Are human actions part of evolution?

In summary, the conversation revolves around human activities and their impact on the environment and other species. The speaker argues that these actions are a part of evolution, as they are a result of inherited traits like selfishness. The other person argues that humans should be held responsible for their actions, and that human nature is subject to modification by cultural and environmental forces. Ultimately, it is agreed that these activities are a factor in evolution, and that humans should consider the consequences of their actions.
  • #1
Snip3r
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Me and my friend were talking about human activities. She said that humans are creating pollution, killing so many animals creating an imbalance in food chain, global warming etc. In short we are making it worse for ourselves and other species. My reply was whatever humans do is a part of evolution (like we inherited the traits like selfishness to do these things and there is really not much we can do about it) and humans are not doing anything worse. Our actions may affect the evolution of ourselves and other species which is a different story. Is my argument correct?
 
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  • #2
Offhand I would agree with you. I find it very interesting (and not entirely unjustified) that we usually separate nature from ourselves. If one of the things evolution has done is to increase the intelligence of a species, it does make sense, at least to me, that whatever that species does with their intelligence could be considered a part of evolution in some manner.

However I have to admit that I have only a small amount of knowledge about evolution, so don't take my opinion as anything close to fact.
 
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  • #3
One would think that HBs inherited a drive to reproduce. Nevertheless contraceptives were developed and are widely used.

While HBs may not be "doing anything worse" it seems not too much to ask for humans to show more foresight as to consequences than is shown by bacteria.

To put it bluntly, "inherited traits" is a poor excuse for wanton destruction. I personally don't feel compelled or even inclined to do any such thing.

By the way, wolves limit their reproduction rather more severely than do human beings, so such restraint is not unique. I would hope that humans would be able to show self-control at least equal to that practiced by wolves.
 
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  • #4
Hornbein said:
To put it bluntly, "inherited traits" is a poor excuse for wanton destruction. I personally don't feel compelled or even inclined to do any such thing.
How is that an excuse? These traits might be more severe in those who do the destruction and you may not be inclined to do such things because your genes may not carry these traits. The population which is able to outlive and reproduce is going to spread those specific characteristics to its offspring. For the sake of argument, if most humans today are egocentric, would mean that selfishness is more successful in propagating itself to a species' offspring than altruism is. However whether this ecosystem would survive is a different story.
 
  • #5
Drakkith said:
I find it very interesting (and not entirely unjustified) that we usually separate nature from ourselves.
Can you tell me how it can be justified if not entirely unjustified?
 
  • #6
Snip3r said:
Me and my friend were talking about human activities. She said that humans are creating pollution, killing so many animals creating an imbalance in food chain, global warming etc. In short we are making it worse for ourselves and other species. My reply was whatever humans do is a part of evolution (like we inherited the traits like selfishness to do these things and there is really not much we can do about it) and humans are not doing anything worse. Our actions may affect the evolution of ourselves and other species which is a different story. Is my argument correct?

I don't think these are mutually exclusive. Organisms have certainly evolved to adapt to changes in the environment caused by human activities. However, many of these changes to the environment are happening at a very rapid pace, making it difficult for many organisms with long generation times to adapt. Extinctions, even mass extinctions, are certainly part of nature, but we should also remember that humans are subject to extinction as well.

Snip3r said:
How is that an excuse? These traits might be more severe in those who do the destruction and you may not be inclined to do such things because your genes may not carry these traits. The population which is able to outlive and reproduce is going to spread those specific characteristics to its offspring. For the sake of argument, if most humans today are egocentric, would mean that selfishness is more successful in propagating itself to a species' offspring than altruism is. However whether this ecosystem would survive is a different story.

Perhaps this goes beyond biology to philosophy, but ultimately individuals and societies should be held responsible for their own actions. Human nature, if it is encoded by genes at all, is certainly subject to modification by cultural and environmental forces, so we should not think of our behavior as something beyond our control.
 
