Male monkeys ride fathers' reputation to success

Washington, July 11 (IANS) If you're born to a father who's a strong and enduring community leader, you're far more likely to become a leader yourself due to a range of advantages accruing from your dad's position.

The new research led by University of California Los Angeles (UCLA) primatologist Susan Perry, provides a glimpse into how our male ancestors may have jockeyed for power and passed it on to their male offspring.

"Offspring, especially male offspring, raised in a group in which their father is the alpha male, throughout their juvenile phase enjoy a host of advantages over less fortunate monkeys," said Perry, anthropology professor, who has studied capuchins for 22 years.

"A stable, peaceful family environment may have been important to the well-being and future success of children among our remote ancestors, just as it is to children today," added Perry, the journal Advances in the Study of Behaviour reports.

Widely known for their cleverness, dexterity and trainability, capuchins enjoy a distinction that makes them especially compelling to scholars of the evolution of behaviour, according to an UCLA statement.

The cat-sized primates have the largest brain-to-body ratio among non-human primates, making their behavior particularly relevant for understanding the evolutionary history of their big-brained relatives - the humans.

"There are a lot of reasons to suspect that the same selective forces that shaped humans also shaped capuchins, causing both species to share features such as complex political behavior and culturally transmitted social rituals," Perry said.

Since 1990, Perry; her husband, Joseph Manson (also UCLA anthropologist); a University of Iowa faculty member; and 122 students, volunteers and copiously trained locals have spent approximately 79,000 hours observing 444 capuchins that make up 11 social groups in Costa Rica's Lomas Barbudal Biological Reserve.

With data on five generations of these animals, which can live into their 50s, Perry's Lomas Barbudal Monkey Project is the world's most detailed study of any natural primate population. In fact, no other study has so thoroughly documented the details of the lives of so many members of a single species of long-lived mammals.

Perry's latest findings explore the social dynamics of capuchins, who form cooperative groups with an alpha male, several subordinate males and many females. The average size of these groups in the Lomas reserve is 19 monkeys, Perry has found. The alpha males rise to their position - and defend it - by fighting off other males with the help of allies.

Initially, females mate exclusively with the alpha male, Perry said. Extraordinarily, subordinate males wait to mate until the alpha male's daughters reach sexual maturity, a process that takes an average of six years. The regimes of most alpha males last about a year, but regimes at Lomas have lasted for as long as 18 years and for as little as a fraction of a day.

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