Beards are an example of sexual dimorphism in humans. They a

Beards are an example of sexual dimorphism in humans. They are often viewed as a sign of masculinity as growth is triggered by elevated levels of testosterone. Some have argued that the development of the beard in human males is a result of intrasexual competition and may be a costly sign of male competitiveness. Develop a hypothesis for why human males have evolved beards and provide evidence as to why this trait may be advantageous and may increase fitness.