"Natural Science 4" is an interactive encyclopedia that includes scientific information in the understanding of fourth grade students, wonderfully illustrated and animated.
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* Chapter 3 Lesson 19 *
* Adaptation of animals to the seasons *
The seasons influence the lives of animals. If in the warm season they are everywhere, in the cold they seem to disappear completely. Where are they, right? Well, animals adopt three different behaviors: hibernation, migration, or changing life forms. These behaviors allow the animals to withstand the cold and fight against food shortages during the winter.
In autumn, the bear prepares for hibernation. To make its den as comfortable as possible, it fills it with grass, leaves, ferns, mosses and lichens. However, unlike hedgehogs, which hibernate deeply, brown bears wake up easily. To survive the winter, the bear stocks up and eats large amounts of high-fat foods, as it loses about a third of its body weight during hibernation.
It is extraordinary how every year the birds gather in flocks and fly to warm countries. In our country there are 150 species of migratory birds or summer guests, among which the best known are the stork, the swallow, the wild ducks, the cuckoo, the nightingale and the pelican. One of the most amazing things about them is their ability to travel thousands of kilometers every year to spend the winter in warmer areas where they can find food.
To survive during the migration, the birds must be healthy, have a layer of fat and new feathers. The feathers destroyed on the journey to our country are exchanged for new ones in the summer. To reach their destination, migratory birds use the Earth's magnetic field thanks to a specialized receiver located just above the beak.
Many animals (mainly insects) change shape and are practically invisible in winter. At the end of summer, many insects die. However, they lay many eggs beforehand and bury them underground or in the hollow of a tree trunk. Most often these eggs withstand the cold due to a very solid membrane. In the spring, new insects in the form of larvae emerge from these eggs.
But animals adapt not only to the seasons, but also to light or darkness, depending on the abilities they have.
A nocturnal animal will have a more active life at night and a diurnal animal will be more active during the day. If it is safer or has an advantage to survive, then it will adopt the appropriate way of life.
Nature makes it so that the strongest and most adapted individuals survive, which is called natural selection. Some predators hunt their prey during the day or at night, choosing the option that brings them the most benefits. Nocturnal animals usually have sharper senses that allow them to better detect noises, movements, smells, and thus the presence of prey or predators around them. Their vision can be sharper, as in cats for example, and allows them to detect movement in the dark. Others have more efficient hearing, like owls or bats, and can thus detect the presence of prey just by the sound it makes.
Why do you think migratory birds return from warm countries?