BY TOM GILLESPIE

Special to The Pilot

The arrival of two baby Hamadryas baboons this past summer at the North Carolina Zoo has added a significant boost to the captive population of this threatened species.

With a troop of 19 - including adults, juveniles and infants - the Hamadryas baboons (Papio hamadryas) at the N.C. Zoo represent not only one of the park's largest species, in terms of numbers, but also the largest collection of baboons in any accredited zoo in the United States.

The N.C. Zoo is the nation's only accredited institution now actively breeding baboons, and the park's troop of 19 forms the majority of the total of 61 baboons currently in institutions recognized by the Association of Zoos & Aquariums, the primary accrediting agency.

"It's been really exciting around here with the new (baboon) arrivals," said Kelly Froio, a baboon keeper at the zoo. "The babies are out in the open a lot, and the mothers are really good at keeping the babies close."

It's not unusual to see the babies clinging upside-down to the mother's stomach area as she walks around the exhibit.

Unlike apes, baboons have tails - the family name means "tailed ape" - and unlike New World monkeys, their tails are not prehensile, that is, not adapted for grasping or holding objects. Considered quadrupeds, they walk more on all fours than any other monkey.

In the wild, their range extends from the Red Sea in Egypt to Ethiopia and Somalia in Africa's Eastern horn. They are also found on the Arabian Peninsula, but it is uncertain if they were introduced by humans or occur there naturally. Within these areas, they prefer to live in semi-desert areas, savannahs and rocky areas that allow cliffs for sleeping.

Baboons form close-knit groups, interacting with each other much more frequently than with the baboons from other families. Within their social structures, the most basic formation is the one-male unit (OMU), typically made up of one male, two to five females that make up the male's harem and all their young offspring. OMUs form clans, then bands; several bands will form a troop. Bands can have as many as 60 baboons, and troops can contain as many as 200.

A typical sheltered sleeping site on a cliff face may be shared by as many as 800 individuals from several troops.

Like many of the other primates, baboons have a complex social structure. Within their social hierarchy, the female with the highest status resides closest to the male. During the day, the females spend much time grooming the group's male and compete for status with him.

Although males will sometimes forcefully steal females from other bands, they will not steal from their own family, but instead, gradually win over a young female without confrontation. Young males inherit females from their father. If a female does not favor her dominate male, she is much more likely to be "stolen" from her male.

Humans and the loss of habitat represent the baboon's main threats since its natural enemies - leopards and lions - have been nearly exterminated in their range. In parts of Africa, baboons are considered vermin that destroy crops and are hunted and killed.

Hamadryas baboons are omnivorous (eating both plant and animal matter) and are not discriminating in their search for food, eating anything from grasses and roots to insects and small vertebrates.

Baboons were considered sacred to the ancient Egyptians and were mummified, entombed and associated with sun-worship. They were often pictured on temples and monoliths as an emblem of the Egyptian god Thoth, who was sometimes depicted either as a man with the head of a baboon or as a squatting baboon. An old Egyptian book shows baboons guarding the gates through which they believed humans pass in order to be reborn.

Visitors can view the zoo's troop of 19 baboons at the Africa Pavilion indoor and outdoor exhibits.

Tom Gillespie works for the public affairs office of the N.C. Zoo.