The School of Geography, Earth and Environmental Sciences organises a regular series of research seminars throughout the academic year to which everyone is welcome to attend. Speakers - both external and internal to the University - will talk on topics related to all aspects of Earth Sciences.
Today's speaker is Dr Tom Harvey from the University of Leicester.
The fossil record documents an explosive Cambrian radiation of metazoans and other organisms. In particular, Burgess Shale/Chengjiang/Sirius Passet-type Lagerstätten provide us with staggeringly detailed snapshots of the unfolding drama, via their exceptional preservation of articulated, non-biomineralising macrofossils. By definition, however, exceptional occurrences tell us little about larger-scale patterns and processes, and in any case, all taphonomic modes are biased to a greater or lesser extent. As a result, many fundamental questions remain, such as when animals first evolved, and whether Burgess Shale-type assemblages are representative of Cambrian communities more generally.
To fill some of the gaps, Tom has focused his attention on small carbonaceous fossils, or SCFs, which are a category of gently-extracted “palynomorphs” that are too large and/or delicate to be routinely recovered using conventional techniques. Although SCFs have been largely overlooked, they are proving to be widespread, and offer a rich complementary dataset for Cambrian palaeobiology. As well as extending the diversity and distribution of various non-biomineralising “Burgess Shale-type” taxa, SCFs include a variety of “small shellies” preserved as carbonaceous taphomorphs, and also “cryptic” forms that have not previously been documented from the Cambrian, including derived crustaceans and meiofaunal loriciferans.
In this talk Tom will review some of the key discoveries from his recent work on SCFs from western Canada and the Baltic Basin.