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. Description & Behavior. The scientific name for emperor penguins, Aptenodytes forsteri (Gray, 1844), is made up of Aptenodytes, which means featherless diver and forsteri, for J.R. Forster, a naturalist and colleague of Captain Cook in the 18th century who was one of first to describe penguins.