Shark ecology and biodiversity during the mid-Cretaceous

Project overview

The mid Cretaceous (Albian to Cenomanian) saw dramatic environmental change. Globally, it was a period of warming and sea level rise. In northern Europe this time period marked the change from syn-rift to post rift deposition and the flooding of local land areas, associated with a change from siliciclastic to carbonate sedimentary regimes. This time period also saw the radiation of many marine clades, including the sharks and rays. This project seeks to understand the links between biodiversity and environmental change during this period.

The project would involve integrating museum collection data with bulk sampling of mid Cretaceous sites across England to collect a large data set of shark teeth. Shark diversity and autecological patterns can then be compared to other palaeoenvironmental proxies including invertebrate faunas and microbiotas (for ecosystem reconstruction), as well as stable isotope analysis (for studies of palaeo water temperature and local carbon cycle).

Preliminary sampling has indicated that shark faunas within rocks of this age are dramatically different in the Anglo-Paris Basin (APB) of SE England and the North Sea Basin (NSB) of NE England, with transitional faunas between. Macropredatory pelagic lamniform sharks were common in the APB but almost absent in the NSB, whilst smaller nektobenthic sharks dominate in the NSB. Teeth of taxa common to both are consistently smaller in the NSB. The causes of these differences are presently unknown. 

Project Specific Training

Fieldwork training and collection of field samples will be carried out as one-to-one training by the supervisors, as will training on sample processing and specimen identification and taxonomy. Fieldwork health and safety and first aid training will be carried out at Birkbeck by an external provider. Training in stable isotope analysis and electron microscopy will be carried out by lab managers at Birkbeck and the NHM.