Having unexpectedly become a eunuch, Richard Wassersug, a professor in the department of anatomy and neurobiology at Dalhousie University in Halifax, Nova Scotia, did not despair. Being curious, he turned his apparent tragedy into a happy new obsession. Along with his ongoing exploration of amphibian biology (described last week), Wassersug now conducts research about eunuchs.

In 1998, at the age of 52, Wassersug was diagnosed with prostate cancer. His website explains the situation he then faced - a situation not so very unusual, but one seldom discussed in public: "When first-line curative therapies for prostate cancer fail, patients are offered either surgical or chemical castration. Strictly speaking, the patients who accept this treatment are 'neutered'."

Wassersug discovered that being a eunuch has, in addition to the famous drawbacks, some unexpected benefits: less tendency to be aggressive and pugnacious; more and maybe deeper empathy with other people; and without the hormone-driven sexual distraction, a relaxed comfort in savouring the beauty in women's faces.

Science mostly overlooks eunuchs as a subject of interest and as a likely source of valuable insights. Wassersug set out to correct that.

The Wassersug eunuch studies, many done in collaboration with other scientists, include appraisals of medico-social dilemmas. There are also some wonder-filled looks at unfamiliar parts of the human condition.

Some are medically oriented, others are more social-focused. The Sexuality and Social Performance of Androgen-Deprived (Castrated) Men Throughout History: Implications for Modern Day Cancer Patients is surprisingly upbeat. It says: "The historical accounts suggest that, given the right cultural setting and individual motivation, androgen deprivation may actually enhance rather than hinder both social and sexual performance. We conclude that eunuch history contradicts the presumption that androgen deprivation necessarily leads to social and sexual impotence."

Wassersug's research also took him down side paths where academics truly seldom tread, and where he saw fewer happy prospects.

There are men who, for reasons unrelated to illness or injury, want to be castrated. Wassersug wants to understand why. In a study called A Passion for Castration: Characterising Men Who Are Fascinated With Castration, But Have Not Been Castrated, Wassersug and colleagues "identify factors that distinguish those who merely fantasise about being castrated from those who are at the greatest risk of genital mutilation."

Some of the men do more than fantasise. The study Eunuchs in Contemporary Society: Expectations, Consequences and Adjustments to Castration tells their story. And it reports what may be the most disturbing fact about the voluntary castrati: "The majority of the castrations (53%) were not performed by medical professionals."

· Marc Abrahams is editor of the bimonthly Annals of Improbable Research and organiser of the Ig Nobel prize