My friend eats bugs for breakfast

I carried my pet Venus Fly Trap outside to an anthill for breakfast this morning, and as I watched it feast upon the little beasts, I got to thinking about evolution again.

The fly trap is the most famous of carnivorous plants, but it's not the only one. Sundews catch bugs with sticky droplets, kind of the way little kids trap germs on their grubby paws. Pitcher plants have perfected the art of drowning their prey inside slender vases full of flesh-dissolving enzymes.

These plants all grow in swamps, where the soil is poor and the protein of a bug is a great benefit.

It's easy to see how a pitcher could have evolved from some of the tubular contraptions that some other plants make. Or how some early sundew could have produced its sticky goo in the way that other plants do, such as a catch-fly flower, which hasn't learned to make use of it for making bugs into breakfast.

But, as I posted a while ago about the mosquito, the Venus Fly Trap is another one of those living things that appears to be an evolutionary mystery to me. The whole complicated structure has to work perfectly or the plant gets no meal. Sensitive hairs have to be touched just right by a crawling bug in order to trigger the snap-shut reflex. The leaf has to close completely or the bug will squeeze out and be gone. Then the leaf-trap has to secrete enzymes to digest the bug or the whole scenario is for nothing.

There are plants in the world that close at a touch -- such as a little clover-like thing that grew in the lawn when I lived in Hawaii years ago. So maybe one of those accidentally trapped a bug now and then and thrived on the unexpected protein, becoming more specialized over the eons.

With the world so full of bugs, one might think that Venus Fly Traps would be everywhere. But, surprisingly, they grow only on the East Coast of the U.S., within a few swamps.