Humans Still Evolving?I Looked at the answer bar but none of those questions have good answers!?

Question

What are scientistr think humans are evolving into?I ask this because I heard somewhere that humans might be evolving into giants not in the width in height.

If there are any scientists out there on Yahoo! answers please help me with this question!

Answer 1

We will never know the answer to this question until it happens. Initially it will manifest itself as a mutation in our genes, perhaps allowing us to breathe polluted air or something else thats gives humans a survival edge, after all that's what evolution is all about...surviving.

Answer 2

Well, if you're really wondering if humans might evolve into giants, we can pretty much put that idea to rest. Not that it couldn't happen...but it is unlikely enough that it practically couldn't happen. If you look at humans now who are born either very large or very small, they tend to suffer from various conditions arising from their sizes. Some of these people actually do suffer from disorders that cause their extreme size differences, but some don't.

The simple fact of the matter is that large, huge, enormous changes must take place in basic human anatomy before we can ever grow into the realm of giants. Even the largest person ever recorded was barely twice as large as the average person, and people who get that large end up so heavy their own bones can't support their weight. Their are no automatic mechanisms in the body for dealing with it. Aside from weight, such a person would have other difficulties that the current human body isn't equipped to deal with.

Stress on the heart would be extreme. A new, larger or stronger heart would be needed.
Blood pressure would be a huge concern. The body would have to deal with that.
As stated before, weight increases exponentially as the body gets further away from average height. Bones and musculature would need to be reinforced.

Again, not that this couldn't happen. Elephants evolved from smaller mammals. It's just that there is no real environmental stress that might direct us to evolve that way. Huge people don't have some overwhelming advantage that the rest of us don't. Quite the opposite in many cases.

While it is true that the size of the average human has steadily increased over the last couple hundred years, this is not the result of environmental pressures directing large scale evolution. It is more the product of increased nutrition, and is more an example of plasticity than true adaptation.

Answer 3

You do not seem to have a grasp of what evolution is. There is no "goal" or "progress" in evolution, so there is no way to predict long term changes. Here is the principle of evolution in a nut shell.

1) there is variation in a population (hair color, strength, etc) and this variation is passed on through reproduction
2) Some outside agent affects mortality/reproduction relative to the variation (faster prey individuals outrun the predator)
3) Over generational time the successful variant become the dominant form in a population as the less successful variant fails to have children (or at least as many)

Heres the catch, the outside selecting agent is always changing (be it predators that are also evolving, climate change, etc) so a successful variant in one situation may end up being deleterious in a succeding situation. It can get rather complicated but the end result is that predicting future evolutionary changes is really a waste of time, since the selecting agents cannot be held as a constant.


On the other hand, physics will tell you that humans cannot "evolve" into giants due to the limitations of our circulatory system as well as issues of foot surface area relative to mass. The only way horses etc can pump blood is by having a little manual pump in their hooves that pushes the blood back up the legs (one reason they sleep standing up). Gravity works against us in both cases. But in low gravity situations (see, changing the environmental parameters and, hence, the selecting agents, this could be different if giant stature confered a reproductive or survival advantage (easier to harvest food, etc).


In response to the above post, it is generally true that height has increased among agricultural populations over the past 200 years but not among hunter-gatherers. This further suggests that nutrition (dependence on a nutritionally incomplete stable) is the limiting factor and that broad spectrum diets (which tend to be nutritionally well balanced) are more likely to result in taller people. Oversimplified, yes, but generally true.

Answer 4

People are still evolving. We are probably not turning into giants, but just getting better nourished. We evolve when some of us die due to disease. The remaining population is more resistant. Evolution can work with miniscule advantages and it can be shown mathmatically how an inherited characteristic with a very small percentage advantage will eventually lead to everyone in the population having that particular characteristic.

Answer 5

Are you not evolved from what you were before you were born? And will you not evolve into a dead thing someday. That is one way you are evolving. If that is not enough why not look at the forms of life we have now compared to a hundred years ago when man still had trouble changing from the dependence on animal transportation. Could they have known you would be a couch potato and make your money with a small machine you carry around called a computer.

Answer 6

Every species on the planet is constantly evolving. Evolution is a continuous process. It never stops. Yes, human are getting larger, but there is still no way to predict what we will become.

Answer 7

Look to Booze Hound's answer. He has a good grasp on evolutionary theory. Evolution can tell you about the past and the present, but does not predict the future. You can not predict the beneficial mutation and environmental change combination leading to natural selection. Now, evolution goes on all the time. Evolution is the change in allele frequencies over time in a population.

Answer 8

Well, natural selection is constantly acting on organisms. Humans just tend to cancel most of it out with technology and innovations. The gene pools are getting very mixed as people from many different countries are meeting and marrying, also. That could have something to do with our "evolution." I can say with relative certainty that we will not become particularly different from our current physical state for many millenia, if our species survives that long.

Answer 9

Many species, horseshoe crabs (same since about 250million years ago), sharks(same for 100million years, very little changed in 350 million years and lions(same for nearly 800,000 years and largely unchanged for 3.5million), to name a few, are so well adapted to their niche that they have pretty much been stable for a very long time.

While some cosmetic characteristics of humans may change, it is unlikely we will ever become unable to interbreed with other humans, unless we find people going out to space colonies and being alone for 300,000 years or so.

Answer 10

Evolution to my opinion never stops. I don't believe that evolution says, well, I reached this stage and that is where I'll stop. Why should anyone disbelief that humans are evolving into giants, one thing is certain and that is that the human brain is getting larger and that we are getting taller from century to century.

Answer 11

The need to have wisdom molars pulled to make room for a normal mouthful of teeth because our jaws are smaller, and the prevalence of lower back difficulties in humans from not being bipedal long enough are two big indicators to me that we're not done yet.