The evolutionary process implies constant updates, the emergence of useful signs, their consolidation in the organisms of living beings. And these changes do not necessarily occur at the genetic level. Idiocaptations are very important - adaptations of animals, plants and microorganisms to specific living conditions, environmental factors and physical characteristics of the range.
The mechanism of the emergence of adaptations is a deep evolutionary process that forms the necessary traits over time, gradually. Fixing the necessary characteristics in the genome of living beings for manifestation in future generations.
Adaptations, or adaptations of organisms
Very often you can find an organism of plant or animal origin, which has some unusual feature in the structure, behavior or appearance. For example, stick sticks, which in appearance do not differ at all from a tree branch. Or a fly-bug, which has exactly the same color as a wasp. Among the plants, examples are thick-stalked fleshy cacti, stilted and airy roots, and props.
In any case, all this is adaptation to the environment, environmental conditions, or protecting oneself from other creatures. Such phenomena are very important because they are important stages of the evolutionary process. The mechanism of the emergence of adaptations always has in its basis precisely genetic samples and fixing of important and necessary genes encoding the manifestation of one or another trait. For example, the gene responsible for the color change of the chameleon was formed in the genome of these animals several thousand years ago and is still inherited by all future generations.
Plant Adaptation: General Description
Plant adaptations are an integral part of their life. All of them can be divided into several main groups.
- To environmental temperature conditions.
- Humidity.
- Pollination methods.
- To the consumption of food.
The mechanism of the emergence of devices meets all the same principles - evolutionary changes with fixing and inheritance of the necessary characteristics in specific conditions. Therefore, if any plant has adapted to the territory, environmental conditions, temperature, then it will definitely pass on all the features for a comfortable existence to all its future generations.
Dry plants
At a temperature regime in which too high values and constant sunny days prevail, plant adaptations have a pronounced character, aimed at reducing moisture evaporation. As well as maintaining body weight and nutrients along with bound water inside the stem.
To do this, leaf plates are reduced to a minimum, or completely mutated. The most typical example is desert plants - cacti. Severe conditions of existence under the scorching sultry sun forced these plants to transform leaves into prickly needles, and the stem into a thick fleshy trunk filled with parenchymal cells (main tissue) with a lot of bound and free water.
The mechanism for the emergence of cactus adaptations very clearly shows how skillful plants can be in their adaptations. Thanks to the thorns, the plant does not evaporate water from the surface of the leaves, which means it saves a large amount of it. In addition, in the stem, modified under a thick fleshy trunk, there is an accumulation of a number of substances that retain water. For example, accumulate:
- hydrophilic protein molecules;
- proline (water retention amino acid);
- monosaccharides and various organic acids.
Also, the mechanism of emergence of cactus devices includes the production of compounds of a hormonal nature that inhibit the action of growth hormones (gibberellins, auxins). This allows plants to quickly stop their growth under adverse conditions that last for a long time.
Adaptations to different types of pollination
Another striking example of adaptations in plants is their ability to adapt to pollinators. For example, wind-pollinated forms form seeds that are dry and light, which simply disperse even with gentle air movements.
If the plant is insect-pollinated, then it forms flowers of a certain structure and color:
- brightly colored;
- large or collected in large inflorescences;
- with a strong pleasant aroma.
The structure of the flower itself can also be adapted for a pollinator. There are plants pollinated by a strictly defined species of bird or insect.
Cross-pollinating or self-pollinating plants in the flower structure have long stamens and a deeply planted pestle so that the pollen falls on the stigma. Each of these adaptations plays an important role in reproduction and is also fixed hereditarily in the genome.
Excessive Humidity Conditions for Plants
In tropical and subtropical habitats, often the phenomenon of excessive air humidity. After all, it is known that in some places tropical rain can go more than a month. Of course, such an excess of water is very harmful to plants. Therefore, some species have formed certain adaptations that minimize this effect of nature. These are hydatodes - water estuaries that increase the amount of water secreted by the plant. She comes out whole drops. This phenomenon is called gutting.
Also adaptations to excess moisture in plants are large leaf plates with a huge number of stomata. Accordingly, transpiration is also enhanced.
The mechanism of occurrence of adaptations in animals
Representatives of the fauna are forced not only to adapt to environmental conditions, but also to protect themselves from the attack of stronger individuals, for whom they are food. This led to the formation of several types of adaptations in animals:
- a change in the shape of the body and limbs, coat (skin, feather);
- protective coloration;
- mimicry (imitation of more protected and dangerous animals);
- warning coloring;
- intimidating behavior.
A striking example of adaptations by changing the shape of the body, limbs and integuments are birds (feathers, keel, light skeleton, streamlined body shape). Also, aquatic mammals and fish that have tails and fins, a smooth surface, the absence of a powerful coat. But they have air bubbles, a sideline (in fish), membranes on their feet (waterfowl), flippers (marine mammals).
Protective color appears in many animals, both terrestrial and aquatic. For example, green grasshoppers hiding in the grass, sea needles hiding themselves in algae. Chameleons, moths (rod-shaped caterpillars), kalima (butterfly imitating leaf), partridge, white and gray coloring of hares and many other examples reflecting adaptations in animals.
Mimicry, that is, imitation in order to protect oneself from eating and attack, is characteristic, for example, of a fly-grouse (resembles a wasp), some species of snakes that replicate poisonous snakes, and so on.
The warning coloration of insects and animals is aimed at honest warning about the inedibility of the species, its toxicity. An example is poisonous snakes, wasps, bees, bumblebees, ladybugs and other representatives. These are very common adaptations in animals.
The intimidating behavior is hissing, growling, jumping to the side, releasing biological fluids (ink of octopuses and squids, skunks). This also includes the characteristics of some animals, which in the cold season form flocks to facilitate the procurement of food.
All of these devices are evolutionarily formed and genetically entrenched mechanism of education.
Adaptations of Polar Bears
The mechanism for the emergence of adaptations of the polar bear was formed in extremely cold habitats. All of his adaptations are aimed specifically at the preservation of heat and the extraction of food. These include:
- patronizing white color (disguise);
- a thick layer of subcutaneous fat, which plays a dual role: thermal insulation and weight gain during swimming and diving;
- Thick, dense and warm fur covering the entire surface of the body.
Thanks to its adaptations, the polar bear can not be afraid of even the most severe colds. And the white color allows him to sneak up on the source of food - seals.
Subsurface mammals
The most striking representative is, of course, the mole and all its relatives (zokors, mole rats and others). Therefore, on his example, consider adaptation. The mechanism of occurrence of mole adaptations is associated with an underground habitat devoid of some important abiotic factors: light, sufficient moisture, and heat. Therefore, the adaptations of this animal are as follows:
- powerful digging limbs;
- lack of vision;
- a thick subcutaneous layer of fat;
- smooth and hard coat of black color;
- streamlined body shape.
Adaptation of large desert animals
These primarily include camels, their various types. The mechanism for the occurrence of camel devices was formed under conditions of lack of moisture and high temperatures. Adaptations of the following nature:
- the presence of glands, eliminating excess salts in the body;
- reduced sweating;
- the ability to starve for a long time, losing a third of body weight;
- special features of digestion and metabolism;
- the presence of humps filled with fat storing bound water;
- fast saturation with water for replenishment of internal stocks.
All these adaptations make desert conditions for camels quite comfortable and acceptable for life.