sexual jealousy

• Unlike women men cannot be sure if they truly are the biological father of offspring called paternal uncertainty
• Risk of cuckoldry which is raising a child not biologically yours
• since cuckoldry involves investment in offspring eg. time, effort and food of rivals genes, this leaves father with less resources to invest in own biological offspring
• Avoid cuckoldry more reproductively successful better survival of their genes
• psychological mechanisms have evolved in males such as sexual jealousy and possessive behaviours to help avoid cuckoldry and improve chances of passing on genes
• lead to males using aggressive strategies to retain partners and prevent them from straying/ infidelity