When the 2004 Indian Ocean Tsunami hit the Bond Island of Ko Khao Phing Kan (situated north of Phuket island in Thailand), a destination attracting millions of tourists, little did we know that it is in fact the ocean that has been the primary cause of the world's periodic mass extinctions over the past 500 million years.
This announcement was made earlier this week by Shanan Peters, assistant professor of geology and geophysics of the University of Wisconsin-Madison (US). According to his research published in the scientific journal, Nature, he suggests that changes in ocean environments related to sea level exert a driving influence on rates of species extinction, in which animals and plants survive or vanish, and generally determine the composition of life in the oceans.
Although we are talking in term of long geological timelines here, these observations hold some important findings on the relevance of climate change to mass extinctions. We know that throughout the geological history of the planet, the oceans have expanded and contracted as part of continental plate movements and changes in the climate. Similarly sea levels have changed as a result of these planetary changes explaining why in some parts of the world we can find coral remnants far inland. Whilst evidence gathered over many years show that a number of ocean species became extinct as a result of these dramatic changes, to date such a link between the ocean and mass extinctions were not clearly understood. Peters provided such evidence throwing doubt on the role of asteroids and super-volcanoes in mass extinctions.
Whilst it is those same sea level changes that allowed many islands and continents to be colonised, changes in our present climate driven by human influence may eventually contribute to such disastrous tipping points: mass extinctions. The point here to not to advocate present climate change as a mass extinction phenomenon but as a signal to human civilisation that nature indeed cannot be pushed to its limits - the rebound can be disastrous.
Upsetting the natural balance of the oceans, such as too much fresh water as a result of the melting ice caps has already triggered sea level rise, if we do something about it sound enough, we may avert another global catastrophe - mass migrations of coastal and island peoples.
'I hope you can swim, Goodnight' (Quote from Bond in The Man with the Golden Gun, 1974).
Further reading: http://www.nsf.gov/news/news_summ.jsp?cntn_id=111722&org=NSF&from=news
Video interview: http://nsfgov.httpsvc.vitalstreamcdn.com/nsfgov_vitalstream_com/fossil.swf