The document discusses the life cycle of the monarch butterfly. It begins as an egg laid on milkweed leaves by the female monarch. The eggs hatch into larvae that eat milkweed leaves for two weeks until transforming into caterpillars. The caterpillars then form pupas and undergo transformation over two weeks into adult monarch butterflies. The butterflies migrate south for winter and return north in spring, following consistent migration patterns each year during which huge numbers gather together.