Is ‘number sense’ our 6th sense?

Plenty of animals, even those that can’t speak, have some kind of understanding of numbers. But what is number sense? How did we evolve it, and what does that mean?
https://elifesciences.org/articles/108701?utm_source=mastodon&utm_medium=social&utm_campaign=organic_insights
#Neruoscience #Cognition