Until 12000 years ago the south of England and the north of France were drained by a substantial river which passed through a vast shallow valley. Rivers which drained into this giant river included Rhine, Meuse, Thames and Schelde,
For most of the previous 50 million years the English Channel was a marine embayment but then the most recent glacier period changed the topography.
The level of the sea has varied considerably and was at some point 20000 years ago the sea was 100 meters below the present levels.
It is now suggested that the level of water in the English Channel is dependent upon the global climate and glacial periods when there is land contact between Britain and Europe.. The existence of the channel depends upon the general temperature and the presence of an ice age or not.
The development of the Channel has had profound effects on migration into Britain. It has also cut Europe adrift from Britain and they have been denied the glories of Cricket, wearing socks with sandals and fish and chips
Gibbard Europe cut adrift Nature 2007, vol 448, 259-60
Gupta S Catastrophic flooding origin of shelf valley systems in the English channel Nature 2007 vol 448 , 342-345
Another interesting paper discusses the origins of modern humans.
Manica et al The effect of ancient population bottle necks on human phenotypic variation , Nature 2007, vol 448, 346-8
This study using human skull measurements supports the hypothesis that modern humans originate from a single location in central or southern Africa. There is a smooth loss of genetic diversity with increasing distance from Africa. Extending as far as the most distant migration across Northern Europe into the Northern and then Southern Americas.
- Martin Eastwood