Long-winged Monarchs

I just read results of a University of Georgia study of migratory and non-migratory Monarch butterflies.  The nonmigratory animals from Hawaii, Costa Rica, South Florida and Puerto Rico have smaller bodies and wings.  Their studies support the findings in migratory birds that the best shape for long-distance flight involves long wings with a narrow tip to help reduce drag.  The eastern migratory butterflies also have larger bodies, presumably storing more fat as fuel for the trip.
There is evidence that the migration of Monarchs to Mexico may be threatened in the long run.  In addition to storms which can threaten their winter haven, there has been a 30 year decline in the population of migrating females.  While the overall population appears stable, the loss of migrating Monarchs could threaten the long winged variants.
This article is at Freshare.net, a site suggested to me by George Deatz of Friends of the Garden.  Freshare.net is "A community of people who enjoy the Ozarks outdoors".  It is based in Arkansas and published by Robert Korpella, a freelancer writer.  I think you will find other posting of interest and I have added their link to our blog.