googlef87758e9b6df9bec.html A Sure Word: How Many Times are They Allowed to Redraw the Tree?

Friday, March 27, 2015

How Many Times are They Allowed to Redraw the Tree?

Have you ever read a headline that says something like, “New Fossils Forces Scientists to Redraw the Evolutionary Tree of Life”? If you are interested in evolution or creation at all, you've probably read that headline dozens of times. I know I have. Evolutionists love to talk about their much loved nested hierarchy and often trumpet it as though it's “proof” of their theory. It's funny (I mean downright hilarious) that seemingly every day, some new discovery pops up which forces them to redraw the so-called “Tree of Life.”

Just this month, National Geographic reported, “Oldest Human Fossil Found, Redrawing Family Tree.” It seems a jawbone found in Ethiopia has been dated by evolutionists as 500,000 years older than the date previously assigned to the genus Homo. A caption from the article says, “[The jawbone], spotted by Arizona State University grad student Chalachew Seyoum, puts the first members of the human genus Homo in the Afar region of Ethiopia half a million years earlier than previously thought.”

Isn't that interesting? It's especially interesting in light of the lie frequently spoken by evolutionists – Richard Dawkins in particular – which says, "Evolution could so easily be disproved if just a single fossil turned up in the wrong date order. Evolution has passed this test with flying colours." Just one fossil, huh? Flying colors, huh? Well here you go! Consider your theory disproved! Alas, they really don't mean it when they say a single, out-of-date-order fossil would disprove their theory thus I correctly identify it as a lie. When a fossil is discovered that upsets their theory of when or where some species evolved, then evolutionists simply redraw their nested hierarchy.

Now, in the fairness of full disclosure, the article goes on to say that this new find supposedly helps fill some gaps in their theory. Homo habilis had long been considered the ancestor of all Homo species. However, there was yet another jaw bone (labeled, AL 666-I), found some years earlier, that “suggests that an even more primitive "ghost lineage" of Homo must have existed.” Ah. I guess that even before this new fossil was found, the evolutionists' precious “nested hierarchy” was already in need of a tuning. It's never the neat package evolutionists tout it as being, is it?

Keep in mind, too, that this new find prompts a need to tweak the tree of life only after a parade of previous finds that were also introduced to us with similar fanfare. Here are a couple more headlines that demonstrate how scientists' previous theories about human evolution also turned out to be very wrong:

New Fossils May Redraw Human Ancestry,” NY Times, 9/8/2011
[I]f accepted, [this discovery] would radically redraw the present version of the human family tree, placing the new fossils in the center.

Fossils challenge old evolution theory,” USA Today, 8/9/2007
The discovery by Meave Leakey... shows that two species of early human ancestors lived at the same time in Kenya. That pokes holes in the chief theory of man's early evolution -- that one of those species evolved from the other.

After more than a century since Darwin said we evolved from apes, the fossil record still hasn't shown us any “clear progression” of such a thing happening. Remember too that these headlines are only dealing with alleged human ancestors – the most desirable of fossil finds. Every fossil primate skull that has ever been found for the last several decades is evaluated for a potential place in the ancestral tree of humans. Yet in spite of all their efforts, no clear lines can be drawn. Scientists only continuously rearrange broken branches that may not even belong on the same bush.

But besides human evolution, evolutionists' theories about the evolution of other species are continuously being upset by new discoveries. Here are a few more headlines for your amusement:

It doesn't sound like they're sure how anything evolved. I guess it's a good thing evolution really has no impact on science.

Are evolutionists never embarrassed by news like this? I've been told ad nauseum that the so called “tree of life” is evidence of common descent. It's one of the 29+ Evidences for Macroevolution, often cited by evolutionists while defending their theory. But how can it be evidence for anything if it has to be redrawn every other day? I understand that sometimes people exaggerate headlines in order to attract readers but when you read many of these type articles, you'll see that in most of these stories, some new find indeed does change the previous understanding of how something allegedly evolved. So how many times do they have to be wrong about the theory before people begin to question the theory itself? How many times are they allowed to redraw the tree until people begin to realize there is no tree?!


Steven J. said...

Many details of the phylogenetic tree of life are fuzzy; many branchings unresolved. For example, the order of branching among mammalian orders was long unresolvable and is still in some cases uncertain. Birds are an even more notorious example; the demands of flight so restrict the possible variations on the basic theropod body design that the relationship of bird orders (and in some cases even what orders various bird families belong in) was long uncertain, and known to be so. But it's not as though anyone has found evidence that, e.g. any bird is more closely related to bats than to other birds (or more closely related to bats than to crocodilians).

The difficulty in resolving the exact order of closely-spaced branchings on some limb is not the same as difficulty in telling whether there's a tree at all.

In the case of humans, I don't think there's ever been a real consensus on exactly which fossil groups were our direct ancestors, and which were collateral ancestors (evolutionary "great aunts" rather than "grandmothers"). There isn't even a consensus over how many different species these fossils represent -- is Kenyapithecus platyops really different enough from Australopithecus africanus to warrant placement in a different genus, or even a different species? Is Homo erectus a different "race," or an entirely different species, from H. ergaster? New fossils don't so much re-draw some canonical tree as give a bit more support to one of several contending positions. But the point remains that (as evolution implies and special creation implies should not happen) there's no place where you can draw a line dividing humans from nonhuman apes that doesn't have some intermediate fossil hominid plopped down atop it.

Henry Gee (paleontologist and evolutionary biologist) has contradicted Richard Dawkins (and J.B.S. Haldane) on the subject of out-of-place fossils; he has argued that given the incompleteness of the fossil record, the most we could infer from Haldane's hypothetical "rabbit fossil in the Precambrian" is that mammals (and amniotes, tetrapods, and vertebrates) evolved long before they appear in the fossil record. Since we expect everything to evolve before it shows up in the fossil record (albeit not half a billion years before!), this is a logical possibility, albeit wildly improbable.

