Field of Science

Dog speciation

Great post on skepticblog by Daniel Loxton revealing (I think that's the right word) that AiG-type creationists actually think Darwin was right.
creationist leaders share Darwin’s belief that species routinely change (and even originate) through mutation and natural selection.
Indeed, according to Answers In Genesis’ (AiG) current web feature “Top 10 Myths About Creation,” it’s a straw-man to suppose creationists think otherwise:
A popular caricature of creationists is that we teach the fixity of species (i.e., species don’t change). And since species obviously do change, evolutionists enjoy setting up this straw-man argument to win a debate that was never really there in the first place.
Weird, right? But wonderful, that they believe in evolution after all. Or not?
Creationists have long been amazed by the diversity within each created kind (or baramin, roughly on the family level). We know that species do change—but only within the original kinds God created roughly 6,000 years ago.

Species changing via natural selection and mutations is perfectly in accord with what the Bible teaches. Such changes are not evolution—they remind us that God put enough information in the genome of each original kind to live and flourish in a cursed world.
Oh, what scientists call evolution they do not. But they do allow (again, I think that's the right word) changes within families - which would then allow for speciation. But not change at taxonomic levels higher than that.

My reply to John Heininger in the comments of skepticblog:

John, at what hierarchical level of taxonomy do you require observed bifurcation before you will accept macroevolution? Bacteria are a domain, amphibians (tadpoles) are a class, finches are a family, pigeons are a family, monkeys are two pavorders, humans are a species, fruit flies are two families, and viruses are completely off the charts.

The point is that what you are asking for as the only evidence you'll accept for macroevolution is something that we know takes many times the life-span of humans. Speciation, which has arguably been directly observed (e.g. in E. coli, Podarcis lizards, certain plants, finches), is macroevolution by everyone else's definition, and yet the examples you apparently crave have raised the bar intolerably.


Same species, really?

Suppose you were an alien visitor to Earth, and you have to classify species by the same criteria that biologists today use. Surely you would say that ruby throated tigers and lions are different species, right? Sure, they can actually interbreed, and yet it is common sense that they are different, based on their morphology, behavior, etc. Next look at dogs. If at first you only see a great dane and a chihuahua, SURELY you would say they are at least as different from each other as lion and tiger are from each other. My point is that the two dogs, though both characterized as dogs (which is normally considered a species), are different enough to be labeled as two different species (in fact, I challenge the common notion that they can interbreed, which if true would rule them different species), and we know that those two dogs share a common ancestor.


More chihuahua.

4 comments:

  1. It's always really annoying to me when laypeople (such as myself) get all obsessed over taxonomy. I grant that a logical and as-comprehensive-as-possible system of taxonomy is very useful in many fields of biology (and maybe some others, I'm no expert). But obviously there is no real world referent to taxonomy; it is just an arbitrary system overlaid on the idiosyncratic relationships between different organisms in order to help certain types of scientists make sense of it. From a lay perspective, it doesn't really matter at all.

    By the same token, I have very mixed feelings to the evolutionist response in the following common exchange:

    Creationist: So you are saying we evolved from monkeys?

    Evolutionist: *sigh* No no, I am saying we have a COMMON ANCESTOR with monkeys.

    On one hand, it's important to point out that nobody is saying we evolved from modern monkeys. On the other hand, whether that common ancestor ought to be called a monkey or an ape or something completely different is irrelevant to the discussion, and probably not particularly interesting to most of us. (I watched a YouTube video that made a case that the only consistent taxonomy necessitated us calling the whole lot of them "monkeys"... probably an interesting and provocative point for an evo biologist, but for me it was the teacher on Peanuts :D )

    So anyway, yeah, Creationists trying to say that a baramin is defined as being the same as a family... WTF...

    On a side note, I just heard about baraminology within the past year, and I laughed and laughed and laughed....

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  2. Sure, the primate ancestor probably looked somewhat like a monkey, but the point is that many laymen think that we actually evolved from the extant monkeys. "So why are there still monkeys?"

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  3. So, being an evo biologist, maybe you can illuminate me on this one... It doesn't seem to me like the persistence of an ancestor species would be any sort of deal-breaker, i.e. even if we did evolve from extant monkeys, so what? We know it is not the case from the fossil record and from genetic analysis, but if we didn't know those things, wouldn't it be conceivable for the ancestors of homo sapiens to have been derived by peripatric speciation from the same species as modern chimpanzees?

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  4. Whoa! Peripatric speciation. You don't see that term used often.

    Yes, quite conceivable, I would say. Why not? We could have branched off the main stem of the big monkey lineage, and the monkeys staying largely the same for the usual reasons for stasis (link is to a post I wrote on stasis exactly one year ago today).

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