Opposite responses to selection and where to find them

Area of Science:

• Evolutionary biology
• Quantitative genetics
• Behavioral ecology

Background:

• Traits are typically expected to evolve in the direction of selection.
• However, observed traits in organisms and breeding experiments sometimes show no or negative responses to selection.
• These phenomena are collectively termed 'opposite responses to selection'.

Purpose of the Study:

• To formalize and explain the conditions under which opposite responses to selection occur.
• To provide a unified framework linking various evolutionary phenomena.

Main Methods:

• Utilized quantitative genetic models to analyze the response to selection.
• Investigated scenarios involving direct selection and social selection.
• Examined the role of relatedness in social interactions and genetic covariance.

Main Results:

• Opposite responses to selection are expected when social selection opposes direct selection.
• These responses are also likely when individuals interact with less related conspecifics.
• A negative genetic covariance between direct and indirect fitness effects promotes opposite responses.

Conclusions:

• The study outlines specific conditions favoring opposite responses to selection in natural populations.
• It highlights the significant role of social interactions and genetic correlations in shaping evolution.
• This framework integrates diverse evolutionary observations under a single theoretical umbrella.