01529nas a2200193   4500008004100000245011500041210006900156260000900225300001400234490000800248520086200256653001301118653001001131653000901141653001101150100001501161700001801176856014101194       1993                        eng d00aElimination of external parasites (Lice) is the primary function of grooming in free-ranging Japanese macaques0 aElimination of external parasites Lice is the primary function o  c1993  a187 - 1930 v1013 aGrooming behavior was studied from September 1990 to May 1992 in the provisioned troop of free-ranging Japanese macaques (Macaca fuscata) at Jigokudani Monkey Park, Japan. By confiscating what macaques picked up during grooming, we found that macaques pick up lice (Pedicinus obtusus and Pedicinus eurygaster) and the eggs of lice and eat them. Slow motion video replays were used to discriminate the prey of grooming. Most (98.9%) of what Japanese macaques picked up and ate during grooming were the eggs of lice. Hence, allo-grooming has an altruistic function to eliminate the external parasites on others. In particular, grooming of infants by mothers appears to be important maternal care. On the other hand, in Japanese macaques, grooming is also insect-feeding behavior, and such selfish benefit may favor grooming under individual natural selection.10agrooming10aJapan10alice10aMacaca1 aTanaka, I.1 aTakefushi, H.  uhttps://phthiraptera.myspecies.info/content/elimination-external-parasites-lice-primary-function-grooming-free-ranging-japanese-macaques