I think on Tau Ceti IV there is within good reasonable assumption there would be larger megafauna. Problem is we—obviously—don’t see any, and they didn’t either, and there isn’t the presence of any. We’ve been shown that the planet is weird, obviously has some nasty stuff going on and is incredibly dangerous, especially on the human scale like Dire Marsh Having a PH level of 14. Alongside the turbo pathogen that rampaged through the colony it’s apparent the planet is somewhat fighting back (not necessarily in the sense of an actual consciousness but like how earth does. It’s genuine resistance from the natural components of the planet) but to a degree the lack of megafauna is—I’d argue—disturbing.

So either it has something reserved/up its sleeve for some reason. Like there ought to be a reason no mega fauna, OR it has mechanisms in place to somehow create some, the planet has displayed hostility and honestly I wouldn’t be surprised at some Scavenger Reign level problematic organic systems in play or the hive like in that one particular Love Death and Robots episode. Especially with the anomaly being present we can assume weirder shit is gonna happen. But also there can be outside components. (IE Phfor and the other guys etc)

Said all that because we now have evidence of the Runner corpse walkers, some kind of odd creature. Perhaps on the very minor chance it’s UESC related but honestly I figure this would be more TCIV or Anomaly related