Dinosaur fossils have taught us a great deal about the mighty creatures that stalked the land more than 65 million years ago, but what about the tiny soft-bodied animals that lived under their feet? And what of the animals that predated the dinosaurs, living hundreds of millions of years before them?
The fossil precursors of insects, snails and slugs might not be as glamorous as the dinosaurs, but understanding them is just as important, because it fills in the evolutionary picture of some of the earliest creatures that lived on earth. Studying them is a challenge, but a challenge that has been met by the winner of this year's RDS/Irish Times Boyle Medal for scientific excellence, Derek Briggs.
Briggs is professor of palaeontology at the University of Bristol and, currently, a visiting professor at the University of Chicago's department of geophysical sciences. He is there with his wife, Jennifer, while their three sons study science at university in the UK.
Born in Dublin, Briggs was judged by an independent panel of international peers as having made an outstanding contribution to the development of his scientific discipline.
His discoveries, which began while he was a researcher at the University of Cambridge, working on fossil remains laid down about 505 million years ago, and his ongoing work on numerous projects, including the natural chemistry of how fossils are preserved, have captured for him the distinction of winning the RDS/Irish Times Boyle Medal.
"I am thrilled to bits, enormously excited," he says. "In a funny kind of way, I am very pleased for my parents, too." His mother and father, both of whom are enjoying good health, helped to set him on the path that led to a career in the sciences.
"My parents were always interested in natural history. They cultivated an interest from an early age," he says. He signed on for the four-year programme in natural sciences at Trinity College, Dublin, where he "got hooked" on geology and palaeontology.
He studied under Professor Charles Holland, who, at 78, has just edited The Geology Of Ireland, as reported on these pages last month. "He certainly was an inspiration," says Briggs. He also worked under Prof George Sevastopulo, who continues to teach palaeontology at Trinity. "It was a great, friendly, small department and an exciting place to be."
Things quickly became even more exciting after he began a PhD at Cambridge, where work was getting under way on the Burgess Shale fossils. The otherwise uninteresting-looking shale recovered from British Columbia, in Canada, contained a wealth of fossils dating from the Cambrian explosion, a time over 500 million years ago when the variety of life forms on earth multiplied rapidly and "virtually all of the major groups that are seen today began to emerge", says Briggs.
"There were huge collections of this material collected in the early 1900s. It transformed people's idea of that Cambrian event. We showed there were extraordinary animals which don't have modern counterparts, as well as others which are clearly the forerunners of the modern groups."
The work was not easy. The team would split open shale pieces in their search for ancient animals that in life were no more than a few centimetres long. The animals would appear in just two dimensions on the surface of the shale but, because they were so plentiful and fell to the bottom of watercourses to be fossilised in a range of orientations, the researchers at Cambridge were able to build three-dimensional images of the creatures. "You work with a microscope to understand the details."
There were numerous forms on display, including soft-bodied sponges and worms and very early arthropods - evolutionary precursors of the insects, crustaceans and spiders we see today. Modern arthropods make up about 80 per cent of all known species and also dominated in the Cambrian. "They are the most successful group on earth," he says. For this reason it is valuable to learn the evolutionary pathway to them from the Cambrian.
Briggs is now involved in a range of projects at the University of Bristol. He works with a group that is looking at fossilised soft-bodied animals discovered in a quarry in Herefordshire and dating back 430 million years, to the Silurian period.
These creatures are only a few millimetres long but, astoundingly, are preserved in three dimensions. They were discovered in nodules, or hard circular lumps, of volcanic ash; the team grind away layer after layer of ash and animal to reveal their outline. By removing just 30 thousandths of a millimetre at a time, they can define and study the animal's shape on a computer.
Briggs is also looking at the chemistry of fossilisation. Unusual chemical processes take place, he says, starting within days or weeks of death. The team has shown in laboratory experiments how the fossils can be preserved in very fine detail in certain chemical environments, even though the animals are millions of years old.
This information can be enormously helpful to fossil hunters, particularly those looking for the earliest small soft-bodied animals. It identifies the geological deposits most likely to yield recoverable fossils.
Congratulations to Prof Briggs, the Boyle laureate for 2001. He will be flown to Dublin for the presentation ceremony early in the new year.