There are many different species of animals on the earth, such as chimpanzees, gorillas, orangutans and other species in the orangutan family, while modern humans, although they have skin color, are all the same kind of humans, and there is no reproductive isolation. In fact, in the history of human evolution, there have also been australopithecus, Homo sapiens, Homo erectus, Flores, Homo sapiens and other human beings, but in the end only our Homo sapiens species has become the survivors of the evolution of human species.
From Australopithecus on the far right to modern humans on the far left, there have been many kinds of humans on Earth
As we all know, heritable variation is the intrinsic basis of species evolution, but it turns out that most of the heritable variation is harmful, because any kind of organism that exists tends to have a high degree of adaptability to the surrounding living environment, if a genetic mutation occurs, it is possible to destroy this adaptation relationship, such as the vast majority of human genetic diseases, which are caused by genetic mutations. Therefore, the "evolution" of randomness between species cannot be simply understood as "evolution" from low to high. Evolution due to geographical isolation is random, while evolution due to intraspecific struggle is the result of natural selection, which is the central concept of Darwin's theory of evolution, and the struggle for survival is the central content of Darwin's theory of natural selection, including (1) the struggle between organisms and nature; (2) interspecific struggle; (3) intraspecific struggle, these three aspects. Darwin attached the greatest importance to the question of evolution, the third of which was the intraspecific struggle. Intraspecific struggles are struggles between individuals of the same species for food, habitat, or other living conditions. The struggle between animals from within the species is often more brutal and fierce than the struggle outside the species, because life requires more competition between the same species of individuals, just like the competition of the same trade, the same kind of goods, Darwin believes that it is the combination of intraspecific struggle and biological variation that produces the survival of the fittest and causes the change of species.
Australopithecus and Homo sapiens are the ancient humans who were eliminated by Homo erectus in the intraspecific struggle, Homo erectus and other human animals live in the same way, the rise of the late ape Homo erectus must have led to the early ape man Australopithecus and Theophyllum living space was oppressed, so by about 1 million years ago, only the traces of Australopithecus and Homo sapiens that could be found were left with only remains. And just as Noh and Australopithecus were eliminated by Homo erectus, Homo erectus eventually had no way to escape the fate of being replaced by a new breed of Homo sapiens.
People from Heidelberg
The full name of "Homo sapiens" is "intelligent man", from the name it can be known that Homo sapiens has higher intelligence than Homo erectus, which is the last stage of human evolution, and the existing human beings belong to the Homo sapiens race. Heidelbergians are considered to be the ancestors of Homo sapiens, who evolved from The African Homo erectus- artisans about 700,000 years ago, mainly distributed in Africa and Europe; compared with the Peking Apes of the same period, Heidelbergians have basically lost body hair, and their brain capacity is 1100 to 1400 ml, much higher than Homo erectus (900 ~ 1200 ml), and the higher intelligence allows them to make more advanced tools. The Heidelberg people successfully installed wooden handles for tools and made the earliest long-handled tool of mankind, the spear. The earliest known spear was unearthed in South Africa 500,000 years ago and is a primitive weapon consisting of a wooden handle and a sharp stone blade. In addition to lengthening the attack range, spears can also be projected, which is conducive to hunting prey and is a huge advance in human tools.
700,000 to 550,000 years ago, the African Heidelberg people divided into two branches, the south branch of Heidelberg people remained in Africa to evolve new species such as Rhodesians; the north branch of Heidelberg people once again went out of Africa and divided into two branches, the east branch of which later reached Central Asia and the Far East and evolved into Denisovans. Denisovans are named after their discovery in denisova caves in the Altai Mountains of southern Siberia, and early Homo sapiens found in China, such as Shaanxi Dali, Liaoning Jinniushan, Guangdong Maba, Shanxi Dingcun and Xujiayao, have physical characteristics between Homo erectus and early Homo sapiens, but more characteristics are the same as early Homo sapiens, so some scholars believe that they may be the product of early Homo sapiens such as Denisovans and homo erectus in China According to the Ao Hong Research Group of the Institute of Earth Environment of the Chinese Academy of Sciences, the Xujiayao people in Shanxi and the Denisovans in Siberia have similar tooth characteristics, and they infer that the Xujiayao people may be the early Denisovans living in China.
Due to the scarcity and incompleteness of fossils, there is still no conclusive conclusion on whether there is a mixture of early Homo sapiens and Asian Homo erectus, and what is worse is that the global climate entered the Quaternary ice age 100,000 to 50,000 years ago, making it difficult for most organisms in other regions, including Chinese mainland, except for tropical regions such as Africa, to survive, known as the "Ice Age Species Extinction", and the number of ancient humans in China has also decreased dramatically, and even fossil faults have appeared between ancient humans and modern humans. At present, no human fossils dating from 100,000 to 50,000 years have been found in China, of which all fossils belonging to ancient humans have a history of more than 100,000 years, and the closest chronological distance is the skull of "Xuchang people" found in Xuchang City, Henan Province, which is about 125,000 to 105,000 years old, while most of the fossils of modern humans are less than 40,000 years old (mostly in 30,000 to 10,000 years), of course, the possibility that a small number of ancient humans native to China survived the Quaternary glacial period cannot be completely ruled out. Because the European Neanderthals, which evolved from the West Branch of the Heidelberg people, did not perish due to the cold of the Ice Age.
