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Thread: How can chickens/sheep(no defence mechanism) exist if evolution did happen? Those that survive, survive, and those unfit for survival,dies off.

  1. #1 How can chickens/sheep(no defence mechanism) exist if evolution did happen? Those that survive, survive, and those unfit for survival,dies off. 
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    I read somewhere before, on one of Albert Einstein's comments on the existence of chickens:
    The only reason i can find for why chickens exist is as food for human beings to eat.
    How can chickens exist today if they don't/hardly have any defensive/fleeing mechanism?

    Ducks/penguins are different. They can swim away from land predators/walk away from sea predators.
    Turkey are different too. They vomit semi-digested meat that smells like crap to deter predators.

    The current reason to why they exist is: Humans breed them.
    But what about: Before humans bred them?

    Lets talk about in the wild: Before human's un-wildifying-of-the-earth doings.

    Shouldn't they be extinct? (before humans starting to breed them)


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    Chickens are prolific in reproduction. Sheep are much the same as things like small antelopes, regularly reproduce, often twins.

    So the fact that they may be especially vulnerable to predation, or to eggs being taken by snakes in the case of chickens, doesn't really affect the survival of the species.

    Look at other similar species. Why aren't all the other birds of the South East Asian forests extinct? Plenty of predators there. Why aren't wild breeds of sheep or goats extinct? As far as I know, any extinctions among these breeds has been from habitat loss caused mainly by humans, not from predation.


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    Artificial selection of chickens has made them different from the wild animals they were bred from. Chickens are apparently bred from wild red and gray jungle fowl:

    http://www.telegraph.co.uk/science/s...evolution.html

    By altering DNA, chickens can be grown with alligator like snouts, turning back the clock on evolution:

    Scientists reverse evolution with snouted chicken - Telegraph
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    Chickens are the domesticated subspecies of the Red jungle fowl https://en.wikipedia.org/wiki/Red_Junglefowl (with some possible hybridization with the Grey Jungle fowl https://en.wikipedia.org/wiki/Grey_Junglefowl)

    Both species have coloration that blends with the tropical vegetation of the Southeast Asian wild range, and both are capable of powered flight.

    Given this why would they have been extinct before they were domesticated?

    This same general concept applies to the sheep Ovis aries. The species is domesticated form the wild mouflon native to the Caucasus and the Middle East. It is able to avoid natural predators so why should it be extinct?
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    Quote Originally Posted by ryanawe123 View Post
    How can chickens exist today if they don't/hardly have any defensive/fleeing mechanism?
    I assume you are trying to reconcile some creationist excuses you have heard with evolution. Before you ask such questions maybe you could spend a little time thinking about them and trying to come up with your own ideas.

    One thing that might help you are the following facts:

    1. Creationism is a set of lies and deliberate misunderstandings to support a preconception based on the idiotic idea that you have to take the bible literally (1)

    2. Evolution is a fact: we see it all around us.

    3. The theory(2) of evolution is an attempt to understand and explain how it happens in detail. (3)

    4. There is no contradiction between religion and evolution (4)

    So, when thinking about how chickens survived you need to think about the fact that before domestication they were different in some number of ways and lived in different environments. Clearly they did survive and you might guess that they must have had enough defence mechanisms or sufficiently few predators. Now you are starting to think scientifically. Those are both hypotheses (and you may be able to come up with others). They can be tested: research the known antecedents of domesticated fowl. Look into their environment. And so on. You will end up confirming one or more of your hypotheses and, therefore, evolution.

    Do this a couple of times and you get the official title: Junior Scientist!


    (1) Except when it contradicts itself and then you can come up with all sorts of fanciful interpretations of the words in order to make it consistent.

    (2) Theories, plural, might be more accurate.

    (3) There is an obvious analogy with gravity (a fact) and various theories of gravity (Newtonian, Relativity, MOND, etc) which attempt to explain it.

    (4) Some on the forum will disagree but ... meh. There are religious evolutionary biologists. The Catholic Church accepts evolution. The problem is not religion but some sort of primitive mind-set.
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    Quote Originally Posted by ryanawe123 View Post
    I read somewhere before, on one of Albert Einstein's comments on the existence of chickens:
    The only reason i can find for why chickens exist is as food for human beings to eat.
    How can chickens exist today if they don't/hardly have any defensive/fleeing mechanism?

    Ducks/penguins are different. They can swim away from land predators/walk away from sea predators.
    Turkey are different too. They vomit semi-digested meat that smells like crap to deter predators.

    The current reason to why they exist is: Humans breed them.
    But what about: Before humans bred them?

    Lets talk about in the wild: Before human's un-wildifying-of-the-earth doings.

    Shouldn't they be extinct? (before humans starting to breed them)
    Have you ever tried to catch a chicken that wasn't fenced in? They are not easy to catch, and they have talons and very sharp beaks. And roosters have these huge gouging thorns (spurs) on the back of their legs. They can be vicious. My son used to get stalked by my neighbor's rooster every day. The neighbor let the rooster roam free and my son used to taunt it by making "cockadoodledoo" calls at it. Well silly boy didn't realize that was a claim to territory and he made himself an enemy. every day that rooster would stalk him and attack him at every opportunity. We had a long driveway to the bus and my son had to run like hell to make it to the street in order to get through the area that the rooster considered to be his. My son was too slow a few times and made it in with huge scratches on his arms from the rooster flying up and attacking with talons and spurs.

