3 ms·

And yet, sharks do it. Also, the skeleton is similarly long lasting and that gets renewed. So why not? Say a finger, which isn't too "expensive in terms of bio

And yet, sharks do it. Also, the skeleton is similarly long lasting and that gets renewed. So why not? Say a finger, which isn't too "expensive in terms of biochemical resources", why not regrow that? Take the acorn worm mentioned, in proportion to the worm regrowing itself must be really expensive. I don't think this too expensive argument explains it.

danans 10y ago
It turns out that while sharks' teeth are functionally analogous to mammal teeth, they have an independent evolutionary origin - they are actually a specialized type of skin scale. http://www.elasmo-research.org/education/white_shark/teeth.htm http://www.elasmo-research.org/education/white_shark/teeth.h... It's apparently one reason why they can replace them constantly.
Ygg2 10y ago
Shark also have rows of them.