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.
The classic tuxedoed penguins are found in Antarctica, along with the largest, the Emperor penguins, while Jackass penguins flourish in Namibia and South Africa and Humboldts live on a desert landscape near the coasts of Peru and Chile.