RESUMEN
The field of plastic surgery, formally organized in 1931 with the founding of the American Society of Plastic and Reconstructive Surgery, was shaped in many ways by a small practice of Philadelphia physicians. At the center of the practice was Warren B. Davis, a Philadelphia otolaryngologist and plastics pioneer whose innovations in cleft palate surgery would lead to significant improvements in functional and cosmetic outcomes in his time. In addition to his own innovations, Davis was responsible for the training of John Reese, the inventor of the Reese dermatome that changed the face of burn medicine during World War II. Aside from his contributions to surgery and the founding of the American Society of Plastic and Reconstructive Surgery, Dr. Davis was also the founder and first editor of the Plastic and Reconstructive Surgery journal which to this day is the premiere, authoritative journal of plastic surgery. Lastly, Dr. Davis established a plastic surgical practice, now Jefferson Plastic Surgery. Unique in its longevity, this practice would continue to shape the field of plastic surgery and continues to improve lives today-109 years after its founding in 1913.
RESUMEN
Migratory divides are contact zones between breeding populations that use divergent migratory routes and have been described in a variety of species. These divides are of major importance to evolution, ecology and conservation but have been identified using limited band recovery data and/or indirect methods. Data from band recoveries and mitochondrial haplotypes suggested that inland and coastal Swainson's thrushes (Catharus ustulatus) form a migratory divide in western North America. We attached light-level geolocators to birds at the edges of this contact zone to provide, to our knowledge, the first direct test of a putative divide using data from individual birds over the entire annual cycle. Coastal thrushes migrated along the west coast to Mexico, Guatemala and Honduras. Some of these birds used multiple wintering sites. Inland thrushes migrated across the Rocky Mountains, through central North America to Columbia and Venezuela. These birds migrated longer distances than coastal birds and performed a loop migration, navigating over the Gulf of Mexico in autumn and around this barrier in spring. These findings support the suggestion that divergent migratory behaviour could contribute to reproductive isolation between migrants, advance our understanding of their non-breeding ecology, and are integral to development of detailed conservation strategies for this group.
Asunto(s)
Migración Animal , Aislamiento Reproductivo , Pájaros Cantores/fisiología , Animales , Canadá , América Central , Sistemas de Información Geográfica , Geografía , Haplotipos , México , Estaciones del Año , Estados UnidosRESUMEN
Each autumn billions of songbirds migrate between the temperate zone and tropics, but little is known about how events on the breeding grounds affect migration to the tropics. Here, we use light level geolocators to track the autumn migration of wood thrushes Hylocichla mustelina and test for the first time if late moult and poor physiological condition prior to migration delays arrival on the winter territory. Late nesting thrushes postponed feather moult, and birds with less advanced moult in August were significantly farther north on 10 October while en route to the tropics. Individuals in relatively poor energetic condition in August (high ß-Hydroxybutyrate, low triglyceride, narrow feather growth bars) passed into the tropics significantly later in October. However, late moult and poor pre-migratory condition did not result in late arrival on the winter territory because stopover duration was highly variable late in migration. Although carry-over effects from the winter territory to spring migration may be strong in migratory songbirds, our study suggests that high reproductive effort late in the season does not impose time constraints that delay winter territory acquisition.
Asunto(s)
Migración Animal/fisiología , Constitución Corporal/fisiología , Muda/fisiología , Pájaros Cantores/fisiología , Ácido 3-Hidroxibutírico/sangre , Animales , América Central , Pennsylvania , Estaciones del Año , Espectrofotometría , Factores de Tiempo , Clima TropicalRESUMEN
The study of long-distance migration provides insights into the habits and performance of organisms at the limit of their physical abilities. The Arctic tern Sterna paradisaea is the epitome of such behavior; despite its small size (<125 g), banding recoveries and at-sea surveys suggest that its annual migration from boreal and high Arctic breeding grounds to the Southern Ocean may be the longest seasonal movement of any animal. Our tracking of 11 Arctic terns fitted with miniature (1.4-g) geolocators revealed that these birds do indeed travel huge distances (more than 80,000 km annually for some individuals). As well as confirming the location of the main wintering region, we also identified a previously unknown oceanic stopover area in the North Atlantic used by birds from at least two breeding populations (from Greenland and Iceland). Although birds from the same colony took one of two alternative southbound migration routes following the African or South American coast, all returned on a broadly similar, sigmoidal trajectory, crossing from east to west in the Atlantic in the region of the equatorial Intertropical Convergence Zone. Arctic terns clearly target regions of high marine productivity both as stopover and wintering areas, and exploit prevailing global wind systems to reduce flight costs on long-distance commutes.