Adaptation to extreme environments: Evolution of unusual body plans in Southern Ocean Echinoids

Project overview

The deep, cold waters of the Southern Ocean are home to enigmatic, morphologically unusual radiation of sea urchins belonging to the Holasteroida.

This project aims to use a unique collection of these rare species to uncover the evolutionary history of body plans and adaptive radiations in the polar benthos. 

Project description

Understanding how animals have adapted to extreme environments is of fundamental importance for understanding the evolutionary process in a changing world.

The Holasteroida, a primarily deep-water, highly morphologically derived group of sea urchins are amongst the least understood members of the deep Southern Ocean benthos, a region in which they appear to be diverse.Although most are theorized to be epibenthic deposit feeders, little is known about their development, life history or ecology. In part, this reflects their thin and extremely fragile tests –inhabiting the seafloor below or close to the Carbonate Compensation Depth and protected from currents while submerged in soft substrata, they are often crushed during collection.

This novel, interdisciplinary project seeks to understand the ways in which Holasteroids have adapted to life in an extreme environment, to determine whether the Southern Ocean acts as a cradle for deep sea diversity and what this suggests about speciation on the bathyal and abyssal sea floor.

Using high-resolution 3D-morphometrics and a unique collection of near pristine specimens held at the Natural History Museum (NHM), the student will use phylogenetic and statistical modelling to characterize growth and development in the evolution of the Holasteroid body plan. This will be combined with phylogenetic, molecular and biogeographical data to test hypotheses around the functional ecology, evolutionary history and biogeography of the clade.

With a supervisory team spanning the NHM, University of Southampton, and British Antarctic Survey, this project will greatly improve our knowledge of the Holasteroida, and adaptive radiations in the deep sea.  

Training

Our programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted at the Natural History Museum. Specific training will include:  

• Morphological analysis using modern imaging techniques, including SEM, µ-CT and morphometrics 
• Image analyses using ORS Dragonfly, ImageJ, Checkpoint 
• Genetic techniques, e.g. DNA barcoding and genetic analysis 
• Taxonomic identification in echinoids 
• Statistical analyses 

Soft skill and outreach training will be available via the supervisors’ institutions. 

Result presentation at (inter)national conferences will be encouraged as is networking with the international research community. No fieldwork is tied to the project, but opportunities of research cruise participation may arise via supervisor contacts. 

Entry requirements

A UK bachelor’s degree with upper second-class honours or higher in a relevant subject. See international equivalent qualifications on our website. English language: IELTS 6.5 overall, with a minimum of 6.0 in all components. We accept other English language tests.

Further reading

Fabri-Ruiz, Salomé, et al. "Southern Ocean Echinoids database–An updated version of Antarctic, Sub-Antarctic and cold temperate echinoid database." ZooKeys 697 (2017): 1.

Mooi, Rich, and Bruno David. "Ontogeny and origin of the brooding system in Antarctic urechinid sea urchins (Echinodermata, Holasteroida)." Zoomorphology 113.2 (1993): 69-78.

Mongiardino Koch, Nicolás, and Jeffrey R. Thompson. "A total-evidence dated phylogeny of Echinoidea combining phylogenomic and paleontological data." Systematic Biology 70.3 (2021): 421-439.