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Which road is the chicken crossing?

  1. Sep 23, 2010 #1
    This is not a homework question, not a theory, not a debate about evolution v creation, don't turn into such, please.
    I'm just curious; is the chicken an animal that is evolving into a flighted bird, or a flighted bird that is evolving into a quad? OR are there some species of chickens going one way and others the other way? What will those wings be used for in the future?
    I'm not a biologist, so I am hoping there will be scholarly information.
    Mods, if Posters say things like 'twaddle' and 'chicken wings with beer could you just remove those Replies, instead of closing the Thread!?
    If the chickens were flighted birds, and that is only one possibility, as they could be evolving towards flighted animals, did they just get conditioned by apes who could keep them in toasty barns?
    Is this simple 'biology' that the great biologists and evolutionists have already explained?
    [Really - scientific and scholarly Replies or not at all - we shall see]
    It's either A. a completely analyzed and documented question or B. an interesting scientific curiosity.
     
  2. jcsd
  3. Sep 23, 2010 #2

    lisab

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    It's my understanding that birds who find themselves in environments where there is little advantage to flight, lose that capability. Think dodos and emus. Flying is expensive, biologically speaking.

    From the wiki on the Red Junglefowl (the ancestor of today's domestic chicken):

    http://en.wikipedia.org/wiki/Red_Junglefowl

    I used to raise hens, and that's about how much they could fly, too. But I doubt very much that the birds you find in factory chicken farms could fly anything close to that much. In fact I'd be surprised if they could lift their weight off the ground even for a second.

    So I'd suggest that the domestic chicken's flying ability is decreasing, given these facts:
    • its ancestor wasn't a great flier to begin with, and
    • modern farming methods are reducing the need for flight the flight.

    And I didn't even mention beer :wink:.
     
  4. Sep 23, 2010 #3

    ok, so to answer question 1, I would say neither. The chicken is a perfectly evolved animal for its environment as it is - unless its environment changes (e.g. chickens find themselves in the wild, or some intraspecies or interspecies competition puts pressure on chickens to change in some way to enable them to survive better, these are just examples of environmental change) then there is no need for the chicken to change in any way.

    question 2, like Lisa said, they lost the ability to fly because of human artificial selection over centuries. Humans selected for offspring of the red jungle fowl for ones that didnt fly (I'm guessing here cos I'm no chicken expert, but it makes sense: less flying = more energy for growth) so the chickens we see today dont really fly. So yes, humans made the chickens the way they are by artificial selection.

    um, I know that we belong to the apes, but because 'apes' also has a derogatory meaning, you are putting your intentions at risk of misunderstanding by others by calling people 'apes'.
     
    Last edited: Sep 23, 2010
  5. Sep 23, 2010 #4
    yeah, evolution is actually a simple process, thats why it is so amazing, and why Darwin is brilliant to have discovered it - its often easy to complicate things, and under the obligatorily religious times he lived in, I think it would have taken a lot of brains and guts to think of evolution and then stand by it like he did.
     
  6. Sep 23, 2010 #5
    I mean that the process itself (as I understood it) is simple, but the implications of evolution are ginormous! Its pretty much everything we see around us!

    so, I would recommend (again) that you read about evolution. if Darwin's book is too hardcore, try Richard Dawkins, basically, the more you read about it, the more it makes sense.

    try this: http://www.newscientist.com/article/dn9953-instant-expert-evolution.html
     
  7. Sep 23, 2010 #6
    Lisab; Dodos and Emus, Egads I wasn't even thinking of penguins, ostriches, kiwis. duh me
    I'm trying to get my mind around the evolution thing. When you say ancestors of chickens, I'm thinking ancestors of ancestors of ancestors.
    All of the modern thinking has the flightless birds losing the ability. Now, think about this, all of the very first birds had to, logically, be flightless animals who evolved into flighted ones.
    We, apes and all, came from the primordial muds, not the primordial clouds, unless there was some kind prevailing wind that kept simple creatures airborne for millions of years, developing that way.
    Given, the hypothesis, birds evolved from flightless creatures, likelihood is 99.9999%; then A. I would like to see the family tree. I have observed great scientists, like Dawkins don't hang out here but I am hoping someone has contact with a bright professor, or two, or links where this question has been dealt with.
    B. Why is it 100% of the flightless birds evolved from flighted, when the other million bird species went the other way? Maybe, just maybe, some of the, present day, flightless birds are just late bloomers and are, also, evolving towards flight. Maybe some used to fly but maybe some will fly anon, like the rest learned, or evolved, to do.
    [NG, I'm not calling anybody an ape, on the street; in this Forum I'm just trying to use the correct terminology. Krauss and Dawkins calls us apes.]
    But let's stick to this topic of bird flight, please.
    Have evolutionists, based on the hypothesis all flightless birds used to fly, categorised any others who are on their way to flightless? Seems odd if a couple of dozen out of millions 'evolved' this way, there should be at least 1000 others following the process, eh?
     
