NONPARAMETRIC ESTIMATION OF NATURAL SELECTION ON A QUANTITATIVE TRAIT USING MARK-RECAPTURE DATA

Abstract Assessing natural selection on a phenotypic trait in wild populations is of primary importance for evolutionary ecologists. To cope with the imperfect detection of individuals inherent to monitoring in the wild, we develop a nonparametric method for evaluating the form of natural selection on a quantitative trait using mark-recapture data. Our approach uses penalized splines to achieve flexibility in exploring the form of natural selection by avoiding the need to specify an a priori parametric function. If needed, it can help in suggesting a new parametric model. We employ Markov chain Monte Carlo sampling in a Bayesian framework to estimate model parameters. We illustrate our approach using data for a wild population of sociable weavers (Philetairus socius) to investigate survival in relation to body mass. In agreement with previous parametric analyses, we found that lighter individuals showed a reduction in survival. However, the survival function was not symmetric, indicating that body mass might not be under stabilizing selection as suggested previously.

[1]  Ciprian M. Crainiceanu,et al.  Bayesian Analysis for Penalized Spline Regression Using WinBUGS , 2005 .

[2]  Bradley P. Carlin,et al.  Bayesian measures of model complexity and fit , 2002 .

[3]  Jerald B. Johnson,et al.  Model selection in ecology and evolution. , 2004, Trends in ecology & evolution.

[4]  R. Mauricio,et al.  Reducing bias in the measurement of selection. , 1997, Trends in ecology & evolution.

[5]  C J Schwarz,et al.  An Extension of the Cormack–Jolly–Seber Model for Continuous Covariates with Application to Microtus pennsylvanicus , 2006, Biometrics.

[6]  Rita Covas,et al.  Stabilizing selection on body mass in the sociable weaver Philetairus socius , 2002, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[7]  C. Crainiceanu,et al.  Semiparametric Regression in Capture–Recapture Modeling , 2006, Biometrics.

[8]  Roger Pradel,et al.  Efficient profile-likelihood confidence intervals for capture-recapture models , 2005 .

[9]  S. J. Arnold,et al.  THE MEASUREMENT OF SELECTION ON CORRELATED CHARACTERS , 1983, Evolution; international journal of organic evolution.

[10]  D. Berrigan,et al.  Strength and tempo of directional selection in the wild , 2001, Proceedings of the National Academy of Sciences of the United States of America.

[11]  D. Ruppert.  Selecting the Number of Knots for Penalized Splines , 2002 .

[12]  M. Rausher.  THE MEASUREMENT OF SELECTION ON QUANTITATIVE TRAITS: BIASES DUE TO ENVIRONMENTAL COVARIANCES BETWEEN TRAITS AND FITNESS , 1992, Evolution; international journal of organic evolution.

[13]  Douglas W. Nychka,et al.  Exploring Fitness Surfaces , 1994, The American Naturalist.

[14]  T. Mitchell-Olds,et al.  REGRESSION ANALYSIS OF NATURAL SELECTION: STATISTICAL INFERENCE AND BIOLOGICAL INTERPRETATION , 1987, Evolution; international journal of organic evolution.

[15]  K. Burnham,et al.  Program MARK: survival estimation from populations of marked animals , 1999 .

[16]  Michael J. Conroy,et al.  Analysis of individual- and time-specific covariate effects on survival of Serinus serinus in north-eastern Spain , 2002 .

[17]  A. N. Arnason,et al.  The estimation of population size, migration rates and survival in a stratified population , 1973, Researches on Population Ecology.

[18]  J. M. Hoekstra,et al.  The Strength of Phenotypic Selection in Natural Populations , 2001, The American Naturalist.

[19]  William A. Link,et al.  Occam's shadow: Levels of analysis in evolutionary ecology--where to next? , 2002 .

[20]  J. Nichols,et al.  Individual quality, survival variation and patterns of phenotypic selection on body condition and timing of nesting in birds , 2005, Oecologia.

[21]  J. Kingsolver,et al.  ESTIMATING SELECTION ON QUANTITATIVE TRAITS USING CAPTURE‐RECAPTURE DATA , 1995, Evolution; international journal of organic evolution.