You can refer to the following steps to draw a sad crayfish:

Draw a semicircle as the head of the crayfish. Draw two small circles under the head as eyes. Draw two short lines under the eyes as its tentacles. Draw two short lines above the head, and then draw a small circle on each short line as its ears. Draw an arc and two small circles under the head as its feet. Draw an arc and two small circles behind the foot as its other foot.

I. Historical Origin

The history of crayfish can be traced back to America, especially in some rivers and lakes in Mexico and the southern United States. The name of this aquatic product comes from French, which means "shrimp". As early as the 19th century, crayfish became a special ingredient in French cuisine. In China, crayfish also has a long history of eating, especially in the Yangtze River valley in the south of the Yangtze River, which is regarded as one of the delicacies.

II. Growing environment

Crayfish is a benthic freshwater organism, which usually grows in freshwater rivers, lakes and streams with appropriate temperature and clear water quality. In their growing environment, water quality and water temperature play a vital role. Usually, the water temperature should be kept between 15℃ and 25℃, while the water quality needs to be kept clear and pollution-free. In addition, crayfish also need sufficient sunlight and oxygen to maintain life activities.

Third, the impact on human health

Crayfish is a kind of nutritious aquatic products, which contains a lot of protein, trace elements, unsaturated fatty acids and other nutrients beneficial to human health. Eating crayfish in moderation can promote human health, such as enhancing immunity and lowering cholesterol. In addition, crayfish also contains some minerals and vitamins beneficial to human body, such as calcium, phosphorus, vitamin A and so on.

However, crayfish may also contain some harmful substances, such as heavy metals and bacteria. If the growing environment is polluted, crayfish may accumulate a lot of heavy metals, such as lead and mercury, which will have a negative impact on human health. In addition, if crayfish grow in an environment with poor sanitary conditions, it may also be contaminated by bacteria, leading to food poisoning after eating.

Generally speaking, moderate consumption of crayfish is beneficial to human health, but attention should be paid to the source and hygiene. It is suggested to choose regular channels to buy tested crayfish and ensure that they are fully cooked in the cooking process to avoid food safety problems. At the same time, people with allergies should also pay attention to the allergy test before eating to ensure safety.