Is that me or my twin?

Can twins recognise themselves in photos? What are the neural bases for being disgusted by cheese? Are cats a liquid or solid? Research questions such as these can only mean one thing; this year's IgNobel Prize winners have been announced.

The IgNobel prize is awarded to academics from across the science disciplines for papers that first make us laugh, then make us think. During the ceremony winners are presented with a 10 trillion-dollar bill (from Zimbabwe) by actual Nobel Laureates and given 60 seconds to make a speech which, if overlong, is interrupted by an eight-year-old girl repeating 'Please stop. I'm bored' until they finish.

This was the 27^th 'first annual' IgNobel Prize Ceremony which saw the premiere of The Incompetence Opera, a mini-opera that presents a musical encounter with the Peter Principle and the Dunning-Kruger Effect, about how and why incompetent people rise to the top — and what that implies for everybody.

Marc Abrahams, master of ceremonies, and Editor of the magazine Annals of Improbable Research which started the event, closed the ceremony with the traditional: 'If you didn't win an Ig Nobel Prize tonight – and especially if you did – better luck next year.'

Researchers in the UK and France won the medicine prize for their attempts to measure the extent to which some people are disgusted by cheese – which a surprising amount of people are. Jean-Pierre Royet, David Meunier, Nicolas Torquet, Anne-Marie Mouly and Tao Jiang found in their fMRI study that the internal and external globus pallidus and the substantia nigra are more activated in participants who are anti-cheese.

The winner in the cognition category was a study with the title Is That Me or My Twin? Lack of Self-Face Recognition Advantage in Identical Twins. Psychologists Matteo Martini, Ilaria Bufalari, Maria Antonietta Stazi and Salvatore Maria Aglioti explored the difficulty twins have in recognising themselves. They concluded that 'to distinguish the self from the co-twin, monozygotic twins have to rely much more than control participants on the multisensory integration processes upon which the sense of bodily self is based. Moreover, in keeping with the notion that attachment style influences perception of self and significant others, we propose that the observed self/co-twin confusion may depend upon insecure attachment.'

This year's winner in the physics category was a letter by Marc-Antoine Fardin (Laboratoire de Physique, École Normale Supérieure de Lyon) which used fluid dynamics to ask whether cats could be both a solid and liquid, thanks to their uncanny ability to fit to the shape of most containers. Part of his acknowledgements read: 'I thank L. and J.F. Berret for providing a reliable technique to load Felis catus in different geometries: 1. Bring an empty box; 2. Wait.'

Milo Puhan, Alex Suarez, Christian Lo Cascio, Alfred Zahn, Markus Heitz, and Otto Braendli, won this year's peace prize for demonstrating that regular playing of a didgeridoo is an effective treatment for obstructive sleep apnoea and snoring. The economics prize-winners Matthew Rockloff and Nancy Greer (Central Queensland University) explored whether contact with a live crocodile affects a person's willingness to gamble (it does!).

James Heathcote from the UK asked a nagging question, why do old men have big ears? His paper, published in the British Medical Journal, won the anatomy prize. In the biology category winners Kazunori Yoshizawa, Rodrigo Ferreira, Yoshitaka Kamimura, and Charles Lienhard, discovered a female penis and male vagina in a cave insect.

Finally researchers in Spain won the obstetrics prize for finding that a developing human foetus responds more strongly to music that is played electromechanically inside the mother's vagina than to music that is played electromechanically on the mother's belly. Marisa López-Teijón, Álex García-Faura, Alberto Prats-Galino, and Luis Pallarés Aniorte, also developed a product based on this research – the Babypod.

See a full list of winners and links to their papers. A recording of the ceremony is also available. You can also find more 'improbable research' in our archive.