At the beginning when there was just Adam and Eve, i know they had kids but if they were the only ones than how did there get to be so many people on the earth? And if there was only them at first then how come people are so different? Some people are super tall and some people are super tiny, how did it happen?
This is just some other silly question but Neanderthals never existed right? If they didn't then how did the idea come up? Was it just some big hairy guy that was actually from Bible times?
To answer your question, let's use a human population calculator. The current growth rate is 1.2%. Let's assume that back then it was 0.9%. that would be a child every 50 years or so. In 1,650 years (the time from the creation to the flood), there would be 5,218,709 people in the world! This would not include mass deaths, such as from wars or disease, but you can see that it doesn't take long for human beings to populate the world.
Everything God created is a blend of a wide variety of characteristics. if you interbreed the whole population, it would remain mostly the same, but as soon as small groups become isolated from the general population, then certain characteristics will become dominate. Animal breeders do this all the time to get, say different characteristics in a breed of dogs. So, it isn't surprising that it can happen in the human population where geography isolates groups of people.
What are called Neanderthals today is a set of bones found in Europe. These have been put together and then artists guess from the skeleton that the person might have looked like when alive. So where did the hair come from? Some artist decided that they must have looked hairy because that would be more "primitive." After all the scientist told the artists that these people were closely related to apes and apes are hairy. In other words, it is all made up in people's imaginations.
Evidence exists that Neanderthals are merely variations of the typical human being [Brian Thomas, "Neanderthals were Modern Men," ICR]. They are now considered an ethnic group [John D. Morris, "Is Neanderthal In Our Family Tree?" ICR]. More current reconstruction of what a Neanderthal might look like shows people whom you could probably pass on the street and not notice any differences.
Okay I sort of get it. But I am still a little confused because I guess what I was trying to ask was, if at first there was just Adam and Eve and they had two kids, then how did more people get born?
And you said that if everyone on earth was in one spot they would look mostly the same but if some people went somewhere else in the world they would start to look different?! I'm still kind of confused about this, why would people change how they look if they went somewhere else?
Because Adam and Eve didn't just have two children. We know the names of three of their sons, but we don't know the names of all their children, or even how many children they had. "After he begot Seth, the days of Adam were eight hundred years; and he had sons and daughters" (Genesis 5:4). One could have a lot of children in 800 years.
Let's assume that skin color is controlled by a single gene, B, (it isn't but it makes the illustration easier). People have a pair of every gene, so if someone has BB they will be dark skinned, if they have Bb or bB they will be a midrange color, and if they have bb, they will be light skinned.
If Adam and Eve both had Bb genes then they would have been midrange in color. On average 25% of their children would be BB (dark), 50% (midrange), and 25% would be bb (light). These children would intermarry and unless some married those of the same skin tone, the majority of the grandchildren would be the mixed Bb (midrange) tones. This would continue through history.
But suppose several of the dark skin toned children moved away so they did not have contact with the rest. The result would eventually be a large group of dark skin toned people because there would not have been any light skin tone genes to keep a balance. Thus, isolating a group makes the current features of the group dominant.