2. Zi [Hu and r]? ~ Zi [Hu and R]?
Onomatopoeic words, describing the sound of horses barking.
Extended data
Horses and horses are divided into vertebrates, mammals, Chiroptera, Equidae, Equus, Equus (Equus? It is a herbivore. There are two subspecies of domestic horse and Platts wild horse.
Since the horse was domesticated by human beings, in the long development process, due to the influence of natural environment in various regions and the needs of social and economic development in different periods, the use of horses has experienced the process of alternation or mutual integration of meat, milk, agricultural production, transportation, military and sports entertainment.
According to fossil research, Shi Xinma, the ancestor of Equus, appeared 55 million years ago.
In former North America, its body was as big as a fox, feeding on juicy tender leaves, with four fingers on its front foot and three toes on its back foot.
Subsequently, the topography, climate and ecology of nature changed, and an open inland plain appeared, and the evolution of horses gradually adapted to these changes. The evolution of horses has gone through the main stages of development, such as the first horse, the middle horse, the original horse, the new horse and the real horse. Its main evolutionary characteristics are: the body becomes bigger; The height increased from 40cm to more than 120cm; Toe evolved from three toes or four toes to one toe (single hoof) to facilitate running; The teeth change from low crown structure to high crown structure, and the teeth are hard and wide and wrinkled, which is beneficial to eating hay; Brain volume increases.
The first horse: short head and neck, bent back, about 40cm in height, four toes on the front foot and only three toes on the back foot. The ulna of the forelimb and the fibula of the hind limb are slender, but they are still separated. The molars are short, the crowns are low, and the protrusions are mound-shaped. Living in bushes, eating fresh and juicy leaves and soft grass.
Ma Zhong: It's a little bigger, about 50 centimeters high. There are only three toes in the front and rear limbs, and the middle toe is particularly developed and can support most of the weight. Still living in the forest, you can run very fast on hard ground.
Yuanma: It is an important intermediate transitional form, and its living environment is transferred to grassland, feeding on coarse grass. Body size increases, teeth are harder, skull volume increases, and face becomes longer. There are three toes on each foot, and only the middle toe touches the ground when walking.
Shangxinma: It is about12 million years ago and its height is about 100cm. There are still only three toes in each limb, only the middle toe is exposed, and the second and fourth toes on both sides are twiglike residues.
Real horse: It first appeared about 6.5438+0 million years ago. The limbs have completely become single hoof, but there are still significant differences compared with modern domestic horses, such as large and long skull, small and wrinkled tooth surface, slender limbs, developed middle toe of each foot, and degenerated phalanges on both sides. The four ancestors of domestic horses evolved from real horses: Platts Wild Horse, Forest Horse, Frozen Primitive Horse and Tatar Horse.
Compared with the ancient DNA sequencing data, it is found that Platts is not the ancestor of domestic horses, and its differentiation time is between 38,000 and 72,000 years, much earlier than the domestication time of domestic horses. The ancestral differentiation time of Equus is about 4-4.5 million years. In the past 2 million years, the number of horses has fluctuated greatly; It is also found that in the evolution of horses, great choices have taken place in the pathways related to immunity and smell. ?
According to a great deal of evidence about Tiber culture in northern Kazakhstan published in Science magazine in recent years, horses were domesticated in the Eurasian steppe at least 5,000 years ago in the Bronze Age. There may be three purposes for the earliest domestication of horses: one is to keep the surplus hunting horses as food sources, the other is to serve and shoot horses, and the third is to sacrifice or watch.
Reference source: Baidu Encyclopedia-Horse