Creationists are always claiming that there’s no evidence for evolution — and as they do so, they are totally oblivious to the lack of evidence for their creationist mythology. One of their claims is that no one has ever seen one species evolve into another. Well, duh! — that can take thousands of generations for a large, slow-breeding species, and when changes are actually demonstrated with rapidly-breeding species like bacteria or fruit flies, they always respond that they’re still bacteria (or fruit flies, or whatever.)
It’s difficult to know what they’re thinking. Most of them probably think evolution looks something like Count Dracula turning into a bat. Others may be a bit more sophisticated and will acknowledge “micro evolution,” but they’ll claim that the fossil record isn’t sufficient to demonstrate anything else, and they waive away the evidence of common ancestry shown by DNA — even though DNA evidence good enough to force a father to pay child support.
Anyway, the next time you run across the claim that “No one has ever seen evolution in action” you can rebut it (or at least try) with this article at EurekAlert, the online news service of the American Association for the Advancement of Science (AAAS): Caught in the act: New wasp species emerging. It says, with bold font added by us for emphasis:
The concept that biodiversity feeds upon itself is an old idea, but it’s difficult to prove because it requires biologists to simultaneously catch several species red-handed just as they are becoming new species. Now biologists have proof. A new study from biologists at Rice University, the University of Notre Dame, Michigan State University, the University of Iowa and the University of Florida finds that ongoing evolutionary changes in one fruit fly species are having a domino effect on at least three species of predatory wasps. The researchers focused on the jump of a native North American fruit fly onto apple trees in the 1850s.
“Our study addresses one of the central questions in biology: How do new forms of life originate?” said evolutionary biologist Scott Egan, assistant professor of biosciences at Rice and a co-author of the new study, which is available online in the Proceedings of the National Academy of Sciences.
Here’s the published paper: Sequential divergence and the multiplicative origin of community diversity. All you can see without a subscription is the abstract, so we’ll stay with EurekAlert:
The study follows up previous research by Egan and colleagues of the fruit fly Rhagoletis pomonella, aka the “apple maggot,” which began plaguing U.S. apple growers in the 1850s. That work showed that changes in feeding and mating habits of Rhagoletis are driving it to become two different species.
Yeah, but they’re still fruit flies. [*End creationism mode*] Anyway, let’s read on:
“Our new work takes a close look at the evolutionary process termed ‘sequential speciation,'” Egan said. “Sequential speciation identifies the fact that adaptation and speciation of one species is not an isolated process. The appearance of a new species creates new niche opportunities that can be exploited by other species, and that opportunity can promote the origin of other new species.”
Rhagoletis is in the act of evolving into two species. The change is driven by differently timed fruiting cycles between apple trees, which some Rhagoletis prefer, and the North American hawthorn, the native fruit where Rhagoletis have traditionally laid their eggs. In extending their work on Rhagoletis speciation, the researchers focused on three species of wasps that are known parasites for Rhagoletis.
Egad — there’s no end to it! We continue:
Wasps were collected from a number of different fly host plant environments in the wild. Analyses showed that all three wasp species were also in the process of diverging into two distinct species, both genetically and with respect to host-associated physiology and behavior.
These evolutionary changes, which are known as “sequential” or “cascading” events, may provide additional information to help biologists explain why certain organisms like plants and insects are more diverse and species-rich than other groups are.
One more excerpt:
“Why are there so many insect species?” Smith asked. “Speciation cascades provide one explanation for how a lot of species might be generated in a relatively short period of time.”
Alas, this won’t persuade a creationist that he’s wrong. Nothing will, because their brains are programmed to reject information from the real world. But if it makes you happy to debate with such people, now you have some additional ammunition.
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