DOI: 10.5061/dryad.n8c57
title: Data from: An assessment of the reliability of quantitative genetics estimates in study systems with high rate of extra-pair reproduction and low recruitment

description: Quantitative genetics approaches, and particularly animal models, are
 widely used to assess the genetic (co)variance of key fitness related
 traits and infer adaptive potential of wild populations. Despite the
 importance of precision and accuracy of genetic variance estimates and
 their potential sensitivity to various ecological and population specific
 factors, their reliability is rarely tested explicitly. Here, we used
 simulations and empirical data collected from an 11-year study on tree
 swallow (Tachycineta bicolor), a species showing a high rate of extra-pair
 paternity and a low recruitment rate, to assess the importance of identity
 errors, structure and size of the pedigree on quantitative genetic
 estimates in our dataset. Our simulations revealed an important lack of
 precision in heritability and genetic-correlation estimates for most
 traits, a low power to detect significant effects and important
 identifiability problems. We also observed a large bias in heritability
 estimates when using the social pedigree instead of the genetic one
 (deflated heritabilities) or when not accounting for an important cause of
 resemblance among individuals (for example, permanent environment or brood
 effect) in model parameterizations for some traits (inflated
 heritabilities). We discuss the causes underlying the low reliability
 observed here and why they are also likely to occur in other study
 systems. Altogether, our results re-emphasize the difficulties of
 generalizing quantitative genetic estimates reliably from one study system
 to another and the importance of reporting simulation analyses to evaluate
 these important issues.
description: Genetic pedigree of the
 southern Quebec tree swallow populationGenetic pedigree
 constructed with Cervus based on microsatellite data.GeneticPedigree.txtSocial pedigree of the southern Quebec tree swallow populationSocial pedigree based on field observations.SocialPedigree.txtEmpirical dataset of the southern Quebec tree swallow populationEmpirical dataset used to estimate and simulate quantitative genetic parameters. Column headings are individual ids (ID), year (YEAR), stade (STADE),brood ids (BROOD), sex (SEX), age (AGE), female age (AGEF), wing length (WL), Julian day for wing length measurement (WLJJ), body mass (MASS), brood number for body mass measurement (MASSNCOUV), Julian day for body mass measurement (MASSJJPONTE), hour for body mass measurement (MASSHOUR), tarsus length (TARSUS), laying date (LD), clutch size (CS), incubation duration (INC), nestling body mass (MASSJ16), nestling wing length (WLJ16), nestlong tarsus length (TARSEJ16), hour of measurement for nestling measurement (HOUR.J16), Julian day for nestling measurement (JJ.J16).EmpiricalDataset.txtSimulation results for the southern Quebec tree swallow populationSimulation results for the southern Quebec tree swallow population. Column headings are simulated values of genetic/environmental correlation and heritability (SIM_covA, SIM_covE, SIM_H), repetition number (N), pedigree type (PED), set of simulated data (SET; 1: simple univariate model; 2: multivariate model; 3a: univariate model with multiple sources of variance; 3b: univariation model without accounting for an important source of variance), analysis type (MOD), trait category (CAT; C1: morphological; C2: reproductive; C3: nestling), trait (TRAIT), and results from animal models (all other columns).ResultsSimulations.txt