For Immediate Release The Field Museum, Greg Borzo (312) 665-7106 gborzo@fieldmuseum.org Claims to fame The Tsavo lions, which live in the dry, scrubby grasslands of East Africa, represent the only well documented population of maneless lions. They attracted international attention in 1996 with the release of the major motion picture The Ghost and the Darkness, which tells the story of two large Tsavo lions that killed and ate more than 130 railroad workers in 1898. The workers were building a bridge for the British over the Tsavo River in southeastern Kenya when they faced a nine-month “Reign of Terror.” Construction was halted for several months until the lions were hunted down and killed. The two lions were stuffed and are now one of The Field Museum’s most popular displays. Visit the Tsavo Lions website. Ironically, manes are so symbolic of male lions that The Ghost and the Darkness used maned lions to represent the two maneless man-eaters of Tsavo. Scientists believe that lions evolved manes because they attract females, deter trespassers, intimidate nomadic males, give a visual sign of a territorial male’s control, and protect the vital head and neck regions in a fight. Manes serve similar functions as antlers in deer. But with so many advantages, why do Tsavo lions lack manes – something that this research confirmed scientifically for the first time? Some scientists have suggested that male Tsavo lions really do grow manes but that the region’s tangled thorn bushes tear away tufts of hair as the lions hunt and chase their prey. This theory was dispelled by observations of maneless male lions in arid grasslands lacking thorn bush. Some have even suggested that the Tsavo lions are a distinct species, but this possibility is unsubstantiated. The new research, on the other hand, suggests that Tsavo lions have actually evolved to be maneless over many generations. This may be because of the high environmental cost of possessing a mane in the hot, dry Tsavo landscape. In addition, a mane would make it difficult to negotiate the thorns and bramble of Tsavo’s thick undergrowth. Thus, manes might put Tsavo lions at a disadvantage because they would retain heat, cost water, attract potential rivals and scare off prey. “Comparing the ecology and social life of maned and maneless lions should shed light on the evolutionary significance of the mane,” says Kays, curator at the New York State Museum in Albany. Kays was a post-doc at The Field Museum when the research was conducted. Continue