Sibling rivalry seems to exist in all families, whether human or non-human.. So why would animals want to compete, and maybe even kill their nearest relations??

This is the focus of the work of Douglas Mock. He is a Professor in the Department of Zoology at the University of Oklahoma and co-author of “The Evolution of Sibling Rivalry.”

Doug and Greg analyze some of our most intimate relationships in this episode, touching on scarcity mindsets, siblicide, birth order, and progeny selection.

Episode Quotes:

Why being wrong might help you find the right answers

So the advantage of being wrong is that it tells you that there's one or more variables you haven't been thinking through properly. And when you're right, you think, you pat yourself on the back and say, okay, that's wonderful. I must've understood everything perfectly. When you get answers exactly the opposite of what you expect, you realize, oh, I messed up. And that means that the entire literature that I read in preparing this prediction also was missing something, which means I have an opportunity to find out something subtle and interesting, and that everybody else has missed.

On defining siblicide

I defined it as something that involves significant amounts of overt aggression. So as opposed to just jostling or getting positioned for the next lump of food or out-consuming your rivals that are sharing limited budgets.

Technological leap in evolutionary biology

The biggest technological leap of all that has happened in evolutionary biology has been relatedness. The DNA assays of finding out who's related to whom and, in particular, where the male gametes are ending up in the population because nobody was quite sure who the father was of all of these nestling birds.

Show Links:

Recommended Resources:

Guest Profile:

Faculty Profile at the University of Oklahoma

His Work:

The Evolution of Sibling Rivalry feat. Douglas Mock

unSILOed with Greg LaBlanc