Why do cuckolded males provide paternal care?

Area of Science:

• Evolutionary biology
• Behavioral ecology
• Animal reproduction

Background:

• Paternal care is widespread, but its adjustment based on paternity certainty is poorly understood.
• Males typically do not reduce investment when cuckolded, challenging evolutionary explanations for paternal care.
• Understanding the drivers of paternal care requires examining male responses to potential paternity loss.

Purpose of the Study:

• To investigate the factors influencing male decisions to adjust paternal investment when faced with cuckoldry.
• To identify the conditions under which selection favors males that reduce care upon discovering cuckoldry.
• To explain the prevalence of paternal tolerance despite potential paternity loss across diverse taxa.

Main Methods:

• Comparative analysis across major animal groups: birds, fish, mammals, and insects.
• Examination of the interplay between costs of parental care and risk of cuckoldry.
• Modeling of selection pressures on male parental investment strategies.

Main Results:

• Cuckolded males reduce paternal investment only when both the costs of care are high and the risk of cuckoldry is significant.
• In many species, these specific conditions for reducing care are not met.
• Males that tolerate cuckoldry have often outcompeted those that abandon offspring.

Conclusions:

• Selection favors reduced paternal effort in response to cuckoldry only under specific, high-cost, high-risk scenarios.
• The widespread tolerance of cuckolded males suggests that the conditions for abandoning offspring are rarely met.
• Evolutionary pressures have shaped diverse strategies for paternal care, with tolerance being a common outcome.