偶蹄目（Artiodactyla）源于希腊文ἄρτιος（ártios,"偶数"）和希腊文δάκτυλος（dáktulos,"手指、脚趾"）,意为 "偶蹄",指的是这些动物的五个脚趾中,有两个（偶数）平均承受重量：第三和第四个,通常呈蹄状.其他三个趾要么存在,要么不存在,要么是残余的,要么指向后方.

Artiodactyla, from Greek ἄρτιος (ártios, “even”) and Greek δάκτυλος (dáktulos, “finger, toe”), means “even-toed”, in reference to the fact that these animals bear weight equally on two (an even number) of their five toes: the third and fourth, often in the form of a hoof. The other three toes are either present, absent, vestigial, or pointing posteriorly.

種的俗名 Common names of members

豬,西貒科,河馬,羚羊,鹿,長頸鹿,駱駝,大羊駝,羊駝,綿羊,山羊,家牛,鯨魚,海豚,鼠海豚.

Pigs, peccaries, hippopotamuses, antelopes, deer, giraffes, camels, llamas, alpacas, sheeps, goats, cattle, whales, dolphins, and porpoises.

分佈 Distribution 

所有大洋和大陆（澳大利亚和一些大洋岛屿除外）.

All oceans and continents (except Australia and some oceanic islands).

體型 Size

体型差异很大：最小的成员通常只有 45 公分长,1.5 公斤重.最大的体长可达 26 米,重达 130 公吨.

Size varies considerably: the smallest members often reach a body length of only 45 centimeters and a weight of 1.5 kilograms. The largest can grow up to 26 m in length and weigh 130 metric tons.

形態描述 Morphology 牠们一般是四足动物.目前已知的主要有两种体型：麂类和河马的特点是身体粗壮、腿短、头大（鲸鱼和海豚也是如此,但牠们的体型呈流线型,前肢是鳍状肢）；骆驼和反刍动物的体型则更为纤细,腿也比较长.牠们的指头都很短小.牠们都只剩下第 3 和第 4 个指头.有些还退化了第 2 和第 5 指.牠们的脚趾横向对称.

They are generally quadrupeds. Two major body types are known: Suinids and hippopotamuses are characterized by a stocky body, short legs, and a large head (as well as whales and dolphins, but these play a streamlined shape, and their forelimbs are flippers); camels and ruminants, though, have a more slender build and lanky legs. Their digits are reduced. All of them have 3rd and 4th digits remaining. Some also have reduced 2nd and 5th digits. Their toes are laterally symmetrical.

生態與棲息地 Ecology & Habitat

所有陆地（草原、森林、山地、沙漠等）和海洋环境.

All terrestrial (grassland, forest, mountain, desert, etc.) and oceanic environments.

食性 Diet 陆生动物以草食为生（草、根、果实、树叶等）,但水生动物通常只以肉食为生（鱼、磷虾、浮游生物、软体动物、海豹等）.

The terrestrial ones play herbivorous diets  (grasses, roots, fruits, leaves, etc), but the aquatic ones often play exclusively carnivorous diets (fish, krill, plankton, mollusks, seals, etc).

繁殖 Reproduction 

牠们中的许多都生活在社会群体中.幼崽与母亲生活在一起,雄性可能会陪伴幼崽,这取决于种类.在某些物种中,社会群体甚至包括前一年的幼崽.大多数雄性都会在交配期间捍卫自己的领地.雄性还会品尝雌性的尿液,以便锁定准备交配的个体.牠们中的大多数一年只會生一只幼崽. 

Many of them live in social groups. The young live with their mother and the male may accompany them depending on species. In some species, the social group even includes the young of the previous year. Most of the males will defend their territories during the mating period. Males will also taste the urine of females to target the individuals which are ready for mating. Most of them only give birth to one young in a year. 

已知的物種

Total species known

551

博物館收藏的物種

Species in the collection

14

在香港已知的物種

Species in Hong Kong

3

References

- Spaulding, M., O'Leary, M. A., Gatesy, J. (2009). Relationships of Cetacea (Artiodactyla) Among Mammals: Increased Taxon Sampling Alters Interpretations of Key Fossils and Character Evolution. PLOS ONE. https://doi.org/10.1371/journal.pone.0007062. 

Macdonald, D. W. (2006). The Encyclopedia of mammals. Oxford University Press. https://doi.org/10.1093/acref/9780199206087.001.0001.