Less improbable, though, is the case of fossil footprints, apparently belonging to a tetrapod similar to Acanthostega, at a time when the only skeletal fossils belong to much more primitive tetrapods like Tiktaalik. There are, after all, fossils of lobe-finned fish older yet, so whatever left the footprints didn't live millions of years before anything that might have been a close ancestor. It isn't like rabbit fossils older than any primitive mammal (or even vertebrate) fossil.

The fossil hominid jawbone, though, doesn't seem even "out of place" in that sense. It sounds intermediate between australopiths and more advanced members of Homo, and is younger than the oldest australopiths (so it has plausible ancestors). Evolution is a branching process; one possible consequence of this is primitive forms existing for a while (presumably in a different ecological niche) alongside more advanced relatives (this is why there are still apes and monkeys).

Note that the "nested hierarchy" is a consequence of but distinct from the "tree of life." This may be seen in the distinction between cladograms (which strictly deal only with what is more closely related to what, and what is more distantly related, and makes no claims about what is actually ancestral to anything else, and phylogenetic trees, which try to assign some fossil taxons to the role of ancestors rather than simply closer or more distant relatives. Fiddling with phyogenetic trees may, but probably won't, affect the nested hierarchy.

RKBentley said...

Steven J,

The fact that a clear lineage of human evolution cannot be drawn also happens to agree with the creation theory.

Humans share many features with many non-human animals. We have 4 limbs, 2 eyes, and a heart. We share more features with mammals than with birds. We have hair, give live birth, and nurse our young. Finally, we share more features with apes than with most other mammals. We have gripping hands and more similar skulls, for example. None of this is proof that humans are more “closely related” to apes than to other animals. In fact, there is no relatedness between different kinds of animals. The so-called “tree of life” is entirely a product of your theory and thus cannot be evidence for it.

If a skull is found (more often it's only a piece of a skull) that's difficult to classify as belonging to human or ape, so what of it? I can see the similarities between living apes and humans. Modern apes obviously aren't examples of transitional forms between human and non-human ancestors. If we find some extinct species of ape with skulls even more like ours, neither is that necessarily evidence of transition. Our bones are only a small part of who we are. If we took some fossil of uncertain classification and could see it living and behaving, I suspect a first grader could correctly identify it as being either ape or human.

Finally, creationists often criticize evolution as a theory on the grounds that it cannot be falsified. A rabbit in the Cambrian has been cited as a potential falsification. However, many evolutionists have disavowed that as a potential falsification. What then is left? How could your theory be falsified if not by out of place fossils? A theory so plastic as to fit any evidence is bad science.

Thank you for your comments. God bless!!


Steven J. said...

The fact that a clear lineage of human evolution cannot be drawn also happens to agree with the creation theory.

The fact that numerous plausible intermediates exist between "kinds" that are supposed to be entirely distinct is hardly a prediction one would draw from creationism. It may be consistent with creationism, but, like feathered theropods or whales with legs, it's something an evolutionist would expect and a creationist would not.

None of this is proof that humans are more “closely related” to apes than to other animals. In fact, there is no relatedness between different kinds of animals. The so-called “tree of life” is entirely a product of your theory and thus cannot be evidence for it.

Again, what we are offering as evidence is the nested hierarchy, not the tree of life inferred from it. The nested hierarchy, of course, was first pointed out by the creationist Linnaeus, and is not a product of evolutionary assumptions. Of course, mere similarity is not proof of relatedness. Their mere similarity, anatomical and genetic, even their ability to interbreed, is not proof that lions and tigers belong to a single pantherine or felid "kind." Mutatis mutandis, the same point could be made regarding any two species -- or indeed any two populations, whether or not regarded by biologists as separate species -- regarded by creationists as the same "kind."

Note, by the way, that manufactured artifacts tend not to fall into unique, consistent nested hierarchies: you may find, e.g. that a coupe and an SUV from the same year share the same CD player or GPS unit, while the same models from an earlier year lack these features, giving rise to multiple inconsistent hierarchies. Only descent with modification naturally produces nested hierarchies.

If we took some fossil of uncertain classification and could see it living and behaving, I suspect a first grader could correctly identify it as being either ape or human.

You're assuming that there is a "correct" answer. I think there is not, any more than there is a "correct" answer as to what day a child becomes an adult or an exact temperature at which a cool day becomes a warm one. The child might be confident, as various creationists are confident that, e.g. Homo erectus is clearly human, and others are confident that it is clearly a nonhuman ape.

What then is left? How could your theory be falsified if not by out of place fossils?

Have I ever explained here the Quine-Duhem thesis? Basically, a couple of philosophers of science independently pointed out that the naive, "silver bullet" model of falsification doesn't work: no single observation can falsify a hypothesis, because hypotheses can't be tested singly, and one can always save one hypothesis by sacrificing an auxiliary hypothesis.

For example, if we find a Precambrian rabbit fossil, we are not just testing the idea of common descent with modification. We are also testing the ideas that [a] the rocks in question are really Precambrian, and not much younger, [b] the fossil is found in undisturbed rock, not reworked from some much later period, [c] that it really is a rabbit, and not something grossly misidentified, and so forth and on, right down to the hypothesis [z] time travel does not exist, or if it does, no one would use it on dead rabbits. A single anomalous observation (e.g. a single Precambrian rabbit) is unlikely to overturn a theory that is otherwise well-supported by evidence. Rather, just as evolution is supported by multiple consilient lines of evidence (anatomical, genetic, fossil, biogeographical), falsification would require multiple pieces of evidence not readily dismissed by altering some single auxiliary hypothesis.