Primitive mammals: animal insectivores

Animals insectivores have the main distinguishing feature from other mammals - this is an elongated head with an elongated muzzle, considerably protruding beyond the skull, in some cases similar to a trunk. These animals belong to the order of primitive mammals. They are different in appearance and way of life. But all the representatives are pretty lovely and funny insectivorous animals (the photo serves that proof). Their limbs are five-fingered and are provided with claws. The teeth of these animals are insectivorous, that is, they are adapted to gnaw at chitin. Fangs are necessarily present. The incisors are rather long, forming mites among themselves. The molars are covered with tubercles. Ears and eyes are of small size and do not throw oneself into the eyes. The brain in insectivorous animals is primitive (the large hemispheres do not have furrows) and does not cover the cerebellum. These creatures inhabit the entire globe, except Australia and much of South America. Species of insectivorous animals are divided into four families: tenreous, hedgehog, shrew, and jumper.

Fossil insectivores

Animals insectivores are one of the most ancient groups of higher animals. Archaeologists have found their remains in the Upper Cretaceous sediments of the Mesozoic era. It's about 135 million years ago. At that time there were quite a few insects on the Earth that were food for other animals, so many ancient mammals (judging by the structure of the jaw) used them in the diet. Many species of ancient animals were larger than modern insectivorous animals, examples of this - dienogalerix and lepticidium. Their well-preserved remains were found in Germany, in the Eocene sediments near Messel. In general, representatives of insectivorous animals always had small dimensions.

Lifestyle

Some species of insectivorous animals lead a different way of life: woody, subterranean or semi-aquatic. Most of the night activity. Individual species are awake practically around the clock. The basis of the diet is, of course, insects and small underground animals. But some insectivorous animals are predators. Individual representatives eat juicy sweet fruits, and in the period of lack of feed, their seeds can become their food. The stomach of these animals is simple. The cecum is absent in some species. All members of this squad are polygamous. In females, the uterus is bicorn. In males, the testicles are located in the groin or in the scrotum. Pregnancy in females runs from a decade to a year and a half. Within one year, there is usually only one litter, in which there may be up to 14 young. Full-aged insectivorous animals become in the period from 3 months to 2 years. The appearance of the animals is different, for example, hedgehogs have needles, the long-tailed shrew has a long tail flattened along its sides, and the moles have two shoveled front paws.

Insectivorous animals of Russia

In our country, insectivorous animals are represented by species: moles, muskrats, hedgehogs and shrews. The old hedgehogs and shrews were considered popular among the people, since they destroy exclusively harmful insects. Moles were considered half-useful beasts - they destroy various soil inhabitants, including the larvae of the May beetles, but also eat useful earthworms. Also, breaking through their endless underground passages, moles are harmed by forest, garden and garden plantings. But the fur of these animals is considered expensive furs, and they are the objects of hunting. Earlier in Russia, they hunted for suckers.

Biological and economic importance

Animals insectivores are links of various natural biocenoses. For example, loosening the soil, improving its quality, and regulate the number of insects in the litter of the forest. For man their existence is also important, as these animals eat and agricultural pests. Some species of insectivorous animals are objects of fur trade (muskrats, moles and others). But these animals can pose a serious danger to humans, since some of them are carriers of ticks, and with them of many dangerous diseases (leptospirosis, tick-borne encephalitis , etc.). Such rare species as spittle or muskrat are listed in the Red Book and are protected by the state.