杏吧原创

KIDNAPPING amorous males who hold a sexual monopoly over their peers may be
the key to saving some endangered species.

In certain species, the top boys fight to restrict access to females,
preventing subordinate males from mating. This can help pass on qualities such
as strength to the next generation.

But having only a few breeding males has its drawbacks. It also limits
genetic variety in the population, making it more vulnerable to sudden changes
in the environment鈥攅specially if numbers shrink. 鈥淲ith just 200
individuals you鈥檙e really starting to worry about genetic diversity,鈥� says Peter
Tolson from the Toledo Zoo in Ohio.

This has prompted Allison Alberts and colleagues at the San Diego Zoo to
propose a new method of conservation: temporarily kidnapping the dominant males.
Removing them should give other males a shot at reproduction and maximise the
genetic diversity of a population. This would give the population a better
chance of surviving a new disease or a sudden change in climate. 鈥淲hen you
consider the benefit I think it is a feasible strategy,鈥� says Tolson.

The team tested the idea on a population of Cuban iguanas (Cyclura nubila) at
Guant谩namo Bay in Cuba. These iguanas are not endangered, but many of
their sister species are. The researchers removed the five highest-ranking males
for six weeks during the breeding season. Other males quickly seized their
chance and began breeding. When the dominant males were brought back they fought
with the usurpers to regain supremacy.

鈥淭his is very much an emergency measure,鈥� cautions Alberts. The scheme would
be labour intensive and costly. But most of the population would remain in the
wild, sustaining the impetus to conserve the habitat.