Limits...
Sex-biased dispersal of a frog (Odorrana schmackeri) is affected by patch isolation and resource limitation in a fragmented landscape.

Wang Y, Lane A, Ding P - PLoS ONE (2012)

Bottom Line: The effects of four island attributes and two potential impact factors on the pattern of sex-biased dispersal were examined.We found that the extent of isolation from the mainland and the number of breeding sites both showed a negative correlation with female biased dispersal, such that the closer an island is to the mainland the more likely it is to display female biased dispersal, and the more breeding sites on an island the more male immigrants.Based on these results, we conclude that geographic isolation and limited breeding resources are the most likely explanation for the patterns of dispersal observed in this fragmented population of amphibians.

View Article: PubMed Central - PubMed

Affiliation: The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, China.

ABSTRACT
Sex-biased dispersal is widespread in the animal kingdom and is affected by numerous factors including mating system, social factors and environmental conditions. Unlike birds and mammals, there is no common trend in amphibians and explaining the direction and degree of sex-biased dispersal in species-specific cases is difficult. We conducted a study on dispersal of the Chinese piebald odorous frog (Odorrana schmackeri) in a fragmented landscape associated with dam construction. Ten microsatellite loci were used to analyze 382 samples sourced from 14 fragmented 'islands'. Assignment tests indicated a significant pattern of female-biased dispersal on one island with inconsistencies in the strength and direction of this pattern between nearby islands. The effects of four island attributes and two potential impact factors on the pattern of sex-biased dispersal were examined. We found that the extent of isolation from the mainland and the number of breeding sites both showed a negative correlation with female biased dispersal, such that the closer an island is to the mainland the more likely it is to display female biased dispersal, and the more breeding sites on an island the more male immigrants. Based on these results, we conclude that geographic isolation and limited breeding resources are the most likely explanation for the patterns of dispersal observed in this fragmented population of amphibians.

Show MeSH

Related in: MedlinePlus

Mean AIc value for male and female of Odorrana schmackeri.The results demonstrate significant female-biased dispersal. * represent significant differences between sexes with Mann Whitney U test after false discovery rate correction.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3475718&req=5

pone-0047683-g002: Mean AIc value for male and female of Odorrana schmackeri.The results demonstrate significant female-biased dispersal. * represent significant differences between sexes with Mann Whitney U test after false discovery rate correction.

Mentions: Corrected assignment indices (AIc) indicate that nine of the 14 islands display female-biased dispersal (negative score for females, positive for males) while the remaining five islands display male-biased dispersal (negative score for males, positive score for females). Island 13 (P = 0.015) showed a significant degree of female-biased dispersal after FDR correction, whereas sex-biased dispersal on the other islands was not significant according to Mann Whitney U tests (Figure 2). The overall dispersal result when considering pooled data from all 14 island populations was male-biased, though this was not significant, as AIc values were similar at −0.016 and 0.014 for males and females respectively (P = 0.749).


Sex-biased dispersal of a frog (Odorrana schmackeri) is affected by patch isolation and resource limitation in a fragmented landscape.

Wang Y, Lane A, Ding P - PLoS ONE (2012)

Mean AIc value for male and female of Odorrana schmackeri.The results demonstrate significant female-biased dispersal. * represent significant differences between sexes with Mann Whitney U test after false discovery rate correction.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3475718&req=5

pone-0047683-g002: Mean AIc value for male and female of Odorrana schmackeri.The results demonstrate significant female-biased dispersal. * represent significant differences between sexes with Mann Whitney U test after false discovery rate correction.
Mentions: Corrected assignment indices (AIc) indicate that nine of the 14 islands display female-biased dispersal (negative score for females, positive for males) while the remaining five islands display male-biased dispersal (negative score for males, positive score for females). Island 13 (P = 0.015) showed a significant degree of female-biased dispersal after FDR correction, whereas sex-biased dispersal on the other islands was not significant according to Mann Whitney U tests (Figure 2). The overall dispersal result when considering pooled data from all 14 island populations was male-biased, though this was not significant, as AIc values were similar at −0.016 and 0.014 for males and females respectively (P = 0.749).

Bottom Line: The effects of four island attributes and two potential impact factors on the pattern of sex-biased dispersal were examined.We found that the extent of isolation from the mainland and the number of breeding sites both showed a negative correlation with female biased dispersal, such that the closer an island is to the mainland the more likely it is to display female biased dispersal, and the more breeding sites on an island the more male immigrants.Based on these results, we conclude that geographic isolation and limited breeding resources are the most likely explanation for the patterns of dispersal observed in this fragmented population of amphibians.

View Article: PubMed Central - PubMed

Affiliation: The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, China.

ABSTRACT
Sex-biased dispersal is widespread in the animal kingdom and is affected by numerous factors including mating system, social factors and environmental conditions. Unlike birds and mammals, there is no common trend in amphibians and explaining the direction and degree of sex-biased dispersal in species-specific cases is difficult. We conducted a study on dispersal of the Chinese piebald odorous frog (Odorrana schmackeri) in a fragmented landscape associated with dam construction. Ten microsatellite loci were used to analyze 382 samples sourced from 14 fragmented 'islands'. Assignment tests indicated a significant pattern of female-biased dispersal on one island with inconsistencies in the strength and direction of this pattern between nearby islands. The effects of four island attributes and two potential impact factors on the pattern of sex-biased dispersal were examined. We found that the extent of isolation from the mainland and the number of breeding sites both showed a negative correlation with female biased dispersal, such that the closer an island is to the mainland the more likely it is to display female biased dispersal, and the more breeding sites on an island the more male immigrants. Based on these results, we conclude that geographic isolation and limited breeding resources are the most likely explanation for the patterns of dispersal observed in this fragmented population of amphibians.

Show MeSH
Related in: MedlinePlus