ATHENS, Ga., Feb. 11 (UPI) — U.S. scientists say they’ve determined monarch butterflies that migrate long distances have evolved larger and more elongated wings than other butterflies.
The University of Georgia study examined the size and shape of monarchs from migratory and non-migratory populations using sophisticated and precise computer imaging. Associate Professor Sonia Altizer and doctoral student Andy Davis compared migratory monarchs from the eastern and western United States to those in Hawaii, Costa Rica, South Florida and Puerto Rico that do not migrate.
They said their findings in monarchs were consistent with previous studies comparing migratory and non-migratory bird species, which indicate the best shape for long-distance flight involves long wings with a narrow tip to help reduce drag.
The team said it found monarchs from the migratory populations differed in body size, suggesting each population could have adapted in subtly different ways to the demands of migration.
The study was published in the online edition of the journal Evolution.
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