Speleology by a large number of human activities. Dam construction, limestone quarrying, water pollution and logging are just some of the disasters that can devastate or destroy underground biological communities. Speleologists also work with archaeologists in studying underground ruins, tunnels, sewers and aqueducts, such as the various inlets and outlets of the Cloaca Maxima in Rome. Speleology Speleology is the scientific study of caves and other karst features, their make-up, structure, physical properties, history, life forms, and the processes by which they form (speleogenesis) and change over time (speleomorphology). The term "speleology" is also sometimes applied to the recreational activity of
Exploration Earth: The Time Machine BBC Radio 4. "Exploration Earth: The Time Machine" was released on CD, paired with "Genesis of the Daleks", in 2001. It was also given away on its own as a free CD with the 28 April 2010 edition of "The Daily Telegraph" newspaper via WHSmith. It was re-released on CD in The BBC Radio Episodes but this time paired with What Happened to...Susan?, a 1994 spoof from the radio comedy series What Happened to...? Exploration Earth: The Time Machine "Exploration Earth: The Time Machine" is an episode of the BBC Schools radio drama series "Exploration Earth", a series exploring geography.