Evolution vs. Creation: Proof Needed

[Ceridwen018]

Does anyone have a specific claim as to what "microevolution" and "macroevolution" are? How could you tell which one you were looking at?

Microevolution is a subtle genetic variation. Animals which are separated by microevolution are still considered members of the same species, and they can still successfully breed. For instance, Black Labs and Chow Chows look very different, are adapted to different environments, and have slightly different instincts, but both are still members of the canine species and the two breeds are still able to produce fertile offspring.

Macroevolution, on the other hand, occurs when microevolution progresses so much, (aka, two members of the same species become so different), that they can no longer produce fertile offspring. For instance, horses and donkeys can breed, but their offspring, (mules), are infertile. Also, the okapi and the giraffe are related, however they cannot breed at all.

[JerryL]

Macroevolution, on the other hand, occurs when microevolution progresses so much, (aka, two members of the same species become so different), that they can no longer produce fertile offspring. For instance, horses and donkeys can breed, but their offspring, (mules), are infertile. Also, the okapi and the giraffe are related, however they cannot breed at all.

OK. Then that's easy to address as macroevolution has been directly observed:

Seedless grapes (pretty self-explanitory)

Salmon (http://www.umass.edu/newsoffice/arc...1900salmon.html)

Goatsbeard ("Three species of wildflowers called goatsbeards were introduced to the United States from Europe shortly after the turn of the century. Within a few decades their populations expanded and began to encounter one another in the American West. Whenever mixed populations occurred, the specied interbred (hybridizing) producing sterile hybrid offspring. Suddenly, in the late forties two new species of goatsbeard appeared near Pullman, Washington. Although the new species were similar in appearance to the hybrids, they produced fertile offspring. The evolutionary process had created a separate species that could reproduce but not mate with the goatsbeard plants from which it had evolved.")

and Mosquitos (having a little trouble trakcing down that one, it was on ABC news's site recently (2-3 months ago) in an article on the effects of global warming. Let me offer some more to make up for it.

Two strains of Drosophila paulistorum developed hybrid sterility of male offspring between 1958 and 1963. Artificial selection induced strong intra-strain mating preferences. (Test for speciation: sterile offspring and lack of interbreeding affinity.) Dobzhansky, Th., and O. Pavlovsky, 1971. "An experimentally created incipient species of Drosophila", Nature 23:289-292

Rapid speciation of the Faeroe Island house mouse, which occurred in less than 250 years after man brought the creature to the island. (Test for speciation in this case is based on morphology. It is unlikely that forced breeding experiments have been performed with the parent stock.) Stanley, S., 1979. Macroevolution: Pattern and Process, San Francisco, W.H. Freeman and Company. p. 41

Formation of five new species of cichlid fishes which formed since they were isolated less than 4000 years ago from the parent stock, Lake Nagubago. (Test for speciation in this case is by morphology and lack of natural interbreeding. These fish have complex mating rituals and different coloration. While it might be possible that different species are inter-fertile, they cannot be convinced to mate.) Mayr, E., 1970. Populations, Species, and Evolution, Massachusetts, Harvard University Press. p. 348

page 22 of the February, 1989 issue of Scientific American. It's called "A Breed Apart." It tells about studies conducted on a fruit fly, Rhagoletis pomonella, that is a parasite of the hawthorn tree and its fruit, which is commonly called the thorn apple. About 150 years ago, some of these flies began infesting apple trees, as well. The flies feed an breed on either apples or thorn apples, but not both. There's enough evidence to convince the scientific investigators that they're witnessing speciation in action. Note that some of the investigators set out to prove that speciation was not happening; the evidence convinced them otherwise.

[Ceridwen018]

Great post, JerryL! Of course most of the different organisms where macroevolution has been observed are either plants or insects due to their relatively short generations and large numbers of offspring. The same standards hold true for mammals, reptiles, etc., though. Scientists try their best to trace these animals back to their ancestors using fossils, and new discoveries are made every day!