User:SydneyPeskovitz/Nymph (biology)

Second Egg Hypothesis
In 1628, English physician William Harvey published An Anatomical Disquisition on the Motion of the Heart and Blood in Animals. In his writing, Harvey hypothesized that the pupal stage in insects was the result of imperfect eggs. While some eggs produced smaller versions of fully-matured insects known as nymphs, others created intermediate forms. Thus, these intermediate forms must go through a second egg stage to reach their adults form. This hypothesis attempts to explain the developmental differences between hemimetabolous and holometabolous metamorphosis. Though there is little evidence supporting Harvey's hypothesis, it is still significant to modern research in nymphs.