This spiny mammal is readying itself for a hibernation in which its body temperature will drop from 35°C to 2°C. Normally, a hedgehog would already be hibernating by this time of year, but biologists have suggested that global warming may be the reason that this little guy is still awake. Luckily for their mothers, hedgehogs are born with a protective membrane covering their quills and these quills are eventually used to protect their soft underbellies from predators. Fun fact: A group of hedgehogs is called a prickle.