    Believe me, these birds are not defenseless.
    Neverfly has already demonstrated this with the images he posted.


    You also seem to be operating under the assumption that evolution needs a reason. There is no reason WHY. it just happens. Things exist because they do. There is no need for a purpose except the need you create in your own mind. If there weren't chickens for us to eat, we'd simply eat something else.
    Last edited by seagypsy; April 8th, 2013 at 10:05 AM. Reason: removed redundant images, didn't see NF's post until after posting.
    Speaking badly about people after they are gone and jumping on the bash the band wagon must do very well for a low self-esteem.
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    Also take into account that the current domestic animals may not necessarily be the same in the wild. Look at the pigs you see at farms, the weren't like that when we domesticated them, they were vicious and quite hardy animals. I don't see why a chicken would have any more trouble surviving in the wild than a turkey.
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    wild sheep? do they exist?
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    Quote Originally Posted by ryanawe123 View Post
    wild sheep? do they exist?
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    wild sheep? do they exist?
    Get thee to a search engine. Type in mouflon and image then look at dozens and dozens of pictures of very impressive sheep.
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    Quote Originally Posted by ryanawe123 View Post
    wild sheep? do they exist?
    What planet do you live on?
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    Granted domestic sheep have been evoluntionarily changed by people to maximize their woolliness and minimized their independence but the ancestural wild sheep do exist.
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    Chickens are the dominent terrestrial form of wildlife on many of the Hawaiian islands. They are anything but defenseless.
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    How can chickens exist today if they don't/hardly have any defensive/fleeing mechanism?
    They reproduce at an alarming rate so they are very prolific and keep reproducing more and more of themselves so they can't ever become extinct!
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    Quote Originally Posted by cosmictraveler View Post
    They reproduce at an alarming rate so they are very prolific and keep reproducing more and more of themselves so they can't ever become extinct!
    Although you are joking, that is a strategy used by many species. There are species where nearly all of the offspring will be eaten by predators. Instead of a defence mechanisms, they rely on producing huge numbers of offspring so that even if only 1% survive by chance, it is enough to maintain the population.
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    Quote Originally Posted by Strange View Post
    Although you are joking, that is a strategy used by many species.
    Frogs do that.
    And idiots.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by Strange View Post
    Although you are joking, that is a strategy used by many species.
    Frogs do that.
    That was exactly what I was thinking of as I sit here looking at the masses of frog spawn and some very fat fish in my pond...
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    ryanawe, haven't you ever seen videos of cute newborn sea turtles scurrying from the beach to the sea as predators pick them off one by one? Haven't you ever heard of cockfighting?Edit to add: Where do you think the expression "to ram something" comes from?
    Last edited by Alec Bing; April 10th, 2013 at 04:58 PM.
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    can things evolve in nature by having no defense mechanisms?
    i'm not specifying any individual species in this reply.
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    What are a slugs defenses?
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    Ah but some birds gobble them up. Probably since they are slimy- no need to chew. They just slide right down.
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    Quote Originally Posted by PhDemon View Post
    If they have no predators and/or there are enough of them that some survive to breed despite the fact most get eaten then yes.
    are there examples of animals that do this?
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    Quote Originally Posted by ryanawe123 View Post
    Quote Originally Posted by PhDemon View Post
    If they have no predators and/or there are enough of them that some survive to breed despite the fact most get eaten then yes.
    are there examples of animals that do this?
    SLUGS!
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    You do like slugs, don't you?
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    The thicker slime is a defense mechanism, which makes slugs hard to grip by predators (squirrels, some birds and some beetles eat slugs). The thick slime also tastes very nasty.

    Read more: ICanGarden.com - Gardening Resource Site
    Quote Originally Posted by jocular View Post
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    Quote Originally Posted by ryanawe123 View Post
    You do like slugs, don't you?
    Not for eating. Other than that, they are ok, I guess. Hmmm... have you ever seen a cute slug?
    Although, their little eyestalks are kinda cute... Don't have the urge to nibble on them, though.

    Edit: Damn. Ok well not entirely defenseless... but then, I can't think of anything that is entirely defenseless that is also tasty.
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    Slugs like this?
    ec.gif
    Neverfly likes this.
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    I thought they live on the ground?
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    Back to post #27?
    Quote Originally Posted by jocular View Post
    If thy right nipple offend thee, pluck it off! Goes for the other, too!
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    Quote Originally Posted by PhDemon View Post
    Joke:
    What did the slug say to the snail?
    Big Issue sir?

    [Note for non-UK people the Big Issue is a magazine sold on the streets by homeless people]
    'Til he gets on drugs, and robs a snail...
    Quote Originally Posted by ryanawe123 View Post
    I thought they live on the ground?
    I see them in bushes. Munchin' on leaves and avoiding salt.
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    On the ground?

