Here are 25 Alligators facts.
1-5 Alligator Facts
1. Alligators do not have sex-determining chromosomes. Instead, the sex is determined by the temperature of the environment the alligator is in. – Source
2. A man once jumped into alligator infested waters, screamed “F*ck you alligators” and was subsequently eaten alive. – Source
3. Alligators have been a long-running problem for NASA, including climbing over their fences and entering buildings overnight. – Source
4. Alligators in Louisiana have learned to balance sticks on their snouts specifically during egret and heron nesting season when the birds are actively searching for nest materials. This is the first known case of predators using lures based on seasonal prey behavior. – Source
5. Playing a B flat on a tuba arouses male alligators. – Source
6-10 Alligator Facts

6. Alligators are native only to the United States and China. – Source
7. An alligator’s immune system can fight HIV. – Source
8. Alligators are more closely related to birds than they are other species of reptiles. – Source
9. Alligators’ voices change when they inhale helium, just like humans, implying reptiles have similar vocal mechanisms to human beings. – Source
10. Alligators breathe only in one direction through their lungs. – Source
11-15 Alligator Facts

11. Smiley, an American alligator living at Gothenburg’s Maritime Museum, died after the heat was turned down in her pond to save money. – Source
12. Alligators can go without food for up to 3 years. – Source
13. In 2012, a Florida man had his hand bitten off by an alligator and he was later charged with illegally feeding the animal. – Source
14. Alligators have no finite lifespan, but continue to live forever unless affected by their environment. – Source
15. South FL is the only place in the world where alligators and crocodiles coexist naturally. – Source
16-20 Alligator Facts

16. Alligators can climb trees. They like to bask on rocks, but if there are no rocks available, they’ll climb a tree and bask on a branch instead. – Source
17. Alligators can make their heartbeat as low as 1 beat per minute (making a Python think he is dead and swallow him) the alligator may recover in ~13 minutes and fight from the inside of the Python which can be devastating to the snake. – Source
18. Alligators have a permanently erect penis. It is pushed out by two muscles contracting. There is no muscle in the penis, just collagen. – Source
19. In the early 1900s, the city of Chattanooga kept two alligators in a fountain to keep birds, dogs, and vagrants away. They were eventually removed because the fence was low and they would frequently escape. – Source
20. Only 12 alligators in the whole world have a rare genetic condition that reduces the color pigmentation in their skin. They are known as Albino Alligators. – Source
21-25 Alligator Facts

21. Alligator farms exist, where Alligators are raised for consumption. – Source
22. The world’s oldest known alligator, Muja, lives in the Belgrade Zoo and survived WWII, during which the Zoo was almost completely destroyed, and the NATO bombing of Yugoslavia in 1999. – Source
23. On July 2nd, 1843, an alligator reportedly fell from the sky. – Source
24. Male alligators make a rumbling sound so low it can’t be heard by humans and makes the water dance around them. – Source
25. Alligators’ teeth aren’t as sharp as other predators’ because they are made for crushing, not chewing. When their prey is too big to be swallowed whole, they stash carcasses away to be eaten once the flesh has rotted and is soft enough to eat. – Source
#14 is not true. This is an old assumption based on very uninformed observations.
You are correct. Many live over 100 years but none live forever.
If they all change sex according to the temperature, how do they breed? Whichever other alligator they are trying to breed with will surely be in the same location and be the same sex due to the facing the same environmental (temperature) pressure.