Tachycineta

While Golden Swallows are endemic to the Greater Antilles islands of Jamaican and Hispaniola, the Tachycineta genus to which they belong is composed of nine species whose collective ranges extend from Alaska, USA to Tierra del Fuego, Argentina (Turner and Rose 1989), making them the largest genus of endemic New World swallows (Sibley and Monroe 1990). The most recent phylogeny by Cerasale et al. (2012) groups T. euchrysea and T. cyaneoviridis into a North American clade as sisters to the widespread continental species, the Violet-green Swallow (T. thalassina). This hypothesis differs slightly from an earlier phylogenetic reconstruction by Whittingham et al. (2002) that placed T. thalassina only as a sister to T. euchrysea. Interestingly, the distribution of T. thalassina on the mainland spans the combined latitudinal ranges of T. cyaneoviridis and T. euchrysea, while its breeding grounds on the Mexican mainland are comparable in altitudinal variation to those used by T. euchrysea on Hispaniola (BirdLife International 2015, eBird 2015).  The temperate-nesting congeners, in particular the Tree Swallow (T. bicolor), have been much more extensively studied in comparison to their tropical counterparts (Martin 1996, Jones 2003). Moreover, the two tropical island-endemic species (T. cyaneoviridis and T. euchrysea) are only beginning to show up on the scientific radar (Allen 1996, Townsend et al. 2008, Graves 2014), and their life history strategies – once better understood – will be invaluable to understanding avian life history theory across a genus of birds that is collectively distributed throughout the entirety of the Western Hemisphere.

 

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Existen nueve especies dentro del género Tachycineta, distribuidas a lo largo del Hemisferio Oeste, desde Alaska hasta las costas de Patagonia. Algunas especies son importantes migradoras, mientras que otras tienen distribuciones extremadamente locales. Algunas son tropicales, otras templadas. Anidan desde elevaciones mayores de 2100 metros en cadenas montañosas del Caribe al nivel del mar en los llanos costeros. Las golondrinas del género Tachycineta demuestran comportamientos y estrategias de vida extremadamente distintas entre sí; sin embargo, también presentan similitudes notables.