    I found one of the revolting little sods on the kitchen floor! You may be surprised to learn that I didn't touch it, nor did I squash it. I found something to use to sorta lift it sorta flick it until it went right outside the kitchen door, down the steps and out of sight out of mind. I boiled the kettle and gave the kitchen tool a good bath after that.
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    what about sloths?

    google says its moss growth.. i dont get it.
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    Quote Originally Posted by ryanawe123 View Post
    what about sloths?

    google says its moss growth.. i dont get it.
    That one definitely falls under the 'gross' defense- if you're ever unlucky enough to smell one.

    Moss grows on its fur. It is why the sloth is green in color.
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    google says its moss growth.. i dont get it.
    Sloths live in damp, often dripping, rainforest. They don't move very much, certainly not briskly. So an animal in those conditions has to have a strategy and a biology that promotes its survival. Given their low activity rate, expecting them to shake off the moisture or to groom their coat to remove debris and moulds, mildews or mosses is a bit too much. So their coat acquires moss and that works for them. For all I know it acts as a bit of a raincoat to stop the moisture penetrating to the skin - which would help maintain an even body temperature.

    Just as we have kilos of bacteria within our gut to help with our digestion and lots of little critters in our eyelashes and other places that all help to keep the organism functioning well.

    This is interesting, but does nothing for my raincoat hypothesis. Sloth fur has symbiotic relationship with green algae - BioMed Central blog
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    Quote Originally Posted by adelady View Post
    google says its moss growth.. i dont get it.
    Sloths live in damp, often dripping, rainforest. They don't move very much, certainly not briskly. So an animal in those conditions has to have a strategy and a biology that promotes its survival. Given their low activity rate, expecting them to shake off the moisture or to groom their coat to remove debris and moulds, mildews or mosses is a bit too much. So their coat acquires moss and that works for them. For all I know it acts as a bit of a raincoat to stop the moisture penetrating to the skin - which would help maintain an even body temperature.Just as we have kilos of bacteria within our gut to help with our digestion and lots of little critters in our eyelashes and other places that all help to keep the organism functioning well. This is interesting, but does nothing for my raincoat hypothesis. Sloth fur has symbiotic relationship with green algae - BioMed Central blog
    The moss coat is probably very good camouflage. There's your defense mechanism.
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    Quote Originally Posted by ryanawe123 View Post
    can things evolve in nature by having no defense mechanisms?
    i'm not specifying any individual species in this reply.
    Errmmm...

    Quote Originally Posted by Strange View Post
    Quote Originally Posted by cosmictraveler View Post
    They reproduce at an alarming rate so they are very prolific and keep reproducing more and more of themselves so they can't ever become extinct!
    Although you are joking, that is a strategy used by many species. There are species where nearly all of the offspring will be eaten by predators. Instead of a defence mechanisms, they rely on producing huge numbers of offspring so that even if only 1% survive by chance, it is enough to maintain the population.
    Frogs, turtles, flies, some fish, many plants, etc.

    In fact, I wouldn't be surprised if this was the main survival strategy. It seems to be relatively few species that can afford the luxury of having a small number of offspring.

    The other thing that animals can do is hide. Maybe they only come out at night when predators are asleep (or vice versa), or they stay underground or in deep water, etc.
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    The ability to raise a small number of offspring to adulthood would probably require some type of social organisation, so that adults can work together to protect the young. The ability to form social relationships requires a certain level of intelligence.
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    Quote Originally Posted by Alec Bing View Post
    The ability to raise a small number of offspring to adulthood would probably require some type of social organisation, so that adults can work together to protect the young. The ability to form social relationships requires a certain level of intelligence.
    Wolves.
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    Quote Originally Posted by Alec Bing View Post
    The ability to raise a small number of offspring to adulthood would probably require some type of social organisation, so that adults can work together to protect the young. The ability to form social relationships requires a certain level of intelligence.
    Good point.

    Or very effective defence/camouflage/protection so that the one or two offspring have a high chance of survival. Struggling to think of a good example though ...
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    Quote Originally Posted by Strange View Post
    Frogs, turtles, flies, some fish, many plants, etc.
    talking about animals(not plants[in this reply])
    frog,. they can jump away to escape
    flies, they can fly away to escape
    fish, they can swim away/disguise to escape (what specific fishes are you talking about?)

    aren't there any creatures that only use
    Quote Originally Posted by cosmictraveler View Post
    reproduce at an alarming rate, keep reproducing more and more of themselves so they can't ever become extinct!
    this to survive? and does not have any defense mechanism?
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    Quote Originally Posted by ryanawe123 View Post
    fish, they can swim away/disguise to escape (what specific fishes are you talking about?)
    As far as I know all, or nearly all, oviparous fish produce thousands of eggs (this may also be a result of the way they are fertilised).

    aren't there any creatures that only use
    Quote Originally Posted by cosmictraveler View Post
    reproduce at an alarming rate, keep reproducing more and more of themselves so they can't ever become extinct!
    this to survive? and does not have any defense mechanism?
    What a bizarre question. So only animals that cannot move at all? I doubt it. But no organism depends on a single defence mechanism.

