You guys are really overthinking this. The rodent/lemur thing is just a description from a first-draft story outline, not a finished text or a technical dissertation. It's just to give a rough visual idea of the sort of thing he was tentatively thinking about. Heck, he probably knew he'd be unlikely to have the budget to actually film the thing. But that's what you do in a first draft. You let your imagination run wild at the start, and then, later, you apply realistic limits (whether conceptual or budgetary) and pare it down to what you can practically film.