how did human evolved and how are we so sure we really did??

Answer 1

You are asking two *very* long questions.

The first question is long because there are *many* reasons why we evolved, and second because you don't specify how far back in evolution you are asking about.

The second question is about the *evidence* for human evolution ... and this is a loooong answer because there's a LOT of evidence.

Most people know about fossils. These are rock impessions of the skeletal remains of long-extinct species. We find these in deeper and deeper layers of rock. We can date these layers, and thus these fossils, to be older and older in time. And, as we look at older and older fossils, the structures of these skeletons look less and less like modern humans and have more and more features in common with other primates (like a smaller brain case, a larger forehead and jaw, hips and back that show less of an upright position, longer arms, etc.)

But fossils aren't even close to the only evidence. In fact, even if not a single fossil of *any* species had ever been found ... the evidence for evolution, including human evolution, is pretty overwhelming.

Besides fossils there's:

1. Anthropology/archaeology evidence (tools, mummified remains, cave paintings, etc. showing where on the planet humans started appearing and migrating ... and when).

2. Genetic evidence. (Genes in common with other living species.)

3. Molecular evidence. (DNA ... most of it not involved in genes ... and yet still in common with other living species.)

4. Proteins. (Again, letter-for-letter similarities and differences between related species.)

5. Vestigial structures. (Structures we have that have no function or a reduced function ... like the appendix, the plantaris muscle, or your big toe.)

6. Homologous structures. (Structures shared with other mammals and even with reptiles ... where the specific structure ... such as the number of bones in the hand vs. in a bat's wing or a horse's leg ... are the same despite *radically* different function.)

7. Embryology. (Structures that appear and disappear during development of the embryo ... such as the tail, gill folds, or webbed fingers ... all evidence of more genes inherited from ancestors for which these were useful.) Sometimes these lead to 'atavisms' ... babies born with a small tail, or webbed fingers or toes.

And lots more. In my answer to the following question, I go into these in more detail:
http://answers.yahoo.com/question/index;_ylt=AgkOsCfRl1IzQPICyICEiJ3ty6IX;_ylv=3?qid=20060916192539AAlVbL4

Answer 2

Well for starters, there is significant fossil evidence showing the gradual evolution of of all species, including people.

Also in the age of DNA, we are able to compare human DNA to other species and not surprisingly apes have DNA that resembles ours far closer than say a fruit fly.

Now many people that argue against evolution have an agenda to defend their religious beliefs. This is not new, Galileo was put to thumb screws when he proposed that the earth orbited the sun and was excommunicated from the church (which was not lifted until the late 1990's).

As to "How we evolved?" ... well that my friend is a very long long long story. The "modern human" evolved some 120,000 to 60,000 years ago (depends on who you ask). And for people that live at the most to about 100 years, it can be hard to wrap your head around how long that is, but you can think of it kinda like this the first modern human would have been your great (x 2400) grand parents. Considering that your great (x80) grand parents where around during Julius Caesar's time ... it is a long time.

Answer 3

Humans have evolved in the same way that every other organism on earth has evolved--natural selection. If you want to understand evolution and what it says and means and what it doesn't say, you might check out http://www.talkorigins.org .

The amount of evidence to support the fact of evolution is overwhelming and comes from many different kinds of observations and experiments in every different area of biology. There is absolutely no scientific evidence that contradicts evolution as an explanation for the origins of humans and all other organisms.

Answer 4

"How" humans evolved is a strange sort of question - "in the usual way" is my answer. It's essentially impossible for a species to exist for any length of time and NOT undergo evolution. The continual process of mutations and their fixation in the population ensures that any species will evolve. How are we sure we really did? Well, you can trace the genetic evidence pretty clearly. Just compare human genome sequence to chimpanzee genome sequence to see where our genome evolved. Or compare within the human population to see specific instances of ongoing evolution.

Answer 5

we didnt we have been adapting by growing taller or stronger but we have no hard evidence that any species has mutated since humans have been able to bare witness. evolution is an excuse for scientists who cant live up to the truth. there is a superior power and they cant figure out how it works so they created the theory of evolution. there is more evidence proving it false then true

Answer 6

Hi. Well, you are here to ask the question but the Neanderthals are not. 'Nuff said?

Answer 7

We're more sure about some than others.