Eleanor Maguire was in an apprehensive mood. She had just flown into Boston, Massachusetts, to collect an Ig Nobel Prize in Medicine at Harvard University. But just before the ceremony, she was having second thoughts. “What have I gotten myself into?” she asked herself aloud.

Earlier this year, Maguire, a neuroscientist at University College London, had barely heard of the Ig Nobels, which were awarded for the 13th time on 2 October by a self-appointed panel for “research that cannot or should not be reproduced”. Maguire had no idea why she'd won — although the title of a paper she co-authored in 2000, “Navigation-related structural change in the hippocampi of taxi drivers” (Proc. Natl Acad. Sci. USA 97, 4398–4403), might have offered her a clue.

In the paper, Maguire and her colleagues showed that the posterior hippocampus, thought to be a navigation centre in the brain, is enlarged in London taxi-drivers. What's more, the volume of the hippocampus correlates with years of experience in the cab. This research was no joke, as it suggested a capacity for structural plastic changes in healthy human brains — a finding with important clinical implications. Yet it plunged Maguire into an annual prize-giving ceremony best-known for its frivolity and sophomoric gags.

This year, one lucky spectator won a date with a proper Nobel laureate, Richard Roberts (Physiology or Medicine, 1993), also known as Mr December in the 1997 “Studmuffins of Science” calendar. Another got to meet Stephen Wolfram, who promised to explain his intense 1,200-page tome A New Kind of Science over a cup of tea.

In a “24/7 nanolecture”, geneticist Eric Lander summarized the Human Genome Project in 24 seconds — “The genome cost US$3 billion and gave us three billion letters: one dollar a letter. Such a deal!”— and then, rather more successfully, in seven words: “Genome. Bought the book. Hard to read.”

The physics Ig Nobel went to Australian investigators for “An analysis of the forces required to drag sheep over various surfaces” (Appl. Ergon. 33, 523–531; 2002). Yukio Hirose of Kanazawa University in Japan captured the chemistry award for his studies of a bronze statue that failed to attract pigeons.

Researchers at Stockholm University, Sweden, claimed the interdisciplinary prize for “Chickens prefer beautiful humans” (Hum. Nature 13, 383–389; 2002). And C. W. Moeliker of the Natuurmuseum in Rotterdam, the Netherlands, won the biology prize for documenting the first known case of homosexual necrophilia in the mallard duck (Deinsea 8, 243–247; 2001).

In her acceptance speech, Maguire told the crowd that she got a 50% discount on a cab fare “for showing that taxi-cab drivers are special” — perhaps the first instance of anyone benefiting materially from winning an Ig. At the ceremony's end, she said: “Some of the other winners did amazing things with sheep, pigeons, chickens and mallard ducks. But for now I'll stick with taxi-drivers.”