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  • #7
Ygggdrasil said:
I don't think these are mutually exclusive. Organisms have certainly evolved to adapt to changes in the environment caused by human activities. However, many of these changes to the environment are happening at a very rapid pace, making it difficult for many organisms with long generation times to adapt. Extinctions, even mass extinctions, are certainly part of nature, but we should also remember that humans are subject to extinction as well.
Yes, I agree with all the above. But my question is are these activities of humans part of evolution? She was arguing they are not.
Ygggdrasil said:
Perhaps this goes beyond biology to philosophy, but ultimately individuals and societies should be held responsible for their own actions. Human nature, if it is encoded by genes at all, is certainly subject to modification by cultural and environmental forces, so we should not think of our behavior as something beyond our control.
Disregarding those environmental forces which are not under human control, the cultural forces are again from the variety of traits of human genes fighting for survival. isn't it?
 
  • #8
Snip3r said:
My reply was whatever humans do is a part of evolution (like we inherited the traits like selfishness to do these things and there is really not much we can do about it)

I'm not exactly sure what your question is, but perhaps the answer you're looking for is that, yes, everything is a relevant factor when it comes to evolution. Social evolution affects biological evolution and vice-versa. We have evolved a tendency toward selfishness but we have also evolved a sense of altruism and a protest against selfishness also. So there is something you can do about. You don't just have to throw up your hands and resign yourself to prospect that the world going to hell is an inevitability because humans evolved a "selfish gene." You can combat greed and harmful policy with more words and energy in another direction. That's how competition in natural selection works, at all levels.
 
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  • #9
Evolution happens because some organisms adapt to changes in environment while others don't.
It makes no difference to evolution what causes the environment to change. and evolution is not judgemental.
 
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  • #10
Snip3r said:
Disregarding those environmental forces which are not under human control, the cultural forces are again from the variety of traits of human genes fighting for survival. isn't it?

Very few human behaviors are innate. Our brains have evolved such that most of the connections form in response to lived experience and thus our brain wiring comes primarily from learning. Culture is something that societies can control and change.
 
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  • #11
I do not think it's a matter of evolution in any sense of that word, other animals adapted to changes in environment symbiotically with balance and have a purpose, where as humans, "we change the environment" technological advancement for creature comfort and convenience. So if this is evolution what is the purpose? Are we the planets self destruct mechanism?

Just a thought.
 
  • #12
Richard Dawkins in 'The Selfish Gene': the meme is defined as a culturally mediated behavior that is subject to Natural Selection.
E O WiIson in 'Sociobiology' and later in 'Social Conquest of Earth' states studies that support Dawkins, goes beyond what Dawkins has to say, and gives examples of social behaviors that have been and still are being selected for. Humans are hypersocial.

If you have not read these books - please do not make up stuff and post about what a 'meme' is, or how social structures and interactions can be subject to Natural Selection. Please cite something respectable if you want to do that. Those "definitions" I gave are NOT detailed, they are a 10000 foot view. And are meant to advance discussion, not stop it. Example: the two author's positions go counter to several of the above posts, which seem to say that social interactions are not subject to Natural Selection.
 
  • #13
gjonesy said:
I do not think it's a matter of evolution in any sense of that word, other animals adapted to changes in environment symbiotically with balance and have a purpose, where as humans, "we change the environment" technological advancement for creature comfort and convenience. So if this is evolution what is the purpose? Are we the planets self destruct mechanism?

Just a thought.

Human beings are not the only creatures that change their environment. For example, ants can build huge underground colonies by changing their environment (digging their tunnels and nests) to suite their needs. This would obviously be detrimental to many other organisms that already inhabit that part of the soil, such as earthworms and other insects. We also aren't the only organisms to have introduced drastic changes to the entire biosphere, though we are likely the only species to have done it by themselves and over such a short time period. Just look at the oxygen catastrophe 2.3 billion years ago which devastated the obligate anaerobic organisms that existed at the time.

gjonesy said:
other animals adapted to changes in environment symbiotically with balance and have a purpose

I don't think that's correct. Entire species (or higher orders) can become extinct because of a sudden encroachment of another species into their territory, either because the new organism is a predator or because of the increased competition for food and other resources. Organisms also commonly adapt by becoming a parasite.
 
