Rather than dying out in the dimly lit aftermath of a ginormous asteroid impact, dinosaurs on Earth may have instead spread to other planets and built a terrifying space-conquering empire.
Organic chemistry expert Prof Ronald Breslow has suggested from new research into DNA that the Jurassic Park monsters may in fact be living in highly evolved civilisations on other worlds - quite possibly with their own interstellar exploration programmes.
"We would be better off not meeting them,” the Columbia University boffin warned, however.
The alien dino theory in Breslow's paper published today in The Journal of the American Chemical Society is just one speculative conclusion of his research into DNA shapes. In his research the award-winning academic probed a mystery that's bothered boffins since the last century: why amino acids and sugars on Earth are always structured in a particular way.
He analysed the structure of proteins, sugars and genetic materials in DNA and RNA to find out why our planet's building blocks of life mainly exist in a specific orientation. The scientist pondered:
There are two possible orientations, left and right, which mirror each other in the same way as hands. This is known as "chirality". In order for life to arise, proteins, for instance, must contain only one chiral form of amino acids, left or right. With the exception of a few bacteria, amino acids in all life on Earth have the left-handed orientation. Most sugars have a right-handed orientation. How did that so-called homochirality, the predominance of one chiral form, happen?
Breslow laid out evidence that unusual amino acids were brought to Earth by a meteorite four billion years ago and kickstarted life on our planet. He examined whether these putative space rock amino acids set the pattern for the L-shaped amino acids that make up most life on Earth and investigated whether those could lead to D-sugars of the kind present in DNA.
He cites evidence that L-shaped amino acids were found on a meteorite that landed in the 1960s. Life built out of the same basic building blocks could, on other worlds, take similar forms to creatures that roamed pre-historic Earth, as Breslow noted:
Such life forms could well be advanced versions of dinosaurs, if mammals did not have the good fortune to have the dinosaurs wiped out by an asteroidal collision, as on Earth. We would be better off not meeting them.
On the question of just why other planets may be inhabited by our dinosaurs, a second paper published last week in the Cornell Earth and Planetary Astrophysics Journal suggests the trillion-ton meteorite impact that killed the dinosaurs 65 million years ago may have blasted off small bits of dinosaur DNA out into space. And quite a lot of those bits of dino-carrying rock will have landed on amenable planets, say the paper's authors.
The Cornell boffins have worked out what quantities of Earth matter would have been kicked out by the force of the impact and where that matter landed. They estimate that bits of Earth matter will have headed into the red dwarf Gliese 581 system some 20 light years away, which is thought to have a super-Earth orbiting at the edge of its habitable zone.
And of course if life from Earth was spewed into space by meteorites, then of course the life which arrived on our homeworld via meteorites must have come from somewhere else - somewhere perhaps filled with super-dinosaurs with iPads, satellite telly and Star Wars-style Death Stars.
Evidence for the Likely Origin of Homochirality in Amino Acids, Sugars, and Nucleosides on Prebiotic Earth was published in The Journal of the American Chemical Society. Transfer of Life-Bearing Meteorites from Earth to Other Planets was published in Cornell's Journal of Earth and Planetary Physics. ®