PLEASE help: Evolution Questions

[LiL Homie]

1. Why does allopolyploidy pobably produce more variation than autopolyploidy?

2. How can disruptive selection lead to speciation in sympatric populations of the same species?

3. What may be a reason for the fact that human populations have much less genetic divergence than other species of animals?
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1. ? I think it's because allopolyploidy is more common, whereas autopolyploidy is rare. Also something to do with the fact that autopolyploidy happens within a species but allopolyploidy happens within different species interbreeding.

2. ?
3.?

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Can someone please check what I have & explain these others to me. I don't think I understand these concepts properly, so I'm having difficulty answering these. My book isn't doing me any justice, it's confusing me more.
I would really appreciate the help. Thank You! = )

[JDavidE]

Well, I'd give you seven out of ten for the only question you've ventured an answer for.
An allopolyploid is a hybrid with its sets of chromosomes being derived from different species. An autopolyploid derives its chromosome set from a single parent species. So, with more to work with, the chances of variation are greater with an allopolyploid

[Darby]

For question 3, think about how reproductive opportunity works in human beings (how powerful is sexual selection at "weeding out" certain mixes of genes?), then factor in natural selection considering that humans tend to largely adapt the environment to their needs rather than being forced to adapt themselves.