can you elaborate on that? give me a specific (theoretical) case that evolution cant explain and show why it will falsify common descent.
i dont think so. even if we never found a single fossil evolution will be just fine with that.
the same is true here. i even showed here that about 50% of cases base on morphology dont fit with the genetics.
so how you can show that its impossible according to evolution to evolve hollow bones again?. there is no such calculation and thus this is only an assumption. evolution has no such bar.