Loading

Nasal Drift in Early Whales / Review Of A Whale of a Tale? (Ambulocetus)

Cetacean Evolution (Whales, Dolphins, Porpoises)

Evidence Of Common Ancestry of Cetaceans and Certain Species of Land Mammals

by Edward T. Babinski

(Reviews of several creationist articles that deny such evidence exists.)


REVIEW OF A Whale of a Tale? (Ambulocetus) Don BattenThe author states, ". ..there is no evidence [in Ambulocetus] of the development of the horizontal tail flukes so characteristic of whales." Evolutionists don't expect Ambulocetus to have had tail flukes: "Unlike modern cetaceans, Ambulocetus had a long tail and thus probably lacked a tail fluke."
(Thewissen, Science, January 1994, p. 211)
See this link.


(Neither does the cartilage which constitutes the tail flukes of whales preserve as well as bone does.)
Since we are talking about the tail of Ambulocetus let me add a "review within a review" of another creationist article whose author stated, "The tail movements [of the earliest whales] would begin to crush its reproductive apparatus against its pelvis. This would have a tendency to lower the animal's sexual urges somewhat and it would soon lose interest in reproduction -- not a very positive evolutionary step. Taken to extremes, this new tail movement would simply crush the whole pelvis. The selective pressures of the environment, or natural selection, would work against any such change of tail on a land-dwelling mammal."


This "tail swinging" argument is from 1984 when Gish used to show his slides of a cow evolving into a whale, calling it an "udder failure" (Gish, 1985). But even back in 1984 biologists knew that " . . . the giant river otter Pteronura) of South America possesses a horizontally widened tail that produces thrust, even though the caudal vertebrae are of a typical terrestrial form (Fish, 1998)." And the river otter hasn't become extinct yet. "Furthermore, the swimming method of these otters (dorso-ventral undulation of the vertebral column) makes a very good analogy for the swimming method of Ambulocetus. (Thewissen, 1998)."


"It is known from the fossil record that in Ambulocetus, the toes are elongated and the femur is short. The other skeletal elements are no different than other land mammals (Thewissen, et al, 1994) . . . .In the earliest known protocetid, Rodhocetus, there are . . . a further reduction of the femoral length, the rearward migration of the nares (nasal bones), to above the canine teeth (this is true of Rodhocetus, but in Ambulocetus, the narial region is still unknown), the sacral vertebrae are unfused, although they still articulate fully with the pelvis, a shortening of the cervical (neck vertebrae), and probably the most important, are the changes in the caudal (tail) vertebrae. In Rodhocetus the tail vertebrae are relatively shorter, thicker, and more massive than those of land mammals, allowing for better attachment for the muscles involved in powering the, very likely, recently evolved flukes (Gingerich, et al, 1994)."


REVIEW OF A Whale of a Tale? (Ambulocetus) Don Batten(Continued) The author states, "There is no evidence of. . . the unique hearing system of whales (i.e. with no opening to the exterior)." But "Ambulocetus had whalelike skull characteristics that are found in the Archaeocetes ["early whales"], including an ectotympanic with a large sygmoid process, a reduced zygomatic arch, a wide supraorbital process and a narrow muzzle. While these characteristics may also be present in the terrestrial Mesonychids, Ambulocetus also possessed the small protocones and large accessory cusps which distinguish the whales from the Mesochynids."
See this link.


(Apparently the author is unaware of the fossil data and research concerning the earbones of Pakicetus and other early whales.) The author states, "There is no evidence of. . . the blow-hole." No evolutionist expects Ambulocetus to have had a blowhole. The earliest known whale, Pakicetus, had nostrils near the tip of its snout. Ambulocetus we don't know about, but wouldn't expect it to have had a blowhole because even Rodhocetus (more adapted for the water) had no blowhole, though it did have nostrils that were moved back from the front to a place above the canine teeth. Later on we see that Basilosaurus's nostrils were in the middle of its snout, still only halfway toward its head. Even Eocetus and similar "archeocete whales" of the late Eocene that have lost their hind legs entirely, still retained a "primitive" whale's skull and teeth, and unfused nostrils.
Here and here.


Nasal Drift

LAND TO SEA: NASAL DRIFT IN WHALES

Image Source: Home Archive; based on an Image in National Geographic, November 2001, "The Evolution of Whales", page 75

"Modern day toothed whales including porpoises and dolphins have one blowhole while baleen whales have two."


REVIEW: A Whale of a Tale? (Ambulocetus) Don Batten
(Continued) The author states, "The robustness of the femur, and presence of hooves confirm the creature as a land animal." "Land animal?" Look at the pic and consider the size of the creature in relation to the length of its arms and legs, especially its shortened forearms, and the way its femur is relatively short compared with that of land animals. And notice how long its fingers and toes were! Seems more adapted to swimming than walking/running on land, though it probably spent time on land. Even crocodiles with their short arms and legs spend time on land, but I wouldn't call them strictly "land animals." As for Ambulocetus's "hooves," it is true that it had long fingers that ended with tiny hooves on each one but that confirms yet another link between the earliest whale-like mammals and the Family Mesonychidae which was the same Family that Pakicetus belonged to.


Make a shorter URL to this article. Highlight link and "Copy To Clipboard"

No comments:

Post a Comment