Scientists from the University of Georgia report in the current edition of the journal Evolution that different populations of North American monarch butterflies have evolved different sized wings depending on whether the population migrates to wintering grounds or is one of a number of nonmigratory monarch populations. Read the popular story at the BBC News Web site.
Average wing size averaged 20% smaller in nonmigratory populations, BBC reports.
“Comparing the largest to the smallest population, wings of monarchs from eastern North America are 20% larger than those from Puerto Rico. Averaging across all populations, migratory monarchs have wings that are 14% larger than non-migratory monarchs,” says Professor Sonia Altizer, whose lab conducted the research.
While scientists have known for some time that migratory butterflies typically have longer wings than nonmigratory species, this research appears to be the first time researchers have found wing size differences in populations of the same species that appear to be related to migration distance.
The Evolution article is available only by subscription or through library or institution site licenses.
The Altizer lab also works on a citizen science project tracking the spread of the protozoan parasite Ophryocystis in Project Monarch Health. The Monarch Health site also give a good overview of rearing monarchs.