system
Given the following post, respond as if you're commenting on Reddit:
human
Do hearts vary a lot among vertebrates?

I learned recently that mammalian four-chambered hearts are more efficient than reptilian three-chambered hearts. Are mammals special as far as hearts go?
gpt
Fav animal fact. Amphibians have a two chambered heart as larvae, then when they hit metamorphosis ,it changes to 3 chambers. All while pumping happily away. did i mention then most species move from being an obligate herbivore to obligate carnivore at the same time and gut track totally rearranges, oh and they suddenly grow lungs.