  • #14
To clarify my post, I will say that human cultures and societies are not subject to biological evolution because "human nature" and culture are not encoded genetically. Societies and cultures change over time and it can be useful to think of these changes as occurring through natural selection, but these processes are only analogous to biological evolution as there are a number of important differences (for example, experiences can cause people to change their minds, but not their genes).
 
  • #15
Ygggdrasil said:
To clarify my post, I will say that human cultures and societies are not subject to biological evolution because "human nature" and culture are not encoded genetically. Societies and cultures change over time and it can be useful to think of these changes as occurring through natural selection, but these processes are only analogous to biological evolution as there are a number of important differences (for example, experiences can cause people to change their minds, but not their genes).

Would it be accurate to say that evolution does affect culture and society, but since it acts over a timescale of hundreds of thousands of years its effects in the short term (a few generations at most) are negligible and thus it is rarely considered to have any effect at all? We usually don't talk about changing society over the course of a geological eon after all.
 
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  • #16
Drakkith said:
Would it be accurate to say that evolution does affect culture and society, but since it acts over a timescale of hundreds of thousands of years its effects in the short term (a few generations at most) are negligible and thus it is rarely considered to have any effect at all? We usually don't talk about changing society over the course of a geological eon after all.

Yes, biological evolution is likely not responsible for most cultural and social changes as these occur on too short of a timescale for biological evolution to have an effect. Human biological evolution may be able to explain some cultural and social shifts over geological time periods, though I am not aware of any strong evidence supporting or refuting such claims. Transition from hunter-gatherer to agrarian societies and other such shifts likely caused genetic changes, but to what extent genetic changes enabled such a cultural transition is unclear. Genetic differences likely do not underlie most cultural and social differences between different extant human populations (though some can probably be attributed to genetic changes, such as the prevalence of lactase persistence and the use of dairy in various foods).

Evolution in general, however, does affect culture and society. For example, in Guns, Germs and Steel, Jared Diamond argues that the co-evolution (or lack thereof) between large mammals and humans explains why most domesticated animals came from Europe, why similar animals in Africa cannot be domesticated, and why similar mammals in the Americas were hunted to extinction.
 
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  • #17
I agree that we are just another part of the great evolutionary process and our greed and neurotic behaviours are part and parcel of that bundle. However, we also have the ability to see the error of our ways and the technological abilities to fix it. Hopefully that fix includes all the other animals who have evolved right along side of us. So it's Six of one; a Half-Dozen of the other.
 
  • #18
Drakkith said:
Human beings are not the only creatures that change their environment. For example, ants can build huge underground colonies by changing their environment (digging their tunnels and nests) to suite their needs. This would obviously be detrimental to many other organisms that already inhabit that part of the soil, such as earthworms and other insects. We also aren't the only organisms to have introduced drastic changes to the entire biosphere, though we are likely the only species to have done it by themselves and over such a short time period. Just look at the oxygen catastrophe 2.3 billion years ago which devastated the obligate anaerobic organisms that existed at the time.

I was specifically talking about the unnatural unorganic means by which we as human haven't phyically evolved to adapt...strictly mentally and intellectually speaking, our chemically and electrically powered advancements (heating cooling fossil fuels) have polluted the environment. I understand other creatures create micro climates to help them survive but only humans can boast that we have entered and survived all earthly possible environments and some not so earthly (space)

Drakkith said:
don't think that's correct. Entire species (or higher orders) can become extinct because of a sudden encroachment of another species into their territory, either because the new organism is a predator or because of the increased competition for food and other resources. Organisms also commonly adapt by becoming a parasite.
I also wasnt talking about natural extinction events...in some cases that's just the natural order (natures way). When i say species adapted to an environment with balance and purpose sometimes that includes out performing other creatures naturally. Not killing them for sport or with pollution making the environment uninhabiable. In those cases the encroaching natural even the higer evolved animal may still symbioticly help that environment. Let's say the species was an invading hord of plant eating insects ...they then devistate the plant environment but let's say there are a few insect eating frogs and bats and birds in the area...now food is abundant their numbers increase the insects decrease which then draws the preditory animals that feed on frogs bats and birds...it balances the wheels on the bus tha go round and round. Our preditors are disease and each other. And we as a species are constantly finding ways to try and defeat these problems and usually we create more then we solve...thats all I am saying.
 
