The first video, called to my attention by reader Michael, describes the adaptive significance of the huddling of emperor penguins (Aptenodytes forsteri), the only penguin that breeds during the Antarctic winter (May-August). Laying eggs at that time, and rearing the chicks, these birds face some of the coldest temperatures on Earth. They deal with the cold, in part, by forming huge and ever-shifting huddles in which the outer penguins move to the warmer inside, and the inside penguins, getting too ho—temperatures can go up to human body temperature 37° C, in the middle—shuffle to the periphery.
This first video gives a nice demonstration of the conservation of warmth through huddling—using coffee cups. The coffee-cup experiment lasts until 1:40, and then it’s onto the penguins. The endless shifting of position is like an avian ballet:
This PBS “Nature” video concentrates solely on the penguin themselves, huddling while they’re holding the chicks on their feet. What wonderful photography! I’d love to see this some day, but few people get to see these birds even in warmer seasons, for they don’t breed in accessible places.
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These are like religious pilgrims milling about the supposed center of the universe. A great, icy Hajj.
What a simile! Award yourself an extra dip in the “treat” drawer of the fridge tonight.
Treat drawer would be the freezer. Moose tracks ice cream!
Learning how to live in the deadly cold.
This appears to me as a clear cut case of group selection. I know that group selection is controversial, and I don’t think Jerry likes the concept, but nevertheless … It’s not one group pitted against another, but an adaptation *as a group* pitted against the environment. If the penguins could not act cooperatively, as a group, refraining from selfish, cheating behavior, the group wouldn’t survive. If there were another similar species without this cooperative behavior, in the same environment, they’d lose.
Just a guess but I am thinking it’s not like Kin selection because there is no opposing group. But it is certainly a survival behavior that all must participate in. You take part or die.
A single pair of Emperor penguins has effectively zero chance of reproducing, but the same is true for many species of birds and other animals. I’m puzzled the resistance to even the idea group selection.
Yes but the conditions they live in were a product of gradual climate changes & the penguins would already have been used to living in groups. There was never going to be a sudden pairing in cold conditions off a solitary couple.
There are other explanations, as in other cases of mass group behavior. You apparently don’t want to hear them as you’ve seem to have decided what this is, but I can easily envision an individual-selection argument that could produce this behavior.
I’d very much like to hear them. They might be convincing, but individual selection doesn’t preclude group selection. Group selection could be, and in my view probably is, an emergent property.
I believe Stephen that the explanation for how this collective behavior evolved is something like Hamilton’s selfish herd theory with the deadly Antarctic winter substituting for peripheral predation. If so, no group selection needed.
https://en.m.wikipedia.org/wiki/Selfish_herd_theory
… but is it not the individual that benefits from this group behaviour or more precisely their genes. The survival of the individual increases as they have ‘chosen’ to place their nursery in such a relatively predator free but hostile environment. Every individual benefits including kin (which may have been the catalyst for the behaviour) by co operating and working together.
My guess is that they adapted to the cold rather than move the breeding site, & they ended up in a situation that means they cannot adapt to future changing conditions, being now wedded to this behaviour. You can be forced to adapt by moving a breeding site as the climate cools, or stay put & accept the different set of problems. They ‘chose’ the latter, but as climate change occurs this means a whole lot of new issues & problems.
Thanks for the videos, fascinating survival behavior.
Me too.
Oddly, I’d hear this very factoid (the huddle getting too hot) on Friday too. Small world.
Watching these penguins huddle and shift, is anyone else reminded of the Spartan phalanx formation?
Hate to be the christmas nazi here (not really) but it is colley birds not calling birds. Same root that the word collier comes from meaning black. Old english for black bird.
I’m going to out-Christmas-nazi you. 🙂
“The Twelve Days of Christmas” was first published around 1780 in the book Mirth Without Mischief, where it refers to “colly” birds, not “colley” birds.
Thanks for making me look it up. 🙂