Yeah from what I know we have the archipallium which is the R-Complex or reptilian brain as it is commonly called, then over that we have the paleopallium which is the limbic mammalian brain and over that we have the neopallium which is the new mammalian brain or "neo-cortex" which is found in superior mammals like humans and primates.

Yep, We can certainly do our best to empathize and not commit evil deeds to each other and other species.

You got me curious enough to do some research and found some interesting things. According to national geographic, snakes DID used to have legs. They found some fossils of old snakes that actually had legs.

https://www.nationalgeographic.com/science/phenomena/2015/07/23/a-fossil-snake-with-four-legs/

Crazy huh! and apparently they still carry the genes to grow limbs they are just turned off and would need the right mutations to flip the gene expression back on.

https://news.nationalgeographic.com/2016/10/snakes-grow-legs-evolution/snakes-grow-legs-evolution/