The Eco-evolutionary Dilemma

This is a guest post by Associate Editor Richard P. Shefferson, who recently also guest-edited a Special Feature for Journal of Ecology.

The most recent issue of Journal of Ecology (July 2015) includes a Special Feature on Eco-evolutionary Dynamics in Plants. The Special Feature consists of five research papers and an editorial, and the themes covered include genetic variation (Shaw et al., 2015, Lamit et al., 2015), adaptive plasticity (Metcalf et al., 2015), community structure (Lamit et al., 2015), herbivore evolution (Utsumi, 2015), inbreeding (Shaw et al., 2015), density dependence (Williams et al., 2015, Metcalf et al., 2015)and climate change (Williams et al., 2015), all from the eco-evo perspective. Although this is not the first special issue of a major ecological journal on this topic, it is nonetheless the first to highlight the role of and opportunities offered by plant ecological research in this rather new field.

The essential realization that has led to the development of this sub-discipline of evolutionary ecology is that evolution is not necessarily slow, as has often been supposed by both ecologists and evolutionary biologists alike, but that it may be – and actually often is – quite rapid. In fact, as many others have pointed out, it is rapid enough to occur at the same pace as many other ecological processes (Hairston Jr. et al., 2005). This overlapping timescale yields more questions than answers, and causes a fundamental reassessment of assumptions in ecological and evolutionary analyses (Shefferson and Salguero-Gómez, 2015). For example, phylogenetic analysis assumes that macroevolution is a fundamentally slow process that does not feed back onto ecological systems except at long timescales. But, as we now know, this may not be fair. How do overlapping timescales affect our understanding of macroevolution (Shefferson and Salguero-Gómez, 2015)?

The roots of eco-evolutionary dynamics are diverse, and rather than present a list of names and their contributions, I will direct the reader both to the editorial for this special feature (Shefferson and Salguero-Gómez, 2015), which includes a short history of the field, and a few other important papers with some of the history detailed (Reznick, 2013, Pelletier et al., 2009, Hairston Jr. et al., 2005). However, I do wish to use this opportunity to present the contributions to the field of an evolutionary biologist who has exerted a major influence without necessarily being recognized for his importance. That individual is John B. S. Haldane, who is quoted at the beginning of the editorial.

Haldane was most certainly an important evolutionary biologist, known most for his contributions to the Darwinian Synthesis. He is also rather well-known for his staunch support of socialism and communism, his naturalization to India, and his criticism of the influence of money in science. However, among his most interesting writings are those that relate to the speed of evolution. Haldane often thought about how quickly natural selection can act, and suggested that rapid evolution might be quite rare. There were several reasons for this statement, most famously those dealing with the since resolved “Haldane’s dilemma”, which suggested that multiple traits in the same organism were not likely to evolve quickly via natural or even artificial selection because of the requirement of strong, consistent genetic correlations among those traits, combined with potentially harsh selection that would dramatically reduce the overall population growth rate (Haldane, 1957). Theoretical writings such as this and others by Haldane inspired some great research on the speed of evolution, and influenced even conservation via the concept of evolutionary rescue (Haldane, 1939, Carlson et al., 2014). These ideas are very important today, particularly when considered in light of the potential for evolution to interact with ecological processes via eco-evolutionary feedback (Yoshida et al., 2003).

My hope in co-editing this Special Feature is that other evolutionary ecologists will develop new theoretical and empirical systems in order to re-develop the field of evolutionary ecology with the new understanding of the overlapping timescales of ecology and evolution. This is very necessary, particularly because the dilemma facing evolutionary ecologists is not whether or not natural selection can act quickly, as it was in Haldane’s day, but rather that we know that it can and often does act quickly, yet do not understand the resulting consequences.

Rich Shefferson
Special Feature Guest Editor
Associate Editor – Journal of Ecology

References

Carlson, S. M., Cunningham, C. J. & Westley, P. A. H. (2014) Evolutionary rescue in a changing world. Trends in Ecology & Evolution, 29, 521-530.

Hairston Jr., N. G., Ellner, S. P., Geber, M. A., Yoshida, T. & Fox, J. A. (2005) Rapid evolution and the convergence of ecological and evolutionary time. Ecology Letters, 8, 1114-1127.

Haldane, J. B. S. (1939) The effect of variation of fitness. The American Naturalist, 71, 337-349.

Haldane, J. B. S. (1957) The cost of natural selection. Journal of Genetics, 55, 511-524.

Lamit, L. J., Busby, P. E., Lau, M. K., Compson, Z. G., Wojtowicz, T., Keith, A. R., Zinkgraf, M. S., Schweitzer, J. A., Shuster, S. M., Gehring, C. A. & Whitham, T. G. (2015) Tree genotype mediates covariance among diverse communities from microbes to arthropods. Journal of Ecology, 103, 840-850.

Metcalf, C. J. E., Burqhardt, L. & Koons, D. N. (2015) Avoiding the crowds: the evolution of plastic responses to seasonal cues in a density dependent world. Journal of Ecology, 103, 819-828.

Pelletier, F., Garant, D. & Hendry, A. P. (2009) Eco-evolutionary dynamics. Philosophical Transactions of the Royal Society B: Biological Sciences, 364, 1483-1489.

Reznick, D. N. (2013) A critical look at reciprocity in ecology and evolution: introduction to the symposium. The American Naturalist, 181, S1-S8.

Shaw, R. G., Wagenius, S. & Geyer, C. j. (2015) The susceptibility of Echinacea angustifolia to a specialist aphid: eco-evolutionary perspective on genotypic variation and demographic consequences. Journal of Ecology, 103, 809-818.

Shefferson, R. P. & Salguero-Gómez, R. (2015) Eco-evolutionary dynamics in plants: interactive processes at overlapping timescales and their implications. Journal of Ecology, 103, 789-797.

Utsumi, S. (2015) Feeding evolution of a herbivore influences an arthropod community through plants: implications for plant-mediated eco-evolutionary feedback loop. Journal of Ecology, 103, 829-839.

Williams, J. L., Jacquemyn, H., Ochocki, B. M., Brys, R. & Miller, T. E. X. (2015) Life history evolution under climate change and its influence on the population dynamics of a long-lived plant. Journal of Ecology, 103, 798-808.

Yoshida, T., Jones, L. E., Ellner, S. E., Fussmann, G. F. & Hairston Jr., N. G. (2003) Rapid evolution drives ecological dynamics in a predator-prey system. Nature, 424, 303-306.

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One thought on “The Eco-evolutionary Dilemma

  1. I’m currently reading Do Lemmings Commit Suicide? Beautiful Hypotheses and Ugly Facts by Dennis Chitty, and he tells a great story about JBS Haldane which relates to this. I will quote in full:

    “The idea that natural selection might explain the difference between generations was unacceptable then and for some years to come. In 1950 for example at a meeting of the Society for Experimental Biology, John Clarke and I explained what we were up to [studying cyclical population dynamics of voles] and were asked whether we had considered genetic change as a possible explanation. John replied as follows: “My genetic colleagues at Oxford believe this requires too rapid a genetic change, beyond the speed of normal selection.” Thereupon JBS Haldane rose majestically, turned to John and said: “Your Oxford colleagues are quite correct.”

    As Chitty notes, this effectively closed their minds to the idea that natural selection could be playing a role in what they were observing for many years.

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