Hello kakariki, and welcome to the forum, thanks for the kind comments.


The space occupied by any population must necessarily be at least slightly different for each organism - they can't occupy the same space, and the ecology is not constant.

Do a google on "cryptic species" -- when they were initially researching malaria and the transmission by mosquitos they were perplexed by the fact some populations of the suspected species were not linked to outbreaks. Then they discovered that they had not one but three morphologically identical species, one of which was the carrier while the other two were non-carriers.

What is frequently theorized is that while the sub-populations occupy the same ecology, they have different behavior that leads to breeding isolation. In this case the three species of mosquito were found to breed at different times of the day.

One can also theorize that sexual selection for a variation of a trait can cause different members of the same population to prefer different mates ("gentlemen men prefer blonds"?), and that this could over time result in breeding isolation even though they occupy the same ecology.

You need to think of the ecology as multi-dimensional -- 3 space dimensions, 1 time dimension, and 1 (or more) behavioral dimension/s, so that when you map sympatric speciation the daughter populations cover different 5(+)D-spaces.

Some biologists think that all speciation mechanisms are really allopatric speciation and it just differs on how you define the geography (topology).

Hope that helps, it's off the cuff, and if you are interested in more I can suggest another site with genetic biologists on board.

Enjoy.
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