  • #19
gjonesy said:
I was specifically talking about the unnatural unorganic means by which we as human haven't phyically evolved to adapt.

So when an organism moves earth, stones, and wood around to build a shelter from the environment and predators it doesn't count as "unnatural"? Beavers cut down trees and build dams to protect themselves. Is that so different from me building a house? The method is certainly different. Evolution didn't endow me with strong teeth and jaws by which to chew down a tree. But it did endow me, and the rest of our species, with a brain and the intelligence to gradually develop complex societies and technology, through which I am now able to build a house.

gjonesy said:
I also wasnt talking about natural extinction events...in some cases that's just the natural order (natures way).

One could argue that our actions are merely "natures way". Imagine if an alien species, a million years further along in evolution and technology, visited our planet. Would they look down upon us as we look down upon a gibbon or a lemur? Would our actions be attributed to "natures way"? Or would they hold us accountable and as being "above nature"? I certainly don't have an answer for that, but I think it's interesting to think about.
gjonesy said:
...thats all I am saying.

I think you've created an arbitrary distinction between humans and other creatures. As you've stated it, it pretty much couldn't be any other way, as no other species has the ability to create and use technology more complicated than a stick. And most can't even do that. But the question is, what does evolution have to do with all of this? My stance is that since human beings are a product of evolution in the first place, our actions are just as much of a product of evolution as a peacock's colorful tail and mating dance are. But we also uniquely possesses the intelligence to understand the consequences of our actions and the effect we have on the environment, which is also a product of evolution. With that comes the ability to judge ourselves and our actions and decide what is good and what is bad.

But, again, I'm not a biologist or philosopher, so I might be talking a bunch of nonsense here. As always, someone correct me if I'm wrong.

Ygggdrasil said:
Evolution in general, however, does affect culture and society. For example, in Guns, Germs and Steel, Jared Diamond argues that the co-evolution (or lack thereof) between large mammals and humans explains why most domesticated animals came from Europe, why similar animals in Africa cannot be domesticated, and why similar mammals in the Americas were hunted to extinction.

I just ordered that book off of Amazon. Thanks for telling me about it!
 
  • #20
I think there are some misconceptions here based on what is commonly called the naturalistic fallacy. In reality the natural world is neither "balanced" or nice or purposeful. Animals and plants regularly pollute their environment, if you think about it that's how wine is made, plants are masters of chemical warfare, probably much better than we are, animals do kill for fun and many animals live short brutal lives characterised by fear, long periods of hunger and an early painful death. When humans take animals into captivity it almost immediately doubles their lifespan ( a very rough average). Evolution has provided us with a range of abilities that have allowed us to spread across the world, live in most environments, reduce hunger and disease and reduce many of the natural risks of living. We are probably the most social animal on the planet, which has played a massive role in our success but I suspect our greatest abilities are in language, flexibility, and the ability to pass on information all of which link to human culture. I think we like feeling so important and powerful that everything that happens is as a result of our actions but remember that the Earth changes whether we are here or not. 99% of every species that has ever existed are now extinct, very few had anything to do with us. You could think of humanity from a non human viewpoint, perhaps we are the product of the plant wheat, an insignificant plant from the middle east that with a small evolutionary twist became such an important food source to us that it now dominates the entire globe, or maybe grasses generally, we look after most of them.
People seem to like feeling guilty it provides a back handed compliment to ourselves, the idea of a human caused extinction event is a case in point, we have little idea of the number of species on the planet, there are hundreds classified every year but we do know that there are more species on the planet now than at any time in history. We certainly introduced new species to island populations in the age of exploration but you might want to think about how many species you can name that have become extinct in recent history and how many have benefited from human interventions, I think you might be more successful with the second question.
 
