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Diving spiders make their own gills - Comments

-troll-'s Avatar Comment 1 by -troll-

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Thu, 16 Jun 2011 04:55:16 UTC | #639089

Michael Austin's Avatar Comment 2 by Michael Austin

Site glitch, double post.

Thu, 16 Jun 2011 05:10:14 UTC | #639090

Michael Austin's Avatar Comment 3 by Michael Austin

Two questions:

  1. I'm going to put this on my Facebook, and there are some Creationists there(and I'm also curious). What is a plausible explanation for how this mechanism could have evolved?

  2. Is there any promise in making something like this for human use for extended driving?

Thu, 16 Jun 2011 05:11:11 UTC | #639091

Kim Probable's Avatar Comment 4 by Kim Probable

Comment 3 by Michael Austin :

  • I'm going to put this on my Facebook, and there are some Creationists there(and I'm also curious). What is a plausible explanation for how this mechanism could have evolved?

I was mulling over this earlier this evening. Hopefully somebody has a good idea - I'm really curious, too. =)

  • Is there any promise in making something like this for human use for extended driving?

There are rebreathers that scrub carbon dioxide from the air supply, though that isn't quite the same thing. It allows for recirculation of air so that somebody can stay under longer. It has a lot more risk than a regular SCUBA apparatus though, because there are more things that can go wrong. I'd imagine it'd be really hard to construct a membrane fine enough and tough enough to work the way this spider's bubble does.

Thu, 16 Jun 2011 05:50:54 UTC | #639093

Martin_C's Avatar Comment 5 by Martin_C

Comment 3 by Michael Austin :

Two questions:

  • I'm going to put this on my Facebook, and there are some Creationists there(and I'm also curious). What is a plausible explanation for how this mechanism could have evolved?
  • As it says in the article, 'Certain small bugs bob and dive into streams and rivers with the help of plastrons, trapped films of air that coat their bodies'. Surely it's not too hard to imagine that bugs that dove longer might have had access to more food or better shelter from predators and that small step-by-step changes in anatomy and behaviour might increase that film of air allowing longer dives. From there I don't think it's so hard imagine 'climbing Mt Improbable'. Of course this is just my imagination but I don't think it's the hardest riddle to come up with an answer to.

    Another example which has always flumoxed me is the behaviour of another species of spider which I forget the name of (sorry, I believe it's a variety of trapdoor). It lives in the desert where it digs a small hole inthe ground. It then goes off and collects multiple fragments of quartz crystal from round about which it brings back and arranges in a ring around it's hole. Next, it attaches a line of silk to each piece of quartz and retreats into the hole holding the end of each line. When an ant walks near the hole the quartz crystals transmit the vibrations of the ants footsteps down the line. The spider then jumps out for its meal. Amazing! Now how the heck do we get to that? I usually just think to myself about how long arachnids have been around and how short their generations are but can't imagine exactly how this could arise.

    Thu, 16 Jun 2011 06:22:45 UTC | #639098

    Michael Austin's Avatar Comment 6 by Michael Austin

    I can obviously see the advantage of this adaptation, but I can't imagine a step by step process that could generate this membrane which actually mimics the functions of gills, which themselves took millions of years to evolve. I know that one exists, I just need some help (preferably a further study) to imagine it.

    Please note that this is not an example of 'the argument from personal incredulity.' :) I really am just curious.

    Comment 5 by Martin_C :

    Comment 3 by Michael Austin :

    Two questions:

  • I'm going to put this on my Facebook, and there are some Creationists there(and I'm also curious). What is a plausible explanation for how this mechanism could have evolved?
  • As it says in the article, 'Certain small bugs bob and dive into streams and rivers with the help of plastrons, trapped films of air that coat their bodies'. Surely it's not too hard to imagine that bugs that dove longer might have had access to more food or better shelter from predators and that small step-by-step changes in anatomy and behaviour might increase that film of air allowing longer dives. From there I don't think it's so hard imagine 'climbing Mt Improbable'. Of course this is just my imagination but I don't think it's the hardest riddle to come up with an answer to.

    Thu, 16 Jun 2011 06:35:43 UTC | #639102

    Vicktor's Avatar Comment 7 by Vicktor

    Comment Removed by Author

    Thu, 16 Jun 2011 06:41:33 UTC | #639105

    Anonymous's Avatar Comment 8 by Anonymous

    Comment Removed by Moderator

    Thu, 16 Jun 2011 06:45:50 UTC | #639109

    Martin_C's Avatar Comment 9 by Martin_C

    Comment 6 by Michael Austin :

    I can obviously see the advantage of this adaptation, but I can't imagine a step by step process that could generate this membrane which actually mimics the functions of gills, which themselves took millions of years to evolve. I know that one exists, I just need some help (preferably a further study) to imagine it. Please note that this is not an example of 'the argument from personal incredulity.' :) I really am just curious.

    I can imagine that hairs and other fine bodily extensions would be able to trap air and that some bodies would be able to trap more air than others. The ability for the bubble created by the spider to absorb oxygen from the water is not some thing the spider evolved but just a property of a bubble underwater. It's a property that works to the advantage of the spider, but the spider has evolved to EXPLOIT the physical properties of oxygen and bubbles rather than evolve the ability to produce a specialised bubble membrane.

    Thu, 16 Jun 2011 07:23:06 UTC | #639120

    DavidMcC's Avatar Comment 10 by DavidMcC

    Comment 3 by Michael Austin :

    Two questions:

  • I'm going to put this on my Facebook, and there are some Creationists there(and I'm also curious). What is a