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Thread: dino news: mummified dinosaur tail found in amber. Has ACTUAL 3D FEATHERY FEATHERS

  1. #26
    Member
    Registered: Feb 2002
    Location: In the flesh.
    Not necessarily. Birds fluff their feathers (make them stand out) often, particularly when preening or fighting. The goose bump effect could actually funnel air beneath and if moved back and forth work as a fan. Blood does indeed fill the long claws of finch feet so why not quill? I figure they survived and were successful for some of the same reasons we were and heat dispersal on the chase was damned important whether you were chaser or chasee. Endothermic depends on not overheating and damn near everything wanted to eat you.

    I think feathers could do all the things mentioned from shedding water which would cool too much to insulating when drawn flat and back to cooling whether with flapping of arms as chickens do or making them stand out and accept air flow. BUT what the devil was this tree branching feather thing for? That would seem to indicate drooping weight as for cold weather protection. Was there a temperature change at some point? When the earth cooled after the asteroid did they attempt adaption? Were there fluctuations as with the ice age then? This branching thing is a puzzle.
    Last edited by Tocky; 12th Dec 2016 at 22:53. Reason: things and stuff

  2. #27
    Moderator
    Registered: Jan 2003
    Location: NeoTokyo
    Just on the dating, this amber find is dated to 99 mya and other sites have feathered dinosaurs at 124 mya, twice as long as before the KP meteor. But I read the feathered dinosaurs were the ones best fit to survive the event in contrast to their non-feathered friends.

  3. #28
    Member
    Registered: Oct 2002
    Location: London / London / London
    The branching structure traps air for insulation. It's seriously not that mysterious. And the hunting/chasing thing, these were small, flighty and most likely insectivorous things we're talking about, not wolf analogues. Large-ish pursuit predators are not the first things you see with feathers, and seriously, raising feathers up like hot birds do is not more efficient at cooling than just not having feathers. Look at the major endothermic animals we've got today. Notice any constant, furry features? Is there anything alive that uses a fluffy skin covering to cool down?

    Feathers as cooling a) doesn't fit with how they're currently used, so you'd need novel evidence to support it as a hypothesis anyway, b) doesn't fit with what equivalent skin covering in mammals does, and c) doesn't scale like you would expect a cooling adapation to, bigger theropods (which would get hotter just due to mass vs surface area scaling) do not have more covering of feathers.

    The cooling adapations that might make more sense for what you're talking about, sustained locomotion etc, are more likely to be linked to the lungs. Theropods also developed a massive network of air sacs that helped ventilate their lungs (bird lungs are super wierd), which would definitely give them a highly vascularised, high-surface-area organ with good air throughout for heat exchange.

    Dema, latest work on KT impact event survival points at beaks and granivory probably being significant, there was a link in the other thread, hand on...
    Here you go, it's not open access unfortunately: http://www.cell.com/current-biology/...822(16)30253-6
    I can dig out a copy when I'm in the office next.
    Last edited by Vivian; 13th Dec 2016 at 10:37.

  4. #29
    Member
    Registered: Oct 2002
    Location: London / London / London
    Also in recent dino news, some undergrads did an analysis of whether or not you can hear a phone ringing inside a spinosaur: http://physics.le.ac.uk/journals/ind...ewFile/971/715

    Doesn't say where they got their metrics from though, 5cm of skin seems a lot?

  5. #30
    Member
    Registered: Aug 2004
    You are seriously hung up on the "fluffy" thing, when the whole point of examining the evolutionary pathway is precisely the fact that you need a blooded quill to get a fluffy feather, but do not need a fluffy feather to have a blooded quill. I'm not suggesting the proto-feather was a "fluffy radiator" on a small animal. I'm suggesting it started as a bare radiating quill on a large animal, then developed a fanning capability to aid in radiating heat. Later it would diversify into insulation, and eventually back into an air-moving structure.

    I mean, look at that amber sample. The bristles are closely aligned. Down is only like that at the top; fur isn't normally like that at all. It looks like it's evolving to insulation rather than from it.

