The impact of Anthropocene and deep-time warming on burrowing decapod crustaceans
Rising atmospheric carbon dioxide levels and global temperatures are predicted to significantly impact marine animals and ecosystems. One key prediction is that the body size of marine ectothermic animals will shrink in response to warming, altering ecosystem function.
Animals that burrow into the seafloor are particularly important to ecosystems because their bioturbation changes sediment biogeochemistry and nutrient cycling, in turn impacting productivity .
Burrowing decapods, in particular the Axiidea and Gebiidea, are amongst the most critical of these ecosystem engineers as they produce some of the deepest and most complex marine burrows.
This project will test the prediction that global warming shrinks the size of burrowing decapods and their burrows, and will reveal the consequences of these changes forecosystem function by modelling their impact on nutrient cycling, productivity and marine biodiversity.
To achieve these aims, the student will compile and analyse a range of complementary datasets of modern, historic and fossil animals and their burrows.
Specimens of animals and burrows collected from the past 200 years housed in museum collections will be analysed to quantify the pre-Anthropocene baseline, and to determine the extent to which animal size and burrow size, depth and complexity have changed during that time.
Preliminary data suggest that some species of decapod crustacean may already be undergoing significant size change.
Targeted fieldwork may be necessary to assess the most recentchanges. Implications of measured changes in animal and burrow size for ecosystem functions will be modelled to help predict future changes.
Fossil data will also be collected and analysed from targeted fieldwork to determine the extent to which size reduction has happened during past warming events, across a range of different rates and magnitudes of climate change.
Although decapod crustaceans are relatively rare in the fossil record, their burrows are very common and published studies have already demonstrated significant changes in the size and depth of these burrows during past episodes of climate change.
Moreover, CO2 levels are already at levels last recorded in the Pliocene, and with the potential threat of widespread biodiversity loss and impending mass extinction, the fossil record is becoming more relevant to studies of future change .
Moreover, the fossil record provides a unique archive of how marine ecosystems have responded to past warming, and contains the only empirical data showing how Earth’s natural ecosystems functioned at atmospheric CO2 levels and temperatures greater than the present day and at levels predicted for the end of this century.
This range of data enables the Anthropocene crisis to be placed in proper evolutionary context and for predictions of future change to be modelled by interpolation not just extrapolation.
How to apply
Apply for the project on the NHM careers website by sending your CV, covering letter outlining your interest in the PhD position, relevant skills training, experience and qualifications for the research and a statement of how this PhD project fits your career development plans. Please also include two academic references.
Apply for this project through the NHM careers website
Application deadline: Midday (12pm GMT) 7 January, 2022
Read more about the Science and Solutions for a Changing Planet Doctoral Training Partnership (SSCP DTP).
 Mora et al. (2013) Biotic and Human Vulnerability to Projected Changes in Ocean Biogeochemistry over the 21st Century. LoS Biol. 11 (10)
 Calosi et al. (2019) Marine Metazoan Modern Mass Extinction: Improving Predictions by Integrating Fossil, Modern, and Physiological Data. Ann. Rev. Mar. Sci. 11, 369-90
 Ziebis et al. (1996) Complex burrows of the mud shrimp Callianassa truncata and their geochemical impact in the sea bed. Nature, 382, 619-22