J. Polechova

The costs and benefits of dispersal in small populations

This study shows that dispersal benefits adaptation in small populations by reducing genetic drift, even with leptokurtic dispersal, but can hinder adaptation in steep environmental gradients.

Sympatric ecological divergence with coevolution of niche preference

This study shows that sympatric ecological divergence requires co-evolving niche preference, as disruptive selection and genetic factors can reduce polymorphism unless assortment mechanisms are in place.

The influence of fluctuating population densities on evolutionary dynamics

This study examines how fluctuating population densities affect evolutionary dynamics in spatially structured populations, showing that ecological feedback can reduce the equilibrium frequency of locally adapted types.

Is the sky the limit? On the expansion threshold of a species’ range

The paper identifies an expansion threshold for species range limits based on dispersal fitness cost and genetic drift, showing how these parameters determine range margin formation and potential extinction.