Thanks to Ari for suggesting this week's episode, about the peacock!

Further reading:

Peacock tail feathers shake at resonance and hold eye-spots still during courtship displays

Indian peafowls' crests are tuned to frequencies also used in social displays

An ocellated turkey (not a peacock but related):



An Indian peacock male:



An Indian peahen with chicks [photo from this site]:



Close-up of a male Indian peacock's crest [photo by Jatin Sindhu - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=49736186]:



A male Indian peacock with train on display [photo by Thimindu Goonatillake from Colombo, Sri Lanka - Peacock Dance, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=19395087]:



A green peacock [photo from this site]:



The mysterious Congo peacock [photo by Terese Hart, taken from this site]:



Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to talk about a beautiful bird that almost everyone has seen pictures of, and a lot of people might have seen in zoos and parks. It’s a suggestion by Ari, who wants to learn about the peacock!

The name peacock is technically only used for the male bird, with the female called a peahen and the birds all together referred to as peafowl. Most people just say peacocks, though, because the male peacock has such a fabulous tail that it’s what people think of when they think of peafowl. I’m happy to report that baby peafowl are called peachicks.

The peacock most people are familiar with is native to India, specifically called the Indian peafowl. It’s a surprisingly large bird, with a big male weighing more than 13 lbs, or 6 kg. Females are smaller. It’s the size of a wild turkey and in fact it’s related to the turkey, along with pheasants, partridges, and chickens. Back in episode 144 we talked about a bird called the ocellated turkey, a brightly colored turkey that lives in the Yucatan Peninsula, which is part of Mexico. The male’s tail feathers have the same type of colorful eyespots seen on a peacock’s tail.

But the peacock’s tail is way bigger than any turkey’s tail. It’s called a train and most of the time it’s folded so that it’s not in the way. A big male can grow a train that’s much longer than the rest of his body, more than five feet long, or 1.5 meters. Most of the train’s elongated feathers end in a colorful eye-spot, around 200 of them in total. The eyespot pattern really does resemble a big eye, with a dark blue spot in the middle surrounded by a ring of blue-green and a bigger ring of bronze. The bronze color is surrounded by pale green and the rest of the feather is a darker green. As far as we know, the eyespots aren’t supposed to look like eyes the way some animal markings are. A leopard or other predator doesn’t attack the tail thinking it’s a peacock’s head. It’s just a pattern.

For a long time scientists were divided as to what the peacock’s train was really used for. Not everyone thought it was for showing off for peahens. Some thought it was just for camouflage in the jungle. The main confusion was why the peacock would grow such a long, conspicuous train, which can be a hindrance to him in thick undergrowth and can attract the attention of predators. But many male birds have long, ornamental tails that may impede their mobility, such as various bird of paradise species, that are definitely meant to show off for females. This appears to be the case for the peacock too.

During mating season, male peacocks gather at what’s called a lekking site, where they hang out waiting for females. When a female approaches a male, he spreads his train into a fan and shivers it, which rattles the feathers together and also shows off the iridescent colors. The male struts around, showing off his tail, and the female may ignore him completely or take a good look at his tail. In studies where scientists snipped all the eyespot...