GPT-3 is confused about ducks, chickens, and eggs

Mark Liberman reports some puzzling conversations with GPT-3.  The first conversation:

Me: Do ducks lay eggs?
GTP-3: Yes, ducks lay eggs.
Me: What do you mean by that?
GTP-3: Ducks lay eggs .
Me: Do all ducks lay eggs?
GTP-3: Yes, all ducks lay eggs.
Me: What about lions?
GTP-3: I'm not sure about lions.
Me: Do lions have manes?
GTP-3: I’m not sure about lions.

The beginning of the second one:

Me: Where do eggs come from?
GTP-3: Eggs come from chickens. Chickens lay eggs and then farmers collect them to sell.
Me: What about ducks? Do they lay eggs?
GTP-3: Yes, ducks also lay eggs. Duck eggs are often used in Chinese cuisine.
Me: What about roosters? Do they lay eggs?
GTP-3: No, roosters do not lay eggs.
Me: Are roosters chickens?
GTP-3: No, we consider roosters and chickens to be two different types of poultry. 

There's more at the link.