Do UFO sightings have an evolution?

I certainly believe that other life exists out there. Whether that life is some mushroom growing on another planet, or entire civilizations with laser guns and butt obsessions. Whether they have visited us or not, I could never say.
However there do exist UFO and alien sightings, but it seems to me that when you look this stuff up, the sightings themselves, when they’re not all grainy and barely anything, follow what stuff like Hollywood depicts as life out there. Every sighting picture I see seems to look like something from a movie, from some time period or another…although I suppose movies can be influenced by something, rather than creating anything. In fact isn’t this how it usually goes?

For example, check out this UFO from the fifties.

Now let’s move up to the 200’s, here.
These triangles seem all the rage, although I remember a story when I was little, by some teen girl who said she saw a triangle in the night sky while camping with friends, this was like in 1988 or something. Seems a little more evolved than the flying hat from the 50’s, anyway. I also once saw something in the sky that I was not able to define, although that hardly makes it an alien spacecraft.

Alien pictures from the 50’s, I can’t actually find very much. I’d like to know when the ’‘grays’’ first appeared. Anyone know?

I must make a disclaimer, I can’t be sure if the pics I have provided here are actual sightings, or from some obscure movie I don’t know about, sites can say whatever they want, and as I do not pursue such things, I am forced to take it at whatever face value…however the pattern seems a bit evident when you look this up on the Internet; aliens seem to evolve straight with us, so far as they look like, anyway.

What says the company about all this? Are alien sightings our own fabrication? Were there any sightings in the middle ages, are there any actual cavemen caves that feature drawings of humanoids with rockets on their backs? Or all hoaxes?
Just for the hell of it, yall.