Some species of water bears are known to eat entire live organisms, such as rotifers and other tardigrades. Typically, tardigrades are dioecious, that is they have male and female individuals in the population. The presence of dwarf males or no males has been reported in some populations. Fertilization can occur through a gonopore or the male can deposit his sperm on the eggs after they have been laid either on the substratum or in the molted cuticle. Females lay from 1 to 30 eggs at a time.
Tardigrades express eutely, which means that the number of cells in the body is fixed from birth.
The wide spread distribution of tardigrades can be attributed to the fact that their eggs, cysts, and tuns are light enough to be distributed by wind or animals for great distances. Back to the top Cryptobiosis One way in which tardigrades have adapted to various types of environments, has been to reversibly suspend their metabolism. This state is known as cryptobiosis and is a truly deathlike state. The most intensely studied type of cryptobiosis is anhydrobiosis, a form of cryptobiosis initiated by desiccation. Living in a limnoterrestrial habitat, such as moss, requires that these organisms can survive periods of dryness.