Aromorphosis - is adaptive changes of living organisms that occur in the course of evolution, have a common meaning and aimed at increasing the level of the organization, which increases vitality.
total value aromorphoses
aromorphoses The appearance is crucial in the struggle for existence.Living organisms in which such changes occur, are becoming more attuned to environmental conditions and can master the new environment.Aromorphosis is any example of evolutionary change, which leads to the appearance of new, progressive groups of organisms.
aromorphoses formation is a lengthy process and is associated with genetic variation.In addition, the value of new properties in the appearance of living beings have a natural selection when more adapted organisms survive.They have more physiological capabilities to fight for its existence and provide the children with a greater number of useful properties that are passed to the next generation.
can say that is an important morphophysiological aromorphosis process.It leads to more complex organisms that are less dependent on environmental conditions.
Aromorphoses plants
Progressive changes typical for plants.They relate not only to improve the morphological features, so often instead of "aromorphosis" used the word "arogenez", which means "origin".
appearance of different types of algae associated with different combinations of morphological properties and the ability to photosynthesize, but the real tissue they do not have, so they are considered primary aquatic organisms (evolutionary changes in their structure are not available).
If aromorphosis examples indicate, the most important may be called differentiation of tissues, which led to the emergence of terrestrial higher plants.The most primitive of them - it mosses, because these plants went poorly differentiated cells, not the root, but the shoots are characterized by a primitive structure.
next important aromorphosis was the division of the body to escape, and the plant roots.In the future, any spore plants, which include ferns, horsetails and club mosses, but they still lack seeds, and sporophyte develops from an embryo that is a little differentiated.Since water is needed for fertilization, it is to some extent limits the widespread spore plants.
Examples aromorphosis plants
If we talk about radical changes in the structure and composition of the plant, you should remember Gymnosperms department, whose representatives have a number aromorphoses:
- they have an ovule, which is developing endosperm (female gametophyte);
- are pollen grains that grow in the pollen tube;male gametophyte is formed;fertilization does not need water;
- in these plants have seeds that are composed of well-differentiated embryo and endosperm, which is the source of nutrients for embryo development.
to the seed plants still belong to angiosperms.They emerged in the Jurassic period.Examples aromorphosis this department the following plants:
- they always have a closed carpel ovules (the pistil);
- there are special "bait" - the nectar and perianth, which provide entomophily - pollination via insects, which is characterized by the accuracy of the process within a specific type and allows there different plants;
- for angiosperm embryo sac is typical with such a structure, which allows the passage of double fertilization.
It should be noted that this group of plants includes about 250 species and is on the way biological progress.So, angiosperms are represented by different life forms (which trees, shrubs, vines, grasses, water representatives) who are constantly being improved with respect to the structure and functions of the individual parts.
Evolutionary changes in the structure of animal
eukaryotic organisms, which were characterized by heterotrophic type of feeding, gave rise to mushrooms and animals.The first of these are single-celled organisms that had tissues.In the Proterozoic era appear multicellular invertebrate creatures.The most primitive animals were double-layer, for example Coelenterates.Examples aromorphosis the animals of this group - two-layer body and the germ, which consists of two sheets - the ectoderm and endoderm.
Another important improvement of the structure of the emergence of the middle germ layer - mesoderm, which triggered the differentiation of tissue and the appearance of organ systems (flat and round worms).Next aromorphosis the emergence of a whole - the secondary cavity, through which the body of the animals began to separate into sections.
emerged primitive protostomes (for example, Annelida), who already had parapodia (primitive limbs) and homonomous segmented body.Examples aromorphosis that occurred in the future - the emergence of heteronomous segmentation of the body and jointed limbs (any Arthropods).At the beginning of the Devonian occurred landfall arachnids and insects, who observed serious aromorphosis - the emergence of embryonic membranes.
Evolution deuterostome
The appearance of these organisms chord, the neural tube, the abdominal aorta, the heart and then led to the formation of a new type - chordates.In the future, the fish develops visceral and axial skeleton.So, they have observed the presence of the cranium and the jaw of the skull.
bony fishes have also passed a number of important aromorphoses (pulmonary respiration appeared and these of course) that gave rise to amphibians.
further develop amniotes, who had three embryonic membranes.The first reptiles began their representatives.They were independent of the water, but because of the lack of a closed circulation could not control a constant body temperature, which led to their mass extinction at the end of the Mesozoic.
Further examples aromorphosis - the appearance of a complete septum between the ventricles in the heart.It is possible to separate the circulation, leading to the appearance of warm-blooded animals, which later acquired the ability to fly.Thus arose the class of birds.
Aromorphoses that led to the emergence of mammals
mammal-like reptiles have increased over time hemispheres of the forebrain, the cortex has evolved, there was a four-chambered heart, took the reduction of the aortic arch.In addition, mammals arose due to the appearance of the auditory ossicles, the coat and mammary differentiation of teeth in the alveoli.The following example aromorphosis mammals - the appearance of the placenta and live birth.
For feeding calves milk, the progressive development of the lungs, brain, circulatory system, as well as a number of other aromorphoses - causes a sharp increase in the general level of the organization of animals and the emergence of higher organisms.
last significant aromorphosis can be called the increase of the brain in human ancestors (epimorphosis).Today, Homo sapiens learned adaptive area of land that has provoked the emergence of the noosphere.At the same time the organic world has entered a new era - psihozoynuyu.
To sum up, it should be said that large aromorphoses lead to the seizure of new habitats and the emergence of new organisms with specialized features that play a leading role in the evolutionary process.
