Love in the time of the Cretaceous (Picture: YouTube)

It’s a question 240million years in the making, but a dinosaur expert says he has finally worked out how the terrible lizards had sex.

With many dinosaurs armed to the teeth with spiky tails and reinforced plating, the normal method of mating in the animal kingdom – mounting from behind – sounds not so much impractical as deadly.

Brian Switek, whose book My Beloved Brontosaurus is out in May, told the Sunday Times: ‘The females could not raise their tails because the bones at the top end were fused.

‘And some species had lethal spikes on their backs that would have been impossible to get past.’




Computerised recreations of how Kentrosaurus couples mated produced by Berlin’s Museum of Natural History concluded that the male dinosaurs faced castration if they mounted from behind.

Tyrannosaurus Rex: Rawr (Picture: File)

‘These prickly dinosaurs must have had sex another way,’ said the museum’s Heinrich Mallison.

‘Perhaps the female lay down on her side and the male reared up to rest his torso over her. Other species would have used different positions, like backing up to each other.’

However, Professor John Long of South Australia’s Flinders University scorned the idea that dinosaurs including Tyrannosaurus Rex could have mated in a missionary-style position.

‘A 33ft-long ankylosaurus, with spikes and armour, would have had a 6ft 6in penis to bridge the gap when close to a female,’ he said.

Professor Switek said the argument would go on until the search for the paleontological Holy Grail ended.

‘Soft tissues are seldom preserved during fossilisation, so we have never found a fossilised phallus, but doing so would solve many mysteries,’ he said.