Reading of the death of professor emeritus of ecology and evolutionary biology Henry Horn brought back fond memories. Horn’s class in Adaptive Patterns of Animal Behavior was enthralling, and taught me to use the scientific literature. A visit to his office was a unique experience. On the door were photos of his collaborators, with humorous names, but these turned out to be Horn in various stages of shaving off beard and trimming hair! Inside, he indicated a lamp that required insertion of pennies, a source of amusement, at least to him. There was also the crotch of a small tree, inverted, with the bark peeled off of all but the crotch triangle - evocative yet natural!

Before I set off to do senior-thesis field work on tree succession in the N.J. Pine Barrens, I sought guidance from Horn. He invited me to his home and led me on a walk in the adjacent woods, sharing insights on reading the history of forest patches and other natural history lore. He invited me to stay for pizza-from-scratch lunch he prepared for his kids. The most memorable moment was before our walk, when he opened a cabinet to get an increment corer (to sample tree rings), and it was chock-full of inverted tree crotches!

I reconnected with Horn when I returned to Princeton in 1987 for a postdoc. He showed me some of his works of art, shown under the name "J. Chester Farnsworth" (PAW, Sept. 24, 2001). My favorite was "Evolution of the Calculator" - abacus beads, pencil bits, and adding-machine parts deposited as "fossils" beneath the emergent machine.