44 research outputs found
Sexual selection in the house sparrow, Passer domesticus
(1) This study investigated the maintenance of variation in the black throat patch or 'badge' of the male house sparrow. This sexually dimorphic trait is thought to be a sexually selected ornament, with previous workers providing evidence of a role in both mate choice of males by females and male-male competition. The study was conducted in 1995 and 1996 in a closed population of approximately 40 breeding pairs on Lundy Island, in the Bristol Channel, England.;(2) Genetic analysis of paternity using PCR-based microsatellite genotyping revealed a very low level of extra-pair paternity in both years and no intra-specific brood parasitism. Just three extra-pair chicks (1.0% offspring in 2.5% of broods) were discovered among 305 chicks in 112 broods. This low frequency of extra-pair paternity is significantly lower than the rates reported in three other populations of house sparrows and provides further evidence for a low level of extra-pair paternity occurring in isolated populations.;(3) The very low frequency of extra-pair paternity in this population allowed an examination of the costs and benefits that may be gained by a female exhibiting a preference for a large-badged male, unconfounded by the effects of extra-pair behaviour.;(4) The direct benefits models of sexual selection were tested by assessing male help in provisioning chicks at the nest. Counter to the predictions of these models, large-badged males contributed relatively fewer feeds than males with smaller badges. Similarly, large-badged males, and the females that chose them as maters, had lower annual fecundity and were predicted to recruit significantly less offspring into the breeding population.;5) A female preference might be driven by the indirect benefits of obtaining genes for either viability or attractiveness for the female's offspring. A cross-fostering experiment revealed that variation in badge size had a large environmental component with a strong correlation between offspring badge size and that of their foster father, with no discernible additive genetic variation. This mechanism for the determination of badge size cannot support a process of Fisherian 'runaway' selection and is consistent with those models which require a sexual ornament to be phenotypically plastic and therefore provide an honest signal
DatasetsMariette&Griffith
daily data set of pair synchrony between day 6 and 14 and mean data set per pair over that period. variable names are as described in the paper. a refrence ID allows to link the two data sets
Price_Griffith_tables_ESM from Open cup nests evolved from roofed nests in the early passerines
Nest data for Australian passerine species (table S1) and world passerine families (table S2), and results of BiSSE analyses (table S3
Appendix A. Figure of settlement patterns and nest box availability at different densities throughout the breeding season.
Figure of settlement patterns and nest box availability at different densities throughout the breeding season
Geographical variation in bill colour in the Long-tailed Finch: evidence for a narrow zone of admixture between sub-species
<p>The Long-tailed Finch (<i>Poephila acuticauda</i>) is endemic to Australia’s northern tropics and comprises two sub-species differentiated by bill colour: yellow in the western sub-species <i>acuticauda</i> and red in the eastern sub-species <i>hecki</i>. We present an extensive survey of bill colour variation across the range of the Long-tailed Finch (more than 700 individuals collected across nearly 1500 km of range). Geographic clinal analysis using bill reflectance spectrophotometry data suggests that the greatest extent of bill colour admixture is only ~150 km wide and is centred approximately 50 km west of Katherine, Northern Territory (14.5° S, 132.3° E). Variation in bill colour is generally low outside of this zone, and across widely distributed allopatric populations of both sub-species. However, the best-fit clinal model supports a pattern of asymmetrical introgression of bill colour from the east into the west. The narrow geographic width of bill colour admixture between Long-tailed Finch sub-species and the estimated timing of secondary contact (14–21 kya) suggests a role for selection acting against hybrids and/or parentals in maintaining sub-species as independently evolving populations.</p
Blue tit nest sizes for genetic mother-daughter pairs
Nest sizes (recorded as fraction of standardised nest box filled) of blue tit daughters and their genetic mothers, as recorded by SCG in Wytham Woods, Oxfordshire, UK in 2001-200
Final R code used for analysis 2
The R code that I wrote to analyse different factors controlling the nest size of blue tits in Wytham Woods, UK during the 2001-2003 breeding seasons using the data files attache
location
This file contains the data for the descriptive component of the paper, characterising temperatures in different types of nest and locations in vegetation as described in the paper