African bush elephants at Masai Mara National Reserve in Kenya

© Yva Momatiuk and John Eastcott/Minden Picture

Lunch buddies. Giving Tuesday

Social structure in elephant herds is surprisingly complex. The adults in the herd exhibit what scientists call 'reciprocal altruism.' That means that elephants will act in ways that give them no direct benefit—say, protecting or feeding a calf that isn't theirs. They do that because the other elephants in their herd will do the same for them. Maybe the elephant is a good role model for Giving Tuesday?

Always observed on the Tuesday after Thanksgiving in the US, Giving Tuesday began in 2012. It has begun to spread around the globe, as other countries embrace the idea. The purpose of the observance is to encourage everyone to set aside some time to do something good for others. In the meantime, do something good for yourself and take in how wonderfully wrinkly and happy the two elephants look in our photo today. Then test your elephant IQ in today's quiz.