    There are various sessile animals, mainly marine, that attach themselves to a rock and are unable to move. But they will use a variety of defence mechanisms which may include large numbers of offspring, a shell, etc.
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    Looking at mammals and defence or camouflage.

    One defence is safety in numbers. Wildebeest and zebra usually only produce one infant at a time. Their main "defence" is to stay with the herd. It's the injured, the weaklings and the stragglers who get picked off by predators or die of thirst or starvation if they don't keep up.

    For others, it's a mother clued up enough to keep the young ones safe or to fight viciously to protect them - polar bears? Though we usually see avoiding the adult males as the prime strategy.

    Camouflage? The cubs of the solitary big cats have markings suitable for them to be more or less hidden in plain sight. One thing I've never learned is how the mothers make the little ones stay where she puts them when she goes off hunting. Scent markings perhaps, or something else?
    The young of deer and antelopes are often differently marked in a way that makes them a bit harder to see among foliage. Same thing for lots of ground nesting birds.
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    Quote Originally Posted by adelady View Post
    One defence is safety in numbers.
    Speaking of which, we are due for a hatch of 17 year locusts (cicadas) on the east coast this year. These critters hatch in huge numbers, which cannot possibly be consumed all at once. The 17 year cycle makes it difficult for any predators to rely on this source of food. Some think it's significant that 17 is a prime number. There are also 13 year locusts, also a prime number.
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    Quote Originally Posted by Strange View Post
    What a bizarre question. So only animals that cannot move at all? I doubt it. But no organism depends on a single defence mechanism.
    no. not: do not move at all.
    it could also mean that they move slowly, or cant sprint at high speeds.
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    In the ocean at least the immovable (or, near as dammit is to swearing, immovable) generally have defences like poison or the capacity to shrink or fold back into a much less accessible form.
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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    Plants have thorns, toxins, etc. Another technique is to mimic an organism that is dangerous when you are not.
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    Quote Originally Posted by Alec Bing View Post
    Plants have thorns, toxins, etc. Another technique is to mimic an organism that is dangerous when you are not.
    And the same general set of techniques are used by sessile or slow moving animals. Not surprisingly, as they work.
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    Quote Originally Posted by ryanawe123 View Post
    it could also mean that they move slowly, or cant sprint at high speeds.
    Flies, for example, can move at high speeds but are eaten in vast numbers by fast moving predators. They also have a slow moving larval stage. So they use large numbers of offspring as one of their survival mechanisms.
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    How can chickens exist today if they don't/hardly have any defensive/fleeing mechanism?
    Are you serious ? Obviously you have never faced an angry chicken. They are vicious beasts !
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    I got attacked by a rabbit once. It drew blood.
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    this thread is a real hoot

    and a really fun break from doing my taxes
    thanx to all
    ...............
    and a whole new meaning to "slug fest"
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    Quote Originally Posted by Markus Hanke View Post
    How can chickens exist today if they don't/hardly have any defensive/fleeing mechanism?
    They do!
    But it's hidden in secret silos until deployed.
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    Quote Originally Posted by sculptor View Post


    this thread is a real hoot

    and a really fun break from doing my taxes
    thanx to all
    ...............
    and a whole new meaning to "slug fest"
    That final comment is so awful I can't decide if it's so bad it deserves a "like" or it's so bad YOU deserve a ban!
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    do domesticated sheep/pigs have defence mechanisms?
    Quote Originally Posted by jocular View Post
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    Quote Originally Posted by ryanawe123 View Post
    do domesticated sheep/pigs have defence mechanisms?
    They have some of the same defense mechanisms as their non domesticated versions.

    Pigs wild or domestic have sharp hooves as well as sharp teeth. I am referring to the upper and lower canine teeth (thats the fangy ones) they just don't grow into tusks in the domestic breed.

    And domestic sheep still grow horns and have very thick skulls. And being headbutted by one is pretty damned painful if they are actually mad at you when they do it. I have only been headbutted by young sheep when they were playing and that hurt bad enough. And their hooves are also quite sharp.
    Speaking badly about people after they are gone and jumping on the bash the band wagon must do very well for a low self-esteem.
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    Quote Originally Posted by ryanawe123 View Post
    do domesticated sheep/pigs have defence mechanisms?
    yes can you guess what they are based of the information we have already provided you?
    If more of us valued food and cheer and song above hoarded gold, it would be a merrier world. -Thorin Oakenshield

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    Do physical adaptations(in an individual creature's lifetime) alter the genes?
    sorry if my biology is weak.
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    Quote Originally Posted by ryanawe123 View Post
    Do physical adaptations(in an individual creature's lifetime) alter the genes?
    sorry if my biology is weak.
    No, it is the other way around. Genes alter the physical adaptations.
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    So, genes do change in an individual creature's lifetime?
    Quote Originally Posted by jocular View Post
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    Quote Originally Posted by ryanawe123 View Post
    So, genes do change in an individual creature's lifetime?
    They can do (e.g. if they are exposed to radiation, for example). But I'm not sure why you are asking. It suggests you misunderstood the previous point in some way. So let's step back a bit.

