Book ReviewLifestyleVOLUME 18 ISSUE # 25

New discoveries are bringing the world of pterosaurs to life

In an eat-or-be-eaten world, flight conveys a bevy of benefits. A creature that takes to the third dimension can more easily escape earthbound predators, dine off a much broader menu or drop down on unsuspecting victims from above. Flying also allows an animal to cover distance more quickly, forage more efficiently and find mates more easily.

So it’s perhaps surprising that only three groups of vertebrates have ever evolved sustained, muscle-powered flight. Pterosaurs, Greek for “wing lizards,” arrived on the scene in the Triassic Period, perhaps as early as around 237 million years ago. These original vertebrate fliers preceded birds by at least 70 million years and bats by more than twice that.

What caused pterosaurs’ demise is clear: The same asteroid that wiped out the non-avian dinosaurs about 66 million years ago also took them out — along with more than 75 percent of all life on Earth. But how pterosaurs took to the air in the first place remains a big mystery. “We don’t have any properly transitional fossils for pterosaurs, or at least ones that we recognize,” says Matthew Baron, a freelance vertebrate paleontologist.

Despite the gap in the early fossil record, recent research offers clues to who pterosaurs’ earliest cousins were and what they looked like, and how pterosaurs evolved from small, flitting creatures into an incredibly varied group. They eventually occupied ecosystems worldwide and consumed a wide variety of prey — getting bigger and spreading farther earlier than previously thought, recent studies reveal. Some grew bizarre crests atop their heads, while others sported mouths full of teeth that projected threateningly at various angles.

“Some pterosaurs looked like creatures from your nightmares,” says Brian Andres, a vertebrate paleontologist at the University of Sheffield in England. During their lengthy reign of the skies, pterosaurs ranged in size from creatures that could sit in the palm of your hand to soaring behemoths with wingspans that rivaled those of an F-16 fighter jet. In fact, the largest animal that ever took flight — an iconic species discovered more than half a century ago but only recently described in great detail — was a pterosaur.

Pterosaur fossils were first unearthed in the late 1700s — coincidentally, from the same limestone formation in Germany that later yielded the earliest known bird, Archaeopteryx. Scientists didn’t quite know what to make of the fossils. One scientist proposed they belonged to a weird sea creature, and another thought they represented a transitional form between birds and bats. But soon, experts settled on the fact that pterosaurs were flying reptiles, distinct from dinosaurs.