It may be said that natural selection is daily and hourly scrutinizing, throughout the world, every variation, even the slightest; rejecting that which is bad, preserving and adding up all that is good; silently and insensibly working, wherever and whenever opportunity offers, at the improvement of each organic being in relation to its organic and inorganic conditions of life.
However, it hasn’t turned out that way. Nature seems not to like such orderly schedules much. Evolutionary biologist Donald Prothero admits:
In four of the biggest climatic-vegetational events of the last 50 million years, the mammals and birds show no noticeable change in response to changing climates. No matter how many presentations I give where I show these data, no one (including myself) has a good explanation yet for such widespread stasis despite the obvious selective pressures of changing climate.
The first major discovery was that stasis was much more prevalent in the fossil record than had been previously supposed. Many paleontologists came forward and pointed out that the geological literature was one vast monument to stasis, with relatively few cases where anyone had observed gradual evolution.
Similarly, biologist and paleontologist Niles Eldredge, best known for his theory of punctuated equilibrium (“sudden appearance” of phyla, classes, and orders, followed by long periods of stasis) has noted:
As a PhD candidate, I set out to collect trilobite fossils from all over the Midwest. And I started to realize that the fossils I was collecting — whatever point in time I was in — all looked the same. I found no evidence of change. At first I put that down to my inexperience…”I’m not good enough to see the obvious changes that are here.”
An evolutionary biologist at the University of Oslo, Kjetil Lysne Voje, offers an explanation for stasis:
The most wide-spread explanation is stabilising selection. It suggests that the advantage for a species which is already well adapted to its environment will be to avoid changing much. It is a type of natural selection that favours the average individuals in a population because changes are disadvantageous. Changes are a drawback and stabilising selection will discard deviations from the well-functioning norm.
“Stabilising selection is a very good explanation for stasis, as it helps a species remain unchanged. But it has some problems, as it is hard to conceive of an optimal form that would not change in the course of millions of years,” says Voje.
Unfortunately, Voje has, in his last sentence, blown up his own thesis.
Species often explode suddenly into life, as in the Cambrian explosion, which even Darwin found to be a problem for natural selection. (See the new short video from Discovery Institute, The Information Enigma.) Some of them do not persist beyond the age to which they are adapted. That does not require an explanation.
But others just settle down to long eons where they don’t change much, no matter what the environment. And “stabilizing selection” does not account for that. The cockroach, for example, is still around and still easily identifiable after perhaps 350 million years. The 350-million-year-old coelacanth fish and the 300-million-year-old horsetail grass survive largely unchanged.
When the coelacanth, supposed extinct for 70 million years, turned up in the Indian Ocean in 1938, it disappointed biologists who hoped for a living proof of Darwinism.1 It is a living proof of non-Darwinism.
Similarly, a recently discovered 425-million-year-old crustacean showed no significant changes in internal body parts, compared to present-day specimens. One researcher called it “a demonstration of unbelievable stability.” But the stability is only unbelievable if we start with Darwin’s assumption that “natural selection is daily and hourly scrutinizing, throughout the world, every variation, even the slightest.” Apparently not.
Similarly, comb jellies, far more complex than sponges, evolved before sponges, more than 550 million years ago. As one scientist put it, “It’s just wild to imagine” that comb jellies evolved before sponges. Why? What are the assumptions here? Stasis followed by eventual extinction may well prove to be even more common in the history of life than we have so far seen.
Continue reading the article at Evolution News and Views.