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→Genetic bottleneck
[http://www.pnas.org/cgi/reprint/90/8/3172.pdf the same in scientific terms]
[http://www.pnas.org/cgi/reprint/90/8/3172.pdf the same in scientific terms]
[[User:Totnesmartin|Totnesmartin]] 14:05, 15 May 2007 (EDT)
[[User:Totnesmartin|Totnesmartin]] 14:05, 15 May 2007 (EDT)
::A "genetic bottleneck" occurs when a certain species experiences an event that causes the entire species population to go nearly extinct. It can occur during processes of natural speciation (when few members of the population separate and start their own population) or from the introduction of a new natural predator. What happens is that after the near extinction event, the population gradually goes larger until eventually there are many more individuals and there is a substantial, self-sustaining species. We know that a genetic bottleneck has occurred, for example, in cheetahs because every animal has a very similar genetic make-up, which indicates that the entire cheetah species as we know it today originated from only a few individuals. This is also why cheetahs are generally prone to many familial conditions that result from inbreeding between genetically similar individuals. This last post is right to assume that if the story of Noah's arc were true, all species on this planet would exhibit similar genetic patterns. After all, what the Bible says is that Noah brought two of every animal on the arc and the rest drowned in the great floor. However, this is entirely not the case. Humans, for example, are by far the most diverse species on the planet due to the ease of international travel and mixing of different nationalities over the course of time. There are also 300,000 different varieties of beetles on this planet. Dogs and horses are just two more examples of species that maintain great genetic diversity, mostly through human intervention over thousands of years. Just another example of where the Bible got it wrong.
:::However, I know very little about the evolution of kangaroos. It sounds plausible, though, that a few kangaroos may have repopulated the entire species following the continental drift that separated Australia from the mainland.
==Rarely fossilize==
==Rarely fossilize==
Darwindude ... please cite your sources before adding information. It may be true, but you need to show that. [[User:Jrssr5|Jrssr5]] 21:11, 12 May 2007 (EDT)
Darwindude ... please cite your sources before adding information. It may be true, but you need to show that. [[User:Jrssr5|Jrssr5]] 21:11, 12 May 2007 (EDT)