Bats are the only mammals that can fly, the distribution on the earth is extremely wide, in addition to the north and south poles, almost all over the world, and the population is quite large, there are biologists think that the number of bats belonging to the order Pterodactyl or more than rodents, is the largest number of mammals, and bats have a special position in evolution, it has developed many very interesting biological phenomena, such as flight, echolocation, hibernation, etc., can be described as a fairly successful evolution of an animal, So how did bats evolve?
To explore the origin of bats, it is inseparable from archaeological biology, the oldest known bat fossils were excavated in the Green River Formation formation in Wyoming, USA, including the index finger bat and claw width, about 50 million years ago; later found that there are more complete bat fossils (ancient bats) in the bed of Lake Messer in Germany, which can also be traced back to the Eocene period, 47 million years ago.
But these early bat fossils are very similar to some of the existing suborder of small bats, and have an echolocation function, making it difficult to reproduce the earlier stages of their evolution; archaeologists have also found some 35 million years ago bat fossils, which are very similar to today's Chrysanthemum, in fact, from the fossil point of view alone, it is not possible to find out which animal the bat originated from.
However, biologists deduce that the ancestors of bats are likely to be related to the ancestors of primates, and the ancestors of the earliest primates are believed to be Purgatori monkeys, which can be traced back to more than 60 million years ago, and its size is not as large as today's mice, but it is not seen from this animal that there is any similarity with bats. There are also biologists who believe that rodents such as bats and mice have a common ancestor.
Purgatory Monkey
Bats belong to the order Pterodactyl, which contains two suborders, the suborder Of the Great Bat and the Suborder of The Small Bat, which biologists believe are likely to have evolved independently, but molecular biology has demonstrated a high degree of similarity between the two suborders, such as the fact that both contain higher levels of adenine and thymine base pairs. But some biologists believe that both types of bats consume a lot of energy in flight, and that evolutionary dynamics shaped them alone under similar conditions, not because they have a common ancestor.
Because flying requires more energy than other actions, bats are also considered to be mammals with the highest body temperature, with a body temperature of up to 40 ° C when flying, which also makes many viruses parasitic in bats, is a natural host of a variety of zoonotic viruses, the study found that bats can carry more than 800 kinds of viruses, the SARS virus in 2003 and the new, coronavirus that is currently raging around the world, are considered to be their early natural hosts are bats.
Although bats can carry a variety of zoonotic viruses, they are hardly infected themselves because of their unique immune mechanisms.
Resources:
Xiaoxiang Morning Post March 7 article "The Secret of Body Temperature: Why Is Human Immunity Inferior to Bats?" 》
"Hunan Hot News" July 27 article "Ancient Species - Bats"