The body is segmented without division, the wart foot degenerates, and the body surface has bristles. Androgyny, with 1-2 pairs of gonads, the reproductive duct originated from the body cavity. When sexually mature, there is an annular band on the body surface, which can fertilize each other during mating. Eggs are produced in the girdle, and form cocoon after shedding, which develops directly.
Extended data;
Earthworms like to live in a warm and humid environment, but different kinds of earthworms have different living habits and lifestyles in different regions and seasons.
1, humidity
Earthworms have a water content of 70%-80%, and maintain balance by secreting body fluids on weekdays. Therefore, they must live in a humid environment. The humidity adaptation range is 30%-80%. For example, the suitable humidity of earthworms is 30%-45%; Eisenia foetida (red earthworm) is suitable for 50%-80% humidity.
This habit of earthworm makes it in a state of digging holes and nesting. High humidity or low humidity environment is not conducive to its normal survival. When the humidity is lower than the limit, earthworms will dehydrate, shrink extremely, be in a semi-dormant state or die. On the contrary, it will die with the increase of temperature.
2. Temperature
Earthworms are warm animals and are very sensitive to temperature changes. When the temperature drops to 10C, earthworms stop eating. When it drops to 4℃, it goes into hibernation; It will freeze or die below 0℃. Generally large and medium-sized earthworms live in underground caves for the winter; However, most small earthworms gather together and gather in warm soil for the winter.
Climb to the surface when the temperature rises to 8- 10℃ in the second year. The survival rate of weak and atrophied earthworms is low, and it is difficult to live through spring. When the temperature exceeds 30℃, the growth is also inhibited, shrinking rapidly and the body color changes deeply, and it is stuck in deep soil.
When the temperature is above 35℃, it will completely stop eating and enter a dormant state, and the earthworm will completely shrink and feel extremely dull. Once the temperature drops, it can be restored to its original state. The optimum temperature is 20-25℃ ..
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