"What sort of uses could they have?" He asks, genuinely curious. "I'm still doing my research."

He's read that they were used for pretty much everything. Headaches to illness to hysteria, leeches were rather popular as a medicinal use during the 19th century on Earth. Perhaps he should ask the other humans about it as well, and get a better idea of how the creatures functioned. It might serve him well to find some medicinal use for them.

"I've read that they can be used for just about anything, though the actual results from this vary from case to case."