Topic
Natural selection research, explained
9 open-access natural selection studies, each with a flashcard deck and a quiz.
- What does Arabidopsis polymorphism look like genome-wide?
A. thaliana shows clear global population structure and isolation by distance; demography can mimic selection in standard tests.
- Hybrid necrosis as plant autoimmunity
Arabidopsis hybrid necrosis is a Dobzhansky–Muller incompatibility driven by autoimmune NB-LRR conflict.
- Can leaky vaccines favor nastier viruses?
Imperfect Marek’s disease vaccination keeps infected chickens alive longer, boosting transmission of strains too lethal to persist without vaccines.
- Why isn’t diversity proportional to population size?
Natural selection via hitchhiking and background selection constrains neutral diversity, especially in species with larger census sizes.
- How do Sinocyclocheilus genomes record cave life?
Sinocyclocheilus cavefish genomes reveal troglomorphic adaptations such as eye degeneration and albinism, paralleling and differing from Astyanax.
- Environment couples selection and heritability
In Soay sheep, strong selection on birthweight occurs when heritability is lowest, limiting evolutionary response.
- Why is CCR5-Δ32 common only in Europe?
CCR5-Δ32 likely rose under strong selection and spread fast by long-range dispersal; its range is limited more by time than by southern selection barriers.
- Can one gene affect butterfly population growth?
Allelic variation at Pgi (or tightly linked loci) predicts population growth in the Glanville fritillary metapopulation.
- Why do immune genes keep evolving across tetrapods?
Shared positive selection in birds and mammals concentrates on immune—especially antiviral—genes, implicating pathogens as a consistent selective pressure.