Neanderthals who lived in caves
Neanderthals are named after the Neanderthals valley found in Europe, Germany, and are also called cavemen because their fossils are found in caves at the mountains and valleys of Eurasia. Neanderthals are typical of early Homo sapiens (the ancients), whose remains are found throughout Europe and West Asia. The Moster culture they created is the most typical representative of the middle Paleolithic culture, which is characterized by the use of the technique of repairing stone cores, and the stone chips laid by the repaired stone cores can be used as tools without processing, which greatly improves the efficiency of stone tool production, which marks the beginning of the middle stage of Paleolithic. Neanderthals, who already knew how to sew clothes with crude bone needles to keep them cold, skewered animal bones and teeth into pendants, dyed with hematite and manganese oxide to create works of art, made luxury goods from crystals, and were the first to know how to bury the dead. In the caves and shacks inhabited by Neanderthals, traces of artificial fire are also found, from the use of natural fire to preserve fire, to learn to make artificial fire is a major leap in human intelligence, to know that to this day, the Pygmies in Africa, the Andaman people in India still do not manually make fire. Neanderthal brain volume averaged 1250 to 1750 milliliters, even larger than the modern human brain capacity (1300 to 1600 milliliters), but that doesn't mean they were smarter than modern humans, because their brain capacity was mainly reflected in the visual field, not the prefrontal part of the brain associated with the intelligent field.
As the perfect adaptor of the ice age human breed, neanderthal history runs through almost the entire ice age, but neanderthals as early Homo sapiens (ancients) can overcome the cold, but they cannot escape the fate of defeat in the intraspecific struggle and elimination. As late Homo sapiens (neo) from Africa entered Eurasia, Neanderthal sites began to decrement rapidly until they disappeared altogether.
Late Homo sapiens evolved from early Homo sapiens left in Africa, and its physique is basically indistinguishable from modern homo sapiens, and the oldest known remains of late Homo sapiens in the world are human fossils found in the Omo Valley in southern Ethiopia in East Africa, about 200,000 years old. Late Homo sapiens created the late Paleolithic culture, which was marked by standard stone tools excavated from East African sites and the first piece of well-preserved jewelry (bead necklace made of ostrich eggshells). From the emergence of capable people began to manufacture the earliest stone tools, human beings entered the Paleolithic Age, in the early up to 2 million years, human tool improvement is very slow, tool improvement is accompanied by the evolution of human physique, due to the backwardness of early tools, resulting in limited hunting ability, human beings still to collect as the main source of food. In the late Homo sapiens stage, human intelligence has made a new leap, and since then human technology is no longer linked to physique, and human history has entered a new stage. During this period, people knew how to make fish hooks, bone needles and other bone tools from easy-to-form bones, and used mammoth teeth and ribs to build a roof frame, and then covered with mammoth skin to build a mammoth hut. Stone tool making technology has a new development, the second processing of tools made of stone leaves accounts for a large proportion, a large number of composite tools and weapons with handles appeared, the method of grinding stone tools also appeared at this time, in addition to the emergence of harpoons, javelins, dart throwers, spear throwers, bows and arrows and other new tools, as well as ropes used to tie nets and make fishing lines, dogs were also domesticated by humans for hunting. With the improvement of hunting tools, humans can not only catch small animals, but also organize large-scale hunting groups to hunt mammoths, rhinos, bison, wild boar and other meaty and dangerous animals, and the hunting era has arrived.
The prehistoric behemoth saber-toothed tiger that was wiped out by mankind
Modern scientific research believes that modern humans who are good at hunting are an important cause of the global mass extinction at the end of the Ice Age, and it is true that the sudden change in climate led to the extinction of a large number of species at the beginning of the Ice Age, but most of the organisms that can survive until the end of the Ice Age have been able to adapt to the cold climate, and their extinction is caused by human over-hunting. On the one hand, they were hunted directly by humans, and on the other hand, because their food was hunted by humans, such as the saber-toothed tiger, the largest prehistoric cat, which was extinct. About 40,000 years ago, a group of modern humans entered The Neanderthal stronghold of Europe, and they were the earliest modern Homo sapiens in Europe found in the Crocopian Caves in France- the Croplasmmen. The fossils of Cro-Romanon are also the world's earliest complete late Homo sapiens (neo)fossils, so late Homo sapiens is often collectively referred to as Cro-Romanon, and Europe is the richest place for late Homo sapiens sites. From the remains of the European Croma nong, it can be seen that this group of newcomers who entered Europe was tall, burly, strong, and the average male body was more than 1.8 meters high, with hunting as the main food source, and they entered Europe and swept through neanderthals from east to west, and finally became completely extinct.
Whether cromerons were mixed with Neanderthals during their extermination has always been a hot topic in anthropological research, neanderthals are the most recent evolutionary relatives of modern humans, and have been separated from the ancestors of modern humans for no more than 500,000 years, so there should be no reproductive isolation between the two. In a new issue of Science published on May 7, 2010, a sequence map of about 60 percent of neanderthal genomes was published, and an international team of scientists led by Svant Pab, a scientist at the Max Planck Institute for Evolutionary Anthropology in Germany, compared Neanderthal genes with the genomes of modern humans and found that modern humans other than Africans had 1% to 4% common genes with Neanderthals, suggesting that the ancestors of modern humans may have been mixed with Neanderthals on a small scale. In 2012, scientists sequenced the genomes of Denisovans living in Central Asia and the Far East, and the results showed that as many as 5 percent of some modern human genomes come from Denisovans. It can be seen that although early Homo sapiens such as Neanderthals and Denisovans were extinct from a species point of view, their bloodlines were still passed down.