袋鼠 Kangaroo

袋鼠是一類有袋類動物，屬於袋鼠科（Macropodidae），「袋鼠」一詞通常用來指袋鼠科中體型最大的幾個物種。

一般而言，大型袋鼠面對人類在澳洲的開發有較高的適應力；相較之下，他們的許多小型親戚則面臨了較大的生存威脅，數量也較少。

目前並沒有大規模的袋鼠養殖業，不過野生的袋鼠會被獵殺並製成食用肉品，而此種產業也具有爭議性^[2]。

據傳說，「Kangaroo」是袋鼠的英文名，源自於澳洲原住民 Guugu Yimidhirr :「gangurru」，意思是指「不知道」。而這一切其實只是一場誤會，約瑟夫·班克斯的第一次航海旅行時，他抵達努力河（即現時庫克鎮港口）岸邊。在靠岸修理船艦的七個禮拜其間，他意外地發現到一種古靈精怪的動物，便去詢問當地澳洲土著，但是由於語言不通，將「不知道」當做「袋鼠」的英文名稱，就一直使用到現在。^{[查证请求]}但事實上，經語言學家John B. Haviland 研究，當地稱呼袋鼠即為「ganguro」，其意義並非「不知道」^[3]。

袋鼠是澳洲的象徵物，出現在澳洲國徽中^[4]，以及一些澳洲貨幣圖案上^[5]。許多澳洲的組織團體，如澳洲航空^[6]，也將袋鼠作為其標誌。澳大利亚军队的车辆，舰船在海外执行任务时很多时候都会涂上袋鼠标志。

据袋鼠动物性特征：^[7]

动物学家考证，袋鼠是袋类动物的典型代表。袋类动物是发育不完全的动物，属早产胎儿，所以需要在育儿袋中发育。母袋鼠有四个乳头，两个高脂肪，两个低脂肪，母袋鼠一般每胎产3至4个仔，袋鼠出生后即要入袋，食用低脂肪乳水，这就决定了每胎袋鼠仔只能存活2个。袋鼠出生时非常小，大约只有1粒花生米那么大，成年袋鼠的身高有2.6米，体重可以达到50公斤。袋鼠用下肢跳动，奔跑速度非常快，时速可达50公里以上。袋鼠有一条“多功能”的尾巴，其作用非常大，在休息时它可以支撑于地，与双下肢共同起到平衡身体的作用，跑动中尾巴更是重要的平衡工具，另外袋鼠尾巴还是重要的进攻与防卫的武器。

The kangaroo /ˌkæŋɡəˈruː/ is a marsupial from the family Macropodidae (macropods, meaning "large foot"). In common use the term is used to describe the largestspecies from this family, especially those of the genus Macropus: the red kangaroo, antilopine kangaroo, eastern grey kangaroo and western grey kangaroo.^[1] Kangaroos are endemic to the Australia. The Australian government estimates that 34.3 million kangaroos lived in Australia in 2011, up from 25.1 million one year earlier.^[2]

As with the terms "wallaroo" and "wallaby", "kangaroo" refers to a polyphyletic grouping of species. All three refer to members of the same taxonomic family, Macropodidae, and are distinguished according to size. The largest species in the family are called "kangaroos" and the smallest are generally called "wallabies". The term "wallaroos", a portmanteau, refers to species of an intermediate size.^[3] There is also the tree-kangaroo, another genus of macropod, which inhabits the tropical rainforests of New Guinea, far northeastern Queensland and some of the islands in the region.

Kangaroos have large, powerful hind legs, large feet adapted for leaping, a long muscular tail for balance, and a small head. Like most marsupials, female kangaroos have a pouch called a marsupium in which joeys complete postnatal development.

The large kangaroos have adapted much better than the smaller macropods to land clearing for pastoral agriculture and habitat changes brought to the Australian landscape by humans. Many of the smaller species are rare and endangered, while kangaroos are relatively plentiful.

The kangaroo is an unofficial symbol of Australia and appears as an emblem on the Australian coat of arms^[4] and on some of its currency^[5] and is used by some of Australia's well known organisations, including Qantas^[6] and the Royal Australian Air Force.^[7] The kangaroo is important to both Australian culture and the national image, and consequently there are numerous popular culture references.

Wild kangaroos are shot for meat, leather hides, and to protect grazing land.^[8] Although controversial, harvesting kangaroo meat has some environmental advantages to limit over-grazing and the meat has perceived health benefits for human consumption compared with traditional meats due to the low level of fat on kangaroos.^[9]