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Cervidae belongs to the family Artiodactylidae. The common characteristics of Cervidae species are: the fur is gray, brown, reddish brown and yellow; Except reindeer with a black bare area on their nose; Most species have short tails, and elk has the longest tail. There are obvious black concave lacrimal fossa under the eyes; Each foot has four hooves, and the hooves are very small in shape.
Except for a few species, the canine teeth of most species degenerate or disappear; Except reindeer whose males have horns and whose females have no horns; Male antlers begin to shed at the end of the breeding season every year, and at the same time, they begin to grow new antlers. Entering the breeding period, the antlers are completely ossified.
According to the morphological characteristics of Cervidae, it can be divided into four subfamilies, among which the species of Cervinae are distributed in the American continent, while the species of Swertia, Cervinae and Muntjac are distributed in parts of Asia, Europe and Africa. Cervidae animals are distributed in all kinds of grasslands, forests, even deserts and tundra.
All deer feed on plants, and the larger species eat more kinds of plants. Leaves, stems, flowers and fruits of herbs, twigs, leaves and even branches and barks of woody plants are all on its "menu". The reproductive system is one male and many females. Species living in temperate and cold temperate zones have obvious breeding periods, while species distributed in tropical and subtropical zones can breed all year round.
Growth and reproduction
Horns are the second characteristic of stags (only reindeer Rangifer tarandus has horns for both sexes) and are also courtship weapons. Its growth and shedding are influenced by pituitary and testosterone. After the breeding season, the deer in the north shed their horns from Mao Kou below, and the next year they were born from Mao Kou above the 1 peduncle joint above the frontal bone. The newly grown horns are called velvet and cover the skin.
Hair, blood vessels, massive blood supply, branching; As the horn grows up, the blood supply gradually decreases and the skin dries out. When 1 ~ 2 years old, the initial angle is almost straight, and the bifurcation of the posterior angle increases year by year until adulthood. Female deer of horned species have no tusks if they have no horns.
Related report
On June 5438+065438+ 10, 2022, Canadian scientists discovered COVID-19 genetic material in nasal swab samples of three deer in southern Quebec, and isolated a live virus-COVID-19 new variant from two deer samples, which is the first evidence of the spread of COVID-19 deer.