Self Improvement Wednesday

Most people know that extinction is the end of a living species or group of species but our scientific knowledge goes well beyond this. Take a listen to this week's lesson with

Richard Kingsford, Professor of Environmental Science at the University of New South Wales.

The tadpoles of some frog species remain unknown to science, years after the adult frog is discovered. However, being able to identify the species a tadpole belongs to is vital for understanding the species and helping conserve it. Take a listen to this great lesson from Dr Jodi Rowley, Curator of Amphibian & Reptile Conservation Biology at the Australian Museum.

The technologies that allow us to move across our city are much discussed, but what about those that enable us to move up and down in our cities? Take a listen to this week's fascinating lesson about lifts, with Associate Professor Kurt Iveson, Urban Geographer at the University of Sydney.

This week saw the anniversary of one of the most catastrophic volcanic eruptions in recorded history - Krakatoa, a volcano in the Sunda Strait between Sumatra and Java. Take a listen to this week's lesson with Tom Wright, Artistic Associate at Belvoir.

Have you ever seen one? Many say they have and debate has raged for many years - do big cats roam free in the Australia?. The main sighting is normally that of a large black cat, a black panther, well do they exist and what evidence is there, is it even possible? Take a listen to this week's lesson with Ben Britton, Director of the Wild Cat Conservation Centre.

Most flowering plants reproduce by producing seeds or by pollination, but some species have given up this process altogether. They just clone themselves. Take a listen to this week's lesson with Dr Brett Summerell, Chief Botanist at the Royal Botanic Garden Sydney.

History shows us that astronomy and troubled times go well together. Take a listen to this week's fascinating lesson with Fred Watson, astronomer-at-large.

Insects have a vast array of weaponry - they bite, they sting, they spray, they infest and they've even been used as military weapons in warfare! Take a listen to this week's fascinating lesson with Dr Eliza Middleton from the Invertebrate Behaviour and Ecology Lab at the University of Sydney.

Kara Walker is a contemporary American artist widely known for her artworks that examine race, gender, sexuality and identity. Take a listen to this week's lesson with Elizabeth Ann Macgregor, Director of the Museum of Contemporary Art.

The Greenland Shark can live more than 500 years. Dr Vanessa Pirotta for Self-Improvement Wednesday