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.
Emperor penguins, Aptenodytes forsteri, feed on small pelagic (open water) fishes, crustaceans, and cephalopods. Adults and juveniles are preyed on by leopard seals, orca (killer whales), and sharks; chicks are preyed on by skua gulls (pictured above) and Antarctic giant petrels.