What is rudiment? It is part of a plant or animal organism that no longer fulfills its function for which it is intended. Living organisms abound in rudimentary structures, and their study provides additional opportunities for proving evolution.
Examples of rudiments in the animal kingdom
What are rudiments? Examples can be found everywhere. For example, dandelions, although they breed without fertilization, they still have flowers and form pollen. Among insects, you can find flightless beetles that have fully formed wings, hidden under the solid fused elytra.
Reptiles like pythons still have a rudimentary pelvis that is not attached to the vertebrae (like most vertebrates) - it simply swims in the abdominal cavity. This is evidence that the snakes came from four-legged reptiles. Some lizards carry rudimentary, rudimentary legs under their skin that are invisible from the outside.
Many animals have vestigial eyes. For example, underwater cave dwellers such as fish (Mexican tetra and salamander species Typhlotriton spelaeus and Proteus anguinus) are blind, but have rudimentary rudimentary eyes. The eyes of the Mexican tetra have a lens, a degenerative retina, and an optic nerve. Blind salamanders have eyes with pupils that cover their eyelids from external light.
Whales have a rudimentary pelvis and hind legs. The leg bones are present in the body of the whale, but are not attached to the rest of the skeleton. Instead, they are simply embedded in animal tissue. This is evidence of the evolution of whales from land ancestors, followed by loss of the hind limbs and pelvis. All that remains rudimentary in modern whales is the remains of these structures.
Human rudiments
What is rudiment? This is a part of the body that lost its direct destiny in the process of evolution, for example, the human appendix, which once performed an important function, but now does more harm than good. The tailbone is the remnant of the tail bones of the distant ancestors of primates - this is the residual part of the embryonic tail, which is formed in the human body, and then decomposes and is "eaten" by the immune system. And some people are still, although extremely rare, born with tails (atavisms).
Some people can move their ears, although this property is inherent in cats and other animals and is necessary for the localization of sounds during hunting. The ancestors of humans were known to be herbivores, and teeth were necessary for chewing and grinding plant foods. More than 90% of all adults have so-called wisdom teeth. These useless teeth sometimes grow abnormally and can cause severe pain. Often people just get rid of them.
The appearance of "goose bumps" in humans is also a vestigial sign. This reaction usually occurs when it is cold or scary. The muscles at the base of each hair act to lift the hair up. In animals, this function is associated with heat retention. The same thing can happen if the animal is at risk. This time, “standing fur” makes it possible for the beast to look more menacing and menacing.
Irrefutable Evidence
To study the standard phylogenetic tree, it can be noted that each species has a unique pedigree. Each organism has its own unique cycle of common ancestors, connecting it with them. Organisms are expected to bear evidence of this family history. What is rudiment? In biology, these are anatomical and molecular features that are non-functional.
What is rudiment? For example, the wings of birds are very complex from an anatomical point of view, structures specially adapted for controlled flight, but there are birds that are not allowed to fly. A striking example of this is ostriches, whose wings can be confidently called rudimentary organs, since they are not needed for flight, but rather for balancing while running and mating dances.
The bewilderment of scientists
Rudimentary structures perplex naturalists throughout history. This question was of interest to scientists long before Darwin first proposed his universal theory of the origin of species. Many scholars of the eighteenth and nineteenth centuries, such as Johann Wolfgang von Goethe (1749-1832), Georges-Louis Leclerc, Comte de Buffon (1707-1788), and Georges Cuvier (1769-1832), studied this problem.
Sixty years before Darwin’s Origin of Species publication, the outstanding French anatomy specialist Geoffrey Saint-Hilaire (1772–1844) dealt with the issue of vestigial wings in cassowary and ostrich. He was at a loss as to why nature always leaves “traces of an organ” that is no longer needed. Ten years later, Jean-Baptiste Lamarck (1744-1829) defined some rudimentary structures in his Zoological Philosophy.
Atavisms
Atavisms are certain characteristics inherent in only a small group of organisms. Examples are human tails (coccygeal projection), extra or webbed fingers, abnormal hairiness, hyoid muscle in dogs, and so on. Some genes, such as the fluff in an infant, simply deactivate after childbirth. What are rudiments and atavisms? This is just the tip of the iceberg of evidence for evolution.
The characteristics of atavisms are:
1) presence in the adult stage of life;
2) the absence of signs in parents or recent ancestors;
3) extreme rarity in the population.
One of the most dramatic atavisms is human tails. Some of them are soft, containing only muscles, blood vessels and nerves. Cartilage may sometimes be present. These tails can be removed surgically. Atavism includes the presence of a large number of nipples (more than 2).
The mysteries of evolution
What are rudiments in biology? These are bodies that have lost their immediate purpose and no longer fulfill their direct functions. If all living organisms descended from a common ancestor, then the loss or acquisition of various functions and structures is determined by historical macroevolution.