On evolution and art: questions of sex and aesthetics

"Pinker is right about value and status, but he thinks all art is – I don't think it would justify the cost. Miller's right – he's a bit heavy-handed about it. But it's fun," Walsh says.

"And I don't have much truck with Boyd's theory – but that's mainly because I don't understand it. I don't know that it's an adaptive theory … it's art academic – and he's the only one that isn't a scientist so that it turned out that way, in hindsight, doesn't surprise me."

Changizi, he says, offers some profound insights.

"They may sit on top of Miller or Pinker, but I'd say there's no doubt that some of his insights are very relevant of why people make music… it's an art that requires a resource."

And Walsh's theory?

"My background is science … for me, it's obvious that art serves a biological function – whatever that function might be – because it absorbs so many resources that there must be a pay-off," he says. "The question is only what is that pay-off? Everything else, as far as I'm concerned, is bleeding obvious."

Walsh "applied pressure" to his curators to draw from his own extraordinary collection for the exhibition, which features 230 works and objects, but 58 are on loan from galleries and museums around the world, and there are nine new commissions created specifically.

He approached British artist Mat Collishaw to create a new work for Geoffrey Miller's exhibition within the exhibition; Miller's room at MONA is arguably the most provocative and, arguably, accessible: his theory being that we make basically to get laid. (Pity the security guard who has to spend a shift in front of the giant Jeff Koons photograph of him performing a sex act on then-wife, porn star Ilona "Cicciolina" Staller, Takashi Murakami's huge ejaculating sculpture The Lonesome Cowboy, and an entire wall of erotic Japanese woodcuts.)

"There's no doubt Miller's a bit of a pervert, and I think he chose those works because he likes them," Walsh says. "But they are somewhat more relevant to his argument than any of the other works are to anyone else's argument. At least he's honest!"

For Collishaw, one of the YBAs, (Young British Artists, the term coined for the hot young artists in the 1990s), and best known for his work Bullet Hole, a giant enlarged photograph of a bullet hole in a human head (now owned by Walsh), the chance to create a new piece for MONA was irresistible.

"Everyone knows David Walsh; I've got galleries in New York where they know him, and Naples," he says. "He has a very international reputation."

Collishaw was also drawn to the show's concept of curation.

"With art curators, it's a bit like the church; they're the scribes and they can come between the art and the people and tell us what to think and how to interpret it," he says.

"You get the message that it's all subjective and anybody can take their own thing out of it. I think good art – and this is not a shocking revelation – should be open to interpretation. Geoffrey Miller's using these works to illustrate his theories and looking at art in a different way through the themes of evolutionary psychology, our motivations that we're not really in control of."

As well as the confronting Bullet Hole, Collishaw's other works have all tended towards the grotesque – there's the resin-sculpted flower riddled with syphilitic disease, his portrait series of death row inmates' final meals, extreme close-ups of squashed butterflies and his photo series staging scenes of Nazi couples post-suicide in their bunkers – but for this show, he has created something that at first glance looks purely beautiful.

Centrifugal Soul, an extraordinarily detailed zoetrope sculpture plays into Miller's theory that the human tendency for making art stems from the natural instincts of reproduction.

"His theory is that we do a little dance, sing a song, tell a story – whatever it takes, just to indicate to the women that we have what it takes! We can build a fire, a shelter, but women were like, 'what else have you got?' " Collishaw says.

Centrifugal Soul features dozens of tiny sculpted birds of paradise performing elaborate mating dances while flowers burst into bloom.

"It was kind of fortuitous that all the birds are native to Australia and Papua New Guinea – I wanted to make a work about the origin of this theory of Geoffrey's and they're very visual examples. Other than the peacock, this is the area where birds have courtship rituals like no other species on earth."

It's certainly lacking the grotesque motifs he's mostly known for.

"People who saw it in London, while it was being made, said to me, 'where's the bad stuff?' There is one small thing. If you look very closely, there's one bowerbird right at the bottom who steals a bottle lid from another bird."

Not quite a syphilitic flower, then?

"No – but I would hope that the work is kind of a little bit chilling anyway – this thought that we're programmed to make art because it's going to get us laid, is quite a disturbing thing. That our genes are instructing us to behave a certain way; that's kind of spooky," Collishaw says.

And as for Miller's theory – does Collishaw make art to get laid?

"Well … I think most artists do have quite big egos," he says. "But I was always quite shy, and it was almost a way of communicating. To make an art work that could speak for me, was a way of sharing feelings with people without really doing it. If you can't articulate yourself very well through conversation, then making an art work is another way of getting attention. And maybe get laid on the side."

On the Origin of Art is at MONA until April 17.

Kylie Northover travelled to Hobart as a guest of MONA.