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To: Virginia-American
"Concrete examples, please."

New Guinea man.

The drawings of human embryos that look like different creatures but have been known to be false for a long time, but still get put in school science textbooks. There are a lot of them.

299 posted on 02/05/2004 7:04:36 AM PST by DannyTN
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To: DannyTN
You: It is unfortunate that embellished stories circulate amoung creationists. But I should note that occurs in the evolutionists camp as well.

Me: "Concrete examples, please."

You: New Guinea man.

New Guinea man is something I never heard of before. So I did a Google search. Most of the hits were Papuans, anthropologists, and so forth. Nothing having to do with human origins. Except one: Review of Jack Chick's "Big Daddy" at talk.origins. Surely you have more info than a Jack Chick tract!

(BTW, my opinion of Chick is that he has driven many more people *from* Christ than the secularists, commies, usual suspects could ever dream of.)

But seriously. "New Guinea Man"? A modern H. sapient skull something like 5000 years old. Please provide a link to some "embellished story" about it, and I don't mean Jack Chick.

You: The drawings of human embryos that look like different creatures but have been known to be false for a long time, but still get put in school science textbooks.

I ask for concrete, and get jello. Anyhow.

Presumably, you're referring to Haeckel's infamous drawings of embryos. an article about them According to this review of "Icons of evolution" "Haeckel's drawings are seldom if ever still printed in biology textbooks and when they are, they are there for historical reasons or as an wxample of the human falllibility aspect of science."

You do, of course, have some *specific*, *modern* counterexamples, don't you?

Now let's get away from Ernst Haeckel and look at some actual science. Embryology - the study of how complex things develop from single cells. Part of embryology is called von Baer's laws:

"Karl Ernst von Baer was the foremost German embryologist of the first half of the 19th Century. After carefully comparing the chick embryo to other vertebrates, he came up with four generalizations about vertebrate development. The photograph above comes from Scott Gilbert's Developmental Biology, 6th Edition (p. 10) von Baer's generalizations are:

The general aspects of a large group of animals appear earlier in embryonic development than do the more specialized ones.
Less general characters develop from more general ones.
The embryos of a particular species diverge more and more from those of other animals as development proceeds.
The young embryo of a "higher" animal is not like the adult of a "lower" one, but instead resembles its early embryo."

Source

These are called "laws" because they are simple observations, no theory trying to explain them. (this is the usual scientific terminology: Boyle's' law is an experimental result - it was later explained by the kinetic theory of gases. Ditto Kepler's laws, Bodes' law, etc)

Haeckel was trying to show that embryos resemble their adult ancestors, von Baer that they resemble their ancestors' embryos.

A specific example of this is the human (as an example of a mammalian) ear:

"In addition, in mammals only, the quadrate bone and articular bone shift off the jaw to become part of the ear. This shift is not a profound one in terms of distance, as the ear is so close to the jaw joint. The quadrate becomes the incus and the articular becomes the malleus. "

source

In other words, reptile and mammal embryos have what appear to be the same bones in the same positions. Then, in mammals, they move to become our ear bones.

The really interesting thing is that much later fossils were found with the jaw/ear bones in intermediate configurations in adults - these are the so-called mammal-like reptiles.

So Haeckel may have been exaggerating, but there is definitely a sense in which "ontolgeny recapitulates phylogeny".

There are other examples as well: the recurrent pharyngeal nerve goes from the neck, down into the chest, loops around the aorta, and comes back up to the throat. This adds something like 15 feet to it in giraffes! Its embryological development makes the reason for this obvious - in fish it doesn't take such a lengthy path, neither does it in early embryos; but the proportions change as we mature, and the nerve is stuck and can't change its path (I couldn't find an on-line illustration of this)

Surely you have no problem replacing Haeckel's misleading drawings with modern photos to illustrate these fascinating topics of biology.

Our embryos resemble tadpoles which resemble fish, embryonic horseshoe crabs are called 'trilobites' because they resemble extinct trilobites, immature insects resemble worms... definitely some food for thought here

334 posted on 02/07/2004 12:21:41 AM PST by Virginia-American
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