40 Unique Animal Facts that you should know

Every organisms on Earth have its own quality. Some of them have such a unique features that they stands out and worth to mention. Some facts are like hard to believe as it's way different that what we usually thinks. Lets go through those unique/interesting Animal Facts.

1. Octopus is the animal with three hearts.
2. Hummingbirds can fly backwards.
3. Crocodile cries after having meal.
4. Only female mosquitoes bite.
5. Fish never blink their eyes.
6. Polar bear have black skin.
7. Earthworm have both male and female organ in same body.
8. Crocodiles cannot takes its tongue out.
9. Crab have teeth in the stomach and don't have head.
10. Star fish don't have a brain.
11. Hyena is the animal that laugh like human. 
12. Blue whale weights equivalent to three grown elephants.
13. Some lizard and salamanders detach their tail themselves on defense process. 
14. Shrimp have hearts in its head.
15. Rhino secrets red sweat when it gets angry.
16. Koala fingerprints are indistinguishable from human.
17. Butterfly is organism with many eyes.
18. Elephants is the only animal that can't jump.
19. Cockroach can alive for many days without its head.
20. Otters hold hand while sleeping so they don't float away from each other
21. Dolphin shed their skin 12 times a day to increase swing efficiency with smooth skin.
22. Sloth speed is 0.15 mph.
23.  Bat is the flying mammal actually not a bird and have a mammary gland.
24. One species of jellyfish is immortal.
25. Yarsagumba (Ophiocordyceps sinensis) lives half life as animal and half life as plant.
26. Owls don't have eyeballs but have eye tubes.
27. Elephants can hear from legs.
28. Ants on Earth have population of 1 quadrillion (one million billion).
29. Cockroach have white blood.
30. Squirrels are responsible for planting thousands of tree worldwide.
31. Dogs secrets sweats from tongue.
32. Pigs physically unable to look up into the sky.
33. Giraffe is a dumbest animal.
34. Chimpanzee never cry tears.
35. Tortoise have the longest life-span.
36. Cricket have ears in legs.
37. Butterfly have tongue in legs. 
38. Deer breath through both eyes and nose.
39. Giraffe can't produce voice even if it has tongue but don't have vocal chords.
40. Horse can sleep standing.