothed whales.

There is insufficent information on Agorophius for an independent analysis, but it could be a variety of Dorudon. However, there seems to have been a gap in the Early and mid-Oligocene, since no fossils are mentioned from there, thus there is no link.

  • Prosqualodon (late Oligocene) -- Skull fully telescoped with nostrils on top (blowhole). Cheek teeth increased in number but still have old cusps. Probably ancestral to most later toothed whales (possibly excepting the sperm whales?)

Prosqualodon is clearly a variety of dolphin. Since both Prosqualodon and Agorophius are classified as late Oligocene, one cannot objectively be considered ancestral to the other.

  • Kentriodon (mid-Miocene) -- Skull telescoped, still symmetrical. Radiated in the late Miocene into the modern dolphins and small toothed whales with asymmetrical skulls.

Kentriodon is clearly a variety of dolphin. (By the way, where is the early-Miocene?)

2. Baleen (toothless) whales

  • Aetiocetus (late late Oligocene) -- The most primitive known mysticete whale and probably the stem group of all later baleen whales. Had developed mysticete-style loose jaw hinge and air sinus, but still had all its teeth.

This is a whale with characteristics of baleen whales but it has teeth. Note that the loose jaw hinge appears suddenly, with no evidence of its gradual development. What we seem to have here is a baleen whale with teeth.

This suggests an interesting possibility. The Bible shows that man lived 10 times as long before the Flood as we do today, and it is likely that this applies to animals as well. Given this, it is possible that originally baleen whales started life with teeth and lost them as they got older but the modern degenerated varieties with their shorter life spans now skip that phase of their life.

Mesocetus was a variety of baleen whale, and it did not have teeth. What we have here is teeth and then no teeth, with no evidence of a gradual loss. This is consistent with the above hypothesis.

Conclusion

As has been typical in this study, the so-called transitions consist of partial skeletons, and types for which there is little information. These are distinct kinds and variations within the created kinds of animals.

Reference: — Overselling of Whale Evolution


See Also