The The University of Chicago Medical Center reports this news item: A small step for lungfish, a big step for the evolution of walking, which says:
The eel-like body and scrawny “limbs” of the African lungfish would appear to make it an unlikely innovator for locomotion. But its improbable walking behavior, newly described by University of Chicago scientists, redraws the evolutionary route of life on Earth from water to land.
[T]he African lungfish can use its thin pelvic limbs to not only lift its body off the bottom surface but also propel itself forward. Both abilities were previously thought to originate in early tetrapods, the limbed original land-dwellers that appeared later than the lungfish’s ancestors.
The observation reshuffles the order of evolutionary events leading up to terrestriality, the adaptation to living on land. It also suggests that fossil tracks long believed to be the work of early tetrapods could have been produced instead by lobe-finned ancestors of the lungfish.
This has, of course, other evolutionary implications. The article says:
The discovery suggests that many of the developments necessary for the transition from water to land could have occurred long before early tetrapods, such as Tiktaalik, took their first steps on shore. Lobe-finned ancestors of the lungfishes as well as tetrapods could have evolved hindlimb propulsion and the ability to walk on the substrate at the bottom of a lake or marsh millions of years before limbs with digits and land-dwelling animals appeared.
Okay, now for the fun part. Casey Luskin, our favorite creationist, has written about this at the blog of the neo-theocrats at the Discovery Institute‘s creationist public relations and lobbying operation, the Center for Science and Culture (a/k/a the Discoveroids, a/k/a the cdesign proponentsists).
Casey’s article is Do Amphibian-Like Fish Necessarily Confirm Darwinian Evolution? Not at All. Here are some excerpts, with bold font added by us, and his links omitted. He discusses the new lungfish research and then says:
In other words, modern lungfish have certain walking abilities that were previously thought to be unique to the fish that allegedly led to tetrapods (i.e. 4-legged vertebrates) some 370-400 million years ago. … Now obviously living “walking” lungfish in 2011 aren’t in the process of evolving into tetrapods. According to neo-Darwinian theory, that transition supposedly took place about 370 million years ago. Living lungfish are supposedly descended from lungfish that have remained lungfish for hundreds of millions of years.
This sounds a lot like “Why are there still monkeys?” But let’s read on:
My point has nothing to do with the facile and incorrect “if we evolved from monkeys, why are there still monkeys?” argument. Rather, I’m rebutting those who cite specific similarities between fish and amphibians at specific periods as providing special evidence for evolution.
Actually, it has everything to do with the goofy monkey question. Casey can’t seem to come to grips with the fact that some ancient species, although long ago they may have been ancestral to a great variety of evolutionary descendants, nevertheless persist and still exist today, along with their mutated cousins. He continues:
Perhaps we shouldn’t mistake 370 my [he means "million years"] old fish with amphibian-like characteristics as necessarily providing some kind of special evidence of a transition between fish and amphibians.
No? Why not? He goes on:
Evolutionary paleontologist Neil Shubin [who discovered Tiktaalik, a fish-tetrapod transitional fossil], quoted in the article, spins it this way:
[Casey's purported quote of Shubin's "spin":] What we’re seeing in lungfish is a very nice example of how bottom-walking in fish living in water can easily come about in a very tetrapod-like pattern.
What’s wrong with that? Casey explains:
What we’re also seeing is a very nice example of how fish with tetrapod-like walking behavior need not have anything to do with a transition from fish to tetrapods.
What’s his point? Is he saying that evolution from fish to tetrapods must have been the handiwork of the magic designer? Moving along:
Few scientists were previously interested in carefully investigating the walking abilities of lungfish. Why is Shubin suddenly interested in them now? Shubin’s motivation is revealed at the end of this Yahoo.com article:
[Casey's purported quote:] These findings might also make us rethink whether recently discovered approximately 380-million-year-old tracks were in fact made by early tetrapods. They could have been created by other kinds of fish instead.
What does that mean to Casey? He tells us:
Ah, now it all makes sense. Last year on ENV we talked about how tetrapod tracks in Poland from 397 million years ago challenged Shubin’s claims (and the claims of many others) that the discovery of Tiktaalik in “rocks of just the right age” fulfilled “specific predictions” of evolutionary biology. … To be more specific, the tracks implied that tetrapods lived about 20 million years before Tiktaalik, meaning that Tiktaalik‘s placement in the fossil record was no longer “just the right age” for it to be a direct transitional form between fish and amphibians.
Okay, we get it. This is part of Casey’s war on Tiktaalik (see Discovery Institute: Tiktaalik — a “Fraudulent” Transitional Fossil). Then he drives his point home:
This is why Shubin is interested now in studying lungfish to see how they might also produce walking tracks. He’s hoping to show that perhaps these Polish tracks don’t prove tetrapods predated Tiktaalik after all. So Shubin’s motive for this research has everything to do with preserving the status of Tiktaalik — a fossil he discovered, wrote books about, and from which he won much of his fame — as a direct transitional form between fish and amphibians.
Casey’s article goes on a bit, but you get the general idea: Shubin and his Tiktaalik discovery are somehow discredited, and by implication that means the magic designer — blessed be he! — is the only answer to this otherwise incomprehensible puzzle. And although he attempted to deny it, his argument is based on the goofball question: “Why are there still walking lungfish?”
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