Among most social mammals, males who choose to stay in the group have fewer offspring than those who venture out in search of new horizons. They are the losers of nature, the ones who lose the jackpot of spreading their genes to the fullest because of their lack of courage or strength.
But there is an animal in which this does not work like this: the spotted hyenas ( Crocuta crocuta ). Males of this species that remain in the heat of the herd reproduce as much as those that set out in search of unknown females , according to scientists at the Leibniz Institute for Wildlife and Zoo Research (IZW) in Berlin.
Spotted hyenas form matriarchal societies, with females in command . They usually spend their entire lives within the clan, but males face a crossroads when they reach two and a half years of age: stay or go in search of a new group.
It is a decision that has pros and cons : taking refuge in the heat of the known implies that the young gallant can take the first place among the males and that he will receive the help of his mother, but it will reduce the number of potential partners , because many will be related to him and will reject him for that reason. Joining a new clan might give access to more females – and better quality – but it means that one starts from the lowest rung and will have to spend years fighting to earn the right to reproduce .
IZW scientists have followed 254 male spotted hyenas from eight clans around the Ngorongoro crater in Tanzania for 20 years. When these specimens reached sexual maturity, they left their groups in search of new horizons: 41 returned home, and 213 settled with other herds.
Those who returned home had as many offspring as the nomads , tended to reproduce earlier, and mostly joined females of higher rank than the migrants. Also, their life expectancy was similar.
So, after all, staying with mom isn’t so bad if you’re a male spotted hyena.
