Similarly, physics would ignore something based on how influential it is to the things its modelling.
Gravity often isn't included in electromagnetism because it's practically unnoticeable. For most electrodynamics it's 10^40 times weaker than the EM field.
It would be equivalent to taking into account a pathogen that existed in the Cretaceous when describing the lifestyle of a lynx.
The thing is I could include them all at once if I wanted to. I could literally formulate the Standard model in curved spacetime, which would be able to handle any physical phenomena we've ever observed.
We just don't do this because we don't have to.
I think fundamentally they are the same, it's just that biology has to include more noise on average than physics does.
Almost all of modern physics includes "corner-cases", heck that’s all Quantum Chromodynamics is. To solve anything in it, you have to include all cases.
Anyway, I'm probably going off-topic.