Knowledge: During UN meetings, all presidents eat the same type of food. On the other hand, manta rays eat whatever they find but sharks only eat fishes.

Conversation:
Once I swam with a manta ray.
Sounds interesting, was it a manta ray? They're one of the largest rays on Earth.
I really don't know they were pretty large, do you know anything else?
Gerald Krefft, Australian Museum's director, described them in 1868.
Interesting, how similar are rays to sharks anyway?
Well, both share parts like a horn-shaped cephalic fin as well as big, forward-facing mouths.
That is cool to know. Do you also know if they like the same type of food?

Response: No, manta rays eat whatever they find but sharks only eat fishes.