Can a human being who can let aliens from interstellar colonize the earth stop it?

In fact, this question is very simple! We are carbon-based creatures (creatures based on carbon elements). According to the performance of carbon-based organisms on the earth, we can temporarily draw the conclusion that the lower the level, the longer the life span. According to our current observation of the universe, in such a long time range, there should be no living things can carry out interstellar for such a long time! Don't say the speed of light will slow down. The closer an object is to the speed of light, the greater its mass will be, which is unbearable for living things!