March Mammal Madness Is The Only Bracket You Need

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There will be a lot of tournament brackets for random things in the coming weeks, pitting the best of everything from booze to TV shows to, I don’t know, cake or some shit. You can safely ignore all those brackets. This is the only one that matters: A 67-animal bracket that pits mammals* against each other in simulated battles to the death** to determine which mammal reigns supreme. Ladies and gentlemen and hairy, milk-producing orders of all ages, I give you the fifth annual March Mammal Madness.


Biologist Twitter is the only good Twitter, filled with good vibes and an urge to teach and lots of really cool animal photos. But even scientists who spend their lives studying these creatures can’t resist the urge to imagine how they’d do trying to beat the shit out of one another. Truly, conducting involved thought experiments about animals fighting is the thing that makes us human.

The bracket is above (here for hi-res), and here’s how the winners of each round will be determined:

Scientific literature is cited to substantiate likely outcomes as a probabilistic function of the two species’ attributes within the battle environment. Attributes considered in calculating battle outcome include temperament, weaponry, armor, body mass, running speed, fight style, physiology, and motivation.


In the earlier rounds, the better-ranked seed has home-ecology advantage. For the final three rounds, the battlefield will be chosen at random.

Running the tournament will be Dr. Katie Hinde, Associate Professor, School of Human Evolution & Social Change, Center for Evolution and Medicine, Arizona State University; Dr. Josh Drew, Lecturer, Department of Ecology, Evolution, and Environmental Biology, Columbia University; and Dr. Chris Anderson, Assistant Professor, Department of Biological Sciences, Dominican University. They’ll be joined by a host of other “battle narrators” to give realistic outcomes from each match-up, and maybe teach you a little something about the animals at the same time.

You can follow along with the tournament at its website, or on Twitter. Past winners include the tundra wolf, the Sumatran rhino, and a hyena clan. Place your bets now, though I really don’t see how anyone takes this from the Sabertooth Cat. (Yes, there are extinct mammals in here, as well as mythical ones.)

*So, it’s only mostly mammals. The Gila monster is in this tournament. Because it’s cool, that’s why.


**They don’t necessarily fight to the death, either:

The battles are NOT always “nature, red in tooth and claw.” Sometimes the winner “wins” by displacing the other at a feeding location, sometimes a powerful animal doesn’t attack because it is not motivated to- a few years ago in the “Who in the What Now?” Division we had a dhole lose to a binturong because the night before dhole had gorged on babirusa and the gut passage time of wild-canids being 24-48 hours. This meant that the dhole was still full from the night before and unwilling to take the risks of tangling with the binturong. Even a small claw cut or bite wound can get infected and lots of times an animal will back down rather than take a risk for little potential benefit.


See, I told you this is scientifically rigorous. Now bring on the animal fights!

[Mammals Suck]