Applicant: Andrew Young Funding Scheme: NERC
Background:
Seeking to explain the evolution of cooperative behaviours, such as helping to provision the offspring of others, is a key focus of behavioural ecological research and demands an understanding of the costs that helping entails and the benefits enjoyed by recipients1. It is now clear that helpers can suffer survival costs and that their recipients often experience survival and fecundity advantages1,2. However, the mechanisms underlying such effects are poorly understood. One key possibility is that helping, and being helped, alter the oxidative balance of individuals. Reactive oxygen species (ROS), which are primarily produced as a bi-product of aerobic metabolism, can cause serious damage to biomolecules. Under normal circumstances ROS are controlled by the body’s antioxidant defences, but activities that incur increased ROS production, such as hard physical work, risk overwhelming these defences. Such oxidative stress is believed to be an important mechanism underlying impaired reproductive performance and ageing3.
Remarkably, the role that oxidative balance has played in the evolution of cooperative societies has yet to be investigated. Helping to provision offspring is hard work2, and may therefore result in oxidative stress. Helping also commonly lightens the workloads of parents2, however, and so may reduce parental oxidative burdens and allow them to transfer this benefit to the production of new offspring. This ‘oxidative loadlightening’ could therefore constitute a general mechanism promoting the evolution of animal cooperation.
Aims:
I propose the first investigation of how oxidative balance may mediate the costs and benefits of cooperative behaviour. Using my existing study population of 30 cooperative groups of sparrow weavers, Plocepasser mahali, and three biochemical assays already established at Tremough, the project will test:
(1) The effects of offspring provisioning rates on oxidative balance both in parents and helpers. Brood size manipulations will be used to experimentally increase and decrease the workload faced by family groups, allowing us to relate variation in provisioning rates to blood markers of oxidative damage (malondialdehyde) and key measures of antioxidant activity, including enzymatic (superoxide dismutase) and non-enzymatic constituents (‘Total Antioxidant Capacity’ assay4).
(2) To what extent do helper contributions improve the oxidative balance of parents? To test for effects of helping on the oxidative balance of parents (assays as above), independently of the total workload of the group, we will experimentally reduce helper contributions using tail-weights5.
(3) Do load-lightened mothers produce new offspring with reduced oxidative burdens? Birds can influence the oxidative balance of their offspring by altering the levels of antioxidants deposited into egg yolk6. We will test whether recipients of help (mothers) produce more antioxidant-rich eggs, and the consequences of this for the oxidative balance, growth and survival of chicks (assays as above).
Sparrow weavers are ideal subjects as helpers lighten parental workloads7 and my own work has
proven the feasibility of all necessary field techniques (e.g. blood sampling and brood size manipulations).
Programme of work:
Year 1: fieldwork in Tswalu Kalahari Reserve, South Africa (run aim 1 experiment and collect data for aim 3); lab and data analysis at Tremough. Year 2: fieldwork (run aim 2 experiment and
collect data for aim 3); lab and data analysis at Tremough. Year 3: finish lab and data analyses and write up.
Strategic relevance:
The project falls squarely within the NERC’s remit, addressing both the behavioural ecology and environmental physiology key science topics, and, by seeking new links between cooperation, workloads and aging in a charismatic social species, is likely to attract a high quality student and generate topical and newsworthy findings (my own research on cooperative societies has already attracted media coverage in 15 countries). The project will also foster new collaborative links between myself and Dr Jon Blount (see below), dovetail synergistically with my existing NERC funded research on the hormonal regulation of vertebrate cooperation, and provide valuable data to strengthen future research council grants.
A NERC studentship would also facilitate the development of my own research group, and would be timely as I currently hold a NERC Research Fellowship and have yet to take on a PhD student within the School.
Student Support:
The student will receive strong inter-disciplinary training, covering field behavioural and
physiological techniques, experimental design, biochemical analysis, data analysis and paper writing. Dr Jon Blount will co-supervise to provide lab assay training and to guarantee supervisory support beyond the tenure of my fellowship. Field and lab costs will be met from the NERC studentship fieldwork, exceptional consumables and RTSG funds, and any shortfall will be met from my existing fellowship support.
[1] Clutton-Brock (2002) Science 296, 69-72 [2] Heinsohn (2004) Cooperative Breeding in Birds pp. 67-80 [3] Beckman & Ames (1998) Physiol. Rev. 78, 547 [4] Wood et al (2006) J. Sci. Food Agric. 86, 2057 [5] Wright & Cuthill (1989) Behav. Ecol. Sociobiol. 25, 171-181 [6] Blount et al (2004) Proc. Roy. Soc. B. 271, S79-81 [7] Lewis (1981) Behav. Ecol. Sociobiol. 9, 83-93.
Application details
You should have (or expect to gain) a 1st class or high 2:1 class degree and excellent academic references. Applications only accepted from UK/EU nationals. UK citizens and EU nationals who have been resident in the UK for 3 years prior to the start of the studentship will receive both fees and stipend scholarship, other EU nationals will receive a fees scholarship only.
