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Media Overblows Claims of "Human Evolution": Examining the Newest "Missing Link"

Recently I highlighted how the coverage of Tiktaalik revealed the fascinating phenomenon that only after discovering a new "missing link" will evolutionists acknowledge the previously paltry state of fossil evidence for evolution. This behavior is again witnessed in coverage of the discovery of Australopithecus anamensis fossils in Ethiopia. The media has also exaggerated and overblown claims that this evidence supports "human evolution."

The latest "missing link" is actually comprised of a few tooth and bone fragments of Au. anamensis, an ape-like species that lived a little over 4 million years ago. Incredibly, claims of "intermediacy" are based upon 2-3 fragmented canines of "intermediate" size and shape. This has now led to grand claims in the media of finding a "missing link." Because some bone fragments from Ardipithecus ramidus and Australopithecus afarensis were also found in the area, MSNBC highlighted these finds on a front-page article calling this "the most complete chain of human evolution so far." Media coverage of this find thus follows an identical pattern to that of Tiktaalik: incredibly overblown claims of a "transitional fossil" follow stark admissions of how previously bleak the evidence was for evolution. Moreover, claims that this find enlightens "human evolution" are misleading, as these fossils come from ape-like species that long-predate the appearance of our genus Homo, and thought to be far removed from the origin of "humans."

Evolution was "obscure" then and it's obscure now:

As noted, evolutionists only admit how weak the evidence was for evolution after they have some new allegedly "transitional" fossil in their hands. Compare how identical diction was used in Nature to concede the previously "obscure" evidence for tetrapod, and then now australopithecine evolution after recent fossil discoveries were made:

Tiktaalik: "[T]he origin of major tetrapod features has remained obscure for lack of fossils that document the sequence of evolutionary changes" (Daeschler et al., "A Devonian tetrapod-like fish and the evolution of the tetrapod body plan," Nature, Vol 440:757-763 (April 6, 2006); emphasis added)

Australopithecus: "Until recently, the origins of Australopithecus were obscured by a sparse fossil record." (White et al., "Asa Issie, Aramis and the origin of Australopithecus," Nature, Vol 440:883-889 (April 13, 2006); emphasis added)

Apparently the MSNBC article even felt comfortable enough to admit that we never previously had a continuous sequence of fossils documenting "human evolution" in one place:

"Until now, what scientists had were snapshots of human evolution scattered around the world. Finding everything all in one general area makes those snapshots more of a mini home movie of evolution."

(Fossil discovery fills gap in human evolution, by Seth Borenstein, Associated Press, 4/12/06)

Of course the lack of a "mini home movie" never bothered evolutionists before: critics have always been told not to request continuous fossil sequences exhibiting evolution because species can migrate, and often the evolution takes place in small, isolated populations that don't get preserved as fossils. As Niles Eldredge once said, evolution seems to always be "going on somewhere else." We wouldn't expect to find a continuous sequence of fossil species evolving all in on place; at least, that's what we were told before they found these fossil specimens.

If the origin of Australopithecus was previously "obscured by a sparse fossil record," then one would presume that now we have the answers. Turns out the evidence still remains very "obscure."

What did they really find?
What has really been found has been said to be nothing "new," just an interesting new "location":

"The species anamensis is not new, but its location is what helps explain the shift from one early phase of human-like development to the next, scientists say." (MSNBC article, emphasis added)

According to the National Geographic news article, the find consisted "mainly of jawbone fragments, upper and lower teeth, and a thigh bone"--not an impressive array of bones. The Nature article notes that the teeth they found are nothing new because they "definitively place the Asa Issie sample within expected ranges of Au. anamensis variation." (Nature 440:883-889.) So in other words, they found a few tooth and bone fragments representative of a pre-existing species--nothing truly new!

Missing Link or Missing Teeth?
Incredibly, the entire claim that this species represents a "transitional form" is due to a couple teeth which have intermediate size:

"'This appears to be the link between Australopithecus and Ardipithecus as two different species,' White said. The major noticeable difference between the phases of man can be seen in Australopithecus' bigger chewing teeth to eat harder food, he said." (MSNBC article)

If this incredible new evidence isn't about to make you a convert, then consider how impressive the media has stated this evidence is:

"The latest fossil unearthed from a human ancestral hot spot in Africa allows scientists to link together the most complete chain of human evolution so far." (MSNBC article)

But here's where the evolutionists make their public relations error: if this is "the most complete chain," then their best "chain" has a lot of missing "links." These bone fragments purportedly tell us how the ape-like genus Australopithecus evolved from the ape-like genus Ardipithecus. Let's look at 3 graphics to asses just how impressive this evidence actually is:

1. Photo of the bone and tooth fragments from which came this "missing link":


(from MSNBC article)

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2. Figure 3 from White et al.: Figures 3a and 3b show the glued-together teeth and/or fragments of teeth which form the entire basis for calling this find "intermediate." This is the whole basis for the authors' and the media's claims that this is a "missing link." In 3b there are 2 canines, which form the basis for the "intermediate" claims. In Figures 3d - 3g, the new "intermediate" data is represented in the ASI 2&5 column, which consists of a meager 2 - 3 tooth specimens (seen in the 2 - 3 small square data-points in that column).


