I hope they don't either. However, science does not understand how biology generates conscious experience, and I suspect it never will.
Consider aliens coming upon a man with "locked in syndrome", where he can feel and sense his environment normally but is completely unable to act, speak, etc. They could burn him and measure his chemical response (which is similar to plants), but they may ultimately conclude he felt no pain because he did not protest, when in fact he felt it very intensely.
very true!!! good example