Jan Swammerdam
He got evidence from his dissections. By examining larvae, he identified adult features in pre-adult animals. For example, he noticed that the wings of dragonflies and mayflies exist before their final molt. Swammerdam used these observations in his 1669 publication, Historia Insectorum Generalis (The Natural History of Insects).  This work included many descriptions of insect anatomy. It was here that Swammerdam revealed that the "king" bee has ovaries. Biblia natura published posthumously in 1737, carried the first confirmation that the queen bee is the sole mother of the colony. Despite five intense years of beekeeping, the mode of honey bee reproduction escaped him as he wrote, "I do not believe the male bees actually copulate with the females."