Monogamous species may go extinct more easily than polygamous ones

Brussels, 09 Jul 2003

A new study has found that monogamy may be proving a fatal attraction for endangered mammalian species. Research Headlines examines the ecological ramifications.

A new study carried out in Ghanaian nature reserves is the first to have found a possible link between mating behaviour and extinction. Conducted by Canada's University of British Columbia, it found that a species' sex life was the second most important influence on its survival after its degree of geographical isolation.

"In avoiding extinction, it pays to be promiscuous," Justin Brashares, the ecologist who carried out the study, was quoted as saying. The Canadian scientist analysed the population records of six reserves in Ghana over the past three decades. In that time, nearly 80 species became extinct, mainly due to hunting and loss of habitat. He found that animals in which a few males monopolise all the females, such as buffalos, green monkeys and baboons, were thriving. On the other hand, monogamous animals, such as the dikdik (a tiny antelope), were in decline. "Many species that we assumed we didn't need to worry about are getting hammered as a result of their behaviour," Brashares says.

Surviving the death of a loved one

It is unclear why sticking to one partner might put a species at risk. It might be because an individual animal might not find a spare partner if its mate has died. Alternatively, it could be because the small groups that characterise many monogamous species are easier for hunters and predators to sneak up on.

Before anyone decides that flirting is the only way to save the human race, biologists point out that monogamy usually exists for a reason. Single partner animals often parent offspring that require a lot of care and attention to survive, or they live in areas where food is scarce.

If, as this survey suggests, mating behaviour is linked to survival, ecologists may have to change their conservation priorities, which tend to focus on large, eye-catching species such as buffalo. These animals are perceived as more vulnerable because they often breed more slowly and need more land.

More work undoubtedly needs to be done to gain a better understanding of the link between behaviour and extinction in order to help conservationists around the world target their limited resources at the most vulnerable species. The EU's Sixth Framework Programme supports research activities aimed at understanding and protecting, in particular, Europe's fragile biodiversity. This was also the subject of a 'Research in action' leaflet produced last year entitled 'Biodiversity in Europe: Understanding and protecting European habitats and oceans'.

DG Research
http://europa.eu.int/comm/dgs/research/i ndex_en.html
http://europa.eu.int/comm/research/headl ines/index_en.cfm