alien at the bar: ...so the slightest exposure to our sweat will melt skin right off the bone
samus aran, absently twirling a lock of hair around her finger: wowww for real? :) like, how fast though
The evolutionary bio finding on mating success in birds is actually really fun here because bright coloration of plumage is one of the easier visual indicators for male birds to advertise how FIT they are. Since there's a legit survival cost imposed in resources and surviveability, the Sexual Selection hypothesis about Peacock tails is pretty compelling, and expanded outward the cool plumage coloration of Blue-Jays and Cardinals is pretty disadvantageous if you're trying to survive against birds of prey. Sexual selection is weird, did you know male Giraffes SLAM each other with their long muscular necks and the findings suggest it's done when competing for a mate?
brood parasitism is neat - and not always even "mean spirited" insofar as you can reduce evolutionary strategies played out over thousands and thousands of years as "mean."
a lot of the time it's just practical - if you're a nomadic species that had to follow something like herds of bison around to survive, building a nest in a tree and then settling down on it for a few weeks is probably not going to work out. you need to get creative
anyway i had the chance to watch a pair of brown headed cowbirds do their thing a couple years back. they were pretty bold - ejected the host bird's egg (pictured) literally right in front of me
