Don't complain that northerners are tall. Too hot in the south is the biggest obstacle to height.

Recently, a research team from Cambridge University released a research report. They collected the measurement data of brain and body size of more than 300 Homo sapiens or family fossils.

There is a surprising discovery in the report that climate, especially temperature, has the greatest influence on human body.

In the past/kloc-0.0 million years, with the constant change of climate, the human body has undergone obvious changes.

The colder the climate, the higher the human body becomes; The warmer and wetter the climate, the shorter the human body will be.

Science Bulletin, an academic magazine affiliated to China Academy of Sciences, published a survey on the height of Han nationality in China.

In this report, the researchers measured the heights of 26,940 Han adults from 2009 to 2065,438+03, and analyzed the heights of 65,438+065,438+0 Chinese dialect adults.

The final data shows that people who grew up in the south are generally shorter than northerners.

The top three regions:

The following are the average heights of different age groups:

Young people aged 20-29:

People aged 30-39:

People aged 40-49:

People aged 50-59:

People aged 60-69:

No matter what age group, male or female, rural or urban, the average height ranks lower in Jiangxi, Guangdong, Hunan, Fujian, Hakka and Southwest dialect groups.

The hotter the temperature, the lower the height of people. Some netizens said: "I am short. Is it because I was born in the wrong place? "

/kloc-Bergman, a German biologist in the 0 th and 9 th centuries, described such a situation.

Bergman's Law: It points out that in the widely distributed taxonomic evolution, larger populations and species are found in colder environments, while smaller populations and species are found in warmer regions.

Mammals and birds are endothermic, and their weight will increase with the cold climate.

The same volume of endothermic animals should have different surface areas.

The bigger you are, the smaller your surface area is compared with your volume, so you can save heat more effectively in cold climates.

In a warm climate, the heat generated by human metabolism needs to be quickly dissipated rather than stored in the body.

Therefore, in the hot and dry climate, the ratio of the surface area to the volume of animals is higher, which is conducive to the loss of heat through the skin and helps the body to cool down.

The colder the climate, the higher the human body becomes; The warmer and wetter the climate, the shorter the human body will be.

This is why northerners are generally taller than southerners.

The process of human body change is a long process, and the measurement time is in thousands or tens of thousands of years.

Several years of climate change have little effect on our health. After all, changes in the human body cannot happen in a few years.

The height of adults is determined by innate genes and acquired environment.

Heredity determines our height, but the improvement of the day after tomorrow can also exert our genetic potential beyond our parents and families.

Physical exercise, adequate sleep and nutritious food (calcium, vitamin D and protein are the most important nutrients affecting human height) all contribute to improving physical fitness.

Moreover, northerners in China are much taller than southerners, which has something to do with their eating habits. Northerners eat more pasta, while southerners eat more rice.

The change of brain size has nothing to do with temperature, because the size of body and brain evolved under different pressures.

About 300 thousand years ago, Homo sapiens appeared in Africa. Compared with early species such as Hobbits, we Homo sapiens gained 50% weight and our brains were three times bigger.

This is because our ancestors lived in a more open habitat and needed to cooperate in hunting large mammals, carrying out more complicated work and domesticating animals.

More and more complicated social life, more diversified diet and more complicated technology may be the main driving forces of brain volume change.

Climate change has also made some animals on the earth smaller.

Through the analysis of 707 16 dead birds representing 52 species recorded from 1978 to 20 16, the researchers found that the size of 49 species of birds decreased significantly statistically.

In other words, in the past 40 years, migratory birds in North America have been getting smaller.

A study published in the journal Nature-Climate Change also shows that both aquatic and terrestrial exotics, such as toads, turtles and snakes, are shrinking with the increase of temperature.

The researchers also used fossil records, experimental and comparative evidence.

About 55 million years ago, during two relatively brief temperature rises during the Paleocene, the volume of animal fossils including beetles, bees and ants and other cave invertebrates decreased by 75%. Other fossil records show that animals, including kangaroos, wooden rats and California squirrels, have also shrunk during the past global warming period.

In the past 100 years, the global average temperature has increased by nearly 1 degree Celsius. Scientists predict that by 2 100, the temperature will rise to 7 degrees Celsius.

The current climate change is unlikely to have a big impact on our body shape for the time being, but global warming is an indisputable fact, especially the drastic climate change in the next 50 years.

In the future, human beings may face long-term physical changes and more and more extreme weather. Many areas where human beings live now are likely to become high-temperature deserts in the future.