As scientists continue to explore our evolutionary history, there are new facts that explain how the past shapes the modern people, the size of our brain to the length of life. Even more intriguing is the role played by chance in the formation of the brain and body, which have a modern people.
1. The human person is formed to sustain udar
Until recently it was widely believed that the strong human faces formed about four to five million years ago, to help our ancestors Australopithecus chew solid food, such as nuts. But now it is destroyed by a direct blow to the view in person.
According to a study at the University of Utah, our distant past was not as peaceful as we once thought. Probably, violence played a much greater role in the development of human physiology than we suspected before. Researchers believe that men's faces are formed in such a way as to minimize injuries from blows during fights for women, food and territory. Facial bones become stronger, so as not to break during the melee. These bones represent the difference between male and female skulls. Obviously, male individuals had to evolve in such a way, because the bones breaking in combat, men are larger.
If this theory is correct, people were not noble savages, who became aggressive because of the civilization. Instead, our physical ability to develop, to improve our fighting force.
2. Human hands developed for application udarov
While human faces formed to withstand the blow, our hands are formed for its application. In an earlier study of the same University of Utah scientists discovered that human hands formed paradoxically. In comparison with the monkeys, the same features that allow us to clench his fists - short four fingers and the palm at a long, strong and flexible thumb - also give us agility to make and use thin instruments. But while the chimps can make tools, they can not clench his fists.
It is also possible that our hands have evolved from the same gene, which gave us a short toes and elongated thumb, when we started to walk and run in a vertical position.
Scientists believe that our aggressive and violent nature made our bodies turn into fighting machines. A man stabbing a clenched fist can hit harder, do not hurt yourself. Fists can also be used to intimidate. Ultimately, our hands - with their ability both to kill and to create - can be divided between good and evil in human nature.
3. We had herpes before we became lyudmi
Some of our physical characteristics not just developed over time. Some diseases, such as herpes, came to us from the chimpanzees.
Approximately 67% of the modern people have at least one herpes simplex virus (HSV). In fact, people - are the only primates that have two HSV usually manifested in the form of herpes blisters on the lips or in the genital area. Herpes first type affected people before they split from chimpanzees about six million years ago. HSV second type to us from chimps about 1, 6 million years ago. Scientists from the University of California believe that the study of the origin of these viruses will help prevent the transition to people of other diseases.
Another group of scientists from Oxford and the University of Plymouth found ancient viruses Neanderthals in modern human DNA. These viruses come from a family of HML2 and can be linked to cancer and HIV modern man. This information may be useful in the future for the development of therapies.
4. Man - the only primate teeth whose size decreases with increasing size mozga
During the last 2 to 5 million years were linked two trends of human development - the size of the human brain increased and decreased the size of the teeth. We - the only primates that can boast.
Normally when the brain is growing, growing and teeth, because the body needs more energy from food. Therefore, scientists call what happened to the people, an evolutionary paradox. They believe that it occurred because of the fact that people are eating more meat, which nourishes our brains.
Also, the people - the only primates who have developed thick tooth enamel. In herbivorous primate tooth enamel is thin, in higher primates and monkeys that eat both plants and animals, enamel of medium thickness. People enamel even more fat, probably hard to push products. Scientists human enamel can also determine the age and diet of ancient people of human fossils.
But Neanderthals - the earliest hominids enjoyed toothpicks to ease the pain of dental diseases such as sore gums.
5. Our common male and female ancestors lived about the same vremya
Researchers often use the name of «Y-chromosomal Adam" for our most recent common ancestor. Males usually have one X-chromosome and one Y-chromosome, women - two's X-chromosome.
According to a study published in the "European Journal of Human Genetics," "Adam" probably lived about 209 thousand years ago.
This model is contrary to previous research of the University of Arizona, suggested that the Y-chromosome existed before the origins of humanity. Scientists from Arizona believed that the Y-chromosome modern men have been created by crossing species more than 500 thousand years ago. But a new study claim that the Arizona study, if properly interpreted, creates a "space-time paradox, according to which the oldest individual, belonging to mind Homo Sapiens, not yet born».
