How did humans evolve through natural selection?

Answer 1

• Modern homo sapiens developed from a species known as homo erectus; erectus was the first hominid to walk upright hence the Latin name. The first appearance of sapiens is around 200 thousand years ago.
• Homo erectus developed from a species named homo habilis, the first hominid to be using tools. The first appearance of erectus was around 1.8 million years ago (or 1.25 mya if you follow the idea that erectus developed from the very similar ergaster, with ergaster being the step between habilis and erectus).
• Homo habilis is believed to have developed from Kenyanthropus platyops. Habilis first appeared between 2.5 and 2 million years ago.
• Platyops is believed by some to be either a member-species of the genus Australopithecus, or to be a misidentification of another extant species afarensis within that genus. Both of these would explain the heritage it has; the specimens found were given their own genus and species in the interim. Kenyanthropus platyops first appeared around 3.5 million years ago.

At this point, the exactness of the human evolutionary tree is disputed; several specimens have been found, the characteristics and times of which complicate the tree somewhat. However, there are at most two or three further ancestors before we reach the most recent common ancestor of chimpanzees and humans 5 to 7 million years ago - it is some interesting research to go back further, and shall be left to the reader if they are interested.

Answer 2

Sort answer: no

Long answer: Only as much as any other species on earth. An interesting philosophical question; in the absence of humans does evolution still exist? This is equivalent to asking 'If we a tree falls in a forest but no one is around to hear it, does it make a sound?' My answer to this would be yes! It absolutely makes a sound. On that note, it makes sense that the process of evolution would continue unchanged in the absence of humans. So no, humans have no influence on the process of evolution because species would continue to evolve even if humans did not exist.

On another note, humans are most definitely having an influence on Charles Darwin's proposed theory of evolution by means of natural selection. Here I must clarify that 'Evolution' and Darwin's proposed 'theory of evolution by natural selection' are different things. Sometimes people get confused and think that evolution is a theory but evolution has been proved beyond doubt, it is a fact that species evolve. While Darwin's 'theory of evolution by means of natural selection' is just a possible explanation for the process by which evolution takes place. Keep in mind that Darwin first proposed this theory in 1859 and it it is designed to explain the process of evolution in nature where it holds true even under the most rigorous attempts to disprove it. In this theory Darwin proposes that 'natural selection' is the mechanism by which evolution functions. Natural selection is a change in the allele frequencies of a species which allows that species to better survive in it's environment. For example, a member of a species is born with a random mutation which allows it to survive better in it's environment than the other members of it's species. This individual has a better chance to reproduce and pass that genetic material on to it's offspring who in turn will also be better suited to survive in their environment. Natural section just means that the members of the species with the beneficial mutation are more likely to reproduce and pass on that genetic material to their offspring. Eventually a percentage of the population of the species will have these genes, we call percentage the allele frequency of the species. Sometimes it is not the genes themselves that mutate but the environment which changes. For example, a change in the environment could occur which would render the mutated members of our spices unable to reproduce. The absence of this portion of the population would allow the rest of the species to thrive.

With recent advances in technology we find that members of our species which ordinarily would be unable to survive can now survive and even flourish in the environment. These technological advances also allow us to manipulate our environment in order introduce members of our species to places where they would ordinarily be unable to survive. Our ability to manipulate the environment allows us to survive in the harshest conditions, for example space. Technology has allowed humans to create comfortable artificial environments in areas which would otherwise promote death in seconds.

These advancements in technology also bring about advancements in medicine which in turn promote the survival of members of our species who would not ordinarily survive. Medicine even allows some of these people to reproduce and live normal lives. In some cases medicine provides an advantage people with genetic mutations which would ordinarily cause them to be unable to compete with the rest of the population.

We find that natural selection is no longer applicable to humans since superior genetic information no longer provides enhanced survivability. Our ability to manipulate our environment enables us to survive comfortably in even the most extreme conditions. However, this does not mean that we've stopped evolving since our genetic information still continues to change from generation to generation. It simply means that natural selection is no longer an acceptable explanation to describe the way humans evolve. Natural selection is however, still a very acceptable explanation for the way evolution works in nature.

Answer 3

Charles Darwin once again surprised the whole world of his book entitled "The Descent Man," which reveals that man and the highest form of primate came from the same ancestor. That man started to evolved from Dryopithecus (40 million years ago) to Homo sapiens sapiens (35 thousand years ago).

Answer 4

All life forms over time change. Genetic mutation is a term typically associated with this kind of change. Mutation does not always mean something bad. It simply means it is not in it's original form. On a geological time scale measured in millions or even billions of years, mutations will abound in all species. Some will be good for the species and it will thrive, others will not and the species will go extinct. The term natural selection is really quite simple. It is natural for a mutation that helps a species, to be selected as one that will continue in future generations. Conversely, if a mutation hinders a species it is natural the species will suffer and perhaps go extinct if it can not adapt. Survival of the fittest is another way to describe natural selection. The mutation that changed the shape of our skull is what led to human beings becoming the dominant life form on earth. This change in the shape of the skull allowed our brains to develop unlike anything else ever had and so, here we are.

Answer 5

It is not fully known in which ways man evolved to become the current Homo Erectus, as not all species were fossilized, and fossil records have not been found for those that were fossilized.

See related questions for a possible fossil hypothesis of how man evolved.

Answer 6

Yes. All the evidence seems to indicate that humans evolved from prior species of ape.