  8. Sep 23, 2010 #7
    Partly this is a question of classification, a flightless animal that is now flightless, never having evolved into a bird is called a lizard - you could argue that some species of flying lizards are on their way to evolving into 'birds'. But being able to fly or not isn't a characteristic of a bird.

    The same thing happens with sea mammals, whales, dolphins, seals, manatees etc evolved from land mammals that evolved from reptiles, that had evolved from fish - that of course lived in the sea.
    That cetaceans and pinnipeds make a good living splashing around in the water today doesn't have a lot to do with them having evolved from fish 250million years ago. The sea just has a lot of advantages as a place to live.
     
  9. Sep 23, 2010 #8
    Well heres a well refrenced site with lots of interesting pictures and videos: http://people.eku.edu/ritchisong/554notes1.html

    All birds share the raptor base model with some modifications.

    Feathers are truely ancient as they exsist in the reptile line in alligators, whtich predate the dinosaurs: http://www.ncbi.nlm.nih.gov/pubmed/17784647

    And birds start growing teeth until their genes shut them off whitch draws another line back to their raptor lineage: http://www.timesonline.co.uk/tol/news/world/article1138908.ece

    Chickens are animals that are responding to the selective pressures we have initiated through domistication. Unluckly for them in a few thousand more years that will probably lead them to a dead end. They have no natural place in nature anymore and probably wont make it a few generations after we stop supporting them.
     
    Last edited: Sep 23, 2010
  10. Sep 23, 2010 #9

    DaveC426913

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    Yes. Read up on Archaeopteryx. It is a precursor to flighted birds.

    In a nutshell, the prevailing theory is that lizard-like creatures evolved featherlike extensions on their limbs.

    When escaping from predators, these featherlike extensions allowed them to glide slightly father than their featherless siblings. Fast forward 10 million years and you have an ecology where feathered lizards have persevered where featherless ones have been eaten.

    Here is the critical thing to understand:
    These featherlike extensions did not initally evolve as gliding surfaces; they evolved for some utterly unrelated reason - perhaps as a mating display, or a downy coat for winters. It is only a side-effect that they ended up serving the bird in a totally different way when its environment changed.
    This is key to understanding evolution.

    Because evolution is directionless. It is often driven by environmental and geographic differences. Percurors to penguins were able to fill a niche in the antarctic. The niche is fish. Flight is useless to a creature that swims to survive.

    No. Evolution is not "headed" anywhere; it has no program.

    Current flightless birds will re-evolve flight if and only if it gives them an advantage (often when their environment changtes, or a niche is left open).

    It's about environment and geography.

    Note that it works the other way too. Lizards are not the onlyt creature to have discovered the untapped niche that is the shy.

    Tiny mammals have managed to do so as well. Bats. Completely different creature, put in the same environment, finds the same solution. All those mosquitos, just waiting around for some little mammal that can drop out of a tree and glide long enough to snatch them up.
     
    Last edited: Sep 23, 2010
  11. Sep 23, 2010 #10

    Evo

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    Twice now I've seen you refer to apes and evolution. You are aware that we are not descended from apes?

    As lisab pointed out, chickens have been bred for specific qualities, and flight is not one of those qualities.

    There is no reason to believe that the current flightless birds ever flew or flew well, so they did not necessarily go from flying to not flying.
     
  12. Sep 23, 2010 #11
    I'm totally impressed by the great Replies, it was better than I hoped, and now have hours of reading.
    [A bit of levity, Madcap, the chickens saw the 'dead end' I am assuming you mean, so they started laying real crappy eggs to force us to do free range. By the time we are extinct they will soaring like pigeons. I wonder what Darwin would have thought of the pale yellow super store eggs?]
    One question, is it 'possible' one or more of the flightless birds is evolving towards flight? The penguins might want to consider it.
     
  13. Sep 23, 2010 #12
    hmmm...
    I was only going by a book from the 60's by Desmond Morris, The Naked Ape
    Wiki >
    Morris first came to public attention in the 1950s as a presenter of the ITV television programme Zoo Time,[2] but achieved worldwide fame in 1967 with his book The Naked Ape.[3] The book is an unabashed look at the human species, notable for its focus on humanity's animal-like qualities and our similarity with apes, and for explaining human behaviour as largely evolved to meet the challenges of prehistoric life as a hunter-gatherer. Reprinted many times and in many languages, it continues to be a best-seller.
    And there is this http://www.gate.net/~rwms/hum_ape_chrom.html
    """assembled a series of references and abstracts that document striking evidence for the common ancestry of humans and the great apes"""
    >>>> .like your the Mod and all so if its against the rules to say we are apes, I will stop.
    If there is info we are not, like you say, I would like to read about it, is there threads on that Topic?
     
