For the first time ever, a team led by the University of Colorado Boulder has sequenced the internal bacterial makeup of the three major life stages of a butterfly species, a project that showed some surprising events occur during metamorphosis.
The team, led by CU-Boulder doctoral student Tobin Hammer, used powerful DNA sequencing methods to characterize bacterial communities inhabiting caterpillars, pupae and adults of Heliconius erato, commonly known as the red postman butterfly. The red postman is an abundant tropical butterfly found in Central and South America.
The results showed the internal bacterial diversity of the red postman was halved when it morphed from the caterpillar to the chrysalis, or pupal stage, then doubled after the pupae turned into active adult butterflies. The study is important because communities of bacteria inhabiting other insects have been shown to affect host nutrition, digestion, detoxification and defense from predators, parasites and pathogens, said Hammer of the ecology and evolutionary biology department.
"What we saw was that the microbial community simplified and reorganized itself during the transition from caterpillar to pupa," he said. "Then we saw the diversity double after the adult butterflies had emerged and began going about their business of feeding. That was a little surprising to us."
A paper on the subject was published online Jan. 23 in the journal PLOS ONE. Study co-authors on the paper included CU-Boulder Associate Professor Noah Fierer of the ecology and environmental biology department and W. Owen McMillan of the Smithsonian Tropical Research Institute in Panama City, Panama. The butterflies were collected at a field site in Gamboa, Panama, and data analysis was done at CU-Boulder.
The collection of microorganisms on a single animal, collectively known as the microbiome, has become important because such bacterial groups have been found to a
|Contact: Tobin Hammer|
University of Colorado at Boulder