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Relationship between effective and demographic population size in continuously distributed populations.

ABSTRACT: Genetic monitoring of wild populations can offer insights into demographic and genetic information simultaneously. However, widespread application of genetic monitoring is hindered by large uncertainty in the estimation and interpretation of target metrics such as contemporary effective population size, N_e . We used four long-term genetic and demographic studies (?9 years) to evaluate the temporal stability of the relationship between N_e and demographic population size (N_c ). These case studies focused on mammals that are continuously distributed, yet dispersal-limited within the spatial scale of the study. We estimated local, contemporary N_e with single-sample methods (LDNE, Heterozygosity Excess, and Molecular Ancestry) and demographic abundance with either mark-recapture estimates or catch-per-unit effort indices. Estimates of N_e varied widely within each case study suggesting interpretation of estimates is challenging. We found inconsistent correlations and trends both among estimates of N_e and between N_e and N_c suggesting the value of N_e as an indicator of N_c is limited in some cases. In the two case studies with consistent trends between N_e and N_c , F_IS was more stable over time and lower, suggesting F_IS may be a good indicator that the population was sampled at a spatial scale at which genetic structure is not biasing estimates of N_e . These results suggest that more empirical work on the estimation of N_e in continuous populations is needed to understand the appropriate context to use LDNe as a useful metric in a monitoring programme to detect temporal trends in either N_e or N_c .

SUBMITTER: Pierson JC

PROVIDER: S-EPMC6050178 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Relationship between effective and demographic population size in continuously distributed populations.

Pierson Jennifer C JC Graves Tabitha A TA Banks Sam C SC Kendall Katherine C KC Lindenmayer David B DB

Evolutionary applications 20180520 7

Genetic monitoring of wild populations can offer insights into demographic and genetic information simultaneously. However, widespread application of genetic monitoring is hindered by large uncertainty in the estimation and interpretation of target metrics such as contemporary effective population size, Ne . We used four long-term genetic and demographic studies (≥9 years) to evaluate the temporal stability of the relationship between Ne and demo ...[more]

PMID: 30026804

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Relationship between effective and demographic population size in continuously distributed populations.

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Relationship between effective and demographic population size in continuously distributed populations.

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