Joined: Feb. 2006
|Quote (Dr.GH @ Nov. 08 2011,12:23)|
|Quote (Southstar @ Nov. 08 2011,09:39)|
Concerning you first example. The italian Sparrow, it derives from a hybridization of two other spieces.
To be a good point should it derive form internal mutation and not hybridization?
I'm shure that if I post it someone will come up with: well dogs have been crosed alot of times and obviuosly their jeans are mixed?
This might sound like a realy stupid question to you but please bear in mind that last time I looked at genetics was at school 8 years ago.
Why should hybrids be excluded? They are merely a way of combining genes, and gene variants. When this results in a self reproducing population with restricted out-breeding, it is 'macroevolution."
If creationshits start redefining "species," "evolution," and what ever else shows them to be fools, just bust them on their inconsistency.
But, there were dozens of other examples, use them if you prefer.
I've just finished reading a paper in the New Journal of Botany on the evolution and taxonomy of the narrow-leaved marsh orchid complex (within Dactylorhiza) in Britain, Ireland and the rest of Europe. These have all originated as allopolyploids of the same two diploid species in apparently four separate episodes. In other words, two species hybridise and the hybrid undergoes genome duplication, which results in instant reproductive isolation (more or less). Biogeographical and molecular evidence suggests that three species evolved after the last glacial maximum, whereas the fourth predates it. What's really interesting are the differences in ecological (habitat) preferences shown by these four species, which serves to further isolate each species from the others, setting them on separate evolutionary trajectories.