Genes in parallel

Adaptation from genetic variation

One of the central themes of this blog, and indeed of evolutionary biology as a whole, is the notion that adaptation is often underpinned by genes. Genetic variation acts as the basis for natural selection to favour or disfavour traits: while this is directly through phenotypic traits (e.g. fur colour, morphology, behaviour), these traits are typically determined by a genetic component. In the early stages of adaptation, evolution can often be observed by changes in the frequency of genetic variants (alleles) within a species or population over time as natural selection acts, gradually leading to the observable (and sometimes dramatic) change in species over time.

Continue reading

Changing the (water)course of history

The structure of a river system

For anyone who has had to study geography at some point in their education, you’d likely be familiar with the idea of river courses drawn on a map. They’re so important, in fact, that they are often the delimiting factor in the edges of countries, states or other political units. Water is a fundamental requirement of all forms of life and the riverways that scatter the globe underpin the maintenance, structure and accumulation of a large swathe of biodiversity.

So, what is a river?

Continue reading