Fiona naps underwater
On Monday, the Cincinnati Zoo posted photos on its Facebook page illustrating the seven-week-old hippo's ability to sleep underwater.
In it, staff explained how hippos can not only sleep as such, but can also automatically raise their nostrils above the surface for a breath without even waking up.
Fiona comes up about every 15 seconds. Adult hippos have the lung capacity where they can hold their breath for several minutes.