Most of the small
animals like insects and arachnids (eg. Spiders, scorpions) have waterproof cuticles or
shell mainly composed of a substance called chitin, which is hard, strong and
impervious to many gases and liquids. It prevents them from drying up by the heat. The
different stages of the invertebrates have various ways to prevent drying up. The egg is surrounded
by a tough shell that is impervious to drought. It can last for months or even years,
waiting for the rain to come. The larval stage often develops underground to avoid the
heat. In the pupal stage, the cocoon or chrysalis protect the moth. The adult
invertebrates, as protected by the chitinous exoskeleton, may live a long and productive
life. It may lead a short life in the extreme, depending on the fat stored in its body.
The short life is long enough for it to mate and lay eggs. |
| Mysterious Journey Treasure Hunt |
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