Great waves of biological invasion sweep us into episode two of Australia: The Time Traveller's Guide. The oceans, replete from the explosion of life that began in the Cambrian, now spill their cargo onto the land. Australia, part of the super-continent Gondwana is truly a wide, brown land with no blush of life to blemish its barren surface. As Dr. Richard Smith discovers, that all changed in the Silurian, as planet Earth's forgotten pioneers - plants -invade the shores. Arthropod armies soon follow. Then, the rise and rise of fish and the emergence of four-legged animals onto the land. Once again, prehistoric life was busy bankrolling our modern economy and building the basic elements that we know and love as the Australia of today.