    You asked:
    Do physical adaptations(in an individual creature's lifetime) alter the genes?
    By this, are you thinking that if someone does a lot of exercise and gets stronger, for example, or eats too much and gets fat, will this alter their genes and be passed on to their offspring?

    If so, the answer is, no (*).

    This was the basis of an alternative theory of evolution (see, it wasn't just Darwin) from a scientist called Lamarck. This was proved to be incorrect by experiment and observation (unlike Darwin's theory).
    Lamarckism - Wikipedia, the free encyclopedia

    (*) With the caveat that there are "epigenetic" effects which can be influenced by an organism's environment, health, etc which can have an effect on the next generation (or, more controversially, next two generations). But this alters the way genes are "packaged" and expressed rather than changing the genes themselves.

    Hope that helps...
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    Thanks strange,

    but when you say
    Quote Originally Posted by Strange View Post
    They can do (e.g. if they are exposed to radiation, for example).
    Im confused. Generally, do all cells in the human body share the same genetic code in the nucleus?
    Quote Originally Posted by jocular View Post
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    Quote Originally Posted by ryanawe123 View Post
    Thanks strange,

    but when you say
    Quote Originally Posted by Strange View Post
    They can do (e.g. if they are exposed to radiation, for example).
    Im confused. Generally, do all cells in the human body share the same genetic code in the nucleus?
    Yes, they do. In general.

    But a single cell can mutate, for example. It may then die or be killed off by the immune system. Or it may grow and turn cancerous.

    And there are exceptions. At one extreme, we have cells that contain no genes (e.g. red blood cells). Then there are cells that contain only half the genes (sperm and eggs). And there is recent research that suggests that neurons in the brain "shuffle" some of their genetic material during development. This may be part of the reason we are all so different as people.
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    Just a note, a red blood "cell" is not a cell, but rather a complex enzyme.
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    But they do have lipid cell walls and cytoplasm. (Don't they?) So perhaps it depends how far you want to stretch the definition of "cell". Do they contain any organelles? Or just cytoplasm and haemoglobin?
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by ryanawe123 View Post
    Thanks strange,

    but when you say
    Quote Originally Posted by Strange View Post
    They can do (e.g. if they are exposed to radiation, for example).
    Im confused. Generally, do all cells in the human body share the same genetic code in the nucleus?
    Yes, they do.
    so all the genes that father can possibly transfer to son, can only be the genes that the father has when father was an embryo?
    Quote Originally Posted by jocular View Post
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    Yes.
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    black-sheep(1).jpg Actually, in New Zealand, sheep are the dominant predators. They've been known to wipe out entire villages of human beings in only a few hours. Don't be fooled my friend, the sheep WANT you to think they're defenseless, right before they rip your legs off.
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    RBC's are cells. They are anucleate cells, losing their nucleus during maturation.
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    Quote Originally Posted by Strange View Post
    But they do have lipid cell walls and cytoplasm. (Don't they?) So perhaps it depends how far you want to stretch the definition of "cell". Do they contain any organelles? Or just cytoplasm and haemoglobin?
    Looked a little more and yes they do have a lipid membrane and cytoplasm, but no nucleus, which is almost unique for vertebrate species
    If more of us valued food and cheer and song above hoarded gold, it would be a merrier world. -Thorin Oakenshield

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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by ryanawe123 View Post
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by ryanawe123 View Post
    Thanks strange,

    but when you say
    Quote Originally Posted by Strange View Post
    They can do (e.g. if they are exposed to radiation, for example).
    Im confused. Generally, do all cells in the human body share the same genetic code in the nucleus?
    Yes, they do.
    so all the genes that father can possibly transfer to son, can only be the genes that the father has when father was an embryo?
    Yes.
    so genetic coding of all cells in the body cannot be altered by changing environments? (e.g. ice age coming, growing fur)
    Quote Originally Posted by jocular View Post
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    so genetic coding of all cells in the body cannot be altered by changing environments? (e.g. ice age coming, growing fur)
    It's the other way around ..... sort of.

    We've discussed this elsewhere. Organisms have all sorts of genetic material that allows variations - eye colour and height would be the classic examples for humans.

    When the environment changes, some of those variations - which might not even be visible, like say, an ability to extract certain vitamins or minerals from unpromising foods - might become more important to survival. If that environmental change persists, then the members of the species that possess a variation which gives them a better chance of survival than those which don't will, sooner or later, become a larger portion.

    Or they could be like the great pandas. They've evolved through time to occupy a particular ecological niche, entirely dependent on a single food source. Obviously it was advantageous at some point, but they're now stuck on a red queen's racetrack (running like hell to stay in the same place). Their environment has changed very quickly because of human destruction of the ecology they're part of. That change is much, much too fast for any gradual change to help them. It's entirely possible that some pandas have, or had, some capacity to benefit from eating something other than bamboo, maybe some of the insects that inhabit the bamboo could be ingested and would be an obvious opportunity to develop a slightly modified digestive /metabolic system. For such a change in the biology to become both beneficial and widespread would take unknown numbers of generations - remember these are very, very slow reproducers.

