Nobody knew why Ian Hamilton was called Buttercup but the name was so irresistible that it stuck. He was about 40, I would imagine, although children are notoriously bad at gauging the ages of adults, and was my private school's zoology teacher.
Buttercup was married but had no children. I think the war had put a stop to his ambitions. He had been at the University of Cambridge and wanted to do research. I remember going to his house a couple of times and it was very austere.
I was a quiet boy, whose first day at boarding school had been the most miserable of my life. In fact, I did not lack confidence, but I was an only child who had grown up in the Depression years of the 1930s, and my preoccupation with the world of animals meant I loathed the idea of being sent away to school. I had also watched my father slowly dying from war wounds. He finally passed away when I was 14.
But I had always loved animals - I had enclosures for tame foxes in the garden of my home and had the childhood fantasy that I could train them to hunt foxhounds - and Buttercup, who even signed his letters with this unusual nickname, was passionate about zoology. In his own, highly unorthodox fashion, he was a minor genius.
He had an open disdain for the examination syllabus and demanded that we sixth-formers go far beyond it. When he found responsive students, he was inspirational and treated us as if we were university scientists. But if you didn't like his subject, he was horrible. There was nothing fair or impartial about Buttercup, and that was part of his charm.
His first principle was that it is impossible to teach zoology. All he could do, he said, was to teach us to learn. Teaching answers, he believed, clogged up the brain with undigested facts. I was fascinated by this approach and worked harder to please him than I had ever done for anyone else.
I had joined the school's natural history society and Buttercup encouraged me to write for its magazine after he learned that I had a garden collection of some 100 toads. My first published article, "Toad in the hole", won a prize of five shillings.
Buttercup was relentless in how he developed our enquiring minds. He even sent me odd packages in the holidays. On one occasion, a package of molluscs arrived, with a note telling me I was to dissect them, extract the radula, and tell him how it worked. (I remember having to throw away one such package because it was stinking so badly; he really couldn't understand why I hadn't opened it and worked on the project.)
Buttercup also had a passion for Lewis Carroll and created his own version of the Alice story - Alice Under the Microscope - which he illustrated himself. There was Alice, on a microscope plate, being studied before she was sucked into the microscope for her travels. Years later, when I was at the University of Birmingham, I recreated this scenario in a carnival float, with an Alice, a giant microscope and an enormous giraffe.
The other teacher who was terribly important to me was Bill Coulson, or Beetle, as we called him, who taught botany - I always thought the nicknames of these two teachers should have been reversed. Aside from botany, Beetle was very excited about the modern poets WH Auden and Christopher Isherwood. I couldn't believe how people like this, and Dylan Thomas, could play so wonderfully with words. That helped me to refine my own use of words later in my studies of animals.
So many academics write in such an ugly, clumsy way but Beetle taught me the importance of clear communication. I have tried to be eloquent with scientific writing, to get myself across to a wide audience, something that is so important.
Much later, as I kept in touch with Buttercup, I learned the origin of his own odd name. His first lesson as a teacher had started with the question "Why do no buttercups grow in the middle of the road?" By the time the ecological significance of his question had been conveyed, he had been dubbed with a nickname that would stick for ever.
Desmond Morris was talking to Jo Knowsley.
Born: 24 January 1928, Purton, Wiltshire, England
Education: Miss Denner's primary school, Swindon; Swindon High School; Dauntsey's School, West Lavington, Wiltshire; University of Birmingham; University of Oxford
Career: Zoologist, author, broadcaster.