The Surprising Truth About Turtles: Evolution and Adaptation

Introduction: Rethinking the Turtle

Almost everyone has seen a turtle — and not just the pizza-eating Teenage Mutant Ninja variety. Many people keep small turtles as pets, both indoors in terrariums or tanks and, with some varieties, outdoors in gardens and backyards. Larger turtles live in zoos and, to an ever-diminishing extent, in the world's oceans and on land. Lumbering and slow, it is perhaps surprising that the turtle has survived across the eons despite seeming so ill-adapted to the pace of life and the pressures of predation. Their famed shells do offer a substantial measure of protection, of course, but that alone hardly seems to counteract their apparent inability to fend off a predator or forage efficiently for food. Though it was a tortoise — a close relative of the turtle — that famously beat the hare through slow and steady persistence, turtles are generally associated with laziness and cowardice by today's hustle-and-bustle world. What follows might surprise you.

Turtles have remained largely unchanged across vast stretches of evolutionary time not because they are lazy or cowardly, but because they are among the most industrious, well-adapted, and efficient creatures nature has ever produced. The slow movement of turtles on land is directly related to the development of their shells, in a complex evolutionary relationship of inheritance and divergence (Rieppel and Reisz 13–15). At the same time, though all turtles share these twin peculiarities that invite so much figurative derision, individual turtle species have adapted to fill very specific ecological niches, combining unique traits and remarkable intelligence with one of the most efficient and complete security systems nature has ever developed (Pitman 194; Luschi et al. 528).

Turtle Diversity and the Tortoise Distinction

The first truly remarkable thing about turtles is the sheer number of species that exist, all descended from the same common evolutionary ancestors and sharing the same peculiar features unique to turtles (Rieppel and Reisz). There are species of turtle that, fully grown, could still sit easily on an adult's hand, and others that weigh hundreds of pounds and would crush any person who tried to hold one single-handedly — or even double-handedly, for that matter. The creature most people tend to picture when they think of a turtle — the slow, plodding animal on a dusty road — is actually a tortoise. Though tortoises are related to turtles, they are certainly not the same thing. Turtles do not last long on dry, dusty roads; they need water, and many species live in aquatic environments almost exclusively.

Catching Turtles: A Field Perspective

Ponds and the wide, still stretches along rivers are popular places to go looking for turtles. A self-proclaimed turtle expert who estimates he has caught over a hundred turtles over the years — both to keep and to sell as pets — explains that the key is knowing where to wait and being able to do so patiently. "First," he says, "the trick is knowing where to wait and being able to do it. The rest is easy." He may be making it sound somewhat easier than it really is, but he is certainly right about the waiting. Turtles are notoriously shy creatures; they can withdraw so easily that coaxing them out of their shells — pun intended — is a genuine challenge. If you can remain still enough with the proper bait placed near the water's edge, however, and if you are lucky and patient enough, a turtle might just come your way.

Conclusion: The Case for Turtle Conservation

Rieppel, Olivier, and Robert R. Reisz. "The Origin and Early Evolution of Turtles." Annual Review of Ecology and Systematics 30 (1999): 1–22.