If rats are intelligent ..?

  why do they mistake fingers for treats?



I always put carrot sticks and other various vegetables high up between the bars or the cage so my rats have to climb to get them.



My little sister put her finger through the bars this morning and got bitten.



Why cant they tell the difference between a treat and a finger?
Rats are very nearsighted and if her finger smelled like something edible it only makes sense that they would bite/nip at her finger. It's not that they're not intelligent ... they're just very nearsighted.



You also mentioned you put the carrots between the bars for them to grab. If they're used to this and your sister put her finger between the bars then they could have mistaken her finger for a carrot or something.
They have terrible eyesight. Visually, they can't tell the difference. All they see is something sticking in their cage, so they tap their teeth against it to see if it moves. If it does, then they leave it alone.
well some rats just do that. i had one rat that used to do that because i fed him treats through the bars. he didnt bite hard. he would just grab my finger, then let go when he realised what it was
I had a rat for four years and it never once bit me! Perhaps it just doesn't like you too. hahah.