Animal Parenting: Teat Ownership

Nature encourages competition, because the fiercest competition brings out the best in each of us. And the will to fight for the best is evident even among baby animals--the competition to get shelter, the best food, err, in this sense, teat.

What is teat ownership?

When you have a litter of babies, one takes top left nipple, another takes top right, and never shall they switch. Biologists had hitherto thought that teat ownership reduces fighting, as everyone can have their own teat. This behavior is ubiquitous in mammals--cats, pigs, dogs, sheep... and.. binturongs.

Image: news.nationalgeographic.com 

Patricia A. Schoknecht from the Department of Biology, Virginia Polytechnic Institute and State University set up a nest and observed a litter of baby binturongs via video camera as they grew up, and looked at their behavior especially when suckling.

She observed that the cubs were fastidious about their teat, and generally stuck to it. Most cubs in her sample preferred to suckle on the rear left teat, and they fiercely protected it against other cubs once they've won it. The author also weighed the cubs as they grew up, and the result justified the fuss 'round the teat.

Image: zooborns.typepad.com

Two of those cubs that suckled on the left rear and the right rear outweighed substantially than the others. The author suggests that those two teats give better milk (higher in fat) than other teats.
So teat ownership is not just about reducing fighting among baby animals, it also encourages healthy competition (unless one of those babies dies) to obtain the best food. And better food means stronger, healthier baby.

Lucky for humans, we generally do not have to fight for it, unless you have a twin.


Malcolm
info: Growth and teat ownership in a litter of binturongs.  Patricia A. Schoknecht, Zoo Biology, volume 3, issue 3, pages 273–277, 1984