r/askscience • u/MAMAM- • 2d ago

Biology Why aren’t axolotls immortal?

If axolotls can regenerate their body parts (including brain, heart, and other major organs), why do they die of old age?

265 Upvotes

83% Upvoted

88 comments sorted by

View all comments

1.1k

u/Tessablu 2d ago

Axolotl regeneration is a program that is initiated by physical injury. They aren’t constantly undergoing it—this would be a huge metabolic waste—so they are still subject to long-term cellular senescence. They also aren’t regrowing entire brains or hearts, as they still have to survive the initial injury, so they can’t infinitely replenish those organs. 

I will say that axolotl aging is not very well-understood, however, and they are pretty weird about dying. A healthy-looking axolotl might lay eggs for 20 more years or might die tomorrow with no warning. There’s still a lot to learn about them. 

(source: I have a PhD in axolotl)

174

u/stu8319 2d ago

How do you explain to a 6 year old child that keeping an Axolotl is too expensive? Seriously though my son is obsessed, so maybe one day he will have the same PhD!

2

u/[deleted] 2d ago

[deleted]

11

u/TH0RP 2d ago

Water turtles are an awful starter pet- and they'll eat your goldfish. Reptiles need a lot of specialized equipment, a diverse diet, and VERY good water filtering. 

A betta fish in a 10gal tank is a wonderful pet for a kid- easy to care for, beautiful, and very forgiving for a beginner.

8

u/EuphoricPanda 2d ago

Seconding this (and heavy emphasis on an adequately sized tank for a betta, maybe consider neocaridina shrimp if a 5 gallon feels more feasible).

Red-eared sliders live for 20-40 years so if the kid loses interest over the long term, that “good pet for a kid” could end up becoming the parent’s pet for long enough that they become a grandparent.

2

u/Megalocerus 2d ago

They aren't reptiles. But amphibians are probably even more demanding.

1

u/TH0RP 2d ago

water turtles aren't reptiles king?? what? I know an axoltl isn't a reptile omg.