One day before a butterfly hatches the chrysalis changes it's look again. Its surface becomes transparent and you can see the fully formed butterfly sleeping inside.there is a state called "torpor" that is the insect's equivalent of sleep. An insect in torpor exhibits immobility and distinctly reduced response to stimuli, though it can rouse from torpor in a matter of seconds if the stimulus is strong enough.
The first thing that happens is that a lot of the caterpillars old body dies. It is attacked by the same sort of juices the caterpillar used in its earlier life to digest its food. It would not be far wrong to say the caterpillar digests itself from the inside out in a process called ‘histolysis'. Not all the tissue is destroyed. Some of the insect's old tissue passes on to its new self. The amount that does this varies between different insects. There is one particular sort of tissue left, in a number of places in the insects body are collections of special formative cells, which have played no part in the insects larval life, and have stayed hidden or protected during this partial death. Each of these groups of cells is called an ‘imaginal bud' or a ‘histoblast'. The job of these histoblasts is to supervise the building of a new body out of the soup that the insects digestive juices have made of the old larval body. This they do using the same biochemical processes that all insects use to turn their food into part of their bodies. This rebuilding process is called ‘histogenesis'. During this time the insect is very vulnerable because it cannot run away, and this is why insects try to choose somewhere safe to hide away when they are going through this incredible change.
No comments:
Post a Comment