The animal world is full of beautiful and mysterious processes, for example, the metamorphosis of caterpillars into butterflies. Amazing processes take place inside the cocoon: a genetic program is launched, according to which all the tissues of the caterpillar larva, with the exception of the circulatory and nervous systems, are destroyed, and new organs are formed from imaginal disks (clusters of cells, peculiar embryos of future butterfly organs). The formed butterfly flies out of the cocoon to live only from a few hours to several months, during which it should have time to produce offspring.