The doctrine of evolution causes a lot of controversy. Some believe that God created the world. Others argue with them, saying that Darwin was right. They cite numerous paleontological evidence for evolution that most strongly support his theory.
The remains of animals and plants, as a rule, decompose, and then disappear without a trace. However, sometimes minerals replace biological tissues, resulting in the formation of fossils. Scientists usually find fossilized shells or bones, i.e. skeletons, the hard parts of organisms. Sometimes they find traces of the vital activity of animals or prints of their tracks. It is even rarer to find whole animals. They are found in permafrost ice, as well as in amber (the resin of ancient plants) or asph alt (natural resin).
Science paleontology
Paleontology is the science that studies fossils. Sedimentary rocks are usually deposited in layers, due to which the deep layers containinformation about the past of our planet (principle of superposition). Scientists are able to determine the relative age of certain fossils, that is, to understand which organisms lived on our planet earlier and which later. This allows you to draw conclusions about the directions of evolution.
Palaeontological record
If we look at the paleontological record, we will see that life on the planet has changed significantly, sometimes beyond recognition. The first protozoa (prokaryotes), which did not have a cell nucleus, arose on Earth about 3.5 billion years ago. About 1.75 billion years ago, single-celled eukaryotes appeared. A billion years later, about 635 million years ago, multicellular animals appeared, the first of which were sponges. After several tens of millions of years, the first mollusks and worms were discovered. 15 million years later, primitive vertebrates appeared, resembling modern lampreys. The jawed fish evolved about 410 million years ago, and the insects about 400 million years ago.
For the next 100 million years, mostly ferns covered the land, which was inhabited by amphibians and insects. From 230 to 65 million years ago, dinosaurs dominated our planet, and the most common plants at that time were cycads, as well as other groups of gymnosperms. The closer to our time, the more similarities are observed between the fossil fauna and flora with modern ones. This picture confirms evolutionary theory. She has no other scientific explanation.has.
There are various paleontological evidence for evolution. One of them is an increase in the duration of the existence of families and genera.
Increasing the duration of the existence of families and genera
According to available data, more than 99% of all species of living organisms that have ever lived on the planet are extinct species that have not survived to our time. Scientists have described about 250 thousand fossil species, each of which is found exclusively in one or more adjacent layers. Judging by the data obtained by paleontologists, each of them existed for about 2-3 million years, but some are much longer or much less.
The number of fossil genera described by scientists is about 60 thousand, and families - 7 thousand. Each family and each genus, in turn, has a strictly defined distribution. Scientists have found that genera live for tens of millions of years. As for families, the duration of their existence is estimated at tens or even hundreds of millions of years.
Analysis of paleontological data shows that in the last 550 million years, the duration of the existence of families and genera has steadily increased. This fact can perfectly explain the evolutionary doctrine: the most "hardy", stable groups of organisms gradually accumulate in the biosphere. They are less likely to die out as they are more tolerant of environmental changes.
There are other evidences of evolution (paleontological). By tracing the distribution of organisms, scientists have obtained very interesting data.
Distributionorganisms
The distribution of individual groups of living organisms, as well as all of them taken together, also confirms evolution. Only the teachings of Ch. Darwin can explain their settlement on the planet. For example, "evolutionary series" are found in almost every group of fossils. This is the name of the gradual changes observed in the structure of organisms, which gradually replace each other. These changes often look directional, in some cases more or less random fluctuations.
Presence of intermediate forms
Multiple paleontological evidence for evolution includes the existence of intermediate (transitional) forms of organisms. Such organisms combine the characteristics of different species or genera, families, etc. Speaking of transitional forms, as a rule, fossil species are meant. However, this does not mean that intermediate species must necessarily die out. The theory of evolution based on the construction of a phylogenetic tree predicts which of the transitional forms actually existed (and therefore can be found), and which ones did not.
Now many such predictions have come true. For example, knowing the structure of birds and reptiles, scientists can determine the features of an intermediate form between them. It is possible to discover the remains of animals that look like reptiles, but have wings; or similar to birds, but with long tails or teeth. At the same time, it can be predicted that transitional forms between mammals and birds will not be found. For example, there have never been mammals that had feathers; orbird-like organisms that have middle ear bones (typical of mammals).
