ThirteenThieves,
Lion manes are obviously a sexually selected trait. Manes are restricted to males, contribute little to the lion's general…
Lion manes are obviously a sexually selected trait. Manes are restricted to males, contribute little to the lion's general…
Like the lion's mane, male humans may have beards to serve as protection in intraspecies fights (psst, Matt Knox): http://www.ncb…