African elephant
Photo by Marsel van Oosten, Lower Zambezi National Park, Zambia
“The elephants in this area have relatively small tusks, and many of them have no tusks at all. This is the result of what is called ‘reverse evolution’ – the survival of the weakest. Poachers target the biggest bulls with the largest tusks, so their genes are eliminated from the gene pool. The weakest bulls – those with small tusks or even no tusks at all – survive and get to procreate.”
Great white shark
Photo by Chris Fallows, Stewart Island, New Zealand
“New Zealand, Australia and the North American
