Shrew - description, habitat, lifestyle

Many people know about miniature hummingbirds, which are small birds, but not everyone has heard about mammals the size of a pinky-sized mammal, and these also inhabit the planet. We are talking about shrews that belong to the order of insectivorous rodents and look like mice with an elongated muzzle, but first things first.

Basic information

The family of shrews is the most numerous of all that belong to mammals. This factor is caused by the special position of the shrews in particular and all similar vertebrates in general. After all, such small animals emerged in the evolutionary process in order to utilize various insects and other invertebrates, which in turn are engaged in ecosystems in the utilization of animal remains and other decaying organic matter.

Here we will make a small remark and remind readers of the unity of ecosystems,in which there are different varieties of living organisms and all perform some function, which can conditionally be reduced to the transfer of energy. Thus, plants draw on the energy of the sun and transform it, animals eat plants, and predators of other animals, and then they die and decompose. Then worms and insects come to the arena (there are other so-called ecosystem destroyers, for example, mushrooms), and then shrews appear, and other living organisms that eat the ecosystem destroyers. In general, there are a lot of worms and bugs in nature, and therefore this food supply allows for the development of their eaters, that is, insectivores, such as shrews.

There are about 700 species of shrews and they live all over the planet besides South America and Australia, but there are peculiar analogues of shrews - marsupials. They live mostly underground, but, despite their own name, they do not dig the earth. For the most part, they use the holes of moles and other animals, where they search for decaying remains, in other words, various corpses that they dispose of with the help of themselves.

Size may vary depending on the type, there are those that reach up to 10-12 centimeters, and there are representatives who weigh about one and a half grams. In this case, the smallest shrews eat every day in two or three more than their own weight. The rule also applies: the larger the shrew, the more plant food it eats, since, if the size of a species increases, its representatives cannot feed themselves only on organic remains that feed smaller animals.

Behavior features

These animals live in proud solitude, again because of the famine that does not allow them to create any interest groups or trade unions to search for corpses and other organic remains. When you always want to eat, you only think about it and no one intends to share their own food supply.Therefore, the shrew, as a rule, occupies a space of about 70 meters in the substrate of the earth and makes a daily detour to search for food. If an outsider (another shrew, a mouse, a lizard) turns out to be in a fight, which often ends in the death of one of the participants. Further, the one who defeated the opponent and uses this fodder base remains on the territory.

In addition, shrews are pretty tasty prey for larger animals. They are more easily harvested compared to mice and other rodents. Accordingly, the shrews themselves form part of the food base for the predators of their territory.

Much of the behavior depends on seasonality and, although small animals do not make their minks, in regions where there is winter, and the number of insects in the cold period is reduced, they can stock up provisions. In particular, mostly shrew shrews live on the territory of Russia. They stock up mostly coniferous nuts for the winter, which are supported by the lack of organic remains in the soil.

The most active in shrews is the autumn period, when you need to choose a plot for wintering.Survival depends on it and therefore in the fall shrews often quarrel with other animals and rodents and try to get a better home for themselves in order to spend a good winter.

Reproduction and development

In general, the existence of a shrew is quite fleeting, it lasts only a year. Sometimes representatives of this species can live for two years, but only under the most favorable circumstances and successful wintering. Approximately the life cycle is as follows:

1. Birth - in the summer-spring.
2. Summer expanse, food storage.
3. Autumn and the choice of housing for wintering, the effect of Danelia (about which we say below).
4. Spring jump in development, an increase of up to 50% of weight and puberty, which is combined with the subsequent reproduction.
5. Pregnancy is about three weeks and a three-week maturation of offspring.

Then the cycle repeats. If someone manages to spend the winter again, then they multiply the next year. This is not always the case.

If you look at the very style of reproduction and relationships, shrews are quite immoral (in human terms) creatures. As soon as the spring leap in development is completed, the males begin to look for a female and first mate with those who occupy the neighboring areas.As a rule, several males mate with one female, and in the litter there are children from each.

The males then continue to move on, that is, they leave their plots in search of a female, and she assigns this food base. There are about 6-8 pups in the litter, which the young mother tries to get rid of as soon as possible so as not to occupy her food base, but in practice, often the babies themselves chase their mother and occupy this territory. In general, as you can see, the housing problem spoils not only Muscovites, but also shrews.

During the summer season, female shrews can make about three broods. Especially if the female left (was kicked out) from her plot by her cubs, when she occupies a new plot, then there again she receives migrating males and the story repeats. And so up to 3-4 times per season. Such activity is caused by a short duration of existence.

Interesting facts about shrews

These animals are unique in many respects, and not to list all the features, but there is an opportunity to briefly tell you about some.

1. In fact, the shrew is a name peculiar to the purely Russian language and culture, in other countries these animals are called simpler, for example, they indicate a long nose or character. Thus, in English they are called the word “send,” which translates as obstinate and indicates the pugnacious character of the shrew.
2. A unique species of shrew lives in Africa, which has a shock-absorbing spine. However, the spine has the ability to depreciate in almost all vertebrates - you say. Quite right, but not to the same extent as the skeleton of a shrew absorbs, because if you step on this animal, its ribs simply shift, and nothing happens to the shrew itself.
3. Individuals have an incredibly active metabolism, and at the same time they eat incessantly (or are engaged in searching for food). This fact is caused by the need to maintain body temperature, because if large animals have thermal inertia (that is, if the body warms up, it cools down rather slowly), then such small ones as a shrew cannot use it, and they need to constantly receive energy, which is converted in bodily warmth.
4. Shrews have a species gradation at the choice of a diet. The smallest are predatory and hunt for bugs, the larger ones mostly go to earthworms. The largest use mainly vegetable diet.
5. Augustus Danelia discovered the effect, which was later named after him. This effect is to reduce the body of shrews before winter. In order not to look for more food, they simply make up less body and due to this they solve the problem with winter food decline. Surprisingly, these animals reduce the amount of water in the body through a series of biochemical reactions. Thanks to this even the size of the internal organs, the skull and the brain is reduced. By the way, this fact leads to some dulling of shrews, which can even lose some instinctive reactions. However, they needed brains in the summer during the search for food and mink, and in winter they only need to wait out the cold and live to spring breeding. Therefore, shrews know firsthand how sometimes it is good to be blunt.

In conclusion, the sad fact about shrews, which lies in their genetic predisposition to die a year after birth.In the second year of their existence, they do not have winter molting, which is so necessary for the cold weather and, in addition, for this year they almost completely erase teeth. Therefore, if shrews and avoid all predators and dangers, looking for the optimal food base, nature does not allow them to enjoy all this.

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