Common Seals are wonderful and wild animals. This one at Broughton is yawning and showing its teeth perfectly; three front teeth, one eye tooth and five cheek teeth in each half of its upper jaw. It looks like a bear or a weasel, which are their closest land relatives.
All animals with a backbone, including humans, have a diving response; a reflex that is most strongly developed in diving animals. When diving they automatically slow their heart rate and conserve oxygen by sending blood away from their muscles to the essential organs, such as their brain. Common Seals can dive to 450 metres deep and remain underwater for up to 30 minutes. I once spent a week learning about the haemoglobin of diving mammals. They have evolved over millions of years to cope with lack of oxygen and the build up of acid in their bloodstream as they go without breathing. The even manage to avoid getting the bends like human divers can by collapsing their lungs and removing the chance of getting Nitrogen into their bloodstream at depths. Just how cool is that?