Most animals do it. You’ve been doing it since before you were even born. And it’s quite likely looking at these photos has made you do it now. Yawning. But why do we yawn and why is yawning so contagious?
Chimpanzees use blades of grass to ‘fish’ for termites, and capuchin monkeys use a hammer and anvil to crack open nuts. A mandrill has even been seen using a stick to get dirt out from under his toenails. We’ve known for a long time that other primates use tools but how about animals that aren’t our close relatives?
Will wearing red help you pick up? Do sports team dressed in black play more aggressively? Are good guys in movies often dressed in white? We all have instinctive responses to colours and in the case of food packaging, marketers are very keen to exploit them.