Productivity increases with species diversity: 150 years later, research proves Darwin prediction

May 13, 2013

Environments containing species that are distantly related to one another are more productive than those containing closely related species, according to new research from the University of Toronto Scarborough (UTSC).

The experimental result from Marc William Cadotte confirms a prediction made by in On the , first published in 1859. Darwin had said that a plot of land growing distantly related grasses would be more productive than a plot with a single of grass.

Since then, many experiments have shown that multi-species plots are more productive. Cadotte's experiment showed for the first time that species with the greatest evolutionary distance from one another have the greatest .

"If you have two species that can access different resources or do things in different ways, then having those two species together can enhance species function. What I've done is account for those differences by accounting for their ," Cadotte says.

Cadotte grew 17 different plants in various combinations of one, two, or four species per plot. As in previous experiments, he found that multi-species plots produced more . But when he analyzed the results he also found that combinations of plants that were distantly related to one another were more productive than combinations of plants that were closely related. So, for instance, a plot planted with goldenrod and the closely related black-eyed susan wasn't as productive as a plot with goldenrod and the more distantly related bluestem .

What's going on isn't mysterious, Cadotte says. Distantly related plants are more likely to require different resources and to fill different environmental niches – one might need more nitrogen, the other more phosphorus; one might have shallow roots, the other deep roots. So rather than competing with one another they complement one another.

What's interesting about his result is that evolutionary distance is all you need to know to predict productivity. The result suggests that as plant species disappear the Earth will become less productive, and plants will draw even less carbon from the atmosphere, possibly increasing the rate of global warming.

On the other hand, the results could give a valuable tool to conservation efforts. Environmentalists trying to restore damaged habitats could use the information to help them pick which combinations of species to introduce.

This research is published in the upcoming edition of the Proceedings of the National Academy of Sciences (PNAS).

Explore further: Human sense of fairness evolved to favor long-term cooperation

More information: Experimental evidence that evolutionarily diverse assemblages result in higher productivity, www.pnas.org/cgi/doi/10.1073/pnas.1301685110

Related Stories

Plant diversity is key to maintaining productive vegetation

May 03, 2012

Vegetation, such as a patch of prairie or a forest stand, is more productive in the long run when more plant species are present, a new University of Minnesota study shows. The unprecedented long-term study of plant biodiversity ...

Recommended for you

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

xeb
3 / 5 (3) May 14, 2013
Would that hold for "information processing phase-space" (cognitive systems)? :)
Not much diversity left to experiment on - there is about a hundred still-autonomous (not mixing, diverse) human populations left, all the rest is already united (by technologies, communication, economy, laws etc.). And dolphins or elephants or any other cognitive partners here on Earth .. - we wouldn't have patience to understand what is that they want to be productive about (in cognitive phase-sp.).
But maybe there is a lesson for biology like that above (i.e. cognition and meta-networks not taken into consid.):
Look, thanks to all the imperia, subjugations, slavery, holocausts, cultural-cide etc., we have pruned all the different human ways of intaking energy from different niches (e.g. how to feed without gun in australia vs alaska), and now it seems even better: this leviathan of Global Civilization eats much more resources for a year than all the previous diverse mankind for millenia.
:)
xeb
2.3 / 5 (3) May 14, 2013
So, the skill-levels for "conservation efforts" are:
- noob: more productivity for me now
- novice: more productivity, same diversity
- apprentice: same productivity, same diversity
- [locked yet] master: same productivity, diversity rising
- [locked yet] god-mode: less productivity, more diversity (e.g.: "All cognitive events are now to be transfered into planck-scale equivalents, so there would be room and time for more stories ")
- son-of-god-spontaneous: C'mon eat me now, so that u may live
- [locked yet] son-of-god-premeditate: I will choose the shortest sequence of give-outs, each supporting the development of entities with higher-possible conservation skills, and all of them (steps of this strategy) resulting in maximal achievable contibution to diversity of pro-conservationistic (non-expansive) identities
[...] In other words:
Evolutionary strategies are not authentically friendly for diversity.
Pro-diverstity has lover priority then our own evolution in our current strategies.