People may feel especially drawn to chimps because of some similar

behaviors. Young chimps laugh when they're tickled. Bonobos quarrel over

food, but hug and kiss to make up.

BONOBO: WORKSHOP IN CONSERVATION

The bonobo or pygmy chimpanzee, is one of only four living species of

great apes. The other three species, the gorilla, orangutan, and common

chimpanzee, have received far greater attention until now. Not even

recognized as a separate species until 1929, the bonobo still remains much

of a mystery in its native habitat, the central rain forests of Zaire.

Often confused with the common chimpanzee, the bonobo is only slightly

smaller but has a more graceful, slender body; the head is smaller but the

legs are longer than those of common chimps. The most outstanding physical

difference is the bonobo's hairstyle, an attractive coiffure of long black

hairs neatly parted down the middle. To the experienced eye, the difference

between the chimpanzee and the bonobo is as great as the difference between

a leopard and a cheetah.

The bonobo is as rare in zoos (there are less than 80 in captivity

worldwide) as it is in the wild (estimates range from 5,000 to 20,000). In

1989, the entire San Diego Zoo group of 11 animals was relocated to the

Wild Animal Park.

No effective conservation plan for the bonobo could be developed

without firsthand knowledge of the only country that is home to this

critically endangered ape. International conservation projects are as much

a people issue as an animal issue; therefore, the needs of the local

Zairian people must be taken into account. Political, cultural, and

economic problems are just as important to consider as the biological needs

of the species we are attempting to save. For these reasons, the San Diego

Bonobo Workshop continually emphasizes the need for an international

cooperative effort with the people and government of Zaire.

In light of the increasing awareness of the need to preserve the

world's biodiversity, it is quite surprising how little attention Zaire has

received. The extent and variety of the biological resources in Zaire's

forest ecosystems is matched by few other tropical countries. After Brazil,

Zaire has the second largest tropical forest in the world. Despite this

fact, Zaire is among the last of the countries in the tropical forest belt

without a comprehensive program to protect its tropical forest. Programs

like the one developed at the San Diego Bonobo Workshop will be

instrumental in obtaining funds from organizations like the World Bank to

protect the bonobo and its forest habitat.

THE GORILLA SUBSPECIES

Three subspecies of gorillas are currently recognized. Almost all zoo

gorillas are western lowland gorilla (Gorilla gorilla) native to west

African nations such as Cameroon, the Central African Republic, Gabon,

Nigeria, and Rio Muni. The total population of western lowland gorillas is

estimated to be between 30,000 to 50,000 individuals, and they are

classified as threatened by the IUCN (International Union for Conservation

of Nature and Natural Resources). Studying these gorillas in the wild is

extremely difficult, because their preferred habitat is dense jungle.

A very few eastern lowland gorillas (Gorilla gorilla graueri) native

to eastern Zaire, live in zoos. Mbongo and Ngagi, the two "mountain

gorillas" who lived at the San Diego Zoo in the 1930s and 1940s, would now

be classified as eastern lowland gorillas. These gorillas are considered

the largest subspecies on average, and generally have blacker hair than

western lowland gorillas. They number approximately 3,000 to 4,000 and are

classified as endangered.

No mountain gorillas (Gorilla gorilla beringei) exist in captivity,

but these are the most-studied gorillas in the wild. They live in the

mountainous border regions of Rwanda, Uganda, and Zaire. Only about 600

individuals exist, in two separate populations, and they are classified as

endangered. Mountain gorillas are distinguished physically by their large

size and extra-long, silky black hair. A number of skeletal differences

exist between the three subspecies as well.

It would be interesting to see if DNA sequence comparisons could help

us understand the phylogenetic (evolution of a genetically related group as

distinguished from the development of the individual organism)

relationships of the gorilla subspecies. This could help anthropologists

understand the mechanisms and rates of primate evolution. It could also be

important if gorilla populations ever become so critically depleted that

interbreeding of different subspecies were contemplated. At CRES, we are

comparing DNA sequences from gorillas of all three subspecies. Only a few

gorillas have been tested so far, but to date it appears that the

relationships between the subspecies generally follows the geographic

location of populations.

