{"id":{"repo_id":"gsu","oai_identifier":"oai:digitalcommons.georgiasouthern.edu:etd-1711"},"canonical_url":"https://search.dev.ndltd.org/etd/gsu/oai:digitalcommons.georgiasouthern.edu:etd-1711","repository":{"repo_id":"gsu","name":"Georgia Southern University","base_url":"https://digitalcommons.georgiasouthern.edu/do/oai/"},"display":{"title":"Parental Investment and Male Ornamentation in the Eastern Bluebird (Sialis Sialis)","abstract":"Bright plumage coloration in most birds is thought to be a product of sexual selection. Brighter, more-ornamented males are preferred by females because their plumage conveys information regarding the quality of the individual. One measure of male quality is willingness to invest in offspring. In birds, investment is usually measured as the rate at which nestlings are provisioned. However there are other forms of parental investment. The purpose of this study is to quantify the relationship between two measures of parental investment and their association with structural plumage coloration in male Eastern Bluebirds (Sialia sialis). I found there was no correlation between nestling provisioning and nest defense for males or females. Males with brighter UVblue plumage tend to provision nestlings at higher rates and more-ornamented males tend to defend the nest from a predator at lower rates. This study suggests that structural coloration is an indicator of the ability of a male to invest in its young. However, because nestling provisioning and nest defense (the two main male parental investments) were not correlated, I suggest that nestling provisioning and nest defense are not equivalent measures of parental investment, and condition-dependent traits have different relationships to different measures of parental investment.","abstract_html":"Bright plumage coloration in most birds is thought to be a product of sexual selection. Brighter, more-ornamented males are preferred by females because their plumage conveys information regarding the quality of the individual. One measure of male quality is willingness to invest in offspring. In birds, investment is usually measured as the rate at which nestlings are provisioned. However there are other forms of parental investment. The purpose of this study is to quantify the relationship between two measures of parental investment and their association with structural plumage coloration in male Eastern Bluebirds (Sialia sialis). I found there was no correlation between nestling provisioning and nest defense for males or females. Males with brighter UVblue plumage tend to provision nestlings at higher rates and more-ornamented males tend to defend the nest from a predator at lower rates. This study suggests that structural coloration is an indicator of the ability of a male to invest in its young. However, because nestling provisioning and nest defense (the two main male parental investments) were not correlated, I suggest that nestling provisioning and nest defense are not equivalent measures of parental investment, and condition-dependent traits have different relationships to different measures of parental investment.","abstract_has_math":false,"creators":["Wetzel, Daniel Paul"],"institution":null,"degree_name":"Master of Science in Biology (M.S.)","degree_level":"Thesis (open access)","degree_discipline":"Department of Biology","degree_department":null,"school":null,"contributors":["Steve Vives","Daniel Gleason"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2006,"date_issued":"2006-12-01T08:00:00Z","date_published":"2006-12-01T08:00:00Z","updated_at":"2026-07-24T02:27:26Z","subjects":["ETD","Parental investment","Sexual selection","Structural coloration","Nest defense","Eastern Bluebird","Sialia sialis 2","Birds"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://digitalcommons.georgiasouthern.edu/etd/711","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Steve Vives","Daniel Gleason"]},{"key":"dc:creator","label":"Author","values":["Wetzel, Daniel Paul"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2013-10-17T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Department of Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis (open access)"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science in Biology (M.S.)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["ETD","Parental investment","Sexual selection","Structural coloration","Nest defense","Eastern Bluebird","Sialia sialis 2","Birds"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://digitalcommons.georgiasouthern.edu/etd/711"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Bright plumage coloration in most birds is thought to be a product of sexual selection. Brighter, more-ornamented males are preferred by females because their plumage conveys information regarding the quality of the individual. One measure of male quality is willingness to invest in offspring. In birds, investment is usually measured as the rate at which nestlings are provisioned. However there are other forms of parental investment. The purpose of this study is to quantify the relationship between two measures of parental investment and their association with structural plumage coloration in male Eastern Bluebirds (Sialia sialis). I found there was no correlation between nestling provisioning and nest defense for males or females. Males with brighter UVblue plumage tend to provision nestlings at higher rates and more-ornamented males tend to defend the nest from a predator at lower rates. This study suggests that structural coloration is an indicator of the ability of a male to invest in its young. However, because nestling provisioning and nest defense (the two main male parental investments) were not correlated, I suggest that nestling provisioning and nest defense are not equivalent measures of parental investment, and condition-dependent traits have different relationships to different measures of parental investment."]},{"key":"dc:title","label":"Title","values":["Parental Investment and Male Ornamentation in the Eastern Bluebird (Sialis Sialis)"]}]}],"canonical_facts":{"dc:contributor":["Steve Vives","Daniel Gleason"],"dc:creator":["Wetzel, Daniel Paul"],"dc:date.available":["2013-10-17T07:00:00Z"],"dc:description.abstract":["Bright plumage coloration in most birds is thought to be a product of sexual selection. Brighter, more-ornamented males are preferred by females because their plumage conveys information regarding the quality of the individual. One measure of male quality is willingness to invest in offspring. In birds, investment is usually measured as the rate at which nestlings are provisioned. However there are other forms of parental investment. The purpose of this study is to quantify the relationship between two measures of parental investment and their association with structural plumage coloration in male Eastern Bluebirds (Sialia sialis). I found there was no correlation between nestling provisioning and nest defense for males or females. Males with brighter UVblue plumage tend to provision nestlings at higher rates and more-ornamented males tend to defend the nest from a predator at lower rates. This study suggests that structural coloration is an indicator of the ability of a male to invest in its young. However, because nestling provisioning and nest defense (the two main male parental investments) were not correlated, I suggest that nestling provisioning and nest defense are not equivalent measures of parental investment, and condition-dependent traits have different relationships to different measures of parental investment."],"dc:identifier":["https://digitalcommons.georgiasouthern.edu/etd/711"],"dc:subject":["ETD","Parental investment","Sexual selection","Structural coloration","Nest defense","Eastern Bluebird","Sialia sialis 2","Birds"],"dc:title":["Parental Investment and Male Ornamentation in the Eastern Bluebird (Sialis Sialis)"],"thesis:degree_discipline":["Department of Biology"],"thesis:degree_level":["Thesis (open access)"],"thesis:degree_name":["Master of Science in Biology (M.S.)"]},"updated_at":"2026-07-24T02:27:26Z"}