Submission Type
Poster
Abstract
Some animals form socially monogamous pair bonds in which a male and female mate and raise young together. However, individuals within a socially monogamous pair bond may still mate with other individuals; this mating is defined as extra-pair mating (EPM). Extra-pair paternity (EPP) occurs when offspring arise from EPM. In wild birds, EPM is approximated by EPP. Males benefit from EPP by siring additional offspring without any investment aside from sperm, but the benefits of EPM for females are less clear. Females may gain fertility assurance, access to better foraging grounds, and nest protection from males, as males are incentivized to defend nests that may contain their young. There are also potential costs to EPM for females, including a decrease in paternal effort by their social mates if they suspect paternity threats. I will investigate how male provisioning and nest defense are affected by EPP. I will study these questions in a well-established house wren system. I will record provisioning behaviors with cameras and then determine paternity using genetic markers. Individuals will be visually identified by the colored bands on their legs. I will test if males with more extra-pair young in their nests reduced provisioning rates. I will also test if males are more likely to help defend a neighbor’s nest against a great-horned owl model if they had sired offspring in that nest. Taken together, my research seeks to understand how EPP may benefit or cost females and how it changes male behavior.
Included in
Effects of extra-pair paternity on provisioning effort and nest defense in male house wrens (Troglodytes aedon)
Some animals form socially monogamous pair bonds in which a male and female mate and raise young together. However, individuals within a socially monogamous pair bond may still mate with other individuals; this mating is defined as extra-pair mating (EPM). Extra-pair paternity (EPP) occurs when offspring arise from EPM. In wild birds, EPM is approximated by EPP. Males benefit from EPP by siring additional offspring without any investment aside from sperm, but the benefits of EPM for females are less clear. Females may gain fertility assurance, access to better foraging grounds, and nest protection from males, as males are incentivized to defend nests that may contain their young. There are also potential costs to EPM for females, including a decrease in paternal effort by their social mates if they suspect paternity threats. I will investigate how male provisioning and nest defense are affected by EPP. I will study these questions in a well-established house wren system. I will record provisioning behaviors with cameras and then determine paternity using genetic markers. Individuals will be visually identified by the colored bands on their legs. I will test if males with more extra-pair young in their nests reduced provisioning rates. I will also test if males are more likely to help defend a neighbor’s nest against a great-horned owl model if they had sired offspring in that nest. Taken together, my research seeks to understand how EPP may benefit or cost females and how it changes male behavior.
Comments
Scott K. Sakaluk (Illinois State University)
Charles F. Thompson (Illinois State University)
Pirmin Nietlisbach (Illinois State University)