    Here's a modern example of a large animal with a blooded, radiating, fanning structure used for cooling down:



    Bird lungs are fascinating, but it's a lot easier to see how they could have evolved from the need to supply a great deal of oxygen to a very large body, than to see how they could have evolved from a heat-dispersal capacity. The cross-current is more suited to heat retention. From a thermodynamics perspective, a captive air supply just isn't a good place to try to radiate even more heat into.

  6. #31
    verbose douchebag
    Registered: Apr 2002
    Location: Lyon, France
    I'm with Vivian on this. Not seeing feather-like structures at heat exchangers at all.
    They're nothing like large ears morphologically either, so no idea where that comparison comes in.

  7. #32
    Member
    Registered: Aug 2004
    Quote Originally Posted by faetal View Post
    Not seeing feather-like structures at heat exchangers at all.
    Okay. Why not?

    Quote Originally Posted by faetal View Post
    They're nothing like large ears morphologically either, so no idea where that comparison comes in.
    Insert Dumbo joke here. Really, you're going to have to elaborate, because I think I've made my point clear and I don't see either where you've missed it or where you're disagreeing with it.

  8. #33
    Member
    Registered: Oct 2002
    Location: London / London / London
    So you're mooting that feathers first evolved in multi-tonne theropods as blood-filled fan structures that they used to dump heat. Coelurosaurs don't start as giants, and there haven't been any large-bodied dinos found with feathers really at all. What you got in support?

  9. #34
    Still Subjective
    Registered: Dec 1999
    Location: Europops
    Interesting debate.

    Where do you stand on the "should we clone/raise from extinction" Viv?

  10. #35
    verbose douchebag
    Registered: Apr 2002
    Location: Lyon, France
    Quote Originally Posted by Pyrian View Post
    Okay. Why not?
    Because they are really quite awful at heat exchange. If they weren't, eiderdowns would be awful to sleep under.

    Insert Dumbo joke here. Really, you're going to have to elaborate, because I think I've made my point clear and I don't see either where you've missed it or where you're disagreeing with it.
    Elephant ears aren't branched and filamentous. Probably because if they were, they'd trap in too much heat. One of the most important aspects of heat exchange is rapid diffusion away from the site of heat exchange. Elephant ears are great because the entire plane of heat exchange is touching nothing but vast empty space, whereas with feathers, your heat would be exchanging in a billion different directions at once due to the lack of rigidity and a good amount of your heat would be heading straight back to where it came from, or transferred to an adjacent filament. The problem being that heat exchange works both ways, so you actually conserve heat that way (not infinitely, but probably would lose it more slowly than just having skin there). The best way to get rid of heat is to have a panel which sends it all off into general diffusion with the surrounding air, which allows for a better gradient for subsequent heat loss. Of course, a homeotherm like an elephant will also have some nice crafty mechanisms like vasodilation / vasoconstriction to determine how much heat exchange is going on in those ears. I doubt (will probably need Vivian to confirm) them dinos had such sophisticated stuff going on.

    It's all sounding a little specious at present. First up - what is the temperature data (cyclical if possible) for the region the animal was believed to be living in? Secondly, which feathered structures are still present for the purposes of exchanging heat with air?
    Last edited by faetal; 14th Dec 2016 at 15:17.

  11. #36
    verbose douchebag
    Registered: Apr 2002
    Location: Lyon, France
    Here is a simple list of things feathers are useful for: https://askabiologist.asu.edu/conten...tions-feathers

    Note that cooling down is only mentioned in the context of moving extremities out of feather coverage.
    This raises an interesting point which I guessed at earlier (though worded it atrociously). If dinosaurs were living in generally hot areas but they grew cold by night (which as anyone with a decent understanding of physiology can tell you, always hits the little guys harder due to the the surface area-to-volume heat loss dynamic), it would certainly be of benefit to have some insulating material which could be used in a specific posture to slow heat loss. In fact, the more I think about it, the more it's obvious that if it was a pressure to lose heat, the little dinosaurs would have less need of it than the bigger competitors, so that thought pushes me even farther in that direction.

