Well a palaeontologist studies prehistoric life through the physical remains, kind of like an archaeologist studies human life through its remains. An evolutionary zoologist is a zoologist (ie someone who studies any animal life), but focussing on evolution, which depending on his specialism could be purely modern animals. A palaeontologist certainly wouldn't be on any kind of expedition where they'd be tracking panthers for example, but Nick has been. There would be some crossover between the two disciplines like there is between history and archaeology (although less crossover I would think since there isn't any history that can't utilise archaeology), but they're different.

Honestly Cutter shouldn't have the amount of knowledge he seems to. I would think his knowledge should be more general (ie it's a raptor of some kind rather than it's 'specific species of raptor'). It's slightly sloppy writing in always giving him the answers when they should come from Connor more often.