Applicants should send a covering letter explaining your suitability for this post, along with a CV including contact details of two academic referees to:
Mrs S. Mudge,
Postgraduate Secretary,
School of Biosciences,
University of Exeter,
Geoffrey Pope Building,
Stocker Road,
Exeter EX4 4QD
or by email to BS-PGadmissions@exeter.ac.uk
The closing date for applications is 28th November 2008. We aim to interview short‐listed candidates in the week commencing 12th January 2009
Background:
Seeking to explain the evolution of cooperative behaviours, such as helping to provision the offspring of others, is a key focus of behavioural ecological research and demands an understanding of the costs that helping entails and the benefits enjoyed by recipients1. It is now clear that helpers can suffer survival costs and that their recipients often experience survival and fecundity advantages1,2. However, the mechanisms underlying such effects are poorly understood. One key possibility is that helping, and being helped, alter the oxidative balance of individuals. Reactive oxygen species (ROS), which are primarily produced as a bi-product of aerobic metabolism, can cause serious damage to biomolecules. Under normal circumstances ROS are controlled by the body’s antioxidant defences, but activities that incur increased ROS production, such as hard physical work, risk overwhelming these defences. Such oxidative stress is believed to be an important mechanism underlying impaired reproductive performance and ageing3.
Remarkably, the role that oxidative balance has played in the evolution of cooperative societies has yet to be investigated. Helping to provision offspring is hard work2, and may therefore result in oxidative stress. Helping also commonly lightens the workloads of parents2, however, and so may reduce parental oxidative burdens and allow them to transfer this benefit to the production of new offspring. This ‘oxidative loadlightening’ could therefore constitute a general mechanism promoting the evolution of animal cooperation.
Aims:
I propose the first investigation of how oxidative balance may mediate the costs and benefits of cooperative behaviour. Using my existing study population of 30 cooperative groups of sparrow weavers, Plocepasser mahali, and three biochemical assays already established at Tremough, the project will test:
(1) The effects of offspring provisioning rates on oxidative balance both in parents and helpers. Brood size manipulations will be used to experimentally increase and decrease the workload faced by family groups, allowing us to relate variation in provisioning rates to blood markers of oxidative damage (malondialdehyde) and key measures of antioxidant activity, including enzymatic (superoxide dismutase) and non-enzymatic constituents (‘Total Antioxidant Capacity’ assay4).
(2) To what extent do helper contributions improve the oxidative balance of parents? To test for effects of helping on the oxidative balance of parents (assays as above), independently of the total workload of the group, we will experimentally reduce helper contributions using tail-weights5.
(3) Do load-lightened mothers produce new offspring with reduced oxidative burdens? Birds can influence the oxidative balance of their offspring by altering the levels of antioxidants deposited into egg yolk6. We will test whether recipients of help (mothers) produce more antioxidant-rich eggs, and the consequences of this for the oxidative balance, growth and survival of chicks (assays as above).
Sparrow weavers are ideal subjects as helpers lighten parental workloads7 and my own work has
proven the feasibility of all necessary field techniques (e.g. blood sampling and brood size manipulations).
Programme of work:
Year 1: fieldwork in Tswalu Kalahari Reserve, South Africa (run aim 1 experiment and collect data for aim 3); lab and data analysis at Tremough. Year 2: fieldwork (run aim 2 experiment and
collect data for aim 3); lab and data analysis at Tremough. Year 3: finish lab and data analyses and write up.
Strategic relevance:
The project falls squarely within the NERC’s remit, addressing both the behavioural ecology and environmental physiology key science topics, and, by seeking new links between cooperation, workloads and aging in a charismatic social species, is likely to attract a high quality student and generate topical and newsworthy findings (my own research on cooperative societies has already attracted media coverage in 15 countries). The project will also foster new collaborative links between myself and Dr Jon Blount (see below), dovetail synergistically with my existing NERC funded research on the hormonal regulation of vertebrate cooperation, and provide valuable data to strengthen future research council grants.
A NERC studentship would also facilitate the development of my own research group, and would be timely as I currently hold a NERC Research Fellowship and have yet to take on a PhD student within the School.
Student Support:
The student will receive strong inter-disciplinary training, covering field behavioural and
physiological techniques, experimental design, biochemical analysis, data analysis and paper writing. Dr Jon Blount will co-supervise to provide lab assay training and to guarantee supervisory support beyond the tenure of my fellowship. Field and lab costs will be met from the NERC studentship fieldwork, exceptional consumables and RTSG funds, and any shortfall will be met from my existing fellowship support.
[1] Clutton-Brock (2002) Science 296, 69-72 [2] Heinsohn (2004) Cooperative Breeding in Birds pp. 67-80 [3] Beckman & Ames (1998) Physiol. Rev. 78, 547 [4] Wood et al (2006) J. Sci. Food Agric. 86, 2057 [5] Wright & Cuthill (1989) Behav. Ecol. Sociobiol. 25, 171-181 [6] Blount et al (2004) Proc. Roy. Soc. B. 271, S79-81 [7] Lewis (1981) Behav. Ecol. Sociobiol. 9, 83-93.
Application details
You should have (or expect to gain) a 1st class or high 2:1 class degree and excellent academic references. Applications only accepted from UK/EU nationals. UK citizens and EU nationals who have been resident in the UK for 3 years prior to the start of the studentship will receive both fees and stipend scholarship, other EU nationals will receive a fees scholarship only.
Applicants should send a covering letter explaining your suitability for this post, along with a CV including contact details of two academic referees to:
Mrs S. Mudge,
Postgraduate Secretary,
School of Biosciences,
University of Exeter,
Geoffrey Pope Building,
Stocker Road,
Exeter EX4 4QD
or by email to BS-PGadmissions@exeter.ac.uk
The closing date for applications is 28th November 2008. We aim to interview short‐listed candidates in the week commencing 12th January 2009