The new study also puts a Y-chromosome, "Adam," in the days of "Eve" of the nearest female common ancestor of modern humans. However, scientists say that there was no one "Adam" and one "Eve" - instead of them were groups of "Adam" and "Eva", roaming the world.
6. Grandparents help us live dolshe
Grandma made us who we are. This conclusion was made by scientists from the University of Utah, who ran computer simulations to test the famous "grandmother hypothesis". According to this evolutionary theory, humans duration of life more than the apes because grandmothers helped feed their grandchildren. Other primates themselves looking for their own food after weaning.
When human grandmother began to help feed their grandchildren, mothers were able to have more children. The simulation showed that the evolution of the women who die immediately after child-bearing age, living up to a decade after menopause took 60 thousand years.
Many anthropologists believe that the increase in the size of our brain to an increase in the duration of our lives. However, researchers from the Utah controlled by brain size, hunting and making pairs in computer modeling. When they entered a minimal effect on the presence of her grandmother, the human life span has increased dramatically. Scientists came to the conclusion that my grandmother helped - or caused - such important changes in human evolution, brain development as a larger social dependence and our inclination to work together.
7. The protein may contribute to the development of the brain more razmera
Researchers from the University of Colorado has another theory about why the human brain evolved so quickly to such a size and complex system. These scientists found that the protein domain, which is a specific unit of the protein structure, in more common in humans than in animals. This protein domain DUF1220, and what it is, the more your brain. People in the genome there are 270 copies, followed by the chimpanzees and gorillas from 125 to 99 copies. In mice, there is only one copy. This means that the brain size may vary depending on the amount of protein domain.
Also contributing to the development of large brain have difficulty finding rare insects for food, which required the development of problem-solving skills and tools. But a larger brain size was not the only factor in the evolution of the human primate - people are also more complex genetic activity that helps in training.
8. Throwing made us lyudmi
Skills throwing modern baseball evolved from our extinct human ancestors. Early humans learned to throw stones and sharpened wooden spear while hunting almost two million years ago. According to scientists from George Washington University and Harvard University, even a chimpanzee can not be compared with the people in these skills. Chimpanzees can at best throw only one-third as fast as the 12-year-old Little League pitcher.
The researchers wanted to find out why people throw so well. While watching the recording baseball games, scientists realized that the human arm works like a slingshot, maintaining and releasing energy during the throw. Some features of a human torso, shoulder and arm specially developed to help us to store this energy.
Throwing skills have allowed our ancestors to kill and eat the big game. Eating meat has stimulated the development of the human body and brain to large sizes. So unique ability to throw our ancestors helped us become men.
9. The duration of a person's life may be associated with a very slow exchange veschestv
Humans and other primates burn on 50% fewer calories than other mammals. This means that to burn as many calories are burned as other mammals of the same size in a day, a person will have to run a marathon.
According to a new study, to explain why we are growing so slowly, so rarely have children and live so long, can we slow our metabolism. It may also explain why we have developed so many different programs for weight loss. But if you exercise, and you have problems with weight loss, the study can also point you to the cause. It was also found that the primates in cages at the zoo to spend as much energy as their counterparts in the wild, and this in turn means that physical activity is likely to affect the amount of burned daily calories less than we thought.
For comparison, the majority of mammals, such as our domestic dogs or hamsters, quickly go through all stages of life and early death - often after a decade or earlier. Scientists believe that environmental conditions have affected the development of a slow metabolism, which gives us long life.
10. irony that influenced the human evolyutsiyu
Scientists from the University of Chicago are engaged in "molecular time travel 'to see how human evolution could have gone differently. They started with an important protein in the human body as it existed hundreds of millions of years ago. This protein, eventually became the cellular receptor for the stress hormone cortisol.
Biologists want to know how this ancient protein became sensitive to cortisol. After studying thousands of alternate versions, they found only one answer - it was an accident. It should have happened two extremely rare mutation, so that the protein could develop sensitivity to cortisol. In other words, the modern form of the protein occurred due to chance in our distant past.
Researchers believe that a series of unlikely chance events - irony - effect on proteins that have made us who we are. If the proteins will develop new features can be explained by the diversity and genetic diversity of life. It also means that when some other circumstances people could turn into something completely different.