Plant diversity down to birds and bees
Interactions with pollinators, such as birds and bees, are thought to be a driving force in the diversification of flowering plants.
Researchers at The University of Queensland (UQ) and The Australian National University investigated how interactions between Australian plants and their bird or bee pollinators have shaped the number of flowering plants we have today.
The study, led by UQ’s Dr Alicia Toon from UQ’s School of Biological Sciences, found that there was less diversity of species in pea lineages pollinated by birds.
“We found that the ancestors of today's peas were pollinated by bees, and most still are,” said Dr Toon.
“Pollination by birds only came about later, and happened about 11 times.
“Peas pollinated by bees diversify more than those pollinated by birds – for each pea which switched to using a bird for pollination, there are fewer of its descendants today than there are for its cousins that kept using bees.
“This is likely due to birds being able to fly further and revisit different populations of pea plants, constantly mixing genes between these populations and reducing speciation.”
Speciation, the evolution of a new species, can occur when a population is geographically isolated from other populations of the same species.
If the isolated population is unable to exchange genes with other populations, it may take a different evolutionary path and become a new and genetically distinct species.
“Bees don't fly as far as birds, so pea populations pollinated by bees might be more isolated from one another and, over time, this can lead to them becoming different species,” said Dr Toon.
“Our research highlights how different plant-pollinator interactions may have contributed to the diversity of flowering plants.”
The research is part of an ongoing collaboration between the Cook lab at UQ and the Crisp lab at The Australian National University into the evolution of Australian plants and insects. The study was published in BMC Evolutionary Biology on 7 March 2014.
Contact: Dr Alicia Toon, 0411 954 179 or email@example.com