What kinds of organisms lived on New Zealand's rocks around 48 million years ago?

That was the focus of research by Victoria University PhD graduate Dr Chris Clowes.

"I was interested in looking at microscopic fossil algae called dinoflagellates that were found fossilised in New Zealand rocks dating from the Eocene period, which occurred between 48 and 34 million years ago," says Dr Clowes.

As part of his PhD research, he focused specifically on the dinoflagellates themselves as biological entities and their relationship to one another.

A total of 80 rock samples were provided by Geological and Nuclear Sciences which were sourced from a number of localities around New Zealand. They are believed to be between 48 and 34 million years old.

"I harvested extensive single mount collections from a number of samples that were found to be particularly rich, well preserved or contained new organisms. This involved looking down a microscope and picking a dinoflagellate, about a twentieth of a millimetre long, out of a mass of organic material on the point of a needle. In the end, I picked out more than a thousand of them, and chose the best to illustrate the species I was working with."

Dr Clowes says his research identified 25 new species of these organisms. Most previous research in New Zealand has focused on older rocks, so he wasn't surprised to find many that were new.

He says his research could have implications for dating rocks, with a wide range of applications including, topically, the search for new petroleum reserves.

Dr Clowes graduated with a PhD in Geology and currently works as a management consultant. He was supported by funding from Victoria University and his supervisor was Associate Professor Michael Hannah.