The separation of Homo sapiens from gorillas and chimpanzees occurred approximately

The earliest humans, including Saher, Protoll, and ape. Walking upright on two legs is the main mode of movement, and it is also adapted to climbing in trees. These species live in from.

Six or seven million years ago to 4.4 million years ago.

The separation of Homo sapiens from gorillas and chimpanzees occurred about 4 million years ago.

Humans and chimpanzees share a common ancestor, and millions of years ago, they began to evolve in different directions. Previously, scientists generally believed that humans and chimpanzees could be between 5 million and 7 million years ago"Separation"。However, according to Reuters 23**, a new study believes that the divergence between humans and chimpanzees occurred 4 million years ago, and the academic community has mixed opinions on the results of this study.

By comparing the genomes of humans, chimpanzees, and gorillas, Houbbos et al. found evidence that the divergence between humans and chimpanzees occurred about 4 million years ago. The findings were published in the latest issue of the journal PLoS Genetics.

"Assuming that orangutans formed 18 million years ago, then the divergence of humans and chimpanzees should be about 4 million years ago," Hough et al. point out in **. "Because earlier studies have confirmed that humans and chimpanzees evolved more slowly than gorillas and orangutans, it is imperative that humans were separated from chimpanzees and became separate species later than orangutans and gorillas formed.

Earlier studies have confirmed that humans and chimpanzees "separated" millions of years ago, and scientists generally agree on this. However, it is quite difficult to determine the specific time of "separation". Scientists have different opinions on this and have not been able to reach a consensus.

The research results of Houbos et al. have postponed the "separation" of humans and chimpanzees by more than 1 million years.

Commonalities between humans and chimpanzees: thumb and index finger opposite; unique expressions of joy, anger, sadness and happiness; The structure of the bones is the same. It shows that humans and chimpanzees are closely related and have a common ancestor, Australopithecus forest, which evolved.

The differences between humans and chimpanzees are: 1) Different modes of movement. Great apes are predominantly armed; Humans, on the other hand, walk upright.

2) The ability to make tools is different. Great apes can use natural tools, but they can't make them; Humans can make and use a variety of simple and complex tools. (3) The degree of brain development is different.

The ape-like brain has a capacity of about 400 ml and has no ability to speak and write; The human brain has a capacity of about 1 200 ml and has strong thinking and writing skills.

b Parse The passage begins with a common problem among thinkers, which is that chimpanzees are regarded as monsters. This leads to a different point of view, which is the subject of this article: "For an evolutionist, this is not the case." There is no objective basis for believing that one species is nobler than another", and the last sentence is used to explain the reason for the topic sentence, because all species evolved by natural selection, and the implication is that all species should be treated equally, so the correct answer is item b.

Common Misconceptions Item C only mentions the reason and does not address the main points of the topic. AD is clearly not the author's stated intention.

Answer: c

The "belief that one species is nobler than another is without any objective basis" directly refutes the claim that most thinkers see themselves as the masters of all things, and then gives an example that "chimpanzees and humans, lizards and fungi have all evolved through a process of so-called natural selection that has lasted for 3 billion years." ”

There are four types of "great apes" in the world: orangutans (also known as yellow apes), gorillas, chimpanzees and bonobos. Chimpanzees are primate great ape mammals.

Recently, scientists from the Georgia Institute of Technology, the National Human Genome Institute and other institutions published a study in the Proceedings of the National Academy of Sciences, showing that among all primates, chimpanzees have the smallest differences with humans, chimpanzees and humans are more closely related to them and other apes, and chimpanzees and humans are the slowest primates with the molecular "evolution clock". Yi Sujin of the Georgia Institute of Technology, who leads the research team, believes that the new discovery has once again brought chimpanzees closer to humans, who can be called "brothers" and "cousins" with orangutans and gorillas

Yi Sujin and other researchers compared the genome sequences of several primates such as humans, chimpanzees, gorillas, and orangutans, and compared the operating rate of their "evolutionary clock", that is, the rate of single nucleotide mutation in the genome. The researchers found that among all primates, the human "evolutionary clock" is the slowest to run, that is, the human genome has the least single nucleotide variation, the genome is the most stable, and the chimpanzee "evolutionary clock" runs only slightly faster than humans, but it is significantly slower than larger orillas and orangutans, the human "evolutionary clock" is about 11% slower than the gorilla, and the chimpanzee's "evolutionary clock" is about 8% slower than the gorillaThe study's lead participant, Ilango of the Georgia Institute of Technology, believes that in the evolutionary history of primates, the common ancestors of humans and chimpanzees may have "separated" from the ancestors of orangutans and gorillas, causing the "evolutionary clock" of both humans and chimpanzees to slow down, and then humans and chimpanzees diverged.

Based on the comparison of genetic sequences, it can be inferred that about 25 million years ago, the ancestors of apes separated from other primates; 14 million years ago, the common ancestors of gorillas, chimpanzees, and humans separated from their orangutans; 6 million 7 million years ago, the common ancestor of chimpanzees and humans separated from the ancestors of gorillas; 5 million 6 million years ago, the ancestors of chimpanzees separated from their human ancestors. The ancestors of chimpanzees went through an independent evolutionary process after they were separated from their human ancestors.