Characteristics of the Tardigrada

Characteristics of the Tardigrada:

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HABITAT
Where they are found

SCIENTIFIC STUDY
General Biology
Ability to Adapt
Reproduction

1) Bilaterally symmetrical.
2) Body has more than two cell layers, tissues and organs.
3) Body cavity is partially a coelom.
4) Most possesses a through straight gut with an anus.
5) Body monomeric.
6) Body possesses 4 pairs of unjointed claw bearing legs.
7) Body possesses a fixed number of cells (eutelic).
8) Has no circulatory or respiratory system.
9) Primitive excretory organs in some species.
10) Reproduction normally sexual and gonochoristic, but can be parthenogenetic.
11) Feed on a plants or small animals.
12) All live in aquatic or damp places, normally associated with vegetation.

Data from: www.earthlife.net/inverts/tardigrada.html

What can they do

Apparently, resent research shows tardigrades can resist 6000 atmospheric pressure. That’s nearly 6 times the pressure of the deepest ocean water. Tardigrades can survive temperatures as low as -272 which is colder than the atmosphere in outer space, or survive at -200 for more than 2 weeks. Other species of tardigrades can survive further punishment such as temperatures as high as 125c, and others can survive major doses of x-rays more than 245 times greater than that which would kill a mammal or any other animal for that matter. They are the only animals that can survive having their photo taken in an scanning electron microscope which involves placing them in a vacuum and then bombarding them with electrons. Probably the most amazing thing about them is the fact that they can go into a stage called cryptobiosis. Cryptobiosis is the sate in which water bears can reversibly shut their metabolism and effectively isolate themselves from everything. This ability is truly a close death-like-state. water bears can decrease their metabolism to less than 0.01 percent of normal or be entirely unnoticed and the water amount in their body may decrease to less than 1 percent. Water bears have been revived from the state of cryptobiosis for more than one hundred years and shown signs of life. Through it experiments it has been shown that frozen water bears could survive for ever. It is unknown what their limits may be but what is known is that they are the toughest animals alive for sure.