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  • #21
Drakkith said:
But, again, I'm not a biologist or philosopher, so I might be talking a bunch of nonsense here. As always, someone correct me if I'm wrong.

No its not nonsense, its actually just a different view of what's going on and its process. From my understanding Homo sapiens have had the same capacity for learning since modern man started this journey. And although I would guess as our abilities, adaptation and intelligence evolved the need for our physical bodies have not and that is a direct reflection of our curiosity for discovery and our ingenuity. We have made life far more easy then it was ever meant to be. In fact humans now may be significantly naturally weaker then our distant ancestors. And in the process the byproducts of that ingenuity has tipped the balance, land fills, modern plastics that aren't biodegradable air and water pollution. I once read an article that said there was a trash Island floating in the ocean that was the size of Rhode Island. None of this can be good for us can it? The environment, the air, the ground? I love tech, TV fast food and modern medical as much as anyone. But barring a major thermal nuclear war, I think eventually our advancements and the pollution that comes with it will eventually be our destruction.

Basically what I am getting at is if we could turn back the clock say 400 years, where man lived by his knowledge of the land and road beast of burden and our natural predators were still large animals disease and circumstance, and we stayed that way till now, we most likely would have evolved immunity to most common bacterial and viral diseases, there would be far less pollution and the population would be in check. Cancer would probably be the odd occurrence as would most food born and chemically born diseases. My personal opinion is irrelevant to most others with the exception of some native American groups. I have read some resent studies that people eating whole food diets, natural and organic, with food intake restrictions are far more resilient and healthy then most others. There was a story I read about an Indian guru that ran the Boston marathon at age 83, his secret was that he ate only 4 meals a week of only whole food and rarely any meat. Take for example some Centenarian, Okinawa Japan has more per capita population then any other place on earth. If I remember correctly when reading an article about the subject, one was asked why he though people were dying younger now a days and his reply was, they have abandon the old ways. If we lived like our ancestors we would only eat what we could gather find fish hunt or kill. Which means we wouldn't be eating very much nor would it contain the chemicals or hormones processed preserved foods do today.

http://www.okicent.org/
http://www.okicent.org/study.html
 
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  • #22
Laroxe said:
animals do kill for fun and many animals live short brutal lives characterised by fear, long periods of hunger and an early painful death.

In some cases theses "animals that kill for fun" are just domesticated animals that kill because of instinctual triggers, domestic cats hunt and kill small animals and "play" with them because its a natural hunting instinct that they no longer have to employ to survive. They see movement the pray runs it triggers a predatory response. Why eat the rat you just killed if you have a can of fancy feast waiting at home for ya? Things like that can be thought of as a direct result of mans interference with the natural world. Also wild animals that kill (apparently for no reason) like the bottle nose dolphin are thought to be committing acts of cruelty against other species of dolphins...BUT when you think about it is killing them for fun or are they eliminating and driving off competitors for food and territory, given that dolphins not only compete with each other but other sea mammals including us. I have read and heard of wild animals killing other animals but is it born of sport? Or is an instinctual response or need do to habitat lose, competition, territory or other reason unknown. Its not like you can sit the animal down with a therapist and ask it why it felt the need to kill another animal needlessly. And what about these odd story's about predatory animals adopting other animals that would usually be their food source but instead they protect and try to mother them? A lot of this I think has to do with natural instinct coupled with lose of habitat and mans direct impact on the environment.

But again these are just thoughts and opinions. Could our technological advancements and intellectual achievements be thought of as a type evolution? certainly in the sense we are smarter and have easy and convenient lives. But as far as "Biological adaptation", (becoming stronger and more physically resilient) we haven't had the need to evolve. Some people would consider it as de-evolution, to be technologically dependent and less able to survive if that were to be stripped from us.

Again just an opinion.
 
