Elephants (Talk.Origins)

Response Article

This article (Elephants (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 Elephants

CreationWiki response: (Talk.Origins quotes in blue)

• Minchenella or a similar condylarth (late Paleocene) -- Known only from lower jaws. Has a distinctive broadened shelf on the third molar. The most plausible ancestor of the embrithopods & anthracobunids.

Note that Minchenella is known only from its lower jaw. So we know nothing about its body shape, or much else for that matter. The reference to it as the "most plausible ancestor" shows that they do not have real evidence here. So this line starts out with a highly questionable proposed ancestor.

• Phenacolophus (late late Paleocene or early Eocene) -- An early embrithopod (very early, slightly elephant-like condylarths), thought to be the stem-group of all elephants.

Both Phenacolophus and its questionable alleged ancestor Minchenella are both classified as late Paleocene; though some Phenacolophus are classified as early Eocene; so they would be contemporaries, making the already questionable lineage even more suspect. Beyond this there no information available on Phenacolophus, not even a decent description.

• Pilgrimella (early Eocene) -- An anthracobunid (early proto-elephant condylarth), with massive molar cusps aligned in two transverse ridges.

With all the talk of teeth, it makes one wonder, do they have any thing besides a jaw?

• Unnamed species of proto-elephant (early Eocene) -- Discovered recently in Algeria. Had slightly enlarged upper incisors (the beginnings of tusks), and various tooth reductions. Still had "normal" molars instead of the strange multi-layered molars of modern elephants. Had the high forehead and pneumatized skull bones of later elephants, and was clearly a heavy-boned, slow animal. Only one meter tall.

There is no mention of any post cranial bones. The reference to its being heavy-boned may suggest more but it is too vague. Besides, this so called proto-elephant is classified as early Eocene, as is its alleged ancestor, meaning that at best the order is arbitrary. The result is that the order presented here is based only on the assumption of evolution, a fact that is demonstrated by the use of the term "proto-elephant".

Moeritherium, Numidotherium, Barytherium (phttp://www.ebeltz.net/firstfam/geocolum.html early-mid Eocene]) -- A group of three similar very early elephants. It is unclear which of the three came first. Pig-sized with stout legs, broad spreading feet and flat hooves. Elephantish face with the eye set far forward & a very deep jaw. Second incisors enlarged into short tusks, in upper and lower jaws; little first incisors still present; loss of some teeth. No trunk.

First of all Moeritherium, Numidotherium, and Barytherium would all be contemporaries with the two previous types; thus the order of all five is based largely on the assumption of evolution, though placing these three as the last of the five would be supported by the clasification of some as mid-Eocene.

Moeritherium

• Not only are there at least two quite different reconstructions of Moeritherium, there seems no evidence of a relationship between Moeritherium and elephant particularly in light of Barytherium.
• Reference: The Elephant Sanctuary, Hohenwald, Tennessee
• Reference: Discovery Channel :: Walking With Prehistoric Beasts
• Reference: ABC - Science - Beasts - Moeritherium Factfile

Numidotherium

• No information available on this type.

Barytherium

• Despite Talk Origins' claim to the contrary Barytherium did have a trunk.

Barytherium is clearly just a short-tusked variety of elephant. This means that we have an elephant in the "early-mid Eocene". This also means that Paleomastodon and Phiomia cannot be transitional between elephant and any thing else. It also eliminates Moeritherium and Numidotherium as elephant ancestors.

Paleomastodon, Phiomia (early Oligocene) -- The first "mastodonts", a medium-sized animal with a trunk, long lower jaws, and short upper and lower tusks. Lost first incisors and canines. Molars still have heavy rounded cusps, with enamel bands becoming irregular. Phiomia was up to eight feet tall.

Here it just jumps to the early Oligocene, with no reference to the late Eocene.

Curiously Paleomastodon is depicted with less of a trunk than Barytherium. Given the fact that an elephant's trunk is soft tissue that unusually is not preserved, it is likely that these reconstructions have been influenced more by evolutionary assumptions than reality. The fact is that Barytherium eliminates Paleomastodon as being transitional between elephant and any ancestor. Paleomastodon was simply a variety of elephant.

Phiomia is probably an extinct variety of elephant.

GAP: Here's that Oligocene gap again. No elephant fossils at all for several million years.

Simply put, they have no elephant fossils that they can label as mid-late Oligocene. This also means that they have to assume that the links exist. However the presence of Barytherium (definitely a true elephant) before this makes claiming a transition erroneous.

Gomphotherium (early Miocene) -- Basically a large edition of Phiomia, with tooth enamel bands becoming very irregular. Two long rows cusps on teeth became cross- crests when worn down. Gave rise to several families of elephant relatives that spread all over the world. From here on the elephant lineages are known to the species level.

Gomphotherium was clearly a variety of elephant and it supports the view that Phiomia was a variety of elephant.

The mastodon lineage split off here, becoming more adapted to a forest browser niche, and going through Miomastodon (Miocene) and Pliomastodon (Pliocene), to Mastodon (or "Mammut", Pleistocene).

Miomastodon, Pliomastodon and Mastodon are all varieties of elephant.

Meanwhile, the elephant lineage became still larger, adapting to a savannah/steppe grazer niche: Stegotetrabelodon (late Miocene) -- One of the first of the "true" elephants, but still had two long rows of cross-crests, functional premolars, and lower tusks. Other early Miocene genera show compression of the molar cusps into plates (a modern feature ), with exactly as many plates as there were cusps. Molars start erupting from front to back, actually moving forward in the jaw throughout life. Primelephas (latest Miocene) -- Short lower jaw makes it look like an elephant now. Reduction & loss of premolars. Very numerous plates on the molars, now; we're now at the modern elephants' bizarre system of one enormous multi-layered molar being functional at a time, moving forward in the jaw. Primelephas gomphotheroides (mid-Pliocene) -- A later species that split into three lineages, Loxodonta, Elephas, and

Stegotetrabelodon, Primelephas and Primelephas gomphotheroides were simply a variety of elephant. What does Talk Origins mean by "first of the "true" elephants"? Barytherium was clearly an elephant, as were Mastodons.

Mammuthus: 1. Loxodonta adaurora (5 Ma). Gave rise to the modern African elephant Loxodonta africana about 3.5 Ma. 2. Elephas ekorensis (5 Ma), an early Asian elephant with rather primitive molars, clearly derived directly from P. gomphotheroides.to: 3. Mammuthus meridionalis, clearly derived from P. gomphotheroides. Spread around the northern hemisphere.

• Loxodonta is just the genus of African elephant
• Elephas is the genus of the Asian and Indian Elephants
• Mammuthus is simply a variety of elephant.

The Pleistocene record for elephants is very good. In general,after the earliest forms of the three modern genera appeared, they show very smooth, continuous evolution with almost half of the speciation events preserved in fossils. For instance, Carroll (1988) says: "Within the genus Elephas, species demonstrate continuous change over a period of 4.5 million years. ...the elephants provide excellent evidence of significant morphological change within species, through species within genera, and through genera within a family...."

Clearly, in the case of elephants, the original kind would be about equivalent to the family.

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This actually depicts at least two distinct kinds of animals: elephant and Moeritherium. Possibly more since there was insufficient information on other non-elephant types.

See Also

• Transitional forms