Last updated: 29 November 2011
This week Adam's fossil-hunting. In an Anglesey quarry he encounters the oldest fossils in the UK and in Cardiff he meets a rare specimen of the missing link between dinosaurs and birds.
Broadcast Tuesday 29th November at 7pm
Adam's guide is Dr. Margaret Wood, Director of GeoMôn, the Anglesey GeoPark. They begin their fossil-hunting at Gadlys Quarry in the north of Anglesey where, in 1972, Margaret discovered the oldest fossils in the UK - stromatolites dating back 860 million years. You can still find living stromatolites today in shallow tropical seas. They're created by cyanobacteria (blue-green algae) which lay down layers of sediment into hard structures which look a bit like mushrooms. In the early history of the planet these cyanobacteria generated the oxygen on which all other life on Earth depends.
The fossil hunters' next stop is Traeth Bychan, a beach on the eastern side of Anglesey. Here Margaret introduces Adam to 300 million year-old coral from the lower carboniferous period when parts of what's now Wales were at the bottom of tropical seas. It takes a few minutes for him to get his eye in but Adam soon discovers fossil coral and brachiopods in the limestone boulders scattered all over the beach.
He also gets advice from Margaret about how to achieve geological immortality and get himself fossilised. Her advice is to be buried in clay at the bottom of a river or on the sea bed where sediments are laid down!
In this week's programme we also visit the National Museum in Cardiff for a close encounter with 'The Phantom'. The Museum's Head of Paleontology, Dr. Caroline Buttler, explains to Adam that this is one of only a handful of fossils of Archaeopteryx, a feathered, flying dinosaur about the size of a magpie that's a 'missing link' between dinosaurs and birds. It's the first time that the specimen has been on public display outside Germany, where it was first discovered.
Meanwhile, Science Cafe producer Jeremy Grange nips behind the scenes to meet fossil curator Dr. Lucy McCobb and take a look at the Museum's collection of trilobites. Trilobites are an extinct class of arthropods - related to insects and crustaceans - which lived in the sea but disappeared from the fossil record 250 million years ago. The very first fossil trilobite to be recorded was in Wales in the late seventeenth century - but at the time it was mistaken for a flatfish!
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