Diatom research

Our diatom research is focused on the pursuit of comparative biology: the systematics, evolution and biogeography of freshwater diatoms.

The research covers both extinct and extant taxa, and utilises both fossil and preserved material as well as living material in the form of cultured collections.

There are some 10-12,000 known species of freshwater diatoms, with a further 200-250,000 suspected species.

A series of projects investigating their morphology, phylogenetic relationships and distribution relative to all organisms surrounding the margins of the Pacific Ocean are being carried out at the Museum.

Projects include:

Interdisciplinary research into species-rich, poorly understood taxa

This project focuses on the ‘araphid’ diatoms - numbering around 4-5,000 known species, with many more still to be described. 

Although a non-monophyletic group, it is significant because it contains species that relate to the largest two clades.

Contemporary value and relevance of historical collections

This covers studies on diatom ‘hard-parts’ - the silica valves and girdle, especially the fossil remains.

The specimen collections at the Museum are particularly important, as they represent ‘anatomical’ specimens rather than voucher material collected for another purpose. The scientific problems requiring study of this material testifies to the contemporary value and relevance of historical collections.

The origin and distribution of biodiversity

This project involves floristic and taxon-based research, focusing on key questions of the origin and distribution of biodiversity.

The biogeographic component of this project is focused upon ancient lakes, particularly Lake Baikal and Lake Ohrid. 

Lake Baikal is of significance to Pacific-margin organism distribution and therefore to understanding the opening of the Pacific - perhaps the most significant organismal biogeography problem relating to the origin of the Southern hemisphere biota.

Geographical diversity

This project focuses on the evolutionary interpretation of geographical diversity and its wider dimensions, including the global biodiversity crisis and climate change.

This work relates to the other three freshwater diatom projects, but with an added dimension.

Since benthic diatoms from ancient lakes are generally poorly understood and documented, any knowledge of these organisms at least alerts us to their abundance and uniqueness - their levels of endemicity, if not to their significance within the global biodiversity crisis and climate change.