The Virginia opossum is not the brightest of animals. When they are threatened, they pretend to be dead, which is where we get the expression "playing opossum." Sometimes, they do this in response to threats from oncoming traffic, which results in opossums becoming roadkill.

The next time you see a opossum playing dead on the road, try your best to avoid hitting it. Because it turns out that opossums are allies in the fight against Lyme disease.

Possums, like many other small and medium sized mammals, are hosts for ticks looking for a blood meal. But opossums are remarkably efficient at eliminating foraging ticks.

"In a way, opossums are the unsung heroes in the Lyme Disease epidemic."

Rick Ostfeld, author of a book on Lyme disease ecology and a senior scientist at the Cary Institute of Ecosystem Studies, explains...

"Because many ticks try to feed on opossums and few of them survive the experience. Opossums are extraordinarily good groomers it turns out – we never would have thought that ahead of time – but they kill the vast majority – more than 95% percent of the ticks that try to feed on them. So these opossums are walking around the forest floor, hoovering up ticks right and left, killing over 90% of these things, and so they are really protecting our health."

So it's in our best interest to have opossum neighbors. This means keeping their habitat intact with thoughtful land use planning, tolerating them in our yards, and, whenever possible, avoiding opossum collisions.