Humans became omnivores
Humans have a very flexible digestive system that allows us to digest a wide variety of foods. Compared to other animals, humans have a relatively long intestine, creating a good environment for us to digest complex carbohydrates. In addition, in the mouth there are some digestive enzymes such as amylase and protease, which help us digest foods rich in starch and protein more effectively. These properties allow us to obtain nutrients from a variety of foods.
Illustration. Photo: Missionblue
Human tooth structure adapts to different types of food. We have many different types of teeth, including sharp incisors and pointed canines as well as molars. These specialized tooth structures allow us to cut, bite, and grind different foods. The incisors and canines are suitable for grinding foods such as meat, while the molars and back molars are suitable for chewing plant fibers and hard foods.
Humans have also developed advanced intelligence and tool use, giving us enormous advantages in gathering and processing food. We can use tools to craft and use various hunting and gathering tools, such as bows and arrows, nets, fishing gear, etc., to collect and fish for animal resources. animals and plants. At the same time, we can also change the properties and flavors of food through cooking, processing and baking. This allows us to better utilize the nutrients provided by plants and animals.
Human adaptations to food are also related to culture and environment. Different regions and ethnic groups have different preferences and eating habits. For example, some peoples have plant-based diets, such as rice and beans in Asian countries, while others have meat-based diets, such as salmon and beef. in Nordic countries. This diverse food choice is also the result of humans adapting to a variety of environments and resources.
Illustration. Photo: Zhihu
The impact of natural disasters on human evolution
Natural disasters can promote the development of human adaptability and survival skills. In the face of natural disasters, people are forced to adapt quickly and improve their ability to survive and escape. This strong adaptability is important in biological evolution. When faced with natural disasters, humans are forced to improve their ability to observe and respond to crises, and develop more sensitive cognitive mechanisms and more effective survival strategies.
For example, after thousands of years of regularly facing floods, humans chose to build cities on water and floating ships to cope with the threat posed by floods. This long process of adaptation has driven the advancement of human civilization and shaped the way we live today.
Natural disasters also have important impacts on social aspects of human evolution. In the face of large-scale disasters, people must unite to solve difficulties together. Cooperation and social cohesion have become key factors for human survival and recovery.
Natural disasters force people to come together and solve problems together. This promotes the formation of a sense of community, strengthening relationships and the development of human society. The occurrence of some natural disasters in history such as earthquakes and floods has motivated people to cooperate in building fortresses and together fight against natural disasters. These collective efforts have reshaped the fabric of our society, emphasizing the importance of teamwork and mutual support.
Illustration. Photo: Missionblue
The ultimate impact of natural disasters on human evolution is at the genetic level. According to new research, individuals of some human groups that survived natural disasters in history often had genetic mutations that adapted them to disaster environments. These mutations can make individuals more resilient and adaptable to disaster environments. Over time, these genes have been genetically passed on to future generations, thereby enhancing overall human resistance.
For example, in areas where malaria is common, genetic variants that are resistant to malaria parasites gradually dominate the population, making people in these areas more resistant to malaria. Such gene transmission mechanisms are important to human evolution. Human groups that successfully inherit adaptive genes are more likely to survive in the face of future natural disasters.
The relationship between the human digestive system and omnivorousness
Our mouth and teeth are the starting point of the digestive system. Human teeth have different shapes and functions, including sharp incisors, sharp canines, and hard molars. These special teeth help us chew many different types of food. Our incisors are used to crush food, our canines are used to chew meat, and our molars are used to grind plant fibers.
Illustration. Photo: Zhihu
Our mouth also contains salivary glands, which contain a digestive enzyme called amylase, which breaks down starch into sugar. Amylase begins to work when we chew foods that contain starch. This also explains why when we eat bread or rice, we feel the food tastes sweeter.
Food then passes through the throat into the esophagus and then into the stomach. The stomach is a highly acidic organ, secreting gastric acid and digestive enzymes to break down food. The presence of these digestive acids and enzymes allows the stomach to digest a variety of foods, including meat, vegetables, and fruits. The acidic environment of the stomach helps kill bacteria and viruses hidden in food.
Next, the digestive system pushes undigested food into the small intestine. In the small intestine, food is broken down and absorbed more deeply. The inner wall of the small intestine has many small villous structures called “intestinal villi”, which significantly increase the absorptive surface area of the small intestine. The presence of this structure facilitates the absorption of nutrients, including carbohydrates, fats and proteins.
Illustration. Photo: Zhihu
Finally, unabsorbed food particles enter the large intestine. The large intestine mainly absorbs water and salt and converts food waste into stool. During this process, some vitamins K, B and other beneficial substances can be produced.
Due to the omnivorous nature of the human digestive system, we have access to a wider variety of nutrients and are better able to adapt to changes in the environment and food supply. It is also one of the important factors in the evolutionary success of our species.
The reason humans became omnivores is the result of a combination of many factors. According to the study, large-scale environmental changes occurred on Earth at that time, leading to the extinction of many plant species and disruptions in the food chain. Humans during this period faced serious survival challenges and had to adapt to new food sources, including animal meat and other food sources. As a result, humans quickly adapted to omnivorous eating, which became one of the important milestones in our evolution.
