1. The earth's atmosphere is composed of about 78% nitrogen, 21% oxygen, and 1% other gases.
2. The highest point on Earth is Mount Everest, which stands at 29,029 feet (8,848 meters) tall.
3. The lowest point on land is the Dead Sea, which is about 1,401 feet (427 meters) below sea level.
4. The world's largest coral reef system is the Great Barrier Reef in Australia.
5. The world's largest desert is the Sahara Desert in Africa, which covers an area of about 3.6 million square miles (9.2 million square kilometers).
6. The world's largest ocean is the Pacific Ocean, which covers an area of about 63.8 million square miles (165.2 million square kilometers).
7. The world's largest waterfall by volume is the Angel Falls in Venezuela.
8. The world's tallest tree is a coast redwood named Hyperion, which stands at 379.7 feet (115.7 meters) tall.
9. The world's deepest ocean is the Pacific Ocean's Mariana Trench, which reaches a depth of about 36,070 feet (10,994 meters).
10. The world's longest river is the Nile River, which stretches for about 4,135 miles (6,650 kilometers).
11. The world's largest mammal is the blue whale, which can reach lengths of up to 100 feet (30 meters) and weigh as much as 200 tons (180 metric tonnes).
12. The world's fastest land animal is the cheetah, which can run at speeds of up to 75 miles per hour (120 kilometers per hour).
13. The world's largest amphibian is the Chinese giant salamander, which can grow up to 6 feet (1.8 meters) in length.
14. The world's smallest mammal is the bumblebee bat, which is about the size of a bumblebee and weighs less than a penny.
15. The world's largest bird is the ostrich, which can grow up to 9 feet (2.7 meters) tall and weigh up to 350 pounds (160 kilograms).
16. The world's longest snake is the reticulated python, which can reach lengths of up to 33 feet (10 meters).
17. The world's largest rodent is the capybara, which can weigh up to 140 pounds (64 kilograms).
18. The world's largest flower is the rafflesia arnoldii, which can grow up to 3 feet (1 meter) in diameter.
19. The world's oldest tree is a bristlecone pine named Methuselah, which is about 4,800 years old.
20. The world's largest land animal is the African elephant, which can weigh up to 14,000 pounds (6,350 kilograms).
21. The world's smallest bird is the bee hummingbird, which is about 2.25 inches (5.7 centimeters) long.
22. The world's largest lizard is the Komodo dragon, which can grow up to 10 feet (3 meters) in length and weigh up to 200 pounds (91 kilograms).
23. The world's largest fish is the whale shark, which can grow up to 40 feet (12 meters) in length.
24. The world's fastest bird is the peregrine falcon, which can dive at speeds of up to 240 miles per hour (386 kilometers per hour).
25. The world's largest reptile is the saltwater crocodile, which can grow up to 23 feet (7 meters) in length and weigh up to 2,200 pounds (1,000 kilograms).
26. The world's largest spider is the goliath bird-eating spider, which can have a leg span of up to 12 inches (30 centimeters).
27. The world's tallest animal is the giraffe, which can reach heights of up to 18 feet (5.5 meters).
28. The world's smallest reptile is a species of chameleon called Brookesia micra, which is only about an inch (2.9 centimeters) long.
29. The world's fastest fish is the sailfish, which can swim at speeds of up to 68 miles per hour (110 kilometers per hour).
30. The world's smallest primate is the pygmy marmoset, which can fit in the palm of a human hand.
31. The world's largest mammal migration is the annual migration of the Serengeti wildebeest, which can involve up to 1.5 million animals.
32. The world's largest jellyfish is the lion's mane jellyfish, which can have tentacles that stretch up to 120 feet (36.6 meters) long.
33. The world's largest bird is the ostrich, which can stand up to 9 feet (2.7 meters) tall and weigh up to 320 pounds (145 kilograms).
34. The world's deadliest animal to humans is the mosquito, which can spread diseases like malaria, dengue fever, and Zika virus.
35. The world's largest mammal is the blue whale, which can grow up to 100 feet (30 meters) long and weigh up to 200 tons.
36. The world's smallest mammal is the bumblebee bat, which weighs only about 2 grams.
37. The world's largest cat is the Siberian tiger, which can weigh up to 660 pounds (300 kilograms).
38. The world's most venomous snake is the inland taipan, which can inject enough venom in one bite to kill up to 100 humans.
39. The world's tallest tree is a coast redwood named Hyperion, which stands at about 379.7 feet (115.7 meters) tall.
40. The world's largest bear is the polar bear, which can weigh up to 1,500 pounds (680 kilograms).
41. The world's largest turtle is the leatherback sea turtle, which can weigh up to 2,000 pounds (907 kilograms).
42. The world's smallest fish is the Paedocypris fish, which is only about 0.3 inches (7.9 millimeters) long.
43. The world's largest land predator is the polar bear, which can weigh up to 1,500 pounds (680 kilograms).
44. The world's smallest reptile by body size is a species of gecko called the dwarf gecko, which is only about 0.6 inches (1.6 centimeters) long.
45. The world's largest rodent by weight is the South American capybara, which can weigh up to 140 pounds (64 kilograms).
46. The world's largest butterfly is the Queen Alexandra's birdwing, which can have a wingspan of up to 12 inches (30 centimeters).
47. The world's smallest bird is the bee hummingbird, which weighs only about 2.6 grams.
48. The world's largest amphibian is the Chinese giant salamander, which can grow up to 6 feet (1.8 meters) long.
49. The world's smallest mammal by length is the Kitti's hog-nosed bat, which is only about 1.1 to 1.3 inches (2.8 to 3.3 centimeters) long.
