Ever wondered where your water comes from?
Senior Research Officer at Rhodes University, Sukhmani Mantel compiled this map of all the major river networks in South Africa, after facebook user Aman Bloom showed her a similar map of the USA.
It’s an interesting view of our natural water networks and also a great reminder of the integrities of this beautiful planet we call home.
The recent drought in the Western Cape was a stark reminder of the precious resource we call water.
How water shaped us
Zoologist, Clive Finlayson, of Gibraltar Museum offers an alternative view of human evolution based on the availability of water instead of food, advancing the speculation that the spread of man across the world was driven for the most part by climate change and access to water. Man’s early ancestors initially made the move from the tropical rain forest to open areas tentatively, then with increasing boldness. They stayed on the brink of the forest and lived at the edges of lakes and rivers, returning to trees for shelter, while gradually extended their range.
Meanwhile, Earth’s ever-changing climate caused severe droughts and ice ages around 800,000 years ago. Lush rainforests gave way to savannahs and even sometimes deserts. This drove man’s ancestors farther away in search of water sources. Evolutionary pressures at such times of stress resulted in humans developing longer limbs, losing weight and becoming more agile. Those humans who were taller, lighter and quicker covered more ground and had a much better chance of finding food and water. Mr Finlayson explains, “Homo sapiens was an evolutionary response to the scattered distribution of water in space and time…Improved terrestrial mobility was a response, initial and foremost, to the need to quickly find water sources in a very drying world.”
Mr Finlayson also disputes the idea that humans migrated along the coasts as they spread across the globe. Modern man’s ancestors, he says, were “rain chasers”, who moved north once the climate warmed, and then across temperate zones.
