Evolution Blossoms
Genes Sequencing Flower Petal Colors Scrutinized
He may not be sailing aboard the HMS Beagle, but UCSB Professor Scott Hodgesmay provide the scientific community with new evidence that can help identify evolutionary progress of on a genetic level through his work on columbine flowers.
Although the study of genes began in 1856 after Gregor Mendel’s work with pea plants, there are still many genes whose functions are unknown to the scientific community. Hodges explained that columbine flowers have a variety of petal colors – such as red, yellow, and white – in order to attract certain pollinators such as hummingbirds and hawkmoths.
In their work together, Hodges and his associate Nathan Derieg found that columbines with red petals were naturally pollinated by hummingbirds and those with white or yellow petals were pollinated by hawkmoths. When these flowers shift from being predominantly pollinated by hummingbirds to hawkmoths, the genes for the red petals adjust through the process of natural selection, a key component in the theory of evolution. “We think – as far as plants are concerned – there are some more efficient ways for plants to eliminate these genes, so by finding this out we can identify its evolutionary path,” Hodges explained.
The pair of researchers was also able to identify 34 of the approximately 25,000 candidate genes that might be responsible for petal colors among the columbine flower by sequencing the entire columbine genome and comparing it to databases from other plant species. Genetic sequencing is a tedious process that requires individuals to “decode” the order of DNA nucleotides in a genome in order to better understand its function-how genes work together to direct the growth, development, and maintenance of an entire organism.
By mapping out gene functions among the columbine flower, Hodges and his team are part of a larger multi-university study in the process of sequencing the entire columbine genome. Ultimately, he may provide scientists with new information about plant genes that can help manipulate plants to be more drought-resistant.
