Ancient humans hunted Glyptodon, an extinct massive armadillo, in order to live within their shells.
27. The last Kauaʻi ʻōʻō (now extinct) was male. Its song was recorded in 1987. It was recorded singing a mating call, to a female that would never come. It died in 1987 as well.
28. A cave goat (Myotragus bakearicus) that went extinct approximately 5,000 years ago is the first known mammal to have become cold-blooded. Their bone growth rate is unlike any other mammal, and more similar to crocodiles in showing slow and adaptive rates to environmental temperature.
29. The Carolina Parakeet, a neotropical parrot that was native to much of the United States up until they were driven extinct by deforestation, hunting, and possibly disease in 1910. They lived in huge flocks of up to 300 birds and were likely poisonous to eat.
30. In 1875, a swarm of locusts (Rocky Mountain Locust) 1800 miles long and 110 miles wide swarmed through the western U.S., causing $200 million in crop damage. At 12.5 trillion insects, it was the largest concentration of animals ever seen. Less than 30 years later the species had vanished and was declared extinct in 1902.
The extinct American Lion that used to range all over the U.S. and into South America and was about 25% larger than today's African Lion.
32. The Alpine Spaniel, a now extinct dog bred by Augustinian Monks for rescuing travelers stuck in the snow of the Great St. Bernard pass. Dogs were sent in pairs so one could alert the monks when they found someone. They are said to be ancestors of modern-day St. Bernards.
33. The Irish Elk, an extinct species of deer that had the largest antlers of any known deer with a maximum size of 3.65m (12 foot) from tip to tip that weighed up to 40kg (88lb).
34. The once widespread West African black rhino was declared extinct in 2011. The reason for extinction was poaching by humans.
35. The extinct Tasmanian Tiger could open its mouth wider than any other mammal.