Tigers 101 | National Geographic — Transcript

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1. 0:02with their signature orange fur
2. 0:04and black stripes tigers have become
3. 0:06icons of beauty
4. 0:08power and the importance of conservation
5. 0:12tigers have evolved into six subspecies
6. 0:16the tiger's tale of evolution can be
7. 0:18traced back to about two million years
8. 0:20ago
9. 0:21when the earliest known tiger ancestor
10. 0:23left africa and ventured into asia
11. 0:27over time the big cat split into nine
12. 0:30subspecies
13. 0:32with six still alive today
14. 0:35the most numerous subspecies is the
15. 0:37bengal tiger
16. 0:39accounting for approximately 50 percent
17. 0:41of the tiger population worldwide
18. 0:46tigers are the world's largest cats
19. 0:49on average the big cats weigh about 450
20. 0:52pounds
21. 0:53but the largest is the siberian tiger
22. 0:56subspecies
23. 0:57measuring up to 13 feet long and
24. 1:00weighing up to 660 pounds
25. 1:03this extra weight is primarily because
26. 1:05of large powerful muscles
27. 1:07unlike lions the second largest of the
28. 1:10big cats
29. 1:11tigers have more muscle mass and are
30. 1:13therefore heavier
31. 1:16tigers have webbed toes often living
32. 1:19near bodies of water
33. 1:21tigers have adapted for a semi-aquatic
34. 1:23lifestyle
35. 1:24they appear to enjoy being in the water
36. 1:26unlike most cats
37. 1:28and are excellent swimmers using their
38. 1:30powerful muscles to propel their bodies
39. 1:32in the water
40. 1:34they've also evolved to have webbing
41. 1:35between their toes
42. 1:37the webbing allows the big cats to push
43. 1:39around a greater volume of water with
44. 1:41each stroke of their paws
45. 1:45white tigers are a type of bengal tiger
46. 1:49the classic black and orange coloration
47. 1:51of most tigers
48. 1:53is caused by the pigments eu melanin
49. 1:55which turns for black
50. 1:57and pheomelanin which turns fur orange
51. 2:00the production of pheomelanin is
52. 2:02triggered by the gene slc45a2
53. 2:06white tigers carry a mutated version of
54. 2:08this gene which prevents them from
55. 2:10producing
56. 2:11orange pigmentation
57. 2:15fewer than 4 000 tigers remain in the
58. 2:17wild
59. 2:19at the turn of the 20th century
60. 2:21approximately 100 000
61. 2:23tigers roamed the wild living as far
62. 2:26west as turkey
63. 2:27and as far north as russia but due to
64. 2:30deforestation
65. 2:31human development and poaching their
66. 2:33range severely decreased and
67. 2:36within 100 years the world's tiger
68. 2:38population declined by about 96 percent
69. 2:42[Music]
70. 2:44over the past few decades programs have
71. 2:47been put in place to protect tigers and
72. 2:49their habitats
73. 2:50with the help of the global community
74. 2:52tiger populations may slowly rebound
75. 3:14[Music]
76. 3:16you