mindblowingfactz: Hippos can sleep underwater using a reflex that allows them to bob up, take a breath, and sink back down without waking up.Photo : cloudzilla / Flickr / wikimedia
mindblowingfactz: Hippos can sleep underwater using a reflex that allows them to bob up, take a breath, and sink back down without waking up.Photo : cloudzilla / Flickr / wikimedia