  • #23
gjonesy said:
Basically what I am getting at is if we could turn back the clock say 400 years, where man lived by his knowledge of the land and road beast of burden and our natural predators were still large animals disease and circumstance, and we stayed that way till now, we most likely would have evolved immunity to most common bacterial and viral diseases, there would be far less pollution and the population would be in check. Cancer would probably be the odd occurrence as would most food born and chemically born diseases.

Well, no, we wouldn't have developed an immunity to most diseases nor would cancer be just an odd occurrence (though it would be reduced since the main cause of cancer is old age and people wouldn't be living as long). And I seriously doubt food-borne illnesses would be drastically reduced.

gjonesy said:
I have read some resent studies that people eating whole food diets, natural and organic, with food intake restrictions are far more resilient and healthy then most others.

Then what you've read is probably nonsense. I doubt there has never been any reputable study done that suggests something this broad. Be extremely skeptical of health and food studies, as life is so complicated that it's very difficult to figure out what causes what.

gjonesy said:
If we lived like our ancestors we would only eat what we could gather find fish hunt or kill. Which means we wouldn't be eating very much nor would it contain the chemicals or hormones processed preserved foods do today.

While true, I believe this is the appeal to nature fallacy. And it's exactly that. A fallacy. "Natural" food (or anything else) is not inherently better than other food. In fact it can often be worse, with different bacteria, viruses, and parasites like tapeworms that we rarely have today.

gjonesy said:
But as far as "Biological adaptation", (becoming stronger and more physically resilient) we haven't had the need to evolve. Some people would consider it as de-evolution, to be technologically dependent and less able to survive if that were to be stripped from us.

That's not what biological adaption means. Not all adaptions lead to "stronger and more physically resilient" populations. Evolution by means of natural selection can drive a population to become less physically resilient for a variety of reasons. Also, human beings have had no significant evolutionary changes over the last 10,000 years since agriculture was developed and we began to leave our hunter-gatherer lifestyle. A person born and raised in New York City is genetically nearly identical to someone born and raised in a modern hunter-gatherer society. Our reduced ability to survive in a "natural" environment is purely due to the fact that we don't pass those skills down anymore, not due to anything related to physical changes through evolution.
 
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  • #24
Ygggdrasil said:
Yes, biological evolution is likely not responsible for most cultural and social changes as these occur on too short of a timescale for biological evolution to have an effect.

In this video Richard Dawkins talks about a hypothetical situation and attributes behavior of birds to genetic changes. He goes on to say both fishing and piracy are unstable by themselves and an evolutionarily stable strategy is one when none can do better than the other. Isn't it the same case with humans?
 
  • #25
Drakkith said:
Well, no, we wouldn't have developed an immunity to most diseases nor would cancer be just an odd occurrence (though it would be reduced since the main cause of cancer is old age and people wouldn't be living as long). And I seriously doubt food-borne illnesses would be drastically reduced.

Well maybe i been reading the wrong books and websites, i read a story pubished by the CDC about the 1918 flu pandemic and it stated that many of the victims were young abults and children. The stated reason was the older folks had experienced that type of flu or one very similar to it, and those that had survived although not fully immune had some resistance to that bug. Thats one pubished example. As far as cancer goes...and i have studied that topic before. Ingestion of carcinogenic man made pollution and exposure to some man made material has cause the rise in cases. Again that's documented. I never said there would be no cancer. I just stated it would be an "odd" or less likely occurence.

Now i may be wrong and i will admit that there are arguments against what I am saying...when i say whole foods and organic foods I am not talking about inproper handling contaminated products. Thats dangerous no mater how its grown.
There is a cardiologist i forget his name but he claims that highly processed foods, flour sugars and things of that sort cause systemic inflammation, contributes to heart disease and aids cancer growth.

Now Drakkith i respect you and i follow some of your post, not trying to contradict you cause I am not a doctor. But i have a doctor in my family that believes in a lot of what we are talking about here. Ill admit he's well now SHE'S a bit strange. I am in the process of changing my lifestyle to hopefully live longer and healthier. Hope I am not giving up all this stuff for nothing.
 
