Professor of Evolutionary Biology at ANU Michael Jennions with the latest study find that there is no optimum size when it comes to penis size.

Professor of Evolutionary Biology at ANU Michael Jennions with the latest study which finds there is no optimum size when it comes to penis length. Photo: Jay Cronan

The perhaps unrealistically high expectations Canberra women have of penis size seems to have captured the world's attention.

Australian National University reproductive biologist Professor Michael Jennions and his PhD student Dr Brian Mautz were in demand on Tuesday by the international media keen to report on their definitive research into whether penis size was important to women and just how big did they want it to be?

Meanwhile, the view counter on a YouTube video in which Professor Jennions describes the study's methodology and findings crashed at about 9am on Tuesday after 300 hits.

The study, published in the American journal Proceedings of the National Academy of Sciences (PNAS for short) was followed up by CNN, Time magazine, National Geographic, Nature, Science, The Huffington Post, The Boston Globe and even The Economist.

Professor Jennions had expected the story to prick media attention, but he was quite overwhelmed by a day filled with media interviews.

''We expected media interest, but it has been far greater than we expected - basically, a who's who of established news magazines and media sources have contacted us.''

This is a far cry from the usual media attention given Professor Jennion's investigations of the sex lives of crickets, frogs and fiddler crabs.

Deciding to fill the void of scientific research into the importance of penis size in the human mating process, Professor Jennions and Dr Mautz discovered penis size was just as important as height in boosting a man's sexual attractiveness to women and that women showed a clear preference for penises in excess of 13 centimetres in their flaccid state.

This is larger than 95 per cent of Italian men used in the body measurement sample on which the Australian study was based.

Professor Jennions would not be drawn into a debate about whether the 105 mainly Canberra women who took part in the survey and voted for much larger penises than those attached to 95 per cent of the population were being too ''harsh''.

Women had long been subjected to research and scrutiny into their bodies and sexual attractiveness to men, he noted.

Feedback on Twitter suggested public interest in expanding the study to encompass other populations, ethnicities, and to include other traits.

Dr Mautz, who fielded the North American media from his base at the University of Ottawa, said: ''Reaction to the article has been surprisingly good. I didn't expect the study to get this big. I think the amount of coverage certainly shows that people are interested in knowing exactly what is going on with penis size.''

Professor Jennions said one of the interesting aspects of the day's interviews had been that male and female interviewers seem to vary in their comfort dealing with the issue, and in the ease with which they said the word ''penis''.

''Women tend to laugh more. Men sound more nervous,'' he reported.

He left the final word on the topic to his mother, who emailed him on Tuesday saying, ''I don't see any women who would disagree with your results. Good job that love enters [into it] too, but that doesn't change the ideal.''