what is human evolution? if all humans come from africa then why we are so different?

Answer 1

Because evolution is an ongoing process. We did not evolve in Africa and then spread out. Humans spread out from Africa and kept evolving, developing traits that suited their new locations.

The fact that there are different types of humans is a strong argument for evolution. The traits that make up the different "races" can be traced by to adapting to different environments. People who developed in hotter climates that have an abundance of food will be different that people who developed in a cooler climate where the food abundance was seasonal.


OK, big oops on my part. I did not answer your initial question.

Human evolution is humans evolving from other forms of life or even from other forms of humans. The evolution can trace back to small ape like creatures millions of years ago. These creatures experienced random mutations, just like we do today. Most of these mutations were not noticeable and had no effect. Some hindered the creature and some helped the creature. Lets say that the mutation made the arms a little longer than the others and the creature could reach higher into trees to get food. Now, that creature has a better chance of getting food and therefore has a better chance of surviving. It was the genetic lottery. With a better chance of surviving, there is a better chance of mating. That means a better chance of passing along the mutation that allowed for the longer arms. In time there are many of these creatures with the slightly longer arms. This process repeats itself and over time you will have a different set of creatures that have longer arms. The original group might still be around, especially if there was a different group of them evolving elsewhere. These successful mutations and then selective breeding capitalizing on these successful mutations allow the creatures to change over time and with enough time you will get new species.

Ok, human evolution involves this apelike creature. It evolved over the millions of years into various species. The evolutional chain branched several times so that today there are many different types of species from that one type in the beginning. Man and apes are descendents from that one species.

This same process can allow for different types of humans to exist. They migrated. Some stayed where they originated. You now have the same species in different areas and with different environmental demands. The groups are also isolated so that they will each get different mutations. They will evolve along different paths and over the years you will start to notice differences between the two groups. Usually, these differences give some sort of advantage for where they are living.

Answer 2

Wow, the correct answer to this question is long and drawn out that I just don't have time for it. The short answer is, we're different because we need to be. We evolved to be Asian, black, Indian, white and the other colors of the rainbow because of many different factors and reasons. A large part of the reason for our evolution is the different environments we found ourselves living in over the hundreds of thousands of years. I suggest you study it on your own, there are thousands of great books and journals out there, take a look and decide for yourself why we are the way we are.