genetic variation

dustinmeeg

Predicting evolutionary responses to climate change in the sea

Authors: Philip L Munday, Rober R Warner, Keyne Munro, John M Pandolfi and Dustin J Marshall

Published in: Ecology Letters, volume 16, issue 12 (December 2013)

Abstract

An increasing number of short-term experimental studies show significant effects of projected ocean warming and ocean acidification on the performance on marine organisms. Yet, it remains unclear if we can reliably predict the impact of climate change on marine populations and ecosystems, because we lack sufficient understanding of the capacity for marine organisms to adapt to rapid climate change.

In this review, we emphasise why an evolutionary perspective is crucial to understanding climate change impacts in the sea and examine the approaches that may be useful for addressing this challenge.

We first consider what the geological record and present-day analogues of future climate conditions can tell us about the potential for adaptation to climate change. We also examine evidence that phenotypic plasticity may assist marine species to persist in a rapidly changing climate. We then outline the various experimental approaches that can be used to estimate evolutionary potential, focusing on molecular tools, quantitative genetics, and experimental evolution, and we describe the benefits of combining different approaches to gain a deeper understanding of evolutionary potential.

Our goal is to provide a platform for future research addressing the evolutionary potential for marine organisms to cope with climate change.

Full paper

Munday PL, Warner RR, Munro  K, Pandolfi JM, Marshall DJ (2013) Predicting evolutionary responses to climate change in the sea. Ecology Letters,  16: 1488–1500  PDFPDF 371 KB doi:10.1111/ele.12185

dustinmeeg

Published paper: Minimal increase in genetic diversity enhances predation resistance

Authors: Kai S Koh, Carsten Matz, Chuan H Tan, Hoang L Le, Scott A Rice, Dustin J Marshall, Peter D Steinberg and Steffan Kjelleberg

Published in: Molecular Ecology, volume 21, issue 7, doi: 10.1111/j.1365-294X.2011.05415.x

Abstract

The importance of species diversity to emergent, ecological properties of communities is increasingly appreciated, but the importance of within-species genetic diversity for analogous emergent properties of populations is only just becoming apparent.

Here, the properties and effects of genetic variation on predation resistance in populations were assessed and the molecular mechanism underlying these emergent effects was investigated.

Using biofilms of the ubiquitous bacterium Serratia marcescens, we tested the importance of genetic diversity in defending biofilms against protozoan grazing, a main source of mortality for bacteria in all natural ecosystems.

S. marcescens biofilms established from wild-type cells produce heritable, stable variants, which when experimentally combined, persist as a diverse assemblage and are significantly more resistant to grazing than either wild type or variant biofilms grown in monoculture.

This diversity effect is biofilm-specific, a result of either facilitation or resource partitioning among variants, with equivalent experiments using planktonic cultures and grazers resulting in dominance by a single resistant strain.

The variants studied are all the result of single nucleotide polymorphisms in one regulatory gene suggesting that the benefits of genetic diversity in clonal biofilms can occur through remarkably minimal genetic change.

The findings presented here provide a new insight on the integration of genetics and population ecology, in which diversity arising through minimal changes in genotype can have major ecological implications for natural populations.

Full paper

Koh KS, Matz C, Tan CH, Le HL, Rice SA, Marshall DJ, Steinberg PP, Kjelleberg S (2012) Minimal increase in genetic diversity enhances predation resistance. Molecular Ecology 21: 1741–1753 PDFPDF 681 KB doi: 10.1111/j.1365-294X.2011.05415.x