240 Evolution? The Fossils Say YES!
it still retains a lot of fishy characteristics, such as the tail fin, the bones covering the gill slits
(opercular bones), and especially the series of canals on the face (lateral line canals) for sens-
ing movement and electrical currents under water. This lateral line system is a feature found
in most sharks, teleosts, and many other aquatic animals. Once again, we have a classic
fishibian: limbs and spine like a tetrapod, but tail fin, gills, and lateral line canals like a fish.
Creationists, of course, cannot admit that this animal is a true transitional form, so
they stoop to all sorts of dishonest arguments to deny its fishibian features. Gish (1978; he
learned nothing new in his 1995 edition) is typical of the bunch. Ichthyostega had limbs and
feet, so it must be an amphibian, and then Gish goes on to quote outdated ideas about it.
Gish (1978, 1995) keeps claiming that there are no fossils that document the transition from
fins to feet, but now with Panderichthys, Tiktaalik, and Acanthostega, we do have fossils that
had seven or eight fingers or toes on their limbs, which are clearly still used as fins, not
as hands or feet. He never mentions the gill covers, the lateral line system, or the tail fin,
aquatic features of Ichthyostega that are not found in most tetrapods. This is a clear case of
selective citation of evidence and deliberately misleading argumentation. Either Gish can’t
read the description of the fossil well enough to understand that it has features of both fish
and tetrapods, or he is deliberately trying to fool the reader by denying the obvious and
well-documented fishlike features of these fossils. Either way, it is extremely poor science
and very dishonest.
The creationist arguments usually stop right there: mislead the reader into thinking that
Ichthyostega is “just” an amphibian and don’t mention all its fishy features, and then move
on to another topic. Well, that argument is finished for good. The amazing array of new tran-
sitional fossils (fig. 10.6) documents the transition in such detail that the creationists can’t
dodge behind trying to just discredit Ichthyostega anymore. The discovery of Acanthostega
and Tiktaalik vastly improves our knowledge of the origin of tetrapods and shows that the
earliest tetrapods used their legs not for walking on land but primarily for walking under the
water! All of the old arguments about tetrapods needing robust limbs to crawl out to another
pool or chase new prey are completely obsolete now that we know that walking underwater
was the primary function of the limbs of Ichthyostega and Acanthostega. And all of their fishy
features, such as the ear region, lateral line canals, and tail fins now make sense if we think
of them as comparable to modern newts and salamanders that only rarely crawl out on land.
As we saw from all the walking teleost fish, crawling out of the water is not such a feat after
all, especially if you spend most of your time in the water. For that matter, most amphibians
spend most if not all their time in the water, so they haven’t made as great an evolutionary
leap as the old dogmas once suggested.
How do the ID creationists deal with this extraordinary evidence? They cloud the
issue by denying these fossils exist, or by distortion and misstatements. Davis and Kenyon
(2004:103, figs. 4–8) show a 55-year-old sketch of Ichthyostega and Eusthenopteron but make
no mention of all the other transitional fossils that were well documented before their book
was published in 2004. They show (figs. 4–9, p. 104) the fin and limb bones of each of these
creatures but ignore all the beautiful transitional fossils that have been documented in the
past 50 years. They make a big deal about how dramatic this transition was, yet falsely claim
that “no such transitional species have been recovered.” Thanks to Panderichthys and Acan-
thostega, and now Tiktaalik, that falsehood can be safely laid to rest—but I have no expecta-
tion that creationist books will ever acknowledge the existence of these fossils. I’m sure they
will simply replay their discredited and outdated arguments.