In the seventeenth century, it was held by some that inside a human sperm there was a minute human being - a homunculus - that was planted inside the womb. Development consisted of the miniature homunculus enlarging and passing through birth and on to maturity-just like inflating a balloon.
Evolution, cell biology, biochemistry, and developmental biology have made extraordinary progress in the last hundred years - much of it since I was weaned on schoolboy biology in the 1930s. Most striking of all is the sudden eruption of molecular biology starting in the 1950s.
My prime interests are in evolution and development. I use the cellular slime molds as a tool to seek an understanding of those twin disciplines.
When, as an undergraduate, I began experiments on these slime molds in 1940, only one other person, Kenneth Raper, was working on them at that time. In fact, he discovered the model species Dictyostelium discoideum, which is the species used in the majority of the experimental work today.
