Earth is the only living planet known to mankind, and it took 4 billion years from a patch of dust to the appearance of humans. Do you know what stages life has gone through in these 4 billion years before it evolved into the current human being?
The cutest planet
Early life
The first life appeared 4 billion years ago.
Prokaryotes similar to cells appeared 3.9 billion years ago.
Organic biology used oxygen 2.5 billion years ago.
More complex eukaryotes emerged 2.1 billion years ago.
The ability of organisms to evolve sexual reproduction 1.2 billion years ago triggered an acceleration in the rate of evolution.
600 million years ago, the first multicellular animals appeared, generally considered similar to sponges.
550 million years ago, flat animals appeared, they are the first animals to have brains, and they are also the simplest animals with existing morphological symmetry. At the same time, they are the simplest animals with organs.
chordate
530 million years ago, Pikalars were the earliest known ancestors of chordates. It is believed to be the earliest animal with a chord and is also the ancestor of vertebrates.
The earliest vertebrate beetle appeared 505 million years ago, a palatineless fish similar to today's eight-eyed eel and hagfish.
The Titalik, which lived in the late Devonian period 375 million years ago, is a species belonging to the general order of finned fish, and some tetrapod characteristics have emerged.
quadruped
365 million years ago, some species of the general order of finned fish evolved legs, which led to the emergence of tetrapods. They first appeared in freshwater habitats in shoals and swamps.
A 315 million-year-old axorupt was an extinct amphibian and was the first to have recognizable limbs. They are also thought to be the earliest vertebrates with the ability to live on land.
Amphibians evolved into reptiles 300 million years ago. Reptiles learned to reproduce on land and lay eggs on wetlands without having to return to the water to reproduce, which also brought their footprints to the highlands.
mammal
Soon after the emergence of reptiles 256 million years ago, they evolved into two branches. An evolutionary branch became the dipteropoda ( belonging to the lizard order ) , which became what is now a reptile. The other is the homophthalmie, which soon evolved into theophora, which is the direct ancestor of mammals.
More mammalian traits evolved 220 million years ago in the suborder Cannithopods, a branch of the order Thermomyopae. The lower palate of the canines is similar to that of modern mammals and is therefore probably the direct ancestor of all modern mammals.
125 million years ago Archaeopteryx was a mammal of the order Euptyopsis and the ancestor of placental mammals. They resemble modern sleeping mice, and fossils have been found in Liaoning, China.
A common ancestor of rats and humans appeared 100 million years ago.
Primates
Between 65 and 85 million years ago, a small, nocturnal, tree-dwelling, insect-feeding primate emerged, and they evolved into later primates, tree shrews, and dermatophylls. Simpson's fruit monkeys are one of the last more anthic animals, and they already have toes that can grasp things, but their eyes can't look forward yet.
The Messel Darwin monkey was a transitional form between the suborder Lemur (including lemurs and other primitive primates) and the lower order of great apes (including monkeys and apes) 47 million years ago. Similar to lemurs, but with a thumb.
Primates evolved 40 million years ago into the proto-monkey suborder and the suborder Sacral suborder.
30 million years ago, the two evolutionary branches of the suborder Jane's nose were broad-nosed suborder and narrow-nosed suborder.
25 million years ago, the narrow-nosed order evolved into two general families, namely the monkey family (Old World monkey) and the ape family (ape).
Humanities
The anthropocene was separated from the ancestors of the gibbon family 15 million years ago.
The human subfamily was separated from the ancestors of the orangutan subfamily 13 million years ago.
The Terrans separated from the ancestors of the Gorillas 10 million years ago.
The human subgenus separated from the ancestors of the chimpanzee subfamily 7 million years ago, and the most recent common ancestor of the two lived in this era.
4.4 million years ago, the ape belonged to the early genus of the human subfamily, with two species. One is archaeopteryx, which lived in the early Pliocene 4.4 million years ago, and the other is Kadabadi ape, which lived in the late Miocene 5.6 million years ago.
3.6 million years ago, in Letori, Kenya, footprints of bipeds left in volcanic ash were found, and the owner of these footprints was the Australopithecus arfa. They lived about 3.9-2.9 million years ago and are thought to be the common ancestor of australopithecus and man.
