Examples of aromorphosis in plants and animals

Aromorphosis is an adaptive change in living organisms that arise during evolution, have a common meaning and are aimed at raising the level of organization, which increases vitality.

The general meaning of aromorphoses

The appearance of aromorphoses is of decisive importance in the struggle for existence. Living organisms, in which such changes occur, become more adapted to the conditions of the external environment and can develop a new habitat. An example of aromorphosis is any evolutionary change that leads to the appearance of new, progressive groups of organisms.

The formation of aromorphoses is a fairly long process and is associated with hereditary variability. In addition, the importance of the appearance of new properties of living beings has a natural selection, when more adapted organisms survive. They have more physiological capabilities to fight for their existence and give more descendants with useful properties that are passed on to the next generations.

It can be said that aromorphosis is an important morphophysiological process. It leads to the emergence of more complex organisms, which are less dependent on environmental conditions.

Aromorphoses in plants

Progressive changes are also characteristic of plants. They concern not only the perfection of morphological features, so often instead of the term "aromorphosis" the word "arogenesis" is used, which in translation means "origin".

The appearance of various species of algae is associated with a different combination of morphological properties and the ability for photosynthesis, but they lack real tissues, and therefore they are considered primary aquatic organisms (there are no evolutionary changes in their structure).

If you specify examples of aromorphosis, the most important is the differentiation of tissues, which led to the emergence of terrestrial higher plants. The most primitive of these are mosses, since in these plants the differentiation of cells has been weak, the root is absent, and shoots are characterized by a primitive structure.

The next important aromorphosis was the division of the body of the plant into shoot and root. Later, sporogenous plants appeared, to which include ferns, horsetails and mussels, but they still do not have seeds, and the sporophyte develops from the embryo, which is little differentiated. Since water is needed for fertilization, this to a certain extent limits the wide spread of spore plants.

Examples of aromorphosis in plants

If we talk about radical changes in the structure and structure of plants, we should remember the Department of Gymnosperms, whose representatives have a number of aromorphoses:

• They have ovules, in which endosperm develops (female gametophyte);
• There are pollen grains that germinate in the pollen tube; A male gametophyte is formed; Fertility does not require water;
• These plants have seeds that consist of a well-differentiated embryo, as well as endosperm, which is a source of nutrients for the development of the embryo.

Seed plants also belong to the Angiosperms. They arose in the Jurassic period. Examples of aromorphosis of this plant department are as follows:

• They always have a closed carpel with a seed (pestle);
• There are special "baits" - nectar and perianth, which provide entomophily - pollination with the help of insects, which is characterized by the accuracy of the process within a particular species and allows to exist to different plants;
• For angiosperms is characterized by a germinal sac with a structure that allows for double fertilization.

It should be noted that this group of plants has about 250 species and is on the path of biological progress. Thus, angiosperms are represented by various life forms (these are trees, bushes, lianas, grasses, water representatives), which are constantly being improved with respect to the structure and functions of individual parts.

Evolutionary changes in the structure of animals

Eukaryotic organisms, which were characterized by a heterotrophic type of feeding, gave rise to fungi and animals. The first of these are unicellular organisms that did not have tissues. In the Proterozoic era , multicellular invertebrate beings appear. The most primitive were two-layered animals, for example, the Intestinal. Examples of aromorphosis in animals of this group are a two-layered embryo and a body that consists of two sheets of ectoderm and endoderm.

The next important improvement in the structure was the appearance of the middle germinal leaf - the mesoderm, which provoked the differentiation of tissues and the appearance of organ systems (Flat and Roundworms). The next aromorphosis was the appearance of a coelom - a secondary cavity, thanks to which the animal body began to divide into divisions.

Primitive Primitives (for example, Ringworms), which already had parapodia (primitive limbs) and a homogeneous segmented body, appeared. Examples of aromorphosis, which occurred later, are the appearance of heteronomic segmentation of the body and segmented limbs (arthropods have arisen). At the beginning of the Devonian, there arose a land of arachnids and insects on land, in which a serious aromorphosis was observed-the emergence of embryonic membranes.

Evolution of the recycled

The appearance of the chord, the neural tube, the abdominal aorta, and then the heart resulted in the formation of a new type - chordates. Subsequently, the visceral and axial skeleton develops in fish. So, they already have a brain box and jaw section of the skull.

Bone fish also underwent a number of important aromorphoses (pulmonary respiration and real limbs appeared), which gave rise to amphibians.

Further develops amniotes, which had three embryonic membranes. The first of their representatives were reptiles. They were independent of water, but because of the lack of a closed circle of blood circulation, they could not control the constant temperature of the body, which led to their mass extinction at the end of the Mesozoic.

Further examples of aromorphosis are the appearance of a full septum in the heart between the ventricles. This allowed us to divide the circles of blood circulation, which led to the appearance of warm-blooded animals, which later acquired the ability to fly. So the class of the Bird appeared.

Aromorphosis, which led to the appearance of mammals

In the hunter-toothed reptiles, the hemispheres of the forebrain increased over time, the cortex developed, a four-chambered heart appeared, and the aortic arch was reduced. In addition, mammals arose due to the appearance of auditory ossicles, wool cover and mammary glands, differentiation of teeth in the alveoli. The following example of aromorphosis in mammals is the appearance of the placenta and live birth.

Thus, the feeding of cubs with milk, the progressive development of the lungs, brain, circulatory system, as well as a number of other aromorphoses - causes a sharp increase in the overall level of animal organization and the emergence of higher organisms.

The last significant aromorphosis can be called an increase in the brain in human ancestors (epimorphosis). To date, the Intelligent Man has mastered the adaptive zones of the earth, which provoked the appearance of the noosphere. At the same time, the organic world entered a new era - a psychosis.

Summing up, it should be said that large aromorphoses lead to the seizure of new habitats and the emergence of new organisms with specialized characteristics that play a leading role in the evolutionary process.