Switching heads

The entire process seems to have started in 1923, when a biologist named Walter Finkler reported that he had managed to successfully transplant the heads of insects. He’d been working with water boatmen, meal worms, and common butterflies – both in adult and grub form. The transplantation process was not complex. He’d grab two insects, cut off their heads with sharp scissors, and switch them. The fluid that the insects themselves leaked cemented the new heads in place. After a little time -- a 1923 article says a few weeks -- the insects were healed up and doing whatever their new heads told them to do. Finkler claimed that the heads of female insects on male bodies continued female behavior, and the head of one species of butterfly kept the habits of its own species, even when its body belonged to a different species.

-- from The Bizarre History of Insect Head Transplants