spider sex...

When it comes to spiders, smaller is better when it comes to male spiders.  This does not migrate into the human realm were bigger is better :-)

BBCnews...

In some species of spider, males are far smaller than females; now, scientists think they know why.

A group of Spanish researchers says evolution favours small, light males because they can more easily traverse thin strands of silk.
But large females are favoured because they reproduce more abundantly.
Writing in the journal BMC Evolutionary Biology, the researchers say their finding helps to explain why this trait is so widespread among spiders.
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