How to Survive a Mass Extinction

How Animals Have Survived Mass Extinctions
The small, stocky Lystrosaurus managed to survive a completely inhospitable environment by heading underground.
The small, stocky Lystrosaurus managed to survive a completely inhospitable environment by heading underground.

Survivors of mass extinctions are in a pretty elite club. And unlike today's doomsayers, they didn't have guns, bomb shelters or food storage to help them out. What is it they were doing right?

To answer this question, let's look at Lystrosaurus, one of the greatest survivors of all time. This creature was a part of the lucky group that survived the Permian event, which, if you recall, killed 96 percent of all species on Earth. Especially surprising is that Lystrosaurus wasn't a tiny algae or insect: It was a mammal-like reptile about the size of a pig, basically the only animal of its kind to dodge extinction.

Lystrosaurus had a number of things going for it. One was that it was a burrower. As any survivalist worth his or her salt can tell you, underground is a pretty good place to be when something bad happens. Plus, breathing underground was good form during the Permian event, when low oxygen levels and dusty airborne contaminants became the norm.

Another tool in Lystrosaurus's survival kit was its ability to move and spread out over great distances. When things got bad, the creature was evidently capable of waddling to safer climes, eventually inhabiting areas all over Earth's super-continent, Pangea. And how was it able to adapt to so many places? A big reason is that it was a generalist species, meaning, among other things, that it wasn't a picky eater. Although it ate only plants, its beak-like mouth was equally effective at chomping down rough vegetation and digging for roots.

Other species have survived mass extinctions by virtue of their small size. Obviously, little creatures don't need as much food as their larger counterparts (think mice versus elephants). They also tend to reproduce more, which gives them a larger, more genetically varied population that can adapt more quickly and effectively to change.

In a lot of ways, mass extinction survival just came down to luck. Certain species had certain traits that helped them endure whatever awful things befell the Earth. So is the survival of the human race really just a game of chance?