Short- and long-term antagonistic selection explains dispersal polymorphism in the common lizard

Area of Science:

• Evolutionary Biology
• Quantitative Genetics
• Population Ecology

Background:

• Dispersal is crucial for population dynamics and genetic structure.
• The persistence of dispersal polymorphism is not fully understood.
• Short-term fitness may not reflect long-term evolutionary success.

Purpose of the Study:

• To investigate the heritability and selection pressures on dispersal in common lizards (Zootoca vivipara).
• To understand the mechanisms maintaining dispersal polymorphism over time.
• To assess the role of multi-generational fitness in evolutionary equilibrium.

Main Methods:

• Utilized 20-year population monitoring data of common lizards.
• Applied quantitative genetics to estimate heritability of dispersal.
• Analyzed intragenerational and multi-generational selection on dispersal traits.

Main Results:

• Natal and adult dispersal showed weak to moderate heritability (h2=0.1-0.22).
• Natal dispersal faced antagonistic selection: reduced individual lifetime fitness but increased lineage persistence.
• Lineage persistence was linked to kin selection and neutral equilibrium.

Conclusions:

• Antagonistic selection across different timescales explains the maintenance of dispersal polymorphism.
• Multi-generational fitness metrics are essential for understanding evolutionary equilibrium.
• Focusing solely on short-term fitness can obscure the persistence of phenotypic variation.