May 06, 2013
Owen McMillan longs to explain the evolution of Nature’s beautiful diversity. Pulling aside a mesh curtain, he steps inside the enclosure and cups his hand over a butterfly
Owen McMillan longs to explain the evolution of Nature’s beautiful diversity. Pulling aside a mesh curtain, he steps inside the enclosure and cups his hand over a butterfly, pinching its bright wings between thumb and forefinger. Tiny knifelike rays of a Chinese-red sunburst advertise its toxicity to predators. Bright yellow pollen grains pepper its spiraled tongue.
“Heliconius eat pollen,” explains Owen, “which allows them to live for a long time.” This butterfly’s long lifespan gives the flowers time to train them to visit. “We’ve discovered that to get consistent results and to have enough butterflies for our genetic work, we need to focus on the plants.”
Carefully tended by Peruvian research assistant Moises Abanto, hotlips flowers offer their pollen and 25 species of passion vines provide female butterflies a place to lay their eggs, and food for enough larvae to supply several research labs. The Heliconius Genome consortium took shape here. Last year they broke the code, sequencing the entire genome of Heliconius melpomene. By comparing important sequences in species that mimic each other’s patterns, researchers found that hybrids exchange genes controlling pattern and color.