This is anecdotal and I cannot find anything on the web, but interesting. Hopefully someone will know something about this.
My mom
has family in Louisiana. After her last visit she told me that the fire ants in the area had stopped forming above ground mounds, much to the chagrin of those trying to kill them.
This seems to me to be an increase in complexity due to the selective preasures of extensive poisoning by humans.
Here's how I figure:
Fire ant behavior is all nature, no nurture.
The fire ants still construct underground colonies, but with no visible structure above ground. This means that the material excavated in building those colonies must be disposed of in such a way as to not form a mound above ground. As I see it, the ants must hide that material-- carry it away from the mound and scatter the material. This is more complicated behavior than simply depositting it at the opening of the tunnel.
The selective pressure driving this change is the poisoning. Forming a mound is effectively drawing a target around oneself.
Any comments, or infomation?
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