Tag Archives: landscape

Changing with the Climate

An immature female blue-tailed damselfly (Ischnura elegans)

An immature female blue-tailed damselfly (Ischnura elegans) (Image Credit: Charles J Sharp [CC BY-SA 4.0])

Signatures of local adaptation along environmental gradients in a range-expanding damselfly (Ischnura elegans) (2018) Dudaniec et al., Molecular Ecology http://doi:10.1111/mec.14709

The Crux

Terrestrial organisms aren’t always stationary entities, they often move around the landscape searching for food, potential mates, or more ideal environments. Over time, these movements may introduce the species into new environments, as some change allows the species to expand their historical range.

An interesting aspect of this shifting of the species range is how the organisms at the edge of the distribution are maladapted to the novel environments, as most of the species will be adapted to conditions at the core of the species range. To overcome this, they must adapt to the new conditions. Successful adaptation is dependent on changes in gene frequencies away from the historical genotypes, with an increase in genes that promote survival in the new habitats. The authors in this study used molecular techniques to identify genes that new environments might select for.

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Why Defining Biodiversity Matters in an Ecosystem

Forests such as Białowieska in Poland perform a wide range of functions, but if its biodiversity rises, how will this change?

Forests such as Białowieska in Poland perform a wide range of functions, but if its biodiversity rises, how will this change? (Image Credit: Jacek Karczmarz, CC A 3.0)

Biotic homogenization can decrease landscape/scale forest multifunctionality (2016) von der Plas et al., Proceedings of the National Academy of Sciences of the United States of America, 113

The Crux

Any ecosystem performs a multitude of functions, benefiting both the species that live in it and the humans who interact with it, from litter decomposition to resistance of drought to timber production. As such, maintaining high levels of ecosystems is a well-studied concept, and it has been posited that high levels of biodiversity increase the levels functions an ecosystem can perform, or its multifunctionality.

But while the word biodiversity is recklessly bandied about these days, scientifically it’s a somewhat vague term. At an ecosystem level, you may have patches of very high local (or alpha) diversity, but the turnover of species between patches (beta diversity) might be quite low. The variation in types of biodiversity may influence your ecosystem multifunctionality. For instance, patches of high alpha diversity might lead to high levels of functionality in some patches, but little functionality elsewhere, whereas high levels of beta diversity may lead to low levels of functionality, but many functions. This paper investigates relationships between different biodiversity levels and ecosystem multifunctionality.

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