Elephant Matriarch (image) Wildlife Conservation Society Caption In a recent paper in The Royal Society's Biology Letters, conservationists with the Wildlife Conservation Society and the Zoological of London found that the oldest matriarch elephants may retain valuable memories of permanent sources of food and water and their that become crucial in times of drought. Credit (c) Charles Foley Usage Restrictions One-time usage only. Must be used with photo credit. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.