The work by researchers at the School of Biological and Chemical Sciences looked at polyploid hybrids in the genus Nicotiana, the group that includes tobacco.
Unlike humans, which are diploids - with two copies of each of their 23 chromosomes (one from each parent), - polyploids can have three, four or more copies of each chromosome. This makes them particularly prone to producing hybrids and, - in contrast to better-known hybrids such as the mule which is (the sterile product of a cross between a male donkey and a female horse), means that crosses between polyploids are often fertile.
While hybrids might be expected to be a blend of the two parent species, the researchers found that they tended to have shorter and wider flower openings than both of the parent species which means that a wider range of pollinators can enter the flowers.
By allowing a wider range of insects to pollinate them, hybrids make themselves much less vulnerable to the extinction of a single pollinator.
Dr Elizabeth McCarthy, who carried out the work as part of her PhD at QMUL but who is now at University of California Riverside, said: "Some plants evolve increasingly specialised relationships with the species that pollinate them. A classic example is Darwin's Madagascan orchid, first discovered in 1798. Its exceptionally long nectar spur led Charles Darwin to propose that it was pollinated by a moth whose proboscis - the organ that extracts the nectar - was longer than that of any moth known at the time. Darwin's prediction was spectacularly verified 21 years after his death when just such a moth was discovered."
The problem with this sort of specialised relationship - which we now term coevolution - is that if one of the two species involved becomes extinct, the other is also doomed.
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The study, published in Nature Plants, was produced in collaboration with the Royal Botanic Gardens, Kew, the Natural History Museum in London and the University of California, Riverside.