If you live with a cat or a dog, chances are that your furry companion is at the moment taking a nap. All animals need sleep: sleep hours help us retain what we have learned and are essential for our immune system to function well. But there are species that require sleep longer than others: while humans we spend a third of the day sleeping, adult giraffes rarely sleep more … [Read more...] about Do dogs and cats need sleep as much as we do?