50. The world's tallest mammal is the giraffe, which can grow up to 18 feet (5.5 meters) tall.
51. The world's largest land animal by weight is the African elephant, which can weigh up to 14,000 pounds (6,350 kilograms).
52. The world's longest insect is the Chan's megastick, which can grow up to 22 inches (55.5 centimeters) long.
53. The world's largest rodent by length is the Malayan giant squirrel, which can grow up to 3 feet (91.4 centimeters) long.
54. The world's most venomous fish is the stonefish, which can cause excruciating pain and even death if stepped on.
55. The world's largest spider by leg span is the Goliath bird-eating spider, which can have a leg span of up to 12 inches (30 centimeters).
56. The world's fastest land animal is the cheetah, which can run up to 75 miles per hour (120 kilometers per hour).
57. The world's largest rodent by height is the capybara, which can stand up to 2 feet (61 centimeters) tall at the shoulder.
58. The world's longest snake is the reticulated python, which can grow up to 30 feet (9 meters) long.
59. The world's largest rodent by tail length is the African crested porcupine, which can have a tail up to 20 inches (50 centimeters) long.
60. The world's deadliest plant to humans is the castor bean plant, which contains a deadly toxin called ricin.
61. The world's largest flower is the Rafflesia arnoldii, which can grow up to 3 feet (1 meter) in diameter.
62. The world's tallest tree is the coast redwood, which can grow up to 379 feet (115.7 meters) tall.
63. The world's largest reptile by weight is thesaltwater crocodile, which can weigh up to 2,200 pounds (1,000 kilograms).
64. The world's fastest bird in level flight is the white-throated needletail, which can fly up to 105 miles per hour (169 kilometers per hour).
65. The world's largest living organism by area is a honey mushroom fungus in Oregon, which covers an area of about 2,200 acres (890 hectares).
66. The world's deepest oceanic trench is the Mariana Trench, which reaches a depth of about 36,070 feet (10,994 meters).
67. The world's largest coral reef system is the Great Barrier Reef, which stretches over 1,400 miles (2,300 kilometers) off the coast of Australia.
68. The world's largest desert is the Antarctic desert, which covers an area of about 5.5 million square miles (14.2 million square kilometers).
69. The world's largest cave system is the Mammoth Cave system in Kentucky, USA, which has over 400 miles (643 kilometers) of explored passageways.
70. The world's largest land predator is the polar bear, which can weigh up to 1,500 pounds (680 kilograms).
71. The world's fastest marine animal is the sailfish, which can swim up to 68 miles per hour (110 kilometers per hour).
72. The world's largest living reptile is the saltwater crocodile, which can grow up to 23 feet (7 meters) long.
73. The world's most venomous spider is the funnel web spider, which can be found in Australia.
74. The world's largest ocean is the Pacific Ocean, which covers an area of about 63.8 million square miles (165.2 million square kilometers).
75. The world's tallest mountain is Mount Everest, which stands at 29,029 feet (8,848 meters) tall.
76. The world's smallest mammal by weight is the bumblebee bat, which weighs only about 2 grams.
77. The world's most poisonous plant is the Aconitum plant, also known as the "Queen of Poisons."
78. The world's largest bird is the ostrich, which can stand up to 9 feet (2.7 meters) tall.
79. The world's largest land animal is the African elephant, which can weigh up to 14,000 pounds (6,350 kilograms).
80. The world's smallest bird is the bee hummingbird, which is only about 2.4 inches (6 centimeters) long.
81. The world's most venomous fish is the stonefish, which can be found in the Indo-Pacific region.
82. The world's largest rodent is the capybara, which can weigh up to 140 pounds (64 kilograms).
83. The world's most endangered animal is the vaquita porpoise, which is found only in the Gulf of California and has a population of less than 30 individuals.
84. The world's largest butterfly is the Queen Alexandra's birdwing, which can have a wingspan of up to 1 foot (30 centimeters).
85. The world's most venomous snake is the inland taipan, also known as the "fierce snake," which is found in Australia.
86. The world's largest fish is the whale shark, which can grow up to 40 feet (12.2 meters) long.
87. The world's smallest reptile is the Jaragua lizard, which is only about 0.6 inches (1.6 centimeters) long.
88. The world's fastest land animal is the cheetah, which can run up to 75 miles per hour (120 kilometers per hour).
89. The world's most intelligent animal is widely considered to be the chimpanzee, which shares about 98% of its DNA with humans.
90. The world's most deadly animal, in terms of human fatalities, is the mosquito, which can transmit diseases such as malaria, dengue fever, and Zika virus.
91. The world's largest amphibian is the Chinese giant salamander, which can grow up to 6 feet (1.8 meters) long.
92. The world's largest reptile by weight is the green anaconda, which can weigh up to 550 pounds (250 kilograms).
93. The world's largest rodent is the capybara, which can weigh up to 140 pounds (64 kilograms).
94. The world's smallest primate is the pygmy mouse lemur, which weighs only about 2 ounces (57 grams).
95. The world's largest flower is the Rafflesia arnoldii, which can have a diameter of up to 3 feet (1 meter).
96. The world's smallest fish is the Paedocypris fish, which is only about 0.3 inches (7.9 millimeters) long.
97. The world's most venomous cone snail is the geographic cone snail, which can be found in the Indian and Pacific Oceans.
98. The world's largest invertebrate is the giant squid, which can reach lengths of up to 43 feet (13 meters).
99. The world's most widespread tree is the aspen, which can be found in North America, Europe, and Asia.
100. The world's most common bird is the chicken, with an estimated global population of around 23 billion.
101. The world's largest carnivorous marsupial is the Tasmanian devil, which is found only on the island of Tasmania in Australia.
102. The world's largest living organism is a fungus called Armillaria ostoyae, which covers an area of 2,200 acres (890 hectares) in Oregon's Blue Mountains.