Here’s something you may not know about large, flightless birds: they’re great dads.
Birds like ostrichers, emus and kiwis all belong to a group of flightless birds called “ratites”. Ratites lack a keel, which is an extension of the breastbone where flight muscles attach; hence, they cannot fly. Flying helps birds avoid predation, but it also consumes a lot of energy. So instead of developing wings, ratites grew in size to avoid attack.
And in many ratite species, it is the male who is responsible for child care.
“Only males take care of the chicks and incubate the eggs in all ratites except for ostriches and kiwi,” says Patricia Brennan, a biologist at the University of Massachusetts at Amherst. In many bird species, both parents raise the young, “while primary male care is rare,” Brennan says.
So aside from ostriches and kiwi, only the male ratites care for the offspring. But ostriches aren’t lazy fathers; each male has a primary female, with whom he takes turns incubating the eggs. Male ostriches don’t even care if the eggs aren’t his – if a female lays an egg in his nest, he’s caring for them, dammit.
Ratites are also among the three percent of birds that have penises. Most birds lost their penises over the course of history, and no one really knows why.
I could make a plethora of dirty jokes here – but I won’t.