How do the animals that rangers call affect learning?

Do they work the same as mercs so you get the 2nd person exp bonus?

Do they work like conjurer pets and not affect it at all?

I played a beastmaster before the merc exp changes, but I can tell you that the snakes and wolves are not pets. Only the bear will follow you around. The snakes are basically just an attack. The wolves actually have a mob, but it's more like the hunt where they'll attack the enemy but don't follow you. I think they may chase, but I don't know how quick they can track.

If you're curious if the mob in your group is conventional, i.e. they take away exp when you're grouped, then they'll have NPC next to their name when you use the group command. Conventional likely includes bears and tamed animals of the beastmaster class. You can tell if they add exp, as in a groupmate bonus, because they'll have * by the NPC, again while using the group command.

None of them work like Conjurer pets. The only mobs in the game that work like them are Nightwalkers, as far as I know. Meaning, they're not part of your group but they're treated as if you kill the mob/pc, if they get the final hit, and do not affect the group exp bonus.