Inferring microevolution from museum collections and resampling: lessons learned from Cepaea

Małgorzata Ożgo; Thor-Seng Liew; Nicole B Webster; Menno Schilthuizen

doi:10.7287/peerj.preprints.2304v1

Inferring microevolution from museum collections and resampling: lessons learned from Cepaea

Małgorzata Ożgo¹, Thor-Seng Liew^2,3,4, Nicole B Webster^3,4, Menno Schilthuizen ^2,3,4

1 Dept. of Evolutionary Biology, Kazimierz Wielki University, Bydgoszcz, Poland

2 Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia

3 Institute Biology Leiden, Leiden Univerisity, Leiden, The Netherlands

4 Endless Forms Group, Naturalis Biodiversity Center, Leiden, The Netherlands

DOI: 10.7287/peerj.preprints.2304v1

Published: 2016-07-20
Accepted: 2016-07-20

Subject Areas: Environmental Sciences, Evolutionary Studies, Zoology
Keywords: HIREC, snails, natural selection, natural history collections, colour polymorphism, time series, evolutionary trends, population genetics

Copyright: © 2016 Ożgo et al.
Licence: This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.

Cite this article: Ożgo M, Liew T, Webster NB, Schilthuizen M. 2016. Inferring microevolution from museum collections and resampling: lessons learned from Cepaea. PeerJ Preprints 4:e2304v1 https://doi.org/10.7287/peerj.preprints.2304v1

Abstract

Studies documenting Human-Induced Rapid Evolutionary Change (HIREC) routinely compare contemporary allele or morph frequency distributions with historical baselines. All too often, this involves the re-sampling of a population that was sampled at a single time point in the past. However, year-to-year fluctuations in magnitude and direction of evolutionary response may make such studies prone to erroneous conclusions, where long-term evolutionary trends are inferred from what in fact are short-term fluctuations. Here, we explore this problem by re-sampling three Dutch populations of the land snail Cepaea nemoralis, whose shell colour polymorphism is known to be under thermal and predatory selection. Each of these three populations was originally sampled in at least two different years in the past. We show that conclusions on evolutionary change are strongly dependent on which of the historical sample dates is used for comparison with the contemporary sample. Our study highlights the fact that year-to-year variation in allele frequencies may often be so strong that a simple two-point comparison is unreliable to detect long-term evolutionary trends.