K. Johannesson

The brittle star genome illuminates the genetic basis of animal appendage regeneration

This study presents a chromosome-scale genome assembly of the brittle star and identifies conserved gene expression patterns during regeneration across invertebrates and vertebrates.

Predicting rapid adaptation in time from adaptation in space: a 30-year field experiment in marine snails

The paper predicts rapid temporal adaptation in marine snails using spatial genetic and phenotypic variation from a 30-year transplant experiment, finding observed changes align with predictions.

Phenotypic divergence and genomic architecture between parallel ecotypes at two different points on the speciation continuum in a marine snail

The paper compares parallel ecotypes of Littorina saxatilis in Spain and Sweden to assess divergence in gene flow, finding stronger reproductive isolation in Spain despite similar phenotypic divergence.

Coupling of 12 chromosomal inversions maintains a strong barrier to gene flow between ecotypes

The paper identifies 12 chromosomal inversions that strongly couple reproductive barriers between ecotypes of Littorina fabalis, maintaining genetic integrity despite hybridization.

Understanding the adaptive role of chromosomal inversions across large geographical scales: The potential of pool-seq data

The paper uses pool-seq data to analyze chromosomal inversions across geographical scales, finding that some inversions contribute to local adaptation to environmental factors like wave exposure and shore height.

Selection on many loci drove the origin and spread of a key innovation

The paper investigates the genetic basis of a key innovation in Littorina snails, finding polygenic selection and gradual evolution of live-bearing traits.

Clones on the run - the genomics of a recently expanded facultative asexual species

The paper uses genome data and modeling to explain why clones dominate range margins in a recently expanded seaweed, showing they arise from sexual populations after bottlenecks and spread ahead of them.

Shallow environmental gradients can cause range margins to form

The paper shows that shallow environmental gradients can lead to sharp range margins when multiple selection gradients steepen each other, even if one gradient is shallow across the range.

A large chromosomal inversion shapes gene expression in seaweed flies (Coelopa frigida)

This study examines how the Cf-Inv(1) chromosomal inversion in seaweed flies affects gene expression across sexes and life stages, identifying candidate variants that may influence adaptive traits.

Ecological load and balancing selection in circumboreal barnacles

The paper identifies balancing selection in circumboreal barnacles, showing 4% of genes are maintained across 2 million years, with functions in ion regulation, pain reception, and heat tolerance.

Assortative mating, sexual selection and their consequences for gene flow in Littorina

This study examines size-assortative mating in Littorina saxatilis and shows it contributes to reproductive isolation but sexual selection has a stronger impact on reducing gene flow between ecotypes.

Strong spatial genetic structure in a Baltic Sea herbivore due to recent range expansion, multiple bottlenecks and low connectivity

The paper examines population genetic structure in the Baltic Sea crustacean Idotea balthica, finding strong spatial genetic patterns linked to biophysical connectivity and historical bottlenecks during range expansion.

Genomic architecture of parallel ecological divergence: beyond a single environmental contrast

This study investigates the genetic basis of parallel ecological divergence in Littorina saxatilis across two environmental axes, finding low but heterogeneous genomic sharing and complex interactions between geography, history, and environmental congruence.