Well then, what explanations have been seriously considered for these rather obvious apparent perturbations? ----Besides meteor impacts and random environmental disasters? More important, how could we be sure that the handy explanations are covering the whole waterfront?

I allow that "intelligent" influence there in those "many" cases is quite plausible. Just too convenient and beguiling for you, then?

That will be a great triumph for mankind then, the day we deter a meteor or asteroid that is directed at us. (Maybe the "higher intelligence" is not always playing in our favor?)

Frank:""Capricious supernatural meddlers are not within the reach of science and need not be considered when one is trying to understand the history of life from a scientific point of view."

But possibly something "supernatural", like the planet Uranus eventually became known to astronomers? That is, unknown but mysteriously influencing Neptune's orbit, although not known. I don't embrace the arbitrary conceptual division between natural and "supernatural", so you are seeming to project something on me.

In brief: Higher intelligences in the universe can be entirely natural.

Maybe "it" doesn't even know for sure if it was alone at the beginning, IF there was a "beginning"?

Summary: I am not presuming to know the unknown, just allowing by inference that there is higher intelligence around, by geometric analogy, that could have been interested in progress of life on Earth.