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 provide numerous evidence of paleontological evolution , which most convincingly confirms 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 fossils. Scientists usually find petrified shells or bones, that is, skeletons, solid parts of organisms. Sometimes they find traces of the vital activity of animals or the imprints of their traces. Even less often, you can find the whole animal. They are found in the ice of permafrost, as well as in amber (resin of ancient plants) or in asphalt (natural resin).
Science paleontology
Paleontology is a science that studies fossil remains. Sedimentary rocks usually lie in layers, which is why deep layers contain information 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 us to draw conclusions about the directions of evolution.
Fossil record
If you look at the fossil record, we will see that life on the planet has changed significantly, sometimes beyond recognition. The first simple unicellular (prokaryotes) that did not have a cell nucleus appeared on Earth about 3.5 billion years ago. About 1.75 billion years ago, unicellular eukaryotes appeared. After a billion years, 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. Fifteen million years later, primitive vertebrates appeared that resemble modern lampreys. About 410 million years ago, maxillary fish arose, and insects - about 400 million years ago.
Over 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 cycas, as well as other groups of gymnosperms. The closer to our time, the more similarities are observed between fossils of fauna and flora with modern ones. This picture confirms evolutionary theory. She has no other scientific explanation.
There is various evidence for paleontological evolution. One of them is an increase in the duration of the existence of families and genera.
Increasing the duration 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, of which each is found exclusively in one or more neighboring 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 clan, in turn, has a strictly defined distribution. Scientists have found that childbirth lives tens of millions of years. As for families, their duration is estimated to be 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 evolutionary doctrine: gradually the most “hardy”, stable groups of organisms accumulate in the biosphere. They are less likely to die out because they better tolerate environmental changes.
There is other evidence of evolution (paleontological). By tracking the spread of organisms, scientists have obtained very interesting data.
Organisms spread
The proliferation of individual groups of living organisms, as well as all of them combined, also confirms evolution. Only the teachings of C. Darwin can explain their settlement on the planet. For example, in almost any group of fossils, "evolutionary series" are found. This is the name for the gradual changes observed in the structure of organisms, which gradually replace each other. These changes often look directed, in some cases we can talk about more or less random fluctuations.
The presence of intermediate forms
Numerous evidence for paleontological evolution includes the existence of intermediate (transitional) forms of organisms. Such organisms combine the characteristics of various species or genera, families, etc. Speaking of transitional forms, as a rule, they mean fossil species. 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 really existed (therefore, can be detected) and which cannot.
Currently, many of these predictions have come true. For example, knowing the structure of birds and reptiles, scientists can determine the characteristics of the intermediate form between them. It is possible to detect the remains of animals similar to reptiles, but having wings; or like birds, but with long tails or teeth. Moreover, it is possible to predict that transitional forms between mammals and birds will not be detected. For example, mammals with feathers never existed; or bird-like organisms with bones of the middle ear (this is typical for mammals).
Archeopteryx Detection
The paleontological evidence of evolution includes many interesting findings. The first skeleton of a representative of the Archeopteryx species was discovered shortly after the publication of the work of C. Darwin "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 of birds. However, the structure of the skeleton of this animal practically did not differ from dinosaurs. Archeopteryx had a long bony tail, teeth, claws on its forelimbs. As for the peculiarities of the skeleton that are characteristic of birds, he did not have a lot 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
Paleontological evidence of evolution also includes the discovery in 1856 of the first human skeleton. This event occurred 3 years before the publication of the Origin of Species. Scientists by the time the book was released did not know 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, which are transitional forms between chimpanzees and humans. This is important paleontological evidence of evolution. Examples of some of them will be given below.
Transitional forms between chimpanzees and humans
Charles Darwin (his portrait is presented above), unfortunately, did not find out about the many finds discovered after his death. He would probably be interested to know that this evidence of the evolution of the organic world confirms 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 chimpanzee’s brain, in the process of evolution, according to the theory, erect posture should develop over time. In addition, the brain volume was supposed to increase. Thus, one of the three transitional forms must have existed:
- large brain, undeveloped upright posture;
- developed upright posture, brain size like a chimpanzee;
- developing upright posture, brain volume is intermediate.
Remains of Australopithecus
In Africa in the 1920s the remains of an organism that was called 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).
Australopithecus inhabited northern and eastern Africa from 4 to 2 million years ago. They had a slightly larger brain than chimpanzees. The structure of the bones of their pelvis was close to human. The skull in its structure is characteristic of bipedal animals. This can be determined by the hole in the occipital bone that connects the cranial cavity to the spinal canal. Moreover, in the volcanic petrified ash in Tanzania, “human” traces were found that were left about 3.6 million years ago. Australopithecus, therefore, is an intermediate form of the second of the above types. Their brain is about the same as that of a chimpanzee, there is a developed upright posture.
Remains of ardipithecus
Later, scientists discovered new paleontological findings. One of them is the remains of an ardipithecus, who lived about 4.5 million years ago. After analyzing his skeleton, they found that the ardipithecus moved on the ground on two hind limbs, and also climbed trees on all four. They had poorly developed upright posture compared to subsequent hominid species (Australopithecus and humans). Ardipithecus could not move long distances. They are a transitional form between the common ancestor of chimpanzees and humans and Australopithecus.
Numerous evidence has been found of human evolution. We talked only about some of them. Based on the information received, scientists made an idea of how hominids changed over time.
Hominid evolution
It should be noted that so far, many are not convinced by evidence of evolution. The table with information about the origin of man, which is presented in each school textbook on biology, does not haunt people, causing numerous disputes. Can this information be included in the school curriculum? Should children study evidence of evolution? The fact-finding table resents those who believe that man was created by God. One way or another, we will present information on the evolution of hominids. And you decide how to relate to her.
In hominids, evolution was first formed by upright posture, and their brain volume was significantly increased much later. In Australopithecus, inhabiting 4-2 million years ago, it was approximately 400 cm³, almost like in chimpanzees. After them, the species Skillful Man inhabited our planet . His bones were discovered, whose age is estimated at 2 million years, more ancient stone tools were 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 larger. Its volume was 700-850 cm³. The next view, Homo erectus, was even more like a modern person. The volume of his brain is estimated at 850-1100 cm³. Then a view of the Heidelberg man appeared. His brain size already reached 1100-1400 cm³. Then came the Neanderthals, who had a brain with a 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 presented the basic evidence of the evolution of the organic world. How to relate to this information is up to you. The study of evolution continues to this day. Probably, in the future, new interesting finds will be discovered. Indeed, at present, such a science as paleontology is actively developing. Evidence of evolution, which it provides, is actively discussed both by scientists and people far from science.