This is one of many questions that science can't explain, some say human evolved from ape, but there is a missing link in fossil history, so that can't be true. As far as i know, humans are about 30000-40000 years old (on earth), but where did they come from .. just out of the blue?
There are some theories:
1. some say god made humans - i think this is lame and ignorant, people who say that have very low IQ and are generally ignoring the facts of existance, however that depends how you define "god"
2. some scientists say that humans were formed randomly, by a chance, where particles just formed together, but there are billions and billions of combinations .. so in other words, even in like 1000000000 billion years it could not happen, what are the chances right? but its POSSIBLE!
just like in one of the old NEC games (one of the first game consoles) you had to enter a long savegame code (those consoles had no storage, only way to "save" game was to enter a long code), and in one of those games i entered a random code and it was valid, those codes where like 20 - 40 digit .. what are the chances right? just saying .. its possible.
3. more complex theory, is that humans "walked" in from another dimension, thru a portal (gateway, wormhole ..whatever you call it), but thing is with this theory, lets say its true .. then what? it would still not explain where humans came from, it would only explain how humans got onto planet earth.
4. Earth is actually a test site for some superior being, like some race of aliens made us, very possible, because humans make stuff too, cross genetics and stuff like this and its all being done in a lab, maybe earth is somebody's lab, very possible, i mean .. why else aliens visit earth time to time?
In my personal opinion, i tend to think that aliens made humans (or dropped humans on earth) and that earth is alien test site / lab. anyone who doesn't have head under the sand, knows that aliens have visited earth many, many times and that there is proof. This would also explain the people who belive in god, god and aliens are same thing. whatever made humans, they call it god, i call it aliens...whats the difference right?
It all makes sense to be honest, aliens made life on earth, then they dropped in the superior predator (human) and wanted to see what happens, if fragile, but intelligent lifeform like human would survive or get eaten by wild animals.
Also if this is true .. then what if they drop in another, more superior lifeform? would they make us, the humans their slaves?
Actually all this makes me think about the Predator and Alien movies, i think there is lot of truth in them.
For example .. look back in human history, at the time where god was taken VERY seriously and people killed the ones who did not belive in god, in those times, humans imagined gods as humans with animal heads, hmm...kind a like in predator movies, right? that doesn't mean those "things" created humans, maybe they used humans to get some simple work done, for example how were pyramids made? yet another question that no1 really has answer to, but i think that aliens surely visited earth and made humans do stuff, like build pyramids, but they made sure that human race will not have any evidence of them .. but again there are pictures carved into rocks and those statues of humans with animal heads (like predator like creatures).
Also those stories of alien adoptions make me think that they keep eye on humans to see how their test project is doing, i mean clearly thousands and thousands of people can't be wrong about aliens, im sure lot of them make it all up just to be famous, like those fake videos .. etc, but there are also cases where science can't prove it was faked. I think that back in the days more people told the truth, because nowdays it is all about videos and air-time (radio, tv..etc) and finally it all comes down to money! because they make lot of money out of it once their story sells, but back in the days, like 50s, 60s..etc there was no such thing, so there was no reason to lie about those things.
anyway, what is your opinion, what you think where did humans come from?