Western lowland gorillas have a large range, and many DNA sequence

differences exist between different individuals of this subspecies. Western

lowland gorillas are separated by 600 miles from eastern lowland gorillas,

and substantial sequence differences exist between the two groups as well.

The eastern lowland and mountain gorilla populations are found relatively

close together, but they have been isolated from each other for an unknown

amount of time. They are presently separated by substantial geographic

barriers: portions of the Rift Valley and a variety of mountain ranges.

However, we find much less genetic difference between the eastern lowland

gorillas and the mountain gorillas than there is between certain western

lowland gorillas. The distinct physical differences between eastern lowland

and mountain gorillas probably reflect recent adaptations to their

respective habitats -- lowlands versus mountains -- and not a distant

genetic relationship.

LION-TAILED MACAQUES: BACKGROUND

The macaques, a genus of some 13 to 20 species (there is disagreement

among taxonomists on the actual number), are found in North Africa and

throughout southern Asia from Afghanistan to Japan. The most familiar form

is the rhesus monkey, which is often seen by tourists in the towns and

cities of India. Fossils dating to six million years indicate that the

macaques originated in northern Africa and once roamed over Europe as far

north as London. These earlier macaques were not very different in

appearance from the Barbary monkeys that survive today in Morocco, Algeria,

and on Gibraltar. However, once the Macaques reached Asia, at least by

three million years ago, they diversified into a variety of forms. Few are

as distinctly different as the lion-tails, with their black coats, silver

facial ruffs, and strongly arboreal habitats. Lion-tails are one of the two

macaque species that are listed as in danger of extinction, but we may

realistically expect the Tibetan, Formosan, and Sulawesian species to fall

into that category before the year 2000.

Their geographical range snakes along the slope's and highest crests

of the Western Ghat Mountains where, today, the forest is reduced to about

one percent of the total land cover. Like its captive counterpart, the wild

living lion-tail was ignored by primatologists until well into the 1970s.

Although opinions vary, most would agree that the wild population today

numbers between 2,000 and 5,000 individuals. Initial field reports indicate

that wild lion-tails prefer to spend about 99 percent of their time in the

trees. Like other macaques, their diet is dominated by wild fruits, but

includes a variety of flowers, leaves, buds, grasses, insects, and even a

few nestlings of birds and mammals. One of the more interesting forms of

feeding reported by Dr. Steven Green of Miami University involves a simple

form of tool use. In order to protect their hands while feeding on stinging

caterpillars, lion-tails have been seen to pluck large tree leaves and lay

them over the caterpillars before pouncing on them.

In the wild state, lion-tail groups average about 20 individuals,

usually with more than a single adult male present. Males are larger than

females by about a third and are typically ranked relative to one another

in a social hierarchy. Males usually emigrate from their natal group to

join another during the early stages of adulthood. Being macaques, lion-

tails are intensely social and are highly aggressive toward unfamiliar

individuals. Preliminary work on our captive population indicates that much

of the behavior between group members is dependent upon one's relationship

to a small number of female-headed lineages. It is possible to have up to

four living generations within each matriline and four or five matrilines

within a group. Dominance relationships among and within matrilines play a

crucial role in the everyday life of females and their offspring, as they

do for adult males. One's social position determines access to essential

resources such as food, perches, and social partners.

LION-TAILED MACAQUES: FUTURE PLANS

This highly endangered primate has been exhibited at the San Diego Zoo

since 1923. In 1979, the existing population of three males and three

females was relocated to the Primate Research Pad for concentrated study of

their reproductive biology. Within the next decade their reproductive

cycles were characterized, as were their sexual and social behavior,

parturition and infant rearing, and various other aspects of the captive

experience. Nearly a dozen scientific papers from these studies have been

published in peer-reviewed journals or as book chapters.

BY 1989 the Zoo's captive population had grown to 38 individuals. This

same year the program undertook a significant change in direction. Seven

individuals, including five born at the Primate Research Pad, were released

into a state-of-the-art exhibit in Sun Bear Forest. Although these

individuals are no longer under study, it was knowledge gained over the

previous decade that contributed to the design of an exhibit facility

which, by anyone's criteria, is an outstanding success.

A second troop of 11 individuals was simultaneously relocated to the

newly constructed 3/4-acre breeding kraal at the Wild Animal Park. It is

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