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Range and Habitat: Japan, including Honshu, Shikoku, Kyushu,
and Takeshima Islands. It is the most northerly species of monkeys.
Lives in forested hilly areas.
Habits and Adaptations: Live in troops ranging from 25
to over 500 individuals. Usually one adult male for every four
females. Strict dominance hierarchy. Home range up to 8 sq. km
(3 sq. mi.), sometimes overlapping the ranges of other troops.
Intergroup behavior is also dependent on dominance.
The alpha-male role is to lead. The sub-males follow and keep
discipline within the group. The female role is to produce and
rear young. There is also social ranking among females. A female's
rank determines her offspring's rank within the troup.
Diurnal, they spend time either in trees or on ground. Complex
communication: more than 30 vocal sounds have been recorded; wide
range of facial and body expressions.
Diet: Fruit, roots, leaves, insects, crops such as rice,
maize and potatoes.
Breeding and Maturation: Gestation period of 170-180 days;
almost always single births typically in April or May. Weight
at birth 450-500 g (16-17.5 oz.), nurse about 6 months. Sexually
mature at age 4-5 for males and 3-5 for females. Sometimes males
and females in the troup will care for another mother's young.
Miscellaneous: Extensive studies have revealed highly
complex social structure and excellent learning abilities. Individuals
have been known to invent new behavior patterns which are learned
in time by other members of the troop.
Two subspecies of Macaca fuscata are found on the large southern
islands of Japan, making their range the northernmost of any non-human
primate. Weather conditions there are harsh, with winter temperatures
often falling below freezing and snow accumulating to a depth
of five feet. It is not difficult to understand why snow monkeys
were chosen for display at the MZG.
The macaque is a medium-sized primate with a stout body, strong
limbs, and a very short tail. It spends most of the day gathering
food. The diet is versatile, consisting of a wide variety of plants
and animals. The macaques are long-lived, estimated to live up
to 30 years in the wild. Mating takes place generally in the fall
and winter, with the young being born in April or May.
All animals of a troop know one another and there is definite
social order within each group. For the most part, they live on
the ground - a far more dangerous environment than that of their
tree-dwelling relatives. Consequently, there have been selection
pressures for physical strength, large canine teeth and a well-ordered
social structure.
The most striking feature of social behavior in the troop is
that a few males dominate all the other animals. The top position
in the troop is the leader, or "alpha" male. Immediately
below the alpha male are two or three "subleaders",
followed by most of the adult females, which reach puberty at
three years and full body size at about six to eight years of
age. The infants and juveniles form the middle of the hierarchy,
with the remainder of the adult males at the bottom of the hierarchy.
In the wild, they would live on the periphery of the troop.
It is noted that the dominant male is not at the top of the hierarchy
because of his fighting ability or physical characteristics. It
seems that the rank of each animal is closely correlated with
the rank of its mother. You may see an adult male in the troop
defended by its mother. The role of alpha appears to be one of
directing the movement of the troop, and defending it.
A principal role of the subleaders seems to be stopping fights.
They do this by chasing away the more aggressive macaques. It
is noted that when the alpha male is around, subleader males appear
to be uncertain, and alternately threaten the fighters and turn
to look at the alpha male.
The role of the adult females is to raise their offspring and
protect them. Mothers do not allow other macaques to pick up their
infants for several weeks after birth. Although infants are a
great source of interest to other females.
Juvenile males tend to spend more of their time rough-housing
in play groups than juvenile females do. The females are mostly
occupied with grooming activities with their mothers and sisters.
Macaques are highly intelligent animals, incorporating learned
behavior patterns into the troop's routine activities in a very
short time. One of the more interesting phenomena observed and
reported about a macaque troop is the now famous "sweet potato
washing incident". A scientist, reporting in a 1953 magazine,
recalled a story in which a 1.5 year old female he was observing
picked up a sweet potato which was covered with sand. She dipped
the potato probably by pure accident into the water and rubbed
off the sand with her hands. By this inconspicuous act, she introduced
"monkey culture" to the rest of the troop. Within a
few years, fifteen animals washed their sweet potatoes before
eating them.
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