Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/49680
Title: Apparent selective advantage of leucism in a coastal population of Southern caracaras (Falconidae)
Authors: Edelaar, Pim, Donázar, José A., Soriano, Matías, Santillán, Miguel Angel, Gónzalez-Zevallos, Diego, García Borboroglu, Pablo, Lisnizer, Nora, Gatto, Alejandro Javier, Agüero, María Laura, Passera, Carlos A.
Keywords: Albinism
Caracara plancus
colour
inbreeding
leucism
polymorphism
Issue Date: Feb-2011
Publisher: Evolutionary Ecology
Abstract: Background: Southern caracaras are medium-sized raptors with a large range stretching to the southern tip of South America. An aberrant, leucistic plumage is found commonly along the coast of Chubut Province (Patagonia, Argentina). Leucistic birds do not produce dark melanin in their feathers. However, they are not albinos because their eyes are not red. No genetic studies of caracara plumages are known. Hypothesis: The high frequency of leucistic birds in Chubut Province arises because of natural selection. Methods: Map the distribution of leucistic individuals relative to normal individuals. Combine a variety of anecdotal natural history observations, collected over 20 years, into a logical inference. Observations: Leucistic caracaras were found only along a 250-km stretch of rocky oceanic islands and continental outcrops with large seabird colonies in Chubut Province. In the rest of their range, Southern caracaras have dark plumage. Where they do occur, leucistic birds are frequent and co-occur with dark-plumaged birds. Intermediate individuals, presumably heterozygotes, exist. Leucism is not related to age or sex. Leucistic individuals are restricted to a particular habitat. Gene flow has not homogenized the coastal and inland populations. Results: Leucism is not simply due to inbreeding producing more homozygous individuals. Leucism is not due to genetic drift. Leucism is not an environmental effect on individual physiology or development. Leucism is not a transient (plastic) phenomenon. Where they occur frequently, leucistic Southern caracaras are apparently favoured by natural selection, either directly or by pleiotropy
Publisher version (URL): http://www.evolutionary-ecology.com/issues/v13/n02/hhar2639.pdf
URI: http://hdl.handle.net/10261/49680
Citation: Evolutionary Ecology Research, 2011, 13: 187–196
Appears in Collections:(EBD) Artículos
Files in This Item:
File Description SizeFormat 
hhar2639.pdf347,57 kBAdobe PDFView/Open
Show full item record
 
CSIC SFX LinksSFX Query

Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.