# How much would humans and animals evolve in 10 thousand years?



## nwillmott8897 (May 28, 2013)

my current WIP is set 10 thousand years in the future, in a world where humans do not have any access to technology because of events you can find out about here: http://mythicscribes.com/forums/world-building/8601-does-background-make-sense-implausible.html So any evolving humanity would do would be to survive against animals that have also evolved to the tough environment my world is set in. 

I was planning on only changing humans slightly, by making them slightly shorter and more agile. But I'm not quite sure if humanity would evolve even more than this, or not even this much. As you can understand, when i tried to Google this I got pages speculating about how we would evolve around our technology, which is no help for my research.

Even if you cannot be scientifically correct, _please_ leave your input... 
How would you evolve humanity?
Do you like my idea?
Could you suggest anything more I could do to evolve humanity?

Thank you so much in advance,
Nathan.


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## Penpilot (May 28, 2013)

Based on my limited first year biology understanding, it depends. Evolution is a response to our change in environment. Environment tends to change slowly so evolutionary change is slow. If environmental change out races evolution/our ability to adapt then that's when we get extinction.  

The faster the reproductive cycle, the quicker the species can adapt. Mayflies have a super quick reproductive cycle so they're used in genetic research.  

As for how fast a human can evolve? It depends on how hard environmental factors are pushing without driving humans to extinction. 

A very simplistic example. Let's say a disease with 100% mortality runs through the population killing everyone except those with blue eyes. Let's say the disease persists and anyone born without blue eyes dies. In a relatively short span of time, the human species will have evolved through natural selection to only have blue eyes.

Now let's lessen the environmental pressure. Let's say the mortality rate is say 75%. Now the population will trend towards being more and more blue eyed, but it will be slower and it will never be 100%.

You can apply these examples to any sort of trait, height, speed, etc.

If you're really interested, I'd suggest reading up on how evolution through natural selection works, not just on humans. It's actually quite simple and can apply to more than just  biology. Check out the wikipedia page on Natural Selection. That's a decent enough place to start.


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## Telcontar (May 28, 2013)

Biologically, human beings are not likely to change much over ten thousand years. From what I recall we have existed in roughly modern form (again, biologically speaking) for the last 50,000 years.

My question is: Why worry about a comparison to modern humans? 10k years in the future after a supernaturally-caused catastrophe it doesn't seem that there would be any basis for the comparison to be brought to the readers attention. If you simply want to have your characters regularly undertaking feats that humans realistically couldn't do - just go right ahead and do it. Fiction of all kinds regularly disregards the real limits of human performance in favor of a good scene.

If you really wanted them changed in some fashion, why not simply suggest that whatever magic these demons used to cause the catastrophe also promoted a change in various worldwide species?


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## A. E. Lowan (May 28, 2013)

Evolve?  Not much.  We as a species have not evolved at all in the past 10k years, from hunter gatherers to city dwellers.  However, that being said, we have _adapted_.  A richer food supply has extended our lifespans, made us taller, more muscular, and, recently, fatter.  So, yes, it is plausible that your humans can be shorter and more agile, but this is environmental influence, not evolution.

I would expect, in the scenario that you present, that human lifespans would be shorter.  For most of our history, we faced and average of 35 years, taking into account very high infant mortality rates.  You would also need to take into account high mortality rates due to infection and disease, unless your population retains the technology to manufacture simple antibiotics and remembers to wash their hands.  It's amazing how many women historically died in childbirth not due to complications, but due to the fact that no one knew to wash their hands.  Childbirth was the #1 killer of women for centuries.

Your people would themselves be shorter, as well, due to limited nutrition, unless you have them eating well in a post-apocalyptic environment.  Who knows?  Volcanic soil is awesome fertile!   Nutrition plays a huge determining factor in development, a fact that can been seen today by the simple expedient of comparing average heights between inner city school children and their wealthier suburban counterparts.  As a former substitute teacher, I have observed this first-hand.  My inner city kids were, as a general rule, a few inches shorter than children in the suburbs of comparable ages.  Two different school districts = a difference of 2 - 3 inches in height.  The difference?  The shorter kids were not eating at home.  Their only meals were served at school, and at home and on the weekends they scrounged or starved.  The long term effects are devastating.

Agility... that will depend on environment.  Do your people need to be agile to get around?  To survive in a hostile environment?  If so, then yes, they will become more agile.  Humans are extremely adaptive, changing our behaviors, skills, technology and conditioning to successfully inhabit all 7 continents on our planet.  We can adapt to anything.

You said you're having a hard time researching this topic.  Have you researched post-apocalyptic speculation theory, or just human evolution?  Human evolution theory tends to go forward based on the assumption that there is no apocalypse.  An apocalypse would result in human _devolution_, so theories of evolution do not apply.


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## Saigonnus (May 28, 2013)

Like as said above, I don't believe humans would evolve that quickly in such a short time geologically speaking; which normally takes hundreds of thousands if not millions of years. We have changed a bit over in that time frame though; for example, I read an interesting article about how we have a higher chance or devoloping things like allergies or lactose intolerance now then any other time in our history, and it likely stems from processing (pasteurization) we've done to milk for a couple centuries now and the increased chance a mom isn't breast feeding her child with the availability of formula and bottles. That is simply one aspect of changing due to environmental factors. Physiologically, we haven't changed at all except in little ways like I listed above in the past 10,000 years. 

If your humans are shorter, that could simply be a response to a low protein diet (like seafood, rice etc.) and not necessarily a genetic evolution. I worked with a Vietnamese guy who moved to the US in his teens (his development had already stopped), but his kids were born and raised in the states. He is perhaps 65 inches tall (5 foot 5) but his sons are both over 6 feet tall from having a good diet growing up.


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## Penpilot (May 28, 2013)

aelowan said:


> Human evolution theory tends to go forward based on the assumption that there is no apocalypse.  An apocalypse would result in human _devolution_, so theories of evolution do not apply.



Can I ask where you get this information. I googled post-apocalyptic speculation theory and I get nothing. From my understanding there evolutionary theory makes no such assumption about apocalypse or no apocalypse. And I don't see how evolutionary theory would ever stop applying.

Back to the original topic. I just remembered something that can help. It's call Punctuatied Equilibrium. https://en.wikipedia.org/wiki/Punctuated_equilibrium Basically it says that for the most part evolution is slow and steady but then there are points where there will be a jump and rapid speciation (one species evolving into many) in a short period of time will occur. There are flaws in the theory but...


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