SIMANDLE, E.T.*; TRACY, C.R.; University of Nevada, Reno; University of Nevada, Reno: The Mane Question: Untangling why lions have it

Lions (Panthera leo) are unique among felids, in that most males possess a conspicuous mane. For over a century, researchers have speculated that the lion�s mane may confer certain costs or benefits with respect to male fitness. It is clear that, in some populations, female lions prefer male lions with larger and darker manes, suggesting that there is a fitness advantage to large dark manes. A recent publication suggested that possessing a mane also has a �thermoregulatory cost� and that �Heat appears to be the dominant ecological factor shaping the lion�s mane�. This apparent tradeoff was hailed as one of only a few examples of a physiological cost of a sexually selected trait. I critically examine the major conclusions of this paper and introduce additional evidence that bears on these conclusions. I demonstrate that the majority of the conclusions related to the �thermoregulatory cost� of a mane are tenuous, and in many cases, likely erroneous. Finally, I suggest new approaches that may help to untangle the question of why lions have manes.