Post provided by Laura Graham

Song sparrows show substantial genetic variation in multiple life-history traits. Application of ‘genetic group animal models’ show that this is partly due to genetic effects of immigrants © Jane Reid
Song sparrows show genetic variation in multiple life-history traits. Application of ‘genetic group animal models’ show this is partly due to genetic effects of immigrants ©Jane Reid

Understanding how wild populations respond and adapt to environmental change is a key question in evolutionary biology. To understand this, we need to be able to separate genetic and environmental effects on phenotypic variation. Statistical ‘animal models’, which can do just this, have revolutionised the field of quantitative genetics. A lack of full knowledge of individual pedigrees can lead to severe bias in quantitative genetic parameter estimates though – particularly when genetic values for focal traits vary non-randomly in unknown parents.

In the Journal of Animal Ecology ‘How To…’ paper “Accounting for genetic differences among unknown parents in microevolutionary studies: how to include genetic groups in quantitative genetic animal models”, the extent of this bias is highlighted. Matthew Wolak and Quantitative Ecology 2018 keynote speaker Jane Reid show how genetic group methods – a technique developed in agricultural science – can be employed to minimise it.

Simulations from Wolak and Reid 2016 highlighting the bias in animal models with unknown parents.
Simulations from Wolak and Reid 2016 highlighting the bias in animal models with unknown parents.

To help genetic group animal models become a standard part of the evolutionary biologist’s toolbox; Wolak and Reid provide extensive tutorials and an R package (nadiv) to apply the method.

This ‘How To…’ paper is a must read for anyone wishing to understand the effects of environmental change on microevolutionary processes. It provides the tools and advice necessary to get on and do these analyses (given the appropriate dataset!).

To find out more about, read the full Journal of Animal Ecology article ‘Accounting for genetic differences among unknown parents in microevolutionary studies: how to include genetic groups in quantitative genetic animal models

 This article is part of the BES cross-journal ‘Statistical Ecology Virtual Issue’. All articles in this Virtual Issue will be available for a limited time.

You can find more Journal of Animal Ecology ‘How To…’ articles here.