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Author Topic:   Creationists Cannot Define "Kind".
lpetrich
Inactive Member


Message 40 of 69 (37422)
04-20-2003 11:18 PM


History of Taxonomy?
I wonder if anyone has put together a history of taxonomic schemes; I could not find very much on the Internet.
Here was Aristotle's classification of the animal kingdom:
Blooded animals:
- Viviparous quadrupeds (mammals)
- Birds
- Oviparous quadrupeds (reptiles, amphibians)
- Fish
- Whales and dolphins
Bloodless animals:
- Cephalopods
- Crustaceans
- Insects (true insects, arachnids, myriapods)
- Shelled animals
- Plant-animals (zoophytes) (sea anemones, etc.)
Linnaeus's classification of the animal kingdom was similar in spirit, though explicitly hierarchical and more detailed.
His classification of the plant kingdom, however, was much more artificial -- he classified flowering plants by stamen count. It was convenient for identification if not much else, and later biologists worked out a proper "Linnean" classification of plants.
Linnaeus's system we remember on account of its being biologically "reasonable"; there were several others proposed in past centuries.
I recall from somewhere that 18th cy. naturalist Buffon proposed classifying by usefulness to humanity, with the cow coming the closest to our species.
And in the early 19th cy. a certain Swainson proposed a "quinary" system, which was a hierarchical system that used groups of 5 arranged in circles. This seems almost impossibly forced, and it was strongly criticized by Swainson's contemporaries.
[This message has been edited by lpetrich, 04-20-2003]

  
lpetrich
Inactive Member


Message 41 of 69 (37426)
04-20-2003 11:52 PM


That digression aside, the main criterion I've seen from creationists is interfertility. A set of all organisms that are interfertile with each other form a "created kind" or a "baramin". However, there are ambiguous cases, such as ring species, where neighboring populations are interfertile, except for one spot. This has a natural explanation in evolution: an ancestral population spread in a ring shape until the two ends ran into each other.
A similar phenomenon happens in domestic dogs, where the largest and the smallest breeds cannot crossbreed, but are nevertheless connected by a large number of intermediate-sized breeds.
Pre-Darwinian biologists tended to believe that each individual species was a separate creation; however, what was and was not a species was sometimes difficult to decide, as Darwin himself had noted. He pointed to such ambiguous species as evidence of evolution.
More recent creationists have attempted to get around that problem by supposing a "created kind" to be some larger grouping, but even sites on "baraminology" do not give a clear idea of what "created kinds" there are.

  
lpetrich
Inactive Member


Message 59 of 69 (37921)
04-24-2003 6:17 PM


Creationist efforts to distinguish baramins will, I suspect, be endless will-o'-the-wisp exercises, something like the old controversy among preformationists between spermists and ovists. Preformationism is the theory that a complete organism exists in a gamete, an organism that has to grow. Of course, the next question is which gamete -- a sperm cell or an egg cell?
Here is a collection of assignments of hominid fossils to human and ape baramins. Notice creationists' serious differences in opinion -- and the difficulty of drawing the human/ape boundary line.
By comparison, consider this proposal to sequence several plant species' chloroplasts. Several of the species were selected to help resolve a contentious issue: how are the major groups of seed plants related?
Cycads
Conifers
Ginkgo
Gnetales (Gnetum, Ephedra, and Welwitschia)
Angiosperms (flowering plants)
The proposal mentioned no less that 15 proposed phylogenies, including one that states that Gnetales are derived conifers, the "gne-pine" hypothesis. And it argues that sequencing chloroplasts will provide a big bulk of genetic data, which will help determine which of the possibilities, if any, are right.
Finally, creationists like to use imprecise, informal terminology, without relating that terminology to mainstream-biology taxonomic terminology. Thus, when they talk about the "dog kind", are they referring to:
Canis lupus familiaris (domestic dog)
Canis lupus (with gray wolf)
Canis sp. (with coyote, jackals)
Canidae (with foxes and other canids)
?

Replies to this message:
 Message 60 by Brad McFall, posted 04-28-2003 12:06 PM lpetrich has not replied

  
lpetrich
Inactive Member


Message 61 of 69 (38544)
05-01-2003 4:33 AM


I regret not being able to respond to Brad McFall's postings in detail, because while he seems to be widely learned, his postings simply do not make sense. It's as if his mind is some sort of random-sentence generator.

  
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