In discussing evolution, it is fairly common for Christians to distinguish between micro- and macro- evolution (an example of such can be seen here). Microevolution consists of changes within a species; for example, new breeds of cattle have been developed, but the new breeds are still cattle and not some other species. Macroevolution involves changes so great that that a new species emerges, a scientific theory which is rejected by many Christians that fully accept the idea of microevolution.
However, this is not a distinction that most scientists make. They tend to see all evolution as being the result of the same processes, and consider the difference between micro- and macro- evolution to be simply a difference in scale, as well as something that is a rather arbitrary difference.
As far as I know, the major problems (from a scientific standpoint) with macroevolution are that the support for it in the fossil record is very questionable, and that the actual process of one species evolving into another one has not been observed. The second problem may have just changed. According to an article in The Economist , scientists at Yale have become the first to “create a new biological species in a laboratory by encouraging the sort of ecological isolation that happens in the wild.”
The definition of species the article uses, which is what I learned in my schooling, is “a group of organisms whose members can breed with each other but not with outsiders.” I am not sure whether or not this experiment actually accomplished creating a new species by this definition.
The normal versions of Dr Turner’s phages are able to parasitise four types of bacteria. He and his team, however, found a mutant that could infect two additional species. They cultivated a population of this mutant in one of the newly available species and found that after 15 days it had adapted to its new host so well that it had lost the ability to infect other bacteria. It had thus become effectively isolated, because it could never hook up with individuals from other strains. It could therefore be considered a new species.
In any case, this is a development which merits watching. If science can produce observable examples of macroevolution, Christians may no longer be able to make the argument distinguishing between micro- and macro- evolution that is commonly used today.
[Note: My emerging impulses series is not finished and will likely return next week]
Though there would still exist the argument that scientists are “intelligent” designers and without their influence, macro-evolution couldn’t happen. But yes, that will be interesting if they can prove that macro-evolution is a possibility.
Unfortunately, by this definition any separated groups would be defined as separate species. This is not in fact the case, as animals from different regions which don’t interbreed, but which could interbreed of placed in the same environment are not generally considered different species. This article seems to be making the claim that a hairless breed of dog would be a different species than a husky, because the hairless dog could not survive arctic temperatures. If the “new bacteriophage” described is no longer able to interbreed with the “mutated bacteriophage” able to live off the “alternate bacteria”, I would be far more willing to acknowledge it as possibly being a “different type” of bacteriophage. Evolution still has problems as a theory so long as it cannot demonstrate “missing links” between species. This is a problem in both the fossil record and in the biological research (as indicated by this article).
I’m currently reading Michael Behe’s new book, The Edge of Evolution. I will write a review of it later, but I think it makes it very clear what the limits of evolution are. Whether or not evolution is within the same species or creates a new species isn’t really the big deal. It’s not a distinction worth arguing about. As with most things, the truth is more subtle. I’ll explain more when I write my review in a week or two.
I don’t
I don’t believe that this is in fact a new species, but the fact that most single celled organisms don’t reproduce by sexual means seems to be a loophole for people believing it is. By the common standard of what a species is, it doesn’t apply. I believe that in bacterium, the operative word is “strain” of bacteria instead of species.
But using their logic, ALL bacteria are a new unique species, if only differentiated by a small characteristic.