JP2

This post is the result of somewhat idle curiosity, but please, indulge me.

I understand that evolution stands as the accepted theory within the virtual entirity of the scientific community which best explains the origin of species as we know them, but I was wondering if there is any opposition to this theory by renegade scientists who believe that they have formulated a more accurate theory to explain this phenomenon? I'm not talking about religious or theistic theories in this case (i.e. Creationism), but was really wondering if there is any opposition to the evolutionary theory amongst members of the repuatble scientific community, and just how valid this opposition is?

In short, is there a well-developed theory that disagrees with both the theory of evolution and religious creationism (of all denominations)? Or is the evolutionary theory so well developed and so corresponding to real world evidence, that there is simply no room for any valid objections to it (except amongst those possessed by their own religious insanity of course) and thus no chance for recourse to an alterntive theory for the origin of species?

I hope that made sense.

Doubting Didymus

Physicists sometimes think they can disprove evolution. Not exactly an alternate theory, but that's physicists for you.

Colander of Truth

Yes it does. But you have to be careful with the word "theory." In colloquial use, theory means a "supposition;" a hypothesis, a guess. I have a "theory" that the Bills will eventually win a super bowl, before I die ....

A theory, scientifically speaking, is the result of formulating a hypothesis (or two), experimental testing of same, publishing results, findings and conclusions, and then by replicating the experiment, your theory is corroborated.

I can't imagine the times the basic mechanics of evolution has been experimentally replicated. Millions?

I brought this all up to say that an opposing theory will need to explain all the "apparent" results of the TOE as it stands. Certainly, you can have an opposing hypothesis. An opposing theory just flatly does not exist.

There is debate within the theory about particulars, as there is with anything of increasing complexity. However, the basic pricinples of evolution are so well founded, you would have heard any valid theory in opposition in a loud way.

The more interesting debate is in biogenesis. Fro a good read on evolution and biogenesis, try "The Fifth Miracle," Paul Davis? I can't remember .... He's an astrophysicist who reviews the laws of thermodynamics in depth - evolution is not a problem there ....

Good luck finding one!

Bob

Peez

Hi JP2,

I would like to add that Origin of Species presented two distinct ideas: descent with modification from common ancestors, and the mechanism of natural selection. The former is often called the fact of evolution, because it is a hypothesis that has passed so many tests (and never failed one). One might consider a particular model of specific lineages in the "tree of life" as a theory, in the sense of an explanation (based on reasoning and evidence) of a range of observations. However, what we typically refer to as the theory of evolution is the proposed mechanism by which descent with modification proceeds. Very generally, it refers to mutation, natural selection, and genetic drift, but it is very complex and some aspects remain to be understood. That being said, the fundamentals of the theory of evolution are universally accepted among evolutionary biologists.

It is interesting to note that there were other scientific hypotheses and theories about evolution before Darwin (he was not the first to propose that organisms evolve). In particular, Lamark proposed that species started by spontaneous generation and evolved in separate lineages (without common descent). He also proposed that living species have an innate drive to evolve "up" (at that time many biologists believed that some organisms are "higher" than others), and those species that are now "higher" have just been evolving longer. Finally he suggested that this evolution could be fine-tuned by the inheritance of acquired characteristics (each generation of giraffe had longer necks because their parents were always stretching their necks, because of some vital fluid that accumulated in the neck and was somehow passed on to the offspring). It is this latter idea that Lamark is best known for.

Peez

Doubting Didymus

My textbooks credit lamark for the original proposal of common descent. What is going on?

Quetzal

DD: pz is correct. Lamarck's "common descent" was predicated on one species transforming itself into another species. Orthogenesis at its finest. Lamarck's central tenet was that "lineages arose by a continual process of spontaneous generation and were transformed from very simple to more complex forms by an innate natural tendency toward complexity caused by 'powers conferred by the supreme author of all things'" (from Futuyma, "Science on Trial" 1995 ed, pg 28).

Peez

I am sure that pz is a fine fellow, but he's not me.

There may be more than one way to use the term "common descent". According to Lamark, modern leopards and modern lizards did not share a common ancestor, but he did propose that modern leopards might have had an ancient lizard ancestor.

Peez

P.S.: DD, what textbooks are you referring to?

[ December 05, 2002: Message edited by: Peez ]</p>

Doubting Didymus

It was a tiny note in the history of biological science section at the start of my university textbook. I think its an australian book, Knox et.al. 2001 Biology 3rd edition.

So what is the extent of Lamarks common descent proposals? (obviously I knew that orthogenesis is involved, but I was under the impression that he had some extant species related by ancestry)

Teach me!

pz

As you say, Lamarck did not propose the branching pattern of descent with which we are familiar. Every modern species was the product of a unique and complete lineage which was independently created. Each of those lineages had gone through historical transformations, but were still autonomous.

I'd say it is completely wrong to credit him with the idea of common descent. Transformationism, though, was definitely his baby.

Doubting Didymus

Interesting. That will teach me to trust a textbook.