Homo sapiens evolved over the last million years during which time the climate fluctuated strongly. Ice accumulated and melted again, exposing and flooding the continental shelves - land which was colonised by plants and animals. About 3000 such prehistoric sites with archaeological remains have been found on the sea floor by divers.
The talk starts: "This evening I want you to get used to going backwards in time. We will start at about 2500 years ago, and accelerate backwards to 1 million years ago during the next hour. That makes approximately 15,000 years per minute, going backwards, and most of the journey is underwater. Also, I plan to dart about the world visiting every continent except Antarctica, so I am assuming that your geography is pretty good.
Everybody has read about underwater cities at some stage, and most people are aware that there are flood myths in almost every cultural tradition. I am going to start with standard underwater Greek and Roman cities in the Mediterranean, and then work backwards through the Bronze Age, Neolithic, Mesolithic and Palaeolithic, finally considering the earliest Stone Age cultures, in that order, and always on the floor of the sea."
http://www.gresham.ac.uk/lectures-and-events/humanity-and-a-million-years-of-sea-level-change
https://www.youtube.com/watch?v=J-d74TWJxwM
With thanks to kerrykelty for the link
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