[sirchtruth]

Why that particular condition?

My understanding of what science does is "observe" before they form hypothesis. Since evolution of man has never been "observed", nor has there ever been any intermediate species still alive, ever shown, I'm wondering how science concludes evolution is "fact?"

[Fester Chugabrew]

I'm wondering how science concludes evolution is "fact?"

The amount of circumstantial evidence is sufficient enough to warrant strong convictions. What puzzles me is how the proponents of evolution arrive at the notion their view of history deserves exclusive hearing in public schools when even our Constitution does not guarantee as much.

[Coyoteman]

Since evolution of man has never been "observed", nor has there ever been any intermediate species still alive, ever shown, I'm wondering how science concludes evolution is "fact?"

Because of all the intermediate species which are represented in the fossil record. Many of these, for example:

Figure 1.4.4. Fossil hominid skulls. Some of the figures have been modified for ease of comparison (only left-right mirroring or removal of a jawbone). (Images © 2000 Smithsonian Institution.)

(A) Pan troglodytes, chimpanzee, modern
(B) Australopithecus africanus, STS 5, 2.6 My
(C) Australopithecus africanus, STS 71, 2.5 My
(D) Homo habilis, KNM-ER 1813, 1.9 My
(E) Homo habilis, OH24, 1.8 My
(F) Homo rudolfensis, KNM-ER 1470, 1.8 My
(G) Homo erectus, Dmanisi cranium D2700, 1.75 My
(H) Homo ergaster (early H. erectus), KNM-ER 3733, 1.75 My
(I) Homo heidelbergensis, "Rhodesia man," 300,000 - 125,000 y
(J) Homo sapiens neanderthalensis, La Ferrassie 1, 70,000 y
(K) Homo sapiens neanderthalensis, La Chappelle-aux-Saints, 60,000 y
(L) Homo sapiens neanderthalensis, Le Moustier, 45,000 y
(M) Homo sapiens sapiens, Cro-Magnon I, 30,000 y
(N) Homo sapiens sapiens, modern

[b_sharp]

"My understanding of what science does is "observe" before they form hypothesis.

Yes this is a part of science but by no means the only or most important part of science. Much of science is based on not direct observation but on indirect observation which is frequently the preferred method. Quantum physics is the prime example of this.

Science also takes a larger problem and breaks it into smaller more easily controlled parts and runs tests on those parts. This kind of experimentation has been done many times for Evolution. The number of mutations, the type of mutations and the ability for mutations to produce significant changes to morphology has been tested in the lab. The ability for selection to increase the frequency of a specific allele within a population has also been successfully tested many times.

"Since evolution of man has never been "observed", nor has there ever been any intermediate species still alive, ever shown, I'm wondering how science concludes evolution is "fact?"

Evolution, despite the protestations of creationists who really don't have any input into the science, is the change in allele frequency within a population due to differential reproductive success. This has been observed many times in the wild.

Evolution is also about speciation (I use here the scientific definition, not the creationist definition) which has also been observed numerous times, both in the lab and in the wild.

These observations are indeed fact. How those observations relate to each other and what processes are behind them is the theory. A scientific theory.

Why would you expect an intermediary species to still be alive? The SToE predicts that, given the same geological space, where there are two similar (similar needs and constraints, not necessarily morphology) and competing species, one will 'out compete' the other unless some evolutionary stable strategy (a strategy where the payoffs are higher than any other strategy) develops which benefits both populations. Humans have pretty much dominated every relationship with other species they've had for 30,000 years or more. There are no intermediate species because we have simply out competed them.