Ecological and molecular basis of differential resource use in populations of burying beetles Nicrophorus vespilloides
type: CreativeWork
description: A fundamental prediction of ecological theory is that competition for resources can drive the evolution of specialised resource use. One way in which costly competition can be avoided is via individual specialisation, i.e., the persistence of specialised individuals within a generalist population that utilise a smaller subset of the entire population’s resource base. This could occur through the evolution of genetic morphs that specialise on different resources. Although correlational evidence exists that is consistent with this prediction, there is surprisingly little evidence that competition causes resource specialisation. Burying beetles are an ideal species for testing this prediction. They require the carcass of a small vertebrate such as a mouse or a songbird for reproduction, but carcasses can be unpredictably distributed and competition to secure ownership is correspondingly intense. For my PhD project in Prof. Rebecca Kilner’s lab, I tested whether this fierce competition for a carcass breeding resource has driven the evolution of beetles that specialise in breeding on dead mammals or dead birds. With field experiments at three different woodlands, I tested for evidence of a bias in the type of carcass favoured by Nicrophorus vespilloides and if this bias changed across the burying beetle season (from April to October each year). I found spatial and seasonal variation within each of the three populations in the preference for dead mice over dead birds. In two populations, beetles were more likely to be trapped upon dead mice overall, but were occasionally trapped with greater frequencies on dead birds. This trend was completely reversed for the third population, where beetles were more likely to be found in traps baited with dead birds than dead mice. The patterns of resource use I observed in the field could be due to adaptive partitioning of resource type within populations. To test this hypothesis, I measured the reproductive success of wild beetles ind…
abstract: A fundamental prediction of ecological theory is that competition for resources can drive the evolution of specialised resource use. One way in which costly competition can be avoided is via individual specialisation, i.e., the persistence of specialised individuals within a generalist population that utilise a smaller subset of the entire population’s resource base. This could occur through the evolution of genetic morphs that specialise on different resources. Although correlational evidence exists that is consistent with this prediction, there is surprisingly little evidence that competition causes resource specialisation. Burying beetles are an ideal species for testing this prediction. They require the carcass of a small vertebrate such as a mouse or a songbird for reproduction, but carcasses can be unpredictably distributed and competition to secure ownership is correspondingly intense. For my PhD project in Prof. Rebecca Kilner’s lab, I tested whether this fierce competition for a carcass breeding resource has driven the evolution of beetles that specialise in breeding on dead mammals or dead birds. With field experiments at three different woodlands, I tested for evidence of a bias in the type of carcass favoured by Nicrophorus vespilloides and if this bias changed across the burying beetle season (from April to October each year). I found spatial and seasonal variation within each of the three populations in the preference for dead mice over dead birds. In two populations, beetles were more likely to be trapped upon dead mice overall, but were occasionally trapped with greater frequencies on dead birds. This trend was completely reversed for the third population, where beetles were more likely to be found in traps baited with dead birds than dead mice. The patterns of resource use I observed in the field could be due to adaptive partitioning of resource type within populations. To test this hypothesis, I measured the reproductive success of wild beetles ind…
author: Issar, Swastika
language: eng
keywords: ecology, evolutionary biology, animal behaviour, resource use, burying beetles
license: https://creativecommons.org/licenses/by/4.0/
date published: 2021-01-29
date modified: 2026-07-22T22:24:13Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.78866