A probable ancestor of the genus Mannes 3.5 million years ago, the Kenyan Flat-Faced Man, appeared.
The bipedal Australopithecus appeared in the African savannah 3 million years ago.
Evolution from life to humanity
Genus Human
A human species appeared 2.5 million years ago. Stone tools appeared, beginning in the early Paleolithic period.
Homo erectus appeared in Africa 1.8 million years ago. Homo erectus has a large degree of similarity with modern humans, but the brain volume is only 74% of that of modern humans. They have a flatter forehead and smaller teeth. The Grudeans, craftsmen, Pekingese, and Heidelbergers are sometimes considered homo erectus in the broad sense.
1.5 million years ago, homo ergasters learned to use fire. They are about 1.9 meters tall.
Beijingers first appeared in Asia 700,000 years ago. But according to the origin of the single land, they are not the ancestors of humans, but only the collateral species of craftsmen.
Homo antecessor 516,000 years ago was the common ancestor of humans and Neanderthals. By current estimates, humans have 20,000-25,000 genes and 99 percent identical DNA to extinct Neanderthals.
The footprints of three 1.5-meter-tall Heidelbergers were found in volcanic ash in Italy 355,000 years ago. They are the common ancestor of Neanderthals and humans. Morphologically similar to Homo erectus, but with a larger brain volume, about 93% of modern humans. Their average height is 1.8 meters, which is more robust than modern humans. Beginning in the middle of the Paleolithic period.
The remains of Omo, discovered 195,000 years ago in the Omo River in Ethiopia, are the earliest fossil evidence that ancient Homo sapiens evolved from Heidelberg man.
160,000 years ago, the elder homo sapiens in present-day Ethiopia had a funeral rite and learned to slaughter hippos.
150,000-year-old front-line granulosa Andeva lived in East Africa. She is the most recent common ancestor of all living humans (mitochondrial genes are inherited maternally).
70,000 years ago the anterior mitochondrial haplogroup L2 appeared, with behavioral modernity.
60,000 years ago Adam Y lived in Africa. He is the most recent common ancestor of all living humans (the Y chromosome gene is inherited through the paternal line). Mitochondrial haplogroups M and N emerged, and they were involved in the process of migration out of Africa.
Migrated to South Asia 50,000 years ago. The M168 mutant appears (carried by all men outside Africa). The late Paleolithic period began. Mitochondrial haplogroups U and K appear.
Migrated to Australia and Europe (Cro-Romanon) 40,000 years ago.
Neanderthals went extinct 25,000 years ago. Y chromosome haplogroup R2, mitochondrial haploid group J, and X appear.
The Holocene and Mesolithic periods began 12,000 years ago. Y chromosome haploid group R1a, mitochondrial haploid group V, and T appear. Europeans evolved a pale complexion (SLC24A5 gene). The Florestins became extinct, and Homo sapiens became the only surviving species in the genus Homo sapiens. Homo sapiens of this period are modern humans.
What is the concept of the 12,000 years of modern man's emergence compared to the 4 billion years of the evolutionary history of life? If life has evolved for 1,000 years, then we modern people have just been born for one day, and new China has only been born for 8 minutes! Cherish time, because life is so hard to come by, but it is so short.
Future humanity
Will humans still evolve? What will the people of the future look like?
Ernst Meier believes that, first of all, it is impossible for humans to divide into several species. Because humans occupy all the ecological stoves that can be imagined. Moreover, there is no geographical segregation in the population. Today, interactions across all populations are too frequent to form any form of long-term effective isolation that could lead to adult events. He also believes that the existing human species can no longer evolve into a "better" species, and will not become superhuman. Because although there are indeed genetic variants in human genotypes that can be used as appropriate selection materials, the conditions are different from those in which Homo erectus evolved into Homo sapiens. Modern humans constitute a large society, there is no sign of any natural selection that can screen for superior genotypes, and as the choices that play a role of improvement no longer function, there is no chance of evolving a more superior human species.
Unlike the evolutionary theory of natural selection, many people, like Hawking, believe that human genetic engineering, this kind of information transmission through external non-biological means that puts humans above the world and increases the population exponentially, so that we can increase the complexity of our internal record, that is, DNA, without waiting for the slow steps of biological evolution, and in the last millennium we are likely to completely redesign DNA and create improved human races.