I love this article ...
"Apparently, zebra finches (above) understand
that it's not about the coloring or the shape
of a potential mate's tail feather, but how one shakes it.
A research conducted by a team from University of Exeter, Carleton University, Royal Veterinary College, and University of London has found that adventurous female zebra finches choose mates with similar personalities, regardless of the birds' size or physical features. This is the first study to show that the non-sexual behavior or personalities of both mates influences partner choice in non-humans.
By setting up behavioral tests for more than 150 zebra finches, the team discovered that females who are willing to explore new environments are more likely to spend time with similarly outgoing and confident males. In the experiment, each female watched a pair of brothers exploring strange cages, one of which was made to look less exploratory by restraining it in an invisible box. The females were then put together with the brothers, where the team observed which male the females were more likely to favor. While the more adventurous female finches preferred the bold male birds, the less exploratory females didn't show a preference for either.
Team leader, Dr. Sasha Dall of the University of Exeter said: "This is strong evidence that females care about the apparent personality of their male independently of his appearance. We have the first evidence that it is important for partners to have compatible personalities in the mating game. This is something we would probably all agree is the case for humans but which has been overlooked for other species."
Birds of a feather do flock together. Though the feather in question doesn't seem to matter too much."