How did people find water in the past?

Rhys - To answer the question, we enlisted the help of Dr Ellen Arnold. Ellen is an environmental historian and the editor of the Water History journal:

Ellen - Most of the time people found water by closely observing the natural world around them. There were animal species that gravitated towards permanent sources of water. There were birds that flew towards oases in the desert. There were kinds of grasses and plants - and even weeds - that were more present in wetter ground or more present above higher water tables.

Rhys - So, people probably relied on clues from nature. But what about the second question; did our ancestors just dig until the water table was reached?

Ellen - As Donald pointed out on his question: you can always kinda just dig down and find water. The question is: can you dig deep enough using pre-modern tools and technology? And so watching the signs of nature and then somehow signalling to other people both at the same moment - but also in the future - became an essential task for building cities and water systems and permanent supplies of groundwater.”

Rhys - So it was a combination of piecing together clues from the surroundings, some technological know-how and a group effort that got our ancestors within reach of water. Thanks very much to environmental historian Dr Ellen Arnold. Next time this biting enquiry from listener Sarah.

Sarah - I live in an area with a huge number of mosquitoes that I take every opportunity to kill. I assume that the ones I kill are the weakest and least cunning, which is why I can catch them. Am I, in fact, just creating a master race of mosquitoes by killing off the weakest ones?

Rhys - Thank you, Sarah. So are we unwittingly breeding a master race of mosquitoes? If you’d like to hazard a guess, or you have a question of your own, please email us. That’s chris@thenakedscientists.com or jot down your musings on our forum at nakedscientists.com/forum.