  12. #37
    Member
    Registered: Oct 2002
    Location: London / London / London
    Quote Originally Posted by Pyrian View Post
    Bird lungs are fascinating, but it's a lot easier to see how they could have evolved from the need to supply a great deal of oxygen to a very large body, than to see how they could have evolved from a heat-dispersal capacity. The cross-current is more suited to heat retention. From a thermodynamics perspective, a captive air supply just isn't a good place to try to radiate even more heat into.
    Not the lungs, the air sacs. Big big surface area, tidal flow (the bit with the monodirectional flow is only the lung itself). Also, the air isn't captive, it definitely gets dumped into the environment (thats what the whole breathing out thing entails...). Air sacs = cooling is something I learned as dogma, I will admit, but the physics stacks, and here's some old data on pigeons (interesting actually, suggests they route air away from the actual lungs when they hyperventilate for cooling purposes, to avoid excessive CO2 loss): http://www.pnas.org/content/55/4/750.short

    So, you've got a cooling system that exists in modern dinosaurs (the air-sac system) and that there is also convincing evidence for in most theropods (http://www.nature.com/nature/journal...ture03716.html), and you've got an insulation system that exists in modern dinosaurs (feathers) that there is also convincing evidence for in many theropods (probably all coelurosaurs at least), and you're suggesting that the air-sac system didn't do cooling, and that the feathers didn't do insulation, instead they retained their developing form throughout their use-life, and they acted as radiators. Both of those are not parsimonious hypotheses. And then there is the whole volume/surface area problem and the lack of extreme feathering in big theropods. I think you've got something that's more of a speculation than a hypothesis, to be honest.

    I also can't find anything on heat loss from developing feathers, what you basing that on?
    Last edited by Vivian; 14th Dec 2016 at 07:27.

  13. #38
    Member
    Registered: Oct 2002
    Location: London / London / London
    Quote Originally Posted by SubJeff View Post
    Interesting debate.

    Where do you stand on the "should we clone/raise from extinction" Viv?
    For what, non-avian dinosaurs? There's Jack Horner's chickenosaurus thing (which is proper mad science, I'm not sure I agree with it: http://www.livescience.com/50886-sci...o-chicken.html), but otherwise it's not going to happen. For mammoths and stuff, I dunno - it's an interesting idea, and part of me thinks why not? But I'm dubious, there's loads of epigenetic stuff you'd miss... this is more neontology stuff really - Faetal, what's your take?

  14. #39
    Member
    Registered: Oct 2002
    Location: London / London / London
    Quote Originally Posted by faetal View Post
    Of course, a homeotherm like an elephant will also have some nice crafty mechanisms like vasodilation / vasoconstriction to determine how much heat exchange is going on in those ears. I doubt (will probably need Vivian to confirm) them dinos had such sophisticated stuff going on.
    eesh, no evidence in extinct guys for anything like skin vascularisation patterns (that I know of). But see above, living dinosaurs control heat loss by adjusting the ventilation rate of selected parts of their pulmonary system, which is sort of equivalent in terms of fluid flow control?
    Last edited by Vivian; 14th Dec 2016 at 07:52.

  15. #40
    Moderator
    Registered: Jan 2003
    Location: NeoTokyo
    Well while we're on the topic, I have a question that I'm sure I could answer with a 20 second Google search but I'm trying to rekindle this whole human contact thing so here goes...

    A few years ago I recall a popularish article that reported on a small tree-bound rat monkey-like creature which was important because it was right in the neighborhood of the line that would go on to become hominids, I don't remember how far back but it was in the millions to 10s of Ms of years ago, which was a humbling thing to read about since usually we're only told about past homo lines or at the furthest when humans and great apes separated, but we're almost never told about really ancient lines leading up to humans. So my question is, if I were to follow my ancestors back, what kind of creature might I run into say in the Jurassic Era? Doesn't have to be exactly, but in the ballpark. Is that kind of thing something we know anything about?

  16. #41
    Member
    Registered: Oct 2002
    Location: London / London / London
    Some sort of little shrew-like insectivores, most likely. Here's a Jurassic eutherian mammal (eutheria = placentals + marsupials): http://www.nature.com/nature/journal...ure10291.htmll
    They're claiming it's scansorial (tree-climber), but that's just based on limb proportions, so who really knows.


