Carl Zimmer in Popular Mechanics:
One morning in November 2011, trucks were roaring down the Pan-American Highway, carrying loads of ore from mines in the Atacama Desert to the port town of Caldera, Chile. The trucks screamed past a young goateed American paleontologist named Nicholas Pyenson, who was standing at the side of the road, gazing at a 250-meter-long strip of sandstone that construction workers had cleared in preparation for building new lanes.
Pyenson, the curator of fossil marine mammals at the Smithsonian Institution, spends much of his time searching for fossils of whales. For over a year his Chilean colleague Mario Suárez had been nagging him to come to see whale fossils that had been exposed as construction workers widened the highway. Pyenson envisioned a few skull fragments wedged in a road cut—a very low priority. After completing his work at another fossil site in Chile, Pyenson finally agreed to go see the remains. And standing by the highway, he realized why Suárez had been so insistent. The road crew had uncovered not just a few whale bones but an entire whale graveyard. At least 40 prehistoric whales, some 30 feet long, were spread out before him. It would turn out to be the densest collection of fossil whales discovered anywhere in the world.
Whales may be some of the most remarkable animals in the history of life—they evolved, after all, from deerlike mammals on land and became top predators of the sea. But their fossils can be a nightmare for paleontologists. “I wouldn't wish a whale fossil on anyone,” Pyenson says. “Especially not 40.”