(Adapted by permission from Macmillan Publishers Ltd: Nature, T. D. White et. al. "Asa Issie, Aramis and the origin of Australopithecus," 440:886 (2006).)

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3. Figure 4 from White at al.: Figure 4a shows precisely what was transitional in this Au. anamensis species: its "Masticatory robusticity" (in other words, its ability to chew harder stuff). Seriously, I am not kidding: this forms the basis for the authors' and the media's claims that this is a "missing link." The evidence for evolution is so abundant [note: sarcasm] that when comparing evolutionary models in Figures 4b and 4c, they explain that "Neither hypothesis can be falsified with available sample densities" because the fossil record is so poor. That's fine: but this should help us to understand the state of the evidence if this is "the most complete chain of human evolution so far."


(Adapted by permission from Macmillan Publishers Ltd: Nature, T. D. White et. al., "Asa Issie, Aramis and the origin of Australopithecus," 440:886 (2006).)

As a Neo-Darwinism skeptic, all I ask is please don't throw me in that briar patch of "intermediate-sized/shaped" (and sometimes glued-together) tooth fragments of previously known hominid species!

Putting the Evidence Into Perspective
Australopithecus was an ape-like genus that is said to have lived from about 1-4 million years ago, and some of its members are said to have evolved into our genus, Homo, around 2 Ma. But this locale doesn't implicate fossils of Homo, nor does it show anything but very early Australopithecus fragments and some Ardipithecus fragments. This find doesn't document anything about the evolution of our actual genus Homo. So why do these media articles misleadingly state this evidence documents "human evolution?"

And what about those "links" farther down the "chain" showing how Australopithecus evolved into Homo? Consider what some authors wrote in a study that wasn't highlighted on the front page of MSNBC:

"The anatomy of the earliest H. sapiens [here meaning Homo erectus & Homo ergaster] sample indicates significant modifications of the ancestral genome and is not simply an extension of evolutionary trends in an earlier australopithecine lineage throughout the Pliocene. In fact, its combination of features never appears earlier..."

(Hawks, J., Hunley, K., Sang-Hee, L., Wolpoff, M., "Population Bottlenecks and Pleistocene Evolution," Journal of Molecular Biology and Evolution, 17(1):2-22 (January, 2000))

MSNBC never highlighted this article on their front page because these authors said the origin of Homo required "a genetic revolution" where "no australopithecine species is obviously transitional." (Sorry, but Au. habilis doesn't cut it.) One commentator even called the state of evidence as showing a "big bang theory" of human evolution (see "New study suggests big bang theory of human evolution"). Perhaps this is because "[t]he first members of early Homo sapiens are really quite distinct from their australopithecine predecessors and contemporaries":


(Left: early member of the genus Homo. Right: one of our alleged australopithecine ancestors. Here the missingness of the link becomes stark. Quote and graphic from "New study suggests big bang theory of human evolution.")

But the evidence presently on MSNBC doesn't even deal with how Homo evolved from Australopithecus. If this is the most complete "chain," then indeed, we're dealing with very fragmentary evidence for "human evolution." More poignantly, this article is wrong to imply this evidence says anything about how ape-like australopithecines evolved into our genus, Homo. Even lead author of the Nature article, Timothy D. White, misleadingly stated in the MSNBC article that this evidence documents "phases of man." That's not true: if anything, these bone fragments provide miniscule suggestions of early phases of very ape-like hominids that predate Homo by 2 m.y. and "man" (Homo sapiens sapiens) by over 3 m.y. This evidence may help plug a miniscule gap in australopithecine evolution (recall, no new species was found, and all they found that was interesting were a couple canines of intermediate size), but contrary to what the MSNBC article says, nothing documents "human evolution" or "phases of man."

The More Things Evolve, The More Things Undergo Stasis
Recent news articles are engaging in emotionalism to blow up these finds of Au. anamensis fossils into something they aren't: a "missing link" that documents "human evolution." It seems that little has changed since 1981 when Constance Holden wrote in Science:

"The field of paleoanthropology naturally excites interest because of our own interest in origins. And, because conclusions of emotional significance to many must be drawn from extremely paltry evidence, it is often difficult to separate the personal from the scientific disputes raging in the field." ("The Politics of Paleoanthropology," Science, p.737 (August 14, 1981).)

If the present evidence for australopithecine evolution before this find was "obscure," perhaps it's safe to say they're still very much in the dark, and that very little has changed in the past 25 years.