The weightlifter #11

Males disperse away from their natal range to prevent inbreeding and become sexually mature at around 15 years of age. Between 18 and 20 years old they grow much larger and develop secondary sexual characteristics of cheek flanges and a large throat sac, which they use to make booming ‘long calls’ to attract females and warn-off other males. Males compete to become dominant, although non-dominant males do father a large proportion of infants, particularly unflanged males aged 15 to 20 who have not attained full size and can forcefully mate females.