I was an undergraduate when I first saw a film of Dictyostelium aggregating, and decided that it was something I had to study. It would be great to say, 30-odd years later, that I had a clear vision of great issues in biology that could be addressed with such an organism, but actually I just thought it was neat. I suppose it had the correct combination of interest and mystery. Like hundreds, if not thousands of people before and since, I was fascinated by its regularity, its rhythms, and for someone schooled in bacteriophage, it seemed simple. If you are blessed with youth and think Dictyostelium development is simple, I hope this book will help you to realize your error without discouraging you.

The thousands who have been taken by this strange little organism include better minds than ours. John Tyler Bonner tells of being a young assistant professor at Princeton who one day received a call to show his slime mold films to Albert Einstein. John showed up with his 16 mm projector and he thinks Einstein and his colleagues were suitably impressed, but he does not actually know. John speaks wonderful French, but Einstein conversed in German.

When I first started to work on this organism, with Maurice and Raquel Sussman at Brandeis University, it was thought remarkable that a eukaryotic organism induced genes and enzymes, just like E. coli induced the gene for β-galactosidase.