Excavations in a clay pit in southwestern Germany have yielded two tiny treasures. They’re the first fossils of hummingbirds from the Old World and, by far, the oldest ones unearthed anywhere.
Hummingbirds are the only birds that can fly forward, backward, and sideways, as well as hover for sustained periods. Those aeronautical talents, along with long bills and even longer tongues, enable the avian acrobats to drink nectar from small, tubular flowers. Although there are more than 300 living hummingbird species, these birds are found only in North and South America, says Gerald Mayr, an ornithologist at the Senckenberg Research Institute in Frankfurt, Germany.
The two new specimens, unearthed from deposits with fish and plants that date to between 34 million and 30 million years ago, have major wing bones that are short and stocky, like those of living hummingbirds. Aptly named by Mayr as Eurotrochilus inexpectatus, which translates as “unexpected European version of a hummingbird,” the newly identified species had a long, narrow bill that was more than twice as long as its skull. This characteristic, as well as others related to the creature’s wing structure, suggests that the birds hovered and drank nectar just as their latter-day relatives do. Mayr describes the ancient species in the May 7 Science.
Previously, the oldest fossils of hummingbirds were 1-million-year-old specimens recovered from cave deposits in Central America.
The new fossil find raises the question of why hummingbirds went extinct in the Old World. That group of continents—Europe, Asia, and Africa—had no geographic barriers that would have prevented the birds from spreading far and wide, says Mayr. Indeed, in the Western Hemisphere, hummingbird ranges include Alaska and Tierra del Fuego, and the birds forage in habitats as diverse as tropical lowlands and 4,500-meter-high slopes of the Andes.
Despite the previous absence of evidence and the lack of current hummingbird inhabitants, some scientists had suggested that hummingbirds once populated the Old World. Several species of plants there, especially in parts of eastern Africa and the Himalayas, sport flowers that appear to be adapted to hovering avian pollinators.
Mayr’s find has “fascinating implications,” says Ethan J. Temeles, an evolutionary ecologist at Amherst (Mass.) College. For instance, he notes, the shape of those enigmatic Old World blossoms—which are now pollinated by appropriately equipped insects, such as long-tongued bees—may originally have evolved to match the bill shape of ancient hummingbirds.