Flexible courtship strategies in the fiddler crab Afruca tangeri.

Additional Supervisors

Dr Safi K. Darden, Centre for Research in Animal Behaviour (CRAB), University of Exeter

Dr Martin J. How, School of Biological Sciences, University of Bristol

Dr Shaun S. Killen, Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow

Location: University of Exeter, Streatham Campus, Exeter EX4 4QJ

This project is one of a number that are in competition for funding from the NERC Great Western Four+ Doctoral Training Partnership (GW4+ DTP). The GW4+ DTP consists of the Great Western Four alliance of the University of Bath, University of Bristol, Cardiff University and the University of Exeter plus five Research Organisation partners: British Antarctic Survey, British Geological Survey, Centre for Ecology and Hydrology, the Natural History Museum and Plymouth Marine Laboratory. The partnership aims to provide a broad training in earth and environmental sciences, designed to train tomorrow’s leaders in earth and environmental science.
For further details about the programme please see http://nercgw4plus.ac.uk/

Project details

Sexual selection—Darwin’s second great theory of evolution—explains why many animals possess elaborate courtship displays that attract potential mates, despite harming their survival. Most research has focused on morphological display traits (e.g. elongated appendages, bright colour patches), but we know relatively little about the striking behavioural displays performed in many taxa. For example, male fiddler crabs have a massively enlarged claw which they wave in the air and drum against their body and the substrate to tempt females into their burrow. This is a highly dynamic display that can be rapidly adjusted depending on the male’s energy levels, the degree of interest from passing females, the intensity of competition from rival males and the current predation risk. In this PhD project you will combine evolutionary modelling with field experiments on a wild population of fiddler crabs in the Algarve, to determine how males adaptively adjust their courtship in a dynamically changing social environment.

Project Aims and Methods

The overall goal is to predict how males should flexibly adjust their courtship behaviour to maximise their reproductive success, and test these predictions in a wild population of fiddler crabs. There are multiple directions the work could take and we are particularly interested to hear from students who want to play an active role in designing the project. Possible research questions include:
• How do males adaptively allocate their courtship effort across the tidal cycle?
• What are the physiological consequences of courtship and how do males balance the costs and benefits across multiple mating opportunities?
• How is dynamic courtship behaviour mechanistically linked to morphological traits (e.g. claw size) and aspects of male quality?
• How do males combine waving and drumming displays to attract females efficiently?
The project will integrate theoretical and empirical approaches to answer these questions. Computer models of state-dependent behaviour will be developed to identify evolutionarily stable strategies for male courtship. The predictions from these models will be tested in fiddler crabs at our established field site in the Ria Formosa Natural Park in the Algarve, Portugal, using behavioural observations combined with physiological assays, audio-visual recordings and experimental manipulation of courtship traits and the social environment.

Training

The student will receive expert training from the supervisory team in evolutionary modelling, behavioural experiments and physiological measurements. S/he will spend 2–3 months each year in the Ria Formosa Natural Park to conduct fieldwork, supported by the Portuguese conservation ministry (ICNF). S/he will be embedded in Exeter’s Centre for Research in Animal Behaviour (CRAB), a vibrant research environment with regular seminars, workshops and opportunities for collaboration. There will also be opportunities to spend time in the sensory and physiological labs of co-supervisors Dr How and Dr Killen and to attend the international postgraduate course in Sensory Ecology at Lund University. The student will be encouraged to present their findings at scientific conferences and participate in public outreach activities, both in Portugal and the UK.