A bee visits a tree's flowers in a patch of forest near Panama's Soberania National Park. Photo by Antonio Castilla/University of Texas
Nov. 7 (UPI) -- Sex isn't just for animals. Plants mate too. But to produce seeds, they require the assistance of intermediary parties -- pollinators. New research suggests tiny bees are essential to this process.
Scientists at the University of Texas analyzed genetic markers from the pollinated flowers and seeds in a 2.5 square miles plot of Panamanian forest, revealing the foraging patterns of tiny bees. Their findings -- published this week in the journal PNAS -- showed small bee species helped trees as far as a mile apart reproduce.
There are hundreds of wild bee species, and many are quite small. Most studies focus on larger species, as they carry the heaviest pollen loads. But research shows small bees, some no larger than a grain of rice, visit more flowers and travel just as far as larger species.
"Size isn't everything," Shalene Jha, an associate professor of integrative biology at Texas, said in a news release. "These little bees are responsible for major beneficial impacts in terms of reproduction and gene flow."
Similar attempts to track pollinators across stretches of forest or field tend to hone in on just a few hundred square feet. The latest study was more ambitious.
"If you work in a small portion of forest, you're only capable of measuring pollen movement in a small area," Jha said. "We picked up the signal about how far these little bees move because we started doing work that was commensurate with the scale at which they're actually flying."
The research suggests smaller bees may play a key role in preventing inbreeding. By helping distant trees reproduce, pollinators ensure the next generation of trees are supplied with sufficient genetic diversity.
Researchers hope their work will inspire scientists to take a closer look at how different types of pollinators help plants reproduce in various ecosystems. If environmental threats continue to shrink the populations of larger bee species, smaller bees may have to take on more pollinating duties.
