If human eveolved from monkeys, how come ALL monkeys didn't become human?

Question

Ok, apes then, not monkeys. And no god stuff please.

So if Apes and homosapiens have common ancestors, why didn't we all evolved the same?

I'm a science teacher and I believe in evolution so much that I didn't know what to answer to one of my student who asked me that.

Answer 1

Jonmc had it right, but I will try and restate it a little less beligerantly. To put it in a single sentance, individuals don't evolve, segments of populations do.

Let's say a short necked animal has two offspring. One offspring has a long neck due to a random mutation in it's genes. Now it can eat from the tops of trees, while the others still can only eat grass and bushes. These two are NOT competing for the same resource. When they have offspring of their own, these offspring will likewise not be competing with each other. If the environment doesn't change, then in a few years you'll have one species of long necked animals walking around, and a species of short necks. The long necks "came from" the short necks, but there is no reason the short necks should have died out or ceased to exist because of this.

Of course in real life, it's always much more complex than this. Humans actually DID compete with the species that we came from, the earlier genuses of ****, and did replace them. I hope this helps.

Answer 2

Evolution does not say humans evolved from monkeys. It says that Humans and other primates evolved from a common ancestor. Over time that common ancestor further evolved and split into Humans, apes, etc. This happened because that common ancestor spread over the land (most likely the African continent) and became separated from others of its own kind; the species then went on to adapt (evolve) to its current environment leading to the vast array of monkeys that are related to us.

Answer 3

The "humans evolved from monkeys" argument is an inherant misunderstanding of evolutionary theory. Saying humans evolved from monkeys is like saying I'm an ancestor of my first cousin. In reality, my cousin and I have a common relative or ancestor, our grandparents.

Likewise, evolution doesn't say man evolved from present day monkeys, but that man and monkeys have a common ancestor. Just as I developed differently and independantly from my cousin, man and monkeys evolved separately and have different traits. But we also share some traits due to our having the same ancestors.

Answer 4

Based on observations of living populations, as well as the fossil record, most speciation is allopatric, peripatric or parapatric - new species evolve from a geographically isolated, or geographically semi-isolated, sub-set of the larger population. This makes sense logically as the isolated small population will be subject to a different, and concentrated, natural selection. However, splitting in to two species without geographical separation (sympatric speciation) also occurs, eg. through chromosome mutations (like polyploidy in plants) which introduce a breeding barrier, or through exploitation of different food sources etc. In our case, we have 23 chromosome pairs, in contrast to the 24 of apes, and it has recently been shown genetically that one of our chromosome represents a fused version of the two smallest ape chromosomes. Perhaps this is hinting at something that happened back when chimps and us had common ancestors... or maybe it came later. The key thing is that the history of life on earth is a branching bush, not a straight line.

Answer 5

Humans did not evolve from monkeys or apes. We evolved from common ancestors. That said, evolution is not directed. Your question is like asking, "Why didn't all your children become doctors?" Each line evolved down a different path. Some had traits that made them well adapted to different environments. One line (ours) started to learn how to shape it's environment.

Answer 6

What you need to know is that humans didn't evolve from monkeys, that is a common misconception. Primitive Primates evolved into a Group that evolved into Monkeys and another group which evolved into Apes and Humans (essentially apes).

Answer 7

According to the theory of evolution, Humans share a common ancestor with Apes, we didn't evolve from them.

I recommend reading the talkorigins.org archives for info on evolution.

Answer 8

Why, if a mutation occurred within a certain population of animals, would you expect that the same mutation would occur in ALL populations of similar animals? In fact the expectation would be just the opposite. Two distinct populations of monkeys or anything else, over time, would inevitably follow diverging paths of evolutionary change, not the same path, because the mutations which drive such evolutionary change (though they are not the only mechanism involved) are random in nature.

Answer 9

They didn't get the gene mutations responsible for opposable thumbs, frontal lobes or bi-pedalism. Nonetheless, most of our genes are identical. And our ancestors most likely killed off any advanced primates that competed against us for resources.

If evolution didn't exist, there would be no need to continually upgrade and develop new anti-biotics to deal with the continually evolving strains of pathogenic bacteria.

Answer 10

because of genetic variation.otherwise all lifeforms would be the same on earth.it just wouldn 't work .besides they quite likely evolved at the same time ,branching off from a common ancestor.