Treeshrew - Tsupai (English spelling)

A general term for animals belonging to the family Tupaiidae in the order Tree Shrews. Also known as the wood mouse or squirrel-like mouse. The members of this family Tupaiidae are divided into two subfamily Tupaiinae and Ptilocercinae. The former is diurnal or crepuscular, and includes four genera: Tupaia , Anathana , Urogale , and Dendrogale , while the latter is nocturnal, and includes only one genus, Ptilocercus . They are small animals that look like mice or squirrels, and were once considered insectivorous, but in the 20th century they were classified as primates. However, since the late 1960s, attempts have been made to reexamine the tree shrew's phylogenetic position, and as a result, there has been a growing trend to return them to the insectivorous order. Since then, they have been treated as an independent order. In any case, it is important to note that tree shrews show intermediate characteristics between insectivores and primates.

They live from India to southern China and Southeast Asia, and the distribution of the family covers the range from 28 degrees north to 9 degrees south, and 72 degrees to 127 degrees east. They have a long, protruding muzzle and all four fingers have claws. Size varies by species, but they weigh 50-250 grams, have a head and body length of 10-24 centimeters, and a tail of roughly the same length, measuring 11-22 centimeters, and most species are bushy. Their fur is gray or brown, and some can be dark or reddish, with black spots or light stripes. The dentition is

They have 38 teeth. The molars in the upper jaw are insectivorous. On the other hand, other characteristics such as the bones around the eye sockets, the first digit of the forelimb being separated from the other digits, the olfactory organs showing a tendency to degenerate, and well-developed vision are primate-like. They are omnivorous, semi-terrestrial and semi-arboreal, and move swiftly, eating fruits, insects, small reptiles, etc. The social structure of many species is unknown, but like the common tree shrew, each individual has an area of ​​activity that is antagonistic between the same sex and overlapping between the opposite sex, and it is assumed that they basically have a solitary, pair-type (or harem-type) breeding system. The gestation period is 41 to 50 days, and they give birth to 1 to 3 babies per litter, usually 2.

[Shigeo Uehara]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

哺乳(ほにゅう)綱ツパイ目ツパイ科に属する動物の総称。別名キネズミまたはリスモドキ。この科Tupaiidaeの仲間は、ツパイ亜科Tupaiinaeとハネオツパイ亜科Ptilocercinaeに二分される。前者は昼行性か薄明薄暮性で、ツパイ属Tupaia、マドラスツパイ属Anathana、フィリピンツパイ属Urogale、ピグミーツパイ属Dendrogaleの4属を含み、後者はハネオツパイ属Ptilocercus1属のみで夜行性である。外見はネズミやリスに似た小動物で、古くは食虫目とみなされ、20世紀に入り霊長目に分類されるようになったが、1960年代後半以降、ツパイの系統上の位置の再検討が試みられた結果、食虫目に戻される傾向が強まった。その後、独立のツパイ目として扱われるようになった。いずれにしても、ツパイが食虫類と霊長類の中間的特徴を示していることは重要である。

　インドから中国南部、東南アジアにかけて生息し、科としての分布は北緯28度～南緯9度、東経72度～127度の範囲を覆う。鼻口部は長く突出し、四肢の指はすべて鉤(かぎ)づめをもつ。大きさは種ごとに異なるが、体重は50～250グラム、頭胴長10～24センチメートル、尾もほぼ同長で11～22センチメートルあり、多くの種ではふさふさしている。体毛は灰色ないし茶褐色で、暗色や赤みを帯びたり、黒い斑点(はんてん)や明るい縞(しま)模様をもつものもある。歯式は

で38本。上顎(じょうがく)大臼歯(だいきゅうし)の形態は食虫類的である。一方、眼窩(がんか)周囲の骨が発達し、前肢第1指が他の指から分離し、嗅覚(きゅうかく)器官が退化傾向をみせ、視覚がよく発達しているなどの特徴は霊長類的である。雑食性の半地上・半樹上生活者で敏捷(びんしょう)に動き、果実、昆虫、小形爬虫(はちゅう)類などを食べる。社会構造は不明の種が多いが、コモンツパイのように、同性間は対立的で、異性間では重複するような行動域を各個体がもち、単独行動・ペア型（ないしハレム型）繁殖システムが基本的と推定される。妊娠期間は41～50日で、1産1～3子、普通は2子を産む。

［上原重男］

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