Discovery of Archeopteryx
Palaeontological evidence for evolution includes many interesting finds. The first skeleton of a representative of the species Archeopteryx was discovered soon after the publication of Charles Darwin's work "The Origin of Species". This work contains theoretical evidence for the evolution of animals and plants. Archeopteryx is a form intermediate between reptiles and birds. Its plumage was developed, which is typical for birds. However, in terms of the structure of the skeleton, this animal practically did not differ from dinosaurs. Archeopteryx had a long bony tail, teeth, and claws on its forelimbs. As for the features of the skeleton characteristic of birds, he did not have many of them (fork, on the ribs - hook-shaped processes). Later, scientists found other forms intermediate between reptiles and birds.
Discovery of the first human skeleton
The discovery of the first human skeleton in 1856 also belongs to paleontological evidence of evolution. This event took place 3 years before the publication of On the Origin of Species. Scientists at the time of the book's publication did not know of other fossil species that could confirm that chimpanzees and humans descended from a common ancestor. Since then, paleontologists have discovered a large number of skeletons of organisms that are transitional forms between chimpanzees and humans. This is important paleontological evidence for evolution. Examplessome of them will be given below.
Transitional forms between chimpanzee and man
Charles Darwin (his portrait is presented above), unfortunately, did not learn about the many finds discovered after his death. He would probably be interested to know that this evidence for the evolution of the organic world supports his theory. According to her, as you know, we all descended from monkeys. Since the common ancestor of chimpanzees and humans moved on four limbs, and the size of its brain did not exceed the size of the brain of a chimpanzee, in the process of evolution, according to the theory, bipedalism should have developed over time. In addition, the volume of the brain should have increased. Thus, any of the three variants of the transitional form must necessarily exist:
- big brain, undeveloped upright posture;
- developed upright posture, chimpanzee brain size;
- developing upright posture, brain size is intermediate.
Remains of Australopithecus
In Africa in the 1920s the remains of an organism that was named Australopithecus were found. This name was given to him by Raymond Dart. This is another proof of evolution. Biology has accumulated information about many such findings. Later, scientists discovered other remains of such creatures, including the skull of AL 444-2 and the famous Lucy (pictured above).
Australopithecines lived in northern and eastern Africa from 4 to 2 million years ago. They had slightly larger brainsthan a chimpanzee. The structure of the bones of their pelvis was close to human. The skull in its structure is characteristic of upright animals. This can be determined by the opening in the occipital bone, which connects the cranial cavity with the spinal canal. Moreover, in the volcanic fossilized ash in Tanzania, "human" footprints were found that were left about 3.6 million years ago. Australopithecus is thus an intermediate form of the second of the above types. Their brain is about the same as that of a chimpanzee, they have a developed upright posture.
Ardipithecus remains
Later, scientists discovered new paleontological finds. One of them is the remains of an Ardipithecus that lived about 4.5 million years ago. After analyzing its skeleton, they found that the Ardipithecus moved on the ground on two hind limbs, and also climbed trees on all four. They had little upright posture compared to later hominid species (Australopithecines and humans). Ardipithecus could not travel long distances. They are a transitional form between the common ancestor of chimpanzees and humans and Australopithecus.
Much evidence of human evolution has been found. We have only talked about some of them. Based on the information received, scientists made an idea of how hominids changed over time.
Evolution of hominids
It should be noted that so far many are not convinced by the evidence for evolution. Origin Information Tableof a person, which is presented in every school textbook on biology, haunts people, causing numerous controversies. Can this information be included in the school curriculum? Should children study the evidence for evolution? The table, which is exploratory in nature, outrages those who believe that man was created by God. One way or another, we will present information about the evolution of hominids. And you decide how to treat her.
In the course of evolution, hominids first formed upright posture, and the volume of their brain was significantly increased much later. In Australopithecus, which lived 4-2 million years ago, it was about 400 cm³, almost like in chimpanzees. After them, our planet was inhabited by the species Handy Man. Its bones, whose age is estimated at 2 million years, have been found, and more ancient stone tools have been found. About 500-640 cm³ was the size of his brain. Further, in the course of evolution, a Working Man arose. His brain was even bigger. Its volume was 700-850 cm³. The next species, Homo erectus, was even more similar to modern man. The volume of his brain is estimated at 850-1100 cm³. Then came the sight of the Heidelberg Man. His brain size already reached 1100-1400 cm³. Next came the Neanderthals, who had a brain volume of 1200-1900 cm³. Homo sapiens arose 200 thousand years ago. It is characterized by a brain size of 1000-1850 cm³.
So, we have presented the main evidence of the evolution of the organic world. How you treat this information is up to you. The study of evolution continues to this day. Probably, new interesting finds will be discovered in the future. Indeed, at present, such a science as paleontology is actively developing. The evidence for evolution it provides is being actively discussed by scientists and non-scientists alike.