  • #26
And please to all, I am not a tree hugger and i am not just parroting rhetoric. I am diabetic and was told point blank by my own physician that a lot of the artificial sweeteners i was consuming were really bad for me. I know there is no genetic differences in a tomato grown in my garden as opposed to those in the supermarket. But mine arent loaded with pesticides. And nothing I've ever hunted and killed for food has ever made me sick. None of the fish I've caught have either. When we are dicussing this topic my understanding and meaning maybe misinterpreted. I like modern convenience as much as anyone else. But these preservatives and additives (artificial coloring and dyes) things that are present in highly processed foods do have an impact on your health and many of them are negative. I'll just leave it at that.

:smile:
 
  • #27
@gjonesy, I'm going to have to ask for references to all that if we want to continue this discussion. And since discussing whether your claims are accurate or not is well off-topic for this thread, you can send me a private message if you'd like to continue.
 
  • #28
I think we need to consider that the original post was about evolution, one of the processes involved in how life changes over time.
Humans have developed an elaborate immune system, largely because our pathogens evolve, they change. We can never consider that our immune system can protect us from all threats, only the ones it recognises and many we will face don't exist yet. I presume the current pandemic should provide evidence enough of that.
I don't know what aspects of cancer you have studied and there are a large number of factors that can effect a persons risk, but it is a complex group of diseases and its true that there are things in our environment that can increase risks, most of these are in fact quite natural and include bacteria, viruses and food products. However cancer results from a number of changes in a cells DNA and the risks of these changes increases with each cell division, as we age these changes accumulate increasing the risk of cancer. So children 0-14 and young people 15-24 each make up less than 1% of the total. Adults aged 25-49 contribute (9%), those aged 50-74 account for (54%) and the over 75 (36%)

The link is to the UK figures but they can be generalised.

https://www.cancerresearchuk.org/health-professional/cancer-statistics/incidence/age#heading-Zero

Information about diet is notoriously unreliable and even when the evidence is reasonable there are always people wanting to distort it in some way. Organic diets are a case in point, the claims are that they provide more healthy vitamins, really the same could be said of any plant based diet, they have lower levels of heavy metals this only reflects the soil they were grown in, and fewer pesticides. This is an interesting one as plants have been engaged in chemical warfare with their predators since they developed, they are much better at it than we are. Its estimated that 99.9% of insecticides we ingest are from the plants we eat and many of the insecticides we use have been developed from plant sources.

https://www.acsh.org/news/2017/06/13/9999-pesticides-we-eat-are-produced-plants-themselves-11415

There is some evidence that our diet can influence the risk of developing certain diseases, though this is frequently overstated but I've yet to see any convincing evidence of a significant effect on overall mortality at the population level.
 
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1. How do human actions contribute to evolution?

Human actions can contribute to evolution in several ways. One important way is through selective pressure. For example, humans have domesticated certain animals and plants, selecting for desired traits and causing those species to evolve. Additionally, human activities such as hunting, pollution, and habitat destruction can directly impact the survival and reproductive success of different species, leading to changes in their genetic makeup over time.

2. Can humans evolve?

Yes, humans can evolve. Evolution is a process that occurs in all living organisms, including humans. While the rate at which humans evolve may be slower compared to other species, our genetic makeup can still change over time in response to environmental pressures and other factors.

3. How does the theory of evolution explain human behavior?

The theory of evolution does not directly explain human behavior. However, it can provide insights into certain behaviors and traits that may have evolved through natural selection. For example, altruistic behaviors, such as helping others, may have evolved because they increase the chances of survival for both individuals and their genetic relatives.

4. Are human actions the only factor in evolution?

No, human actions are not the only factor in evolution. While human activities can have a significant impact on the evolution of certain species, there are also other factors at play such as natural selection, genetic mutations, and environmental changes. These factors all work together to shape the evolution of life on Earth.

5. Can humans control their own evolution?

Humans have the ability to influence their own evolution through selective breeding and genetic engineering. However, it is important to consider the ethical implications of these actions and the potential consequences on future generations. Ultimately, natural selection and other factors will continue to play a significant role in shaping the evolution of humans and other species.

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