Will plant movements keep up with climate change?

Richard T. Corlett and David A. Westcott. Trends in Ecology and Evolution 28(8): 482-488. DOI:10.1016/j.tree.2013.04.003. Will plant movements keep up with climate change?

It's a plant moving. Look, do you have any idea how hard it is to find a picture every week?

This plant can move fast enough… From Wikipedia


Will Pearse

Will Pearse

I picked this paper (out of Lynsey’s selection) because I had a long chat with someone about this at ESA. We concluded then that we didn’t really know whether plants could move fast enough, and to be honest that’s pretty much the conclusion I came to at the end of this review.

Box 4 of the review lists outstanding problems that include “ignorance of the factors that currently limit species ranges”, “largely unknown to what extent plants can acclimate to climate change”, and a number of other factors. The section “can plants track climate change?” lasts only two paragraphs – we apparently have no idea whether plants can track climate change or not. The authors give a number of (for what it’s worth, quite reasonable) reasons they probably can’t, but I think they’d agree that we don’t actually know. Frankly, I’m slightly shocked that we don’t know more about this.

I’m not convinced that animal-dispersed species are necessarily going to fare much better in the face of climate change. This assumes that animals with larger territories are going to move more easily (not necessarily true), particularly given we don’t fully understand the mechanisms by which species would shift their ranges. An animal that eats fruits that moves when it’s hungry is not going to disperse that fruit polewards, because it’s hungry and hasn’t eaten that fruit!

Long-distance dispersal as a mechanism by which individuals trapped in a sea of bad habitat can save the species is an interesting idea. I think this would benefit from a simulation study, but I sense it would require species to be able to colonise in the face of a quite severe numerical disadvantage (small number of immigrants, lots of incumbents). Still, this is a nice idea I’d like to think about for longer…


Lynsey McInnes

Lynsey McInnes

This is a funny paper. On the one hand, a very useful, succinct review of the different factors involved in thinking about how plants might respond to climate change and why this is of interest to ecologists/conservation scientists/mankind and on the other hand, a frustratingly on-the-fence expose of plant movement research to date and its likely next steps.

The authors undoubtedly do a great job in summarizing many recent studies (check out the reference list, its stacked with refs from post 2010). This subject is most definitely timely and popular. And yet it seems we don’t know much. For example, conclusive answers are absent for questions such as what determines a plant species’ current range? How much more range could a species occupy with unlimited dispersal/removing other species/new climates? Is this period of climate change different to past ones (cities in the way, etc.)? The author’s box 4 neatly summarizes the extent of our lack of knowledge!

I got to the end of the paper and found myself wondering (a bit like last week), should we worry? Or should we worry in a more focused way? Does the identity of individual plant species matter as long as the ecosystem is still functioning healthily? If you are a ‘rubbish’ species, has your time come? Perversely, I do just find the outstanding questions listed in box 4 of interest in and of themselves, but firmly, firmly believe that for conservation purposes, they are not the correct ones to be focusing on. I’m not a conservation scientist so I’m allowed (have allowed myself) to ponder these questions, but if wanted to be practical, I reckon we need to think more about functional types (mentioned in box 1), more about corridors to facilitate movement, more about redundancy, more about … ?

Can we ever know – ‘Will plant movements keep up with climate change?’ Seems like this is not a yes or no question. It will depend on the specific set of traits the plant species has/the environment it is found in/the interactions with other species (plants, dispersers, pollinators) it has now and could have in the future? Different camps want an answer for different reasons. Generalities seem to be in place already (and are well-summarised in the paper). However, if we want to conserve species or functions, we need more than these generalities, it seems. If want to use this broad question to learn some fundamentals on the biology of plants, my suggestion would be we need more of everything: more field studies, more theory and perhaps most importantly more of a recognition and exploration of interacting forces: a bit of evolution, a few influential abiotic factors, one or two key biotic interactions, a whole host of more minor ones, across and within trophic levels, some anthropogenic effects, short- and long-distance dispersal and this whole shebang playing out against a shifting climate.

I think the paper left me unsatisfied as it was pitched too broad and thus felt too shallow. What are these authors interested in? What piece of the puzzle will they tackle? Ja, perhaps that’s unfair to ask of from a review, but I’m curious anyway.

Finally – I did very much appreciate this line from the paper: ‘The involvement of government agencies, nongovernmental organizations, and citizen-science networks will be essential, given the focus of academic science on novelty.’

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About will.pearse
Ecology / evolutionary biologist

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