For Immediate Release The Field Museum, Greg Borzo (312) 665-7106 gborzo@fieldmuseum.org Broad, far reaching research Long, thick manes such as this one intimidate rivals and attract potential mates. But they come with a cost, including heat retention. New research shows that lions adapt to hotter climates by growing manes that are less long and thick. This lion lives at the relatively northern Topeka Zoological Park in Topeka, Kansas. Therefore it has a bigger, denser mane than other lions in the study that live in relatively hotter southern climates. The new study examined mane variation for 19 lions in 17 zoos across the United States, from as far north as Chicago to as far south as Houston. Dr. Patterson visited these and other zoos last spring to inspect lions and photograph their manes for later analysis and comparison. His team identified 11 mane fields: throat, forehead, upper neck, sideburns, chest, shoulders, sternum, ribs, belly, elbows and dorsal crest. Dr. Patterson photographed all of these fields for each lion. Later, trained volunteers used the high-resolution photographs to rank the length, density and color of all 11 fields for each lion. The lions ranged from 1.7 to 18 years old, but age did not turn out to be a factor in mane length or density. The zoos included in the study are located in cities that span 12 degrees of latitude or more than 2,000 miles: Alexandria, La.; Coal Valley, Ill.; Dallas; Des Moines, Iowa; Houston; Lufkin, Texas; Memphis, Tenn.; Monroe, La.; New Orleans; Oakland, Calif.; Peoria, Ill.; Sacramento, Calif.; Salina, Kan; St. Louis; Topeka, Kan.; Tyler, Texas; and Vallejo, Calif. Mean temperatures there varied from 20 to 54 degrees Fahrenheit in January and from 65 to 87 degrees Fahrenheit in July. Cold January temperatures showed a stronger correlation with mane variation than did hot July temperatures, suggesting a stronger response to cold than to heat. The volunteers who ranked the lion manes for length, density and color were experienced with observing lions. Most of them had studied lions in Kenya as Earthwatch Institute volunteers. Earthwatch engages people worldwide in scientific field research and education to promote the understanding and action necessary for a sustainable environment. It offers 130 expeditions in 47 countries per year (see www.earthwatch.org). “To date, 300 volunteers from 20 nations have contributed to our work in Tsavo,” Patterson said. Shaking up the lion family tree Based on the results of this study, scientists now know that lion manes can vary tremendously due to local climate. Therefore, taxonomists may be obliged to reanalyze the lion family tree. Over the years, scientists have ascribed lions to various species and subspecies based largely on their outward appearance, especially the length and density of their manes. In fact, 23 different names have been proposed for African Panthera leo. But the new research suggests this number may be exaggerated, an idea that is supported by recent genetic studies. “It is reasonable to hypothesize that most regional variation in manes reflects climate and other environmental influences, such as rainfall, rather than demarcating evolutionarily significant units within Panthera leo,” the authors conclude. Continue>>