  17. #42
    verbose douchebag
    Registered: Apr 2002
    Location: Lyon, France
    Quote Originally Posted by Vivian View Post
    For mammoths and stuff, I dunno - it's an interesting idea, and part of me thinks why not? But I'm dubious, there's loads of epigenetic stuff you'd miss... this is more neontology stuff really - Faetal, what's take?
    With current tech, it doesn't seem doable. The DNA instability is really a big problem. As you say, things like DNA methylation / histone acetylation patterns are also likely to end up being knacked over time too. I guess if there was something prevalent enough where you had enough overlapping sequences to statistically identify errors, then maybe. It's tempting to think you have a proper snapshot when you see something so nicely preserved as body parts or whole insects in amber, but a great deal of macro structure is accounted for by slow-degrading proteins, so it's possible to get something which looks the business but is a molecular mess. I can't go into too much detail, but the sheer amount of bioinformatics analysis which the BIs where I work have to do just to ensure that knocking out a gene won't fuck up the splicing regulation for the entire region or mess with adjacent or overlapping mis-sense genes etc.. is pretty staggering. I'm thinking putting back together a genome with little to no reference material to correct against and avoiding some pretty funky dysregulation issues is a task so big I can't even see it. If the tech changes though, or we find something unexpected and well-preserved, then I don't see why not eventually. The question is who will pay for it.

  18. #43
    Still Subjective
    Registered: Dec 1999
    Location: Europops
    Oh, people would pay. If there was a realistic possibility of getting a full sequence people would pay.

    Can you tell which parts of the DNA structure are unstable/degraded or is it all completely unreadable?

  19. #44
    Member
    Registered: Oct 2002
    Location: London / London / London
    So best guess at the moment is that DNA has a half-life of 521 years, which means that after 7 million years or so it would basically be soup, even if it was perfectly preserved (bit of a pile of sand vs. sandcastle sort of vibe): http://www.nature.com/news/dna-has-a...f-life-1.11555

    Even with that as a max limit, how much breakdown do you need before the absolute best you can do is make a big ball of retarded dino-cancer? How much degradation of human DNA is incompatible with life?

  20. #45
    Still Subjective
    Registered: Dec 1999
    Location: Europops
    If any of it were useful, and you could tell the difference between real code and soup, you'd just need to sequence loads of it and jigsaw it.

    You only need a small amount of DNA degradation for incompatibility with life; I was thinking about assembling a proper full sequence.

  21. #46
    Member
    Registered: Oct 2002
    Location: London / London / London
    From the sound of it, there's absolutely no way you'd get even partial sequences of DNA from a non-avian dinosaur. Youd just have to make it up based on indirect evidence like skeletal anatomy etc, which is what the chicken mutant thing is supposed to be doing.

  22. #47
    Member
    Registered: Feb 2002
    Location: In the flesh.
    So cold weather brought flight. Our envy of it brought our own. Does that mean no flight by creatures on warm planets? No plane development then rocket to visit elsewhere? Only rockets were a development of wanting to kill something far away so as long as other creatures want long range kills they could still develop them on warm planets. Ergo stay away from creatures from hot worlds come for a visit. Naturally I'm being facetious. All the speculation does bring out info though. Thanks for that.

    Sigh. Sad that we will never know the full historical rendering of evolution. Not that we would have long enough a life to view it even one frame per development anyway. And if we want to make Godzilla to eat a city we will just have to make the entire thing up from chicken bones.

  23. #48
    Member
    Registered: Feb 2008
    Location: on a mission to civilize
    Enough of this discourse. You all know that God put those feathers there to fool us. FOOL US, I SAY!

  24. #49
    verbose douchebag
    Registered: Apr 2002
    Location: Lyon, France
    Quote Originally Posted by Tocky View Post
    So cold weather brought flight.
    Only if you ignore non-avians which can fly. Convergent evolution and that.

  25. #50
    Member
    Registered: Oct 2002
    Location: London / London / London
    Speaking of, I'm not sure enough people know about this weirdo: http://onlinelibrary.wiley.com/doi/1...6.01105.x/full

    Sharovipteryx, the first (only?) rear-winged glider:


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