Strictly speaking, metamorphosis is any transformation, transformation that takes place in the Universe. This term is quite general and is used in various fields of scientific knowledge. In this article we will consider the concept from the point of view of biology. Within the framework of the science of life, it is more correct to call the phenomenon "metamorphosis", in the masculine gender, further both possible options will be used.
So, in biology, metamorphosis is a pronounced morphological change in a living organism, which necessarily occurs during its ontogenesis. The phenomenon is observed in both plants and animals. In the latter, metamorphosis occurs in the life cycle of most invertebrates and some vertebrates: cyclostomes, fish, and amphibians. The essence of the process lies in the transformation of the larval organism (in animals) or some organs (in plants) in such a way that the formed adult organism as a result radically differs from the newborn in structure, physiology and vital activity.
For animals, metamorphosis is not only a sharp change in the structure of the body. The phenomenon is accompanied by a change in habitat and conditionsexistence. The vital activity of an adult organism is completely different from that of the larval stages, the difference lies in the habitat, food consumed, and many other details. Thus, we discover the essential importance of metamorphosis in nature, it ensures the reduction of biological competition for food, habitat and other factors between organisms of different generations of the same species.
Let's take a closer look at metamorphosis in animals. Perhaps the most striking example would be the class of insects. Metamorphosis is characteristic of all representatives of this group. The process is either complete transformation or incomplete. Complete metamorphosis involves three stages of development of the organism: worm-like larva, pupa (the immobile stage, during which the body of the larva is completely destroyed and a new body of an adult is formed) and an adult insect. This type of phenomenon is typical for Diptera (flies, mosquitoes), Hymenoptera (bees, bumblebees, wasps), Lepidoptera (butterflies), Coleoptera (ladybugs). With incomplete metamorphosis, only two stages of development are observed: a larva, morphologically similar to an adult, and, in fact, an adult insect. Incomplete transformation is characteristic of orthoptera (locusts, grasshoppers, bears), homoptera (aphids) and hemipterans (bugs).
For higher plants, metamorphosis is a modification of individual organs in connection with their functions, and not a transformation of the whole organism. As a rule, rudimentary rather than fully formed organs enter the process. Plant metamorphoses alsoare called modifications. These are, for example, bulbs (for onions), thorns (for cactus), antennae (for grapes), rhizome (for ginger), tubers (for potatoes) and much more. The significance of metamorphosis for plants lies in their adaptation to environmental conditions. So, for example, thorns (modified leaves), found in plants living in hot climates, by their shape help to reduce evaporation from the leaf surface.
