The Big Question

Which animal has most changed the course of history?

Graham Roumieu

Jack Hanna, host, Jack Hanna’s Wild Countdown, and director emeritus, Columbus Zoo and Aquarium

Colo, the first gorilla born into human care, in 1956 at the Columbus Zoo in Ohio, and now the oldest gorilla on record. Colo and her descendants have paved the way for successful breeding programs and innovative advancements in animal care. We’re still learning from her today.

Jamie Shreeve, executive science editor, National Geographic

The mockingbirds collected in the Galápagos archipelago in 1835 by a young naturalist, who marveled at the subtle variations among specimens taken from adjacent islands. Could the varieties have diverged from a single common ancestor? “Such facts would undermine the stability of Species,” Charles Darwin wrote in his journal. Many more facts had to be synthesized to complete the undermining, but when it was finished, God was no longer required to explain creation.

Donald Johanson, paleoanthropologist

Lucy surfaced in Ethiopia 40 years ago, some 3.2 million years after her death—an upright walking ancestor, part ape and part human. She launched a golden age in the study of human origins that led to the conclusion that all living people share an African ancestry.

Jack Cover, general curator, National Aquarium

Martha, the last known passenger pigeon, died at the Cincinnati Zoo on September 1, 1914, bringing the existence of her species to an end. Her death provided irrefutable evidence that even the most abundant species can be driven to extinction, and inspired the passage of numerous wildlife-protection laws.

Susan Orlean, author, Rin Tin Tin

Its name was probably just a variant of a caveman grunt, but whichever wolf was the first to slink up to a Paleolithic-era campfire and wag its tail, offering to befriend the humans there rather than eat them. Domesticating animals changed everything: it made us farmers rather than hunters, allowed faster travel, and provided the muscle power to move huge things—and, of course, gave us a whole new set of friends.

David W. Anthony, author, The Horse, the Wheel, and Language

The power of modern engines is measured in horsepower for a good reason. Domesticated on the Eurasian steppes before 3500 B.C., horses carried the Huns, the Mongols, and the Pizarro brothers to victory over the Romans, the Chinese, and the Incas, remaking ancient cultures into societies dependent on high-speed mobility, and revolutionizing human transport.

Marc Bekoff, author, Why Dogs Hump and Bees Get Depressed

Earthworms are vital to the integrity of a wide variety of ecosystems on which humans depend. In The Formation of Vegetable Mould, Charles Darwin noted, “It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organised creatures.”

Jill D. Pruetz, biological anthropologist

David Greybeard, the male chimpanzee in Gombe, Tanzania, who first trusted Jane Goodall in her efforts to habituate wild apes to her presence. He changed the way we defined our own species after Goodall observed that he made and used a tool, a trait that at the time we thought our species alone possessed.

Stephen Suomi, chief of the laboratory of comparative ethology, National Institutes of Health

Throughout history, rats have been key vectors in spreading pestilence among humans around the world. However, laboratory rats have been key to countless advances in basic biomedical knowledge and medical practice, ultimately improving human longevity and well-being in once-unimaginable ways. Causing massive death, improving life for billions—that’s a real twofer!

Irene M. Pepperberg, author, Alex and Me

Whether you accept it to be the comb jelly or the sponge (or whatever critter on which this moniker will eventually be bestowed), the first animal to emerge is the ancestor of all those that exist today. Without that species, there would be no others to discuss!