The evolving jigsaw puzzle: origins, diversity, modifications and development of skull sutures
This project will investigate the biology of vertebrate skull sutures.
The studentship starts October 2020 and is funded by NERC.
The vertebrate skull provides protection for the brain, supports numerous cranial muscles that allow feeding and respiration and allows many other critical functions.
Such cranial skeleton of any vertebrate is a very complex three-dimensional puzzle of bones and its exact shape and composition reflect the evolutionary history of the species, reveal biomechanical properties and are heavily used for classification and taxonomic identification.
Cranial sutures separate the bones of the skull and function as sites of bone growth and stress diffusion. They are essential for proper development of individual skull bones and for their integration with each other and other cranial tissues and organs. Sutures can remain open and functional, or close leading to fusion of bordering bones.
Suture closure leads to changes in skull composition during evolution and improper suture closure during development can lead to a variety of abnormal, often severe, conditions in humans. Thus, understanding of how sutures are established, maintained and how they close is critical to addressing many of the long-standing questions on vertebrate skull evolution, development and disease.
Aims and Methods
To gain new insights into the suture biology, this PhD student will join an active effort to explore a growing database of 3D CT (computer tomography) scans of vertebrate skulls in Abzhanov and Goswami groups.
More specifically, this student will continue and complete analysis of suture types using our own comprehensive suture classification system which spans the entire diversity of vertebrates from early placoderm fishes to modern tetrapods, including material from both fossils and extant species.
Thus, the 1st aim will be to quantitatively and qualitatively measure diversity of sutures from their origins and document how they changed through the major life history transitions, such as water-to-land transition, from feeding by suction to feeding by biting and chewing (mammals) and pecking (birds), emergence of jaw modifications, such as toothless beaks.
The 2nd aim is to compare developing sutures in crocodilian, bird and turtle embryos as important case studies. These related reptilian lineages show both gross similarity of their skull composition and suture patterns but also demonstrate examples of multiple bones losses and fusions due sutural closures, e.g. premaxillary bones fusing to form a beak bone in birds and turtles, and formation of fused frontal and parietal bones to form a thick brain vault in crocodilians.
These sutures will be studied using an arsenal of histological, cell proliferation and gene expression methods to reveal the genetic causes of these transitions.
Under the 3rd aim, the discovered candidate genes and cellular processes will be validated by functional experiments on chicken and crocodilian embryos (available from breeding facilities) using relevant lab protocols.
The data from this project will help to better understand the nature of large-scale skull composition patterns in vertebrates and will provide mechanistic explanation underlying changes in modularity and integration during skull evolution.
To be eligible for a full award a student must have:
- British Citizenship or;
- Settled status in the UK, meaning they have no restrictions on how long they can stay,
- Been ‘ordinarily resident’ in the UK for 3 years prior to the start of the studentship - (For non-EU citizens, this must NOT have been in full time education.)
This means they must have been normally residing in the UK (apart from temporary or occasional absences). This does not apply to UK nationals.
For more information, download this PDF.
How to apply
Applications for this PhD are processed through Imperial College.
To apply, please send the following documents to the lead supervisor, Dr Arkhat Abzhanov:
- Curriculum vitae.
- 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.
- Names of two academic referees.
The deadline for applications is 6 January 2020.
This is a joint project between The Science and Solutions for a Changing Planet (SSCP) Doctoral Training Partnership at Imperial College London and The Natural History Museum.