Details of Award
NERC Reference : NE/D000394/1
Quantifying the benefits of helping to increase group size in an avian cooperative breeder
Grant Award
- Principal Investigator:
- Professor AF Russell, University of Sheffield, Animal and Plant Sciences
- Grant held at:
- University of Sheffield, Animal and Plant Sciences
- Science Area:
- Terrestrial
- Overall Classification:
- Terrestrial
- ENRIs:
- Biodiversity
- Science Topics:
- Population Genetics/Evolution
- Conservation Ecology
- Population Ecology
- Behavioural Ecology
- Abstract:
- Many animals live and breed for much of their lives in groups. However, in some group living species, called cooperative breeders, group members do not breed and instead help to rear the offspring of other group members. Cooperative breeding systems are most commonly found in insects (like ants, wasps and bees), birds (particularly those in Australia) and mammals (like lions, wolves and meerkats). Cooperative breeding is also common in humans; offspring may stay at home and help their mother and father rear more brothers and sisters, while grandmothers may help their own offspring to produce more grand-offspring. The question is why do such individuals help instead of breed? Put more scientifically, if the behaviour of individuals is governed by their genes and genes are past on from one generation to the next by producing offspring, how can genes for cooperation occur in a population? One explanation is that individuals pass on genes indirectly through helping relatives (which share many of their genes). That most helpers do care for the offspring of relatives seems to support this idea. An alternative, however, is that in species where increases in group size are associated with increases in survival and breeding probability in the future, individuals may help in order to increase the size of their group. In this case, helping relatives is not the cause of the cooperative behaviour, but is a consequence of the benefits of staying at home (where relatives often are) and helping to increase group size. Testing which of these two alternatives is correct has proved difficult but is central to our understanding of group living and cooperation in both animals and in humans. The aim of this study is to use a novel approach to understand the evolution of cooperative breeding in vertebrates. The animal that I will use for my study is the chestnut-crowned babbler, a highly cooperative bird living in groups of up to 20 in the arid regions of eastern Australia. Instead of watching these birds for many years and trying to work out whether individuals that help, pass more genes to the following generation by helping relatives or not, I will use measures of energetic expenditure to calculate the costs and benefits of group living and cooperation. Energy expenditure is likely to correlate both with survival and breeding success: if individuals lose too much energy they will die or find breeding difficult. Specifically, I will: (1) determine what the energetic benefits are of living in a large group; and (2) determine what the energetic costs are of helping to raise the size of the group in the first place. If the benefits are less than the costs then for cooperative breeding to evolve, individuals must help relatives. If the benefits are greater than the costs, then cooperative breeding can evolve between non-relatives. In addition, I will identify the energetic benefit that individuals gain from group living. Helpers may benefit by increasing group size in two ways. First, being in a large group may allow individuals to find food more efficiently, allowing them to spend more time conserving energy and resting. Second, by huddling together to stay warm at night, when the temperature may go below 0?C, individuals may be able to conserve energy through reducing heat loss. The results from this study will not only help us to understand the evolution of cooperative breeding and group living, but will identify the way in which individuals benefit energetically, from living in a large group. The answers to the questions proposed may help to explain the importance of the family to the evolution of cooperative breeding in humans.
- NERC Reference:
- NE/D000394/1
- Grant Stage:
- Completed
- Scheme:
- New Investigators Pre FEC
- Grant Status:
- Closed
- Programme:
- New Investigators
This grant award has a total value of £50,027
FDAB - Financial Details (Award breakdown by headings)
| Total - Staff | Total - T&S | Total - Other Costs | Total - Indirect Costs |
|---|---|---|---|
| £12,051 | £2,560 | £29,874 | £5,543 |
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