Saturday, February 25, 2017

Tipping points in the dynamics of speciation

Hej everyone,

sorry for the late announcement, but here it comes. Let's discuss the perspective
'Tipping points in the dynamics of speciation'
in our next EXEB meeting!

As usually, Tuesday 10 am in Darwin, fika included.


Figure 1 from the paper
Patrik Nosil, Jeffrey L. Feder, Samuel M. Flaxman & Zachariah Gompert
Nature Ecology & Evolution

Speciation can be gradual or sudden and involve few or many genetic changes. Inferring the processes generating such patternsis difficult, and may require consideration of emergent and non-linear properties of speciation, such as when small changes at tipping points have large effects on differentiation. Tipping points involve positive feedback and indirect selection stemming from
associations between genomic regions, bi-stability due to effects of initial conditions and evolutionary history, and dependence on modularity of system components. These features are associated with sudden ‘regime shifts’ in other cellular, ecological, and societal systems. Thus, tools used to understand other complex systems could be fruitfully applied in speciation research.

Thursday, February 9, 2017

On latent traits

For next week’s EXEB meeting we would like to discuss a paper on latent (‘White-Knight’) traits recently published in Trends in Ecology & Evolution. Latent traits are nonadaptiveOb where they originate but can become adaptive in new environments. Wherever these traits are plentiful, ecology rather than genetics might determine how fast new adaptations originate.

Fika will be provided

When: Tuesday, February 14, at 10.00

-Alexander

Title: The White-Knight Hypothesis, or Does the Environment Limit Innovations?



Abstract: Organisms often harbor latent traits that are byproducts of other adaptations. Such latent traits are not themselves adaptive but can become adaptive in the right environment. Here I discuss several examples of such traits. Their abundance suggests that environmental change rather than new mutations might often limit the origin of evolutionary adaptations and innovations. This is important, because environments can change much faster than new mutations arise. I introduce a conceptual model that distinguishes between mutation-limited and environment-limited trait origins and suggest how experiments could help discriminate between them. Wherever latent traits are plentiful, ecology rather than genetics might determine how fast new adaptations originate and thus how fast adaptive Darwinian evolution proceeds.