  14. Sep 23, 2010 #13
    Not only are we descended from apes - we are apes.
    It's pretty likely that the ancestors of chickens once flew. The odds that all their ancestors back to lizards were flightless, and yet evolved feathers, chest bones, wings and beaks - all adapted to flight - but never flew is rather unlikely.

    Although the immediate ancestors of domestic chickens were ground dwelling fowl that if they flew at all it was probably limited to fluttering up into trees to sleep
     
  15. Sep 24, 2010 #14
    just for the record, pf Mentor changed the Topic from birds, flight, and evolution, to apes and man,,,,,
    as the OP I don't mind if it goes that way, as the leads for information I was looking for on THIS Topic came out.
    I would like to hear from others about whether we are monkeys or apes. It appeals to my curiosity. I cannot swear, but I am sure I heard Krauss and or Dawkins, in the You Tube discussions that led me to the Site, say we are apes....
    Dang.... it would take awhile to find those 'talks' again.
    I am sure IF Dawkins did say it, well then it would be OK! and class anybody disagreeing with him as an anti evolutionist.
     
  16. Sep 24, 2010 #15
    on this Topic, that is a statement which makes sense. That is the question I will be looking into from all of the great links supplied. If flightless birds are evolving towards flight, like all the other species did, that would make for a pretty good 'proof' of evolution.
    Notice on Wiki it 'conjects' that these birds 'lost' their flight ability, but it has the 'citation needed' sticker.
    """It's believed by some[citation needed] that most flightless birds evolved in the absence of predators on islands, and lost the power of flight because they had few enemies — although this is likely not the case for the ratites; the ostrich, emu and cassowary, as all have claws on their feet to use as a weapon against predators."""
     
  17. Sep 24, 2010 #16

    Evo

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    No, we are not descended from apes.

    Hopefully this makes it clearer to you.

    http://www.pbs.org/wgbh/evolution/library/faq/cat02.html

    It's too late to try to dig something else that sums it up clearly in a paragraph.
     
  18. Sep 24, 2010 #17
    So we're not apes, we are apoids? How spell semantics?
    Watch Dawkins call us apes.
    argue with him about it.

    and this>>>
    http://richarddawkins.net/articles/4121-elaine-morgan-says-we-evolved-from-aquatic-apes [Broken]
     
    Last edited by a moderator: May 4, 2017
  19. Sep 24, 2010 #18
    Eggomaniac, if I might try to help you to grasp what it is, it seems to me, that you are missing: I always think that the whole misunderstanding about the common ancestry of apes, of primates or of whatever other point you want to take in the complex phylogenetic structure has the wind taken out of its sails by this little astonishing evolutionary fact: There is powerful evidence, from microbiology, that human beings have a common ancestor with fruit flies. Now grasp it straight away, that common ancestor was neither fruit fly nor human. It might have borne no obvious morphological resemblance to fruit flies or human beings. And yet, whatever is common between modern fruit flies and modern humans – and there is a great deal more commonality between us than you might realise – existed in that common ancestor. There are any number of vastly different modern species who have a common ancestor, if you go far enough back down the evolutionary chain, but whose common ancestor would not belong to the modern classification of either modern species. So, the obvious morphological similarities between human beings and any other primate species is pretty powerful evidence that our common ancestor is much more recent than is human beings common ancestor with fruit flies. But that common ancestor still existed an awfully long time ago, and there is no accuracy at all in the idea that human beings are descended from any other modern primate.

    And the key point in answer to your original post was explained in close detail by DaveC426913 in post #9. You should pay very close attention to that post. It is a vital point to grasp that no evolutionary change that has ever occurred in any species did so with any specific purpose. Those that happened to give the organism a selective advantage have survived and propagated through the species by the process of natural selection. But penguins are evolving neither in the direction of flightlessness or flightedness. They have developed their superb ability to swim because of the powerful selective advantage that ability has in the environment in which penguins live. But none of the incremental changes that occurred in their ancestors did so with the specific goal of becoming such superb swimmers. Evolution can’t do that.
     
  20. Sep 24, 2010 #19

    DaveC426913

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    Worth repeating.

    You have no trouble understanding that the common ancestor of humans and fruit flies was neither. We did not descend from fruit flies.

    Likewise, the common ancestor of humans and apes was neither. We did not descend from apes.
     
  21. Sep 24, 2010 #20

    DaveC426913

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    This would astonish me.

    Are you suggesting that no ancestor of modern penguins could fly?

    I would bet a lot of money that no ancestral birds developed flight wings yet could not fly. It is only an adapation after the achievement of flight - and the extinction of any flightless prespecies - that birds found other niches where their flight withered.

    In fact, I'm not sure it makes sense to call the flightless precursors of birds 'birds' at all. They would be ... lizards. I submit that the definition of birds is that it is that precursorial line of lizards that did develop flight.
     
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