Birds Caught in the Act of Becoming a New Species (http://www.sciencedaily.com/releases/2011/12/111208121408.htm)
QuoteScienceDaily (Dec. 8, 2011) — A study of South American songbirds completed by the Department of Biology at Queen's University and the Argentine Museum of Natural History, has discovered these birds differ dramatically in colour and song yet show very little genetic differences, indicating they are on the road to becoming a new species.
"One of Darwin's accomplishments was to show that species could change, that they were not the unaltered, immutable products of creation," says Leonardo Campagna, a Ph.-D biology student at the Argentine Museum of Natural History in Buenos Aires, who studied at Queen's as part of his thesis. "However it is only now, some 150 years after the publication of his most important work, On the Origin of Species, that we have the tools to begin to truly understand all of the stages that might lead to speciation which is the process by which an ancestral species divides into two or more new species."...
Research continues to validate both the existence of process of evolution and to substantiate the Theory of Evolution that explains the process.
Nice find. Cheers Tank. :)
I think speciation simply occurs when the genomes reach a point where they are "too different" for the egg and sperm to successfully fuse together. IMO, if we continue to breed St. bernards with St. bernards and poodles w/ poodles and keep them reproductively isolated, and artificially select them to evolve in completely different directions, there will be a point when a St. bernard can no longer breed w/ a poodle and produce viable offspring.
Quote from: yodachoda on December 24, 2011, 04:36:34 AM
I think speciation simply occurs when the genomes reach a point where they are "too different" for the egg and sperm to successfully fuse together. IMO, if we continue to breed St. bernards with St. bernards and poodles w/ poodles and keep them reproductively isolated, and artificially select them to evolve in completely different directions, there will be a point when a St. bernard can no longer breed w/ a poodle and produce viable offspring.
It depends what you mean by 'successfully'. A donkey can mate with a horse and produce a mule, but the mule is infertile. So the egg and sperm did fuse but the offspring was not evolutionarily viable.
Quote from: Tank on December 24, 2011, 07:40:21 AM
It depends what you mean by 'successfully'. A donkey can mate with a horse and produce a mule, but the mule is infertile. So the egg and sperm did fuse but the offspring was not evolutionarily viable.
True. Yet with your important clarification in place, yodochoda's point is one to keep in mind. Phenotypic variation is interesting, informative, and useful to study, yet can be misleading with regard to speciation. If the two creatures will mate without human intervention, and their sexual apparatus are compatible, and sperm and egg can fuse, and live, fertile* offspring can result, and one or both parents without human intervention will do whatever is necessary to shepherd the offspring to maturity, then these two creatures can reasonably be considered the same species, just possibly different breeds, if they look very different from one another.
* Your clarification is always important.
Still looks like a bird to me I didn't see any crocodile parts.
What is amazing to me is that we will study birds to find proof of Evolution, but are we taking a look at the changes in humanity for proof of evolutionary change right in front of our eyes? (or behind them?) :o
Would aspergers syndrome/autism be sufficient for the beginnings of a human speciation?
Quote from: Wessik on January 17, 2012, 04:17:46 AM
Would aspergers syndrome/autism be sufficient for the beginnings of a human speciation?
Only if it lead to a reproductive advantage for those with aspergere/autism. As far as I understand it does not so it is not going to lead to speciation.