Atrial fibrillation (AF or A-fib) is an abnormal heart rhythm characterized by rapid and irregular beating.
Emperor penguins owe their scientific name (Aptenodytes forsteri) to their discoverer, the first natural scientist to reach Antarctica, the German Johann Reinhold Forster. Forster came to Antarctica in 1770, on Captain James Cook's ship, and saved Cook's life during the voyage.
There are 17 species of penguins some of which are found as far north as the equator. Penguins are categorized into three families: brush-tail, crested, and king/emperor penguins. Of the 17 species only six are found in Antarctica (AdÃ©lies, Chinstraps, Emperors, Gentoos, Macaronis, and Rockhoppers). Penguins often are referred to as flippered flyers due to their effortless movement through the water and their possible evolution from gull-like birds.