Is as I say, there is zero proof or evidence, scientific or otherwise that abiogenesis on this planet may have happened more than once. But hey, feel free to believe in space alien peoples.
You are completely ignorant as to what science say.
Scientists who have hypotheses that life were started by extraterrestrial, they weren’t talking about UFO or alien civilisation.
The people who do research on Abiogenesis where life started on Earth, trying to do experiments to recreate the condition of early Earth history, to make amino acid. (For instance, the
Miller–Urey experiment, performed in the early 1950s.)
The chemical compounds of certain chains of amino acids (there are many different types of amino acids) are what protein made out of.
Proteins are one of major components required for life, as well as carbohydrates and nucleic acids (eg DNA & RNA); these three biological compounds are what biologists and biochemists called living matters.
Those scientists propositioning hypotheses that life could have started extraterrestrial origin, are not so wild at all.
They are talking about amino acids found in meteorites and comets that have crashed to Earth.
A large meteorite, called Murchison meteorite, broke up in the sky and crashed in several places not far from small Australian town called Murchison. Collecting all the pieces of meteorite is that have a total mass of just over 100 kilograms.
What scientists discovered upon the meteorite was over 90 different types of amino acids.
Asteroids and meteorites in space are debris from previous nearby supernovas. And these debris are old as the solar system. They are composed of different types of metals and minerals. But the existence of amino acids in meteorites tell us that these can survive in the harsh environment of space and be preserved in the meteorite.
During the early Earth history, the Earth was bombarded frequently by comet and meteorites. The possibility that some of these meteorites and comets might contain amino acids, are very high.
Like I said before extraterrestrial origin don’t mean your strawman claim of “space alien people”. They are talking about amino acids found in meteorites, not extraterrestrial people.
You would know this if bothered to a little reading and research, instead making up nonsense about “space alien people”.
And the discovery of these amino acids in the Murchison meteorite is just one evidence of many evidences supporting the extraterrestrial origin. So it isn’t “zero evidence” as you’ve claimed.