I am a visitor to your planet from Rigel IV. My kind mastered intergalactic travel eons ago and ventured far and wide to the universe in our whirling saucers. In the "Jurassic Period," we discovered life forms on your planet and obliterated them completely. Centuries later, while on their way to an auspicious offering, a party of our saucers foolishly fared into your solar system and got lost. Idiots turned left instead of right after passing Jupiter...and, long story short, they found other life forms breeding on your planet. In our absence, your planet had been populated by delicious new life. Being a tad hungry, these lost adventurers ate everyone they could and probed the rest. I believe the children of our first victims on your planet still roam among stupid humans.
I, Kodos, and my brother Kang are here as goodwill ambassadors from Rigel IV. We wish to locate the bearers of our seed and take them with us to Rigel IV.
If you think we are your progenitors, you have to tell us why you think so, and why we should believe you.