is a small island in the
Sea of Hyūga off the shore of the city of
Kushima in
Miyazaki Prefecture
is a Prefectures of Japan, prefecture of Japan located on the island of Kyūshū. Miyazaki Prefecture has a population of 1,028,215 as of 1 January 2025 and has a geographic area of 7,735 Square kilometre, km2 (2,986 sq mi). Miyazaki Prefectur ...
,
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
. The island is approximately 13 km ESE and 20 km by road from the central built-up area of Kushima. It is approximately 300 m offshore and 30
hectare
The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), that is, square metres (), and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. ...
s in area, and mainly forested.
Kōjima is best known as housing a field study site of the Japanese
Primate Research Institute, where
Japanese macaque
The Japanese macaque (''Macaca fuscata''), also known as the snow monkey, is a terrestrial Old World monkey species that is native to Japan. Colloquially, they are referred to as "snow monkeys" because some live in areas where snow covers the g ...
s are held in wild conditions for
primatological study. The buildings of the field station are on the mainland so as to minimise disturbance of the monkeys' behaviour. Study of the monkeys began in 1947, and since 1952 all individuals have been marked so that the demographics of the population can be studied. Many investigations have been carried out, including studies of the changes that occur in social
dominance over time. Kōjima is the site of one of the best-known studies in
animal culture
Animal culture can be defined as the ability of non-human animals to learn and transmit behaviors through processes of social or cultural learning.
Culture is increasingly seen as a process, involving the social transmittance of behavior among p ...
, in which it was reported that one monkey acquired various skills such as washing
sweet potato
The sweet potato or sweetpotato (''Ipomoea batatas'') is a dicotyledonous plant in the morning glory family, Convolvulaceae. Its sizeable, starchy, sweet-tasting tuberous roots are used as a root vegetable, which is a staple food in parts of ...
es in water,
[Kawamura, S. (1959). The process of sub-culture propagation among Japanese macaques. ''Primates, 2''(1), 43-60] and that these skills then spread through the monkey troops by
imitation
Imitation (from Latin ''imitatio'', "a copying, imitation") is a behavior whereby an individual observes and replicates another's behavior. Imitation is also a form of learning that leads to the "development of traditions, and ultimately our cu ...
.
See also
*
Satsue Mito
*
Hundredth monkey effect
The hundredth monkey effect is an esoteric idea claiming that a new behavior or idea is spread rapidly by unexplained means from one group to all related groups once a critical number of members of one group exhibit the new behavior or acknowledge ...
References
External links
Pictures of Kōjima
Islands of Miyazaki Prefecture
{{Miyazaki-geo-stub