    It's pretty obvious that they will become extinct in the wild in a century or so unless something truly remarkable happens to reinstate and expand their preferred, well it's actually essential, environment.
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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    No.
    Alterations in the genetic code result in animals that have diversity.

    Environment has a direct effect on populations. Diversity can lead to some animals having advantages others withing a population lack. These advantages can help the animal breed more often or survive to live to breeding age with better success.

    In spite of the claims of some, there is no evidence that environmental pressures stimulate specific genetic change.
    Those that believe it does are ignoring an overwhelmingly diverse fossil record and massive time scales involved.
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    Quote Originally Posted by ryanawe123 View Post
    so genetic coding of all cells in the body cannot be altered by changing environments? (e.g. ice age coming, growing fur)
    A change in the environment would not change the genes in your cells.

    Growing fur would be caused by the genes, not the other way round.

    Now, consider that you have a population of people/animals. Some are quite furry and some are less furry (the usual variation within a population). Then, an ice age comes, those less furry ones are less likely to survive. The furrier ones are more likely to survive. The offspring of two furrier parents may be even ore furry (and even more likely to survive). Eventually, maybe a few offspring are born with a modified gene that makes them even furrier. They are even more likely to survive. And so on.
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    1)
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by ryanawe123 View Post
    Do things that a creature chooses (meat) in its lifetime alter its genetic code?
    No.
    2)
    Quote Originally Posted by Strange View Post
    Do physical adaptations(in an individual creature's lifetime) alter the genes?
    By this, are you thinking that if someone does a lot of exercise and gets stronger, for example, or eats too much and gets fat, will this alter their genes and be passed on to their offspring?

    If so, the answer is, no (*).
    3)
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by ryanawe123 View Post

    so all the genes that father can possibly transfer to son, can only be the genes that the father has when father was an embryo?
    Yes.
    So asexual animals's offspring's genetic code are the same as its greatgreatgreatgreatgrandparents?
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    So asexual animals's offspring are exactly same as its parent's?
    Yup. That's why sexual reproduction is so successful. Non-sexual reproduction means that the species in question is basically hostage to whatever its original genetic structure was. So if a disease affects one, it affects all. If a change in circumstances is deadly to any one of the individuals, it's deadly to all.

    Sexual reproduction is like having money in the species bank. You're much more likely to have some individuals who are more resistant to a disease, or more capable of adapting their diet in a particular way, or more able to adapt lifestyle in certain ways. If you do have some such individuals when circumstances change in a certain direction, the species may have a better chance of avoiding extinction if enough individuals have enough time for that genetic advantage to dominate and to ensure survival.

    Our species managed to get through a bottleneck where our numbers were severely reduced a long time ago. Look at us now!
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    Quote Originally Posted by ryanawe123 View Post
    So asexual animals's offspring's genetic code are the same as its greatgreatgreatgreatgrandparents?
    Not necessarily, because change can occur during the copying (transcription) of the genes.

    So ...

    Quote Originally Posted by ryanawe123 View Post
    so all the genes that father can possibly transfer to son, can only be the genes that the father has when father was an embryo?
    Those genes may be modified during reproduction. (They may be changed during the father's lifetime, e.g. by radiation, but that is a lot more unlikely.)
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    Okaay. I simplified a bit.

    Take mine and add Strange's and you get the idea.

    Basically the survival of a species that uses asexual reproduction relies much more on repeated pure luck than a sexually reproducing species does. The genetic money in the bank idea still works.
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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    Is the only way to domesticate an animal by using selected breeding?
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    Quote Originally Posted by ryanawe123 View Post
    Is the only way to domesticate an animal by using selected breeding?
    Yep. That is the definition of domestication.
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by ryanawe123 View Post
    Is the only way to domesticate an animal by using selected breeding?
    Yep. That is the definition of domestication.
    Does that apply to domesticated horses as well? I have read plenty of stories of wild horses being captured and broken and made into pets as well as domestic horses getting lost only to be found as part of a wild herd later. And that there really isn't any physical difference in the two.
    Speaking badly about people after they are gone and jumping on the bash the band wagon must do very well for a low self-esteem.
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    Quote Originally Posted by seagypsy View Post
    Does that apply to domesticated horses as well? I have read plenty of stories of wild horses being captured and broken and made into pets as well as domestic horses getting lost only to be found as part of a wild herd later. And that there really isn't any physical difference in the two.
    Interesting question. The wikipedia article on domestication draws a distinction with taming ("the process by which animals become accustomed to human presence").

    I don't know much about horses, but are "wild" horses actually a domesticated animals that have gone wild?
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by seagypsy View Post
    Does that apply to domesticated horses as well? I have read plenty of stories of wild horses being captured and broken and made into pets as well as domestic horses getting lost only to be found as part of a wild herd later. And that there really isn't any physical difference in the two.
    Interesting question. The wikipedia article on domestication draws a distinction with taming ("the process by which animals become accustomed to human presence").

    I don't know much about horses, but are "wild" horses actually a domesticated animals that have gone wild?
    That may be the case. I think horses only arrived in North America when the Spaniards brought them over. Some must have escaped to form wild herds. So that leaves the question; What was the original non-domesticated horse and has it gone extinct?
    Speaking badly about people after they are gone and jumping on the bash the band wagon must do very well for a low self-esteem.
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    Aha!
    A truly wild horse is a species or subspecies with no ancestors that were ever domesticated. Therefore, most "wild" horses today are actually feral horses, animals that escaped or were turned loose from domestic herds and the descendants of those animals
    Horse - Wikipedia, the free encyclopedia
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    Quote Originally Posted by Strange View Post
    Aha!
    A truly wild horse is a species or subspecies with no ancestors that were ever domesticated. Therefore, most "wild" horses today are actually feral horses, animals that escaped or were turned loose from domestic herds and the descendants of those animals
    Horse - Wikipedia, the free encyclopedia
    And from that, this is the only never-domesticated horse still in existence.Przewalski's horse - Wikipedia, the free encyclopedia


    Looks a lot like the domesticated horse of today. And it was native to Mongolia, which means they could have come over by the land bridge between china and alaska. But they died out in north america. And did not make a come back until spaniards brought over the domesticated version and some got loose.
    Speaking badly about people after they are gone and jumping on the bash the band wagon must do very well for a low self-esteem.
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    Quote Originally Posted by seagypsy View Post
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by seagypsy View Post
    Does that apply to domesticated horses as well? I have read plenty of stories of wild horses being captured and broken and made into pets as well as domestic horses getting lost only to be found as part of a wild herd later. And that there really isn't any physical difference in the two.
    Interesting question. The wikipedia article on domestication draws a distinction with taming ("the process by which animals become accustomed to human presence").

    I don't know much about horses, but are "wild" horses actually a domesticated animals that have gone wild?
    That may be the case. I think horses only arrived in North America when the Spaniards brought them over. Some must have escaped to form wild herds. So that leaves the question; What was the original non-domesticated horse and has it gone extinct?
    Thats an easy one, the species and genera of horses that were native to North America which traveled west across the bearing land bridge during the Pleistocene survived, while the species that stayed in North America were not able to adapt to the floral changes of the ice age and went extinct. All non-domestic horses loose in North America now are feral, rather then wild.
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    Quote Originally Posted by Paleoichneum View Post
    Quote Originally Posted by seagypsy View Post
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by seagypsy View Post
    Does that apply to domesticated horses as well? I have read plenty of stories of wild horses being captured and broken and made into pets as well as domestic horses getting lost only to be found as part of a wild herd later. And that there really isn't any physical difference in the two.
    Interesting question. The wikipedia article on domestication draws a distinction with taming ("the process by which animals become accustomed to human presence").

    I don't know much about horses, but are "wild" horses actually a domesticated animals that have gone wild?
    That may be the case. I think horses only arrived in North America when the Spaniards brought them over. Some must have escaped to form wild herds. So that leaves the question; What was the original non-domesticated horse and has it gone extinct?
    Thats an easy one, the species and genera of horses that were native to North America which traveled west across the bearing land bridge during the Pleistocene survived, while the species that stayed in North America were not able to adapt to the floral changes of the ice age and went extinct. All non-domestic horses loose in North America now are feral, rather then wild.
    Thanks for the clarification. I always think of things coming from Asia to North America via the land bridge, I don't know why I never consider that something may start in NA and migrate to Asia. I guess I just get accustomed to everyone wanting to be American for some silly reason lol..
    Speaking badly about people after they are gone and jumping on the bash the band wagon must do very well for a low self-esteem.
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    Camels and Rhinos did the North America to Asia migration too.
    If more of us valued food and cheer and song above hoarded gold, it would be a merrier world. -Thorin Oakenshield

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    Quote Originally Posted by ryanawe123 View Post
    Is the only way to domesticate an animal by using selected breeding?
    The first domesticated animals had to have been wild, but all domesticated animals now are selected by breeding. That is the way to make them more suitable for the purpose.
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    Since starfish are asexual, why are there so many different kinds of starfish?
    Are they considered the same species?
    If yes, how can they be considered the same species if they dont interbreed?
    if no, why not consider them the same species?
    What do we look for to consider two individuals to be: the same species?
    Can they interbreed?



    haha the last question is a trick question.
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    Quote Originally Posted by Wikipedia:Starfish
    Starfish or sea stars are echinoderms belonging to the class Asteroidea ... About 1,800 living species of starfish occur in all the world's oceans. ... Most species of starfish are dioecious, there being separate male and female individuals.
    Starfish - Wikipedia, the free encyclopedia

    Note that the ability to interbreed is not the only way of defining a species. It is a rather woolly concept and there are several definitions which might be used in different contexts. In the end it is just a matter of convention. (That is part of the problem with creationists objection to the creation of "new species"; we invented the division so why should nature care.)

    This page has a good summary of the problems of defining what species means and explains some of the main definitions used: Observed Instances of Speciation
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    Quote Originally Posted by ryanawe123 View Post
    Since starfish are asexual, why are there so many different kinds of starfish?
    Are they considered the same species?
    If yes, how can they be considered the same species if they dont interbreed?
    if no, why not consider them the same species?
    What do we look for to consider two individuals to be: the same species?
    Can they interbreed?



    haha the last question is a trick question.
    Who said they are asexual? most species have both males and females, some have to ability to be hermaphroditic and some are completely hermaphroditic.
    If more of us valued food and cheer and song above hoarded gold, it would be a merrier world. -Thorin Oakenshield

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    Thanks for that Paleoichneum.

    I was a bit perplexed by that asexual remark but I didn't follow it up for some reason (perhaps no reason, I forget).
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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    A very interesting thread, and I find the Horse Scenario rather fascinating. I will definitely read more into it. I was always under the impression, as I assume most are, that the horse populations of the Americas were a direct cause of the Spanish Colonization. I never really thought about the Asia-America migration could have, and really should have, happened both ways.

    Also, I would like to raise a question on a similar issue as the great panda. Us humans. Our digestive tract is not designed to handle red meat; just as we are, for the most part, lactose-intolerant. Given enough time, this should change, no? Our genes, being exposed to red meat for centuries upon centuries (arguing that beef will be a part of our diet for centuries to come) will become more apt to accepting red meat.
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    Our digestive tract is not designed to handle red meat
    Citation needed.
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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    OP, you're vastly underestimating sheep. Wild sheep (mouflon) are smart and they are more than capable of taking care of themselves.
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    Quote Originally Posted by adelady View Post
    Our digestive tract is not designed to handle red meat
    Citation needed.
    Mine does a pretty good job with it given I shovel more into there than Elvis.
    "Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us." -Calvin
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    Quote Originally Posted by Flick Montana View Post
    Quote Originally Posted by adelady View Post
    Our digestive tract is not designed to handle red meat
    Citation needed.
    Mine does a pretty good job with it given I shovel more into there than Elvis.
    I have never heard of anyone from becoming ill after eating red meat unless the meat was contaminated. Tired and bloated if they ate too much, but not ill. On the other hand, I, myself, am lactose intolerant. It is not pretty. If you eat something that your digestive tract is not designed for, it can be very obvious.
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    Quote Originally Posted by ryanawe123 View Post
    I read somewhere before, on one of Albert Einstein's comments on the existence of chickens:
    The only reason i can find for why chickens exist is as food for human beings to eat.
    Shouldn't they be extinct? (before humans starting to breed them)
    The predecessor of the chicken would have been adapted to its environment, and had suitable "defences".
    Domestics animals' "defences" are "humans".


    Quote Originally Posted by Neverfly View Post
    No.
    Alterations in the genetic code result in animals that have diversity.

    Environment has a direct effect on populations. Diversity can lead to some animals having advantages others withing a population lack. These advantages can help the animal breed more often or survive to live to breeding age with better success.

    In spite of the claims of some, there is no evidence that environmental pressures stimulate specific genetic change.
    Those that believe it does are ignoring an overwhelmingly diverse fossil record and massive time scales involved.
    Quote Originally Posted by adelady View Post
    so genetic coding of all cells in the body cannot be altered by changing environments? (e.g. ice age coming, growing fur)
    It's the other way around ..... sort of.

    We've discussed this elsewhere. Organisms have all sorts of genetic material that allows variations - eye colour and height would be the classic examples for humans.

    When the environment changes, some of those variations - which might not even be visible, like say, an ability to extract certain vitamins or minerals from unpromising foods - might become more important to survival. If that environmental change persists, then the members of the species that possess a variation which gives them a better chance of survival than those which don't will, sooner or later, become a larger portion.
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by ryanawe123 View Post
    so genetic coding of all cells in the body cannot be altered by changing environments? (e.g. ice age coming, growing fur)
    A change in the environment would not change the genes in your cells.

    Growing fur would be caused by the genes, not the other way round.

    Strictly speaking, the genetic code is not changed, except though radiation etc, however, sections of the code can be activated and deactivated, and this can be caused by environmental factors. The environment thus has an effect on gene expression and appears to affect the characteristics of an organism. This effect can also be inherited. For a simple example, the children of men who lived through times of starvation have longer life expectancies than those born to men who lived through times of glut.

    Effects, such as predisposition to obesity, are also observed, even in the grandchildren, when the father is a smoker in his 20's, quits, and has kids in his 30's



    Quote Originally Posted by Beyondthought View Post
    Our digestive tract is not designed to handle red meat; just as we are, for the most part, lactose-intolerant. Given enough time, this should change, no? Our genes, being exposed to red meat for centuries upon centuries (arguing that beef will be a part of our diet for centuries to come) will become more apt to accepting red meat.
    Vegetarians

    Organisms are not designed. Humans have consumed meat for millions of years. There is little difference between white and red meat in terms of digestion, at least once it is cooked. Most European adults are well adapted to consuming cow milk, lactose intolerance is a minority condition.

    Genes are not exposed to conditions. The organism is exposed to conditions, those with the better adapted characteristics pass on their genes more effectively, and they become more prolific in the population. On the flip side, although a characteristic may be beneficial for a particular function (e.g digesting meat) it may have negative effects (e.g less efficient at digesting plant matter) which means that it does not become entirely dominant, and you see results like "humans are not as good as digesting animal products as cats"
    adelady and Neverfly like this.
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