Atrial fibrillation (AF or A-fib) is an abnormal heart rhythm characterized by rapid and irregular beating.
Emperor penguin - Aptenodytes forsteri. This is the largest species of penguins. Emperor penguins are only found on and around the Antarctic continent, on the thick pack ice and rarely on mainland. They have a pale yellow, open (breast and chin patch are one) patch on chin and breast. A long, thin and curved bill, typical for fish eaters. Very dark grey back and blue black head.
Penguins on land. On land little penguins live in holes in the ground known as burrows. These burrows provide a place for little penguins to rest, nest and moult. Burrows also provide protection from predators and extreme heat.