This week Adam Walton goes "behind the scenes" at the National Museum Cardiff, one of the seven institutions that make up the National Museum Wales. Away from the public display areas there is a maze of laboratories and scientific libraries housing a small army of scientists working in a wide range of subjects.

Adam chats to Graham Oliver who is Head of Department for Biodiversity and Systematic Biology and discusses the importance of mapping the bivalves in UK waters. Ingrid Juettner, who is Research Curator for Diatoms, explains these intruguing single cell creatures which can play a key role in measuring pollution and climate change. Adam gets to test his knowledge of minerals with the museum's Keeper of Geology Richard Bevins who has been making a special study of bluestones at Stonehenge, and their geological origins in Wales. The final port of call is the basement of the museum where petrologist Jana Horak shows Adam around their unique rock collection.