Why do the top dogs get the pretty ladies?

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A story of sex, stress and hyena poops

By Eve Davidian

In most animal societies, resources are not shared equally among members of a group. Those at the top of the social hierarchy eat the tastiest food, get the comfiest sleeping spots, and can hang out – and more if they hit it off – with the most attractive and fecund mates. In the animal world, where lifetime achievement is largely determined by the number of offspring one leaves behind, it is rather straightforward why individuals should work hard to reach the top and try to remain there for as long as they can.

What we still don’t quite understand is how social rank influences reproductive success. Do high-ranking males sire more offspring and offspring of higher quality because they are stronger and more attractive? Or is it because they are less “stressed” by competition with other males and can invest more in courting females?

To answer these questions, we did fieldwork in the African savannah. Lots of fieldwork. Over 20 years of searching, identifying, assessing paternities, and monitoring the behaviour of thousands of free-ranging spotted hyenas in the Ngorongoro Crater in Northern Tanzania. We also collected over 400 steaming hyena scats to measure the concentration of cortisol, an estimate of the physiological costs – or so-called “stress” – borne by a hyena. [To know what it takes to be a hyena poop hunter click on the poopers below.]

Our new study published in the journal Functional Ecology demonstrates that interactions with other males are more stressful for low-ranking males than for their high-ranking rivals and that this restricts the time and energy they can invest in courting the most fecund – and most contested – females. We also found that males have to juggle romance and more mundane duties like getting acquainted with new clan mates and maintaining old friendships and strategic alliances.

But low-ranking males shy away from these stressful activities and spend more time away from other clan members, munching on bones or chilling in stinky puddles. High-ranking males, on the other hand, need less time on their own to detox and destress, and can invest a lot more in fostering friendly relationships with females. And that’s something hyena females are very much into!

In contrast to many species where males use their physical strength, long horns and sharp teeth to deter rivals – or even to sexually coerce females – male spotted hyenas do not engage in violent fights to get to the top of the hierarchy and to sire offspring [males couldn’t coerce females even if they wanted to because female genitals are masculinized into a rape-proof device]. Why then are low-ranking males more stressed out than high-ranking males?

Male hyenas may not be ruthless brutes but they are no peaceful hippies either. Dominance relationships in hyena society are primarily determined by how many social allies a hyena can count on when in conflict with others. Low-ranking males usually are newcomers and lack strong alliances. They are also more vulnerable to being used as scapegoats by others and this is likely to be a major source of stress. Scapegoating is frequent among hyenas (and other animals) and likely serves as a means to release frustration and cope with stress. In hyenas, it often takes the form of a chain of dominance whereby successive males redirect aggression onto another, lower-ranking male. And when the lowest-ranking male of such a chain has no scapegoat nearby, rushing tail up at an innocent jackal, a rock, or even our research vehicle seems to do the job.

But don’t feel too sorry for low-ranking males. Their time will come. The social rank of male spotted hyenas is determined by a queuing convention. Most males eventually climb the social ladder and get to enjoy the perks of being the top dog.

Original publication:

Davidian E, Wachter B, Heckmann I, Dehnhard M, Hofer H, Höner OP (2020) The interplay between social rank, physiological constraints and investment in courtship in male spotted hyenas. Functional Ecology


Further information

Davidian E, Courtiol A, Wachter B, Hofer H, Höner OP (2016) Why do some males choose to breed at home when most other males disperse? Science Advances 2 e1501236.

Höner OP, Wachter B, East ML, Streich WJ, Wilhelm K, Burke T, Hofer H (2007) Female mate-choice drives the evolution of male-biased dispersal in a social mammal. Nature 448: 798-801.

Davidian E*, Benhaiem S*, Courtiol A, Hofer H, Höner OP, Dehnhard M (2015) Determining hormone metabolite concentrations when enzyme immunoassay accuracy varies over time. Methods in Ecology and Evolution 6(5):576-583. *contributed equally


It’s tough to be a male in love

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By Eve Davidian

Spotted hyena males can be very persistent when they have a crush on a female. They may follow the female’s every movement: lie down a few meters away from her when she decides to rest, observe her when she changes her position or lifts her head, and get up and follow her when she walks away – in human society, such a behavior would be considered as stalking. In spotted hyenas, males use this rather exhausting strategy to foster and maintain a friendly relationship with the female – and more if they hit it off. Staying nearby a female also allows the male to displace rivals if they come too close to their loved one or to defend the female if she is being aggressively harassed by another male – harassment by males occurs regularly but is a far less successful strategy than a charming courtship.

There was a period when Kondo, one of the males in the Ngoitokitok clan, was very much into the female Aiba and was following her wherever she went. Aiba seemed ok with this rather old guy sticking around. They actually made quite a cute couple sleeping close to each other. One day, as we were approaching them by car, Aiba got up and walked away from her resting place – and from Kondo. Kondo was then deep asleep and did not react to her departure. When he woke up 15 minutes later, yawning and stretching his legs, he immediately checked the place where his girlfriend was resting. As soon as he realised that Aiba was gone he jumped up and scrutinised the surroundings to see where she was. But Aiba was nowhere to be found. Kondo looked very nervous indeed; running around and sniffing the ground for cues, pricking his ears up, running again in great excitement. It was obvious that he was desperate to find Aiba again.

We took pity on Kondo and tried to show him the direction Aiba had taken but Kondo was not paying attention. He kept trying to pick up her scent and eventually ran in the wrong direction. Poor Kondo! For more than two weeks, he had bet everything on Aiba and would have to start from scratch with another female if he did not find Aiba quickly. But no worry, when we saw Kondo again three days later he was reunited with his beloved. It seemed that after all Aiba did not resent Kondo for his lack of attention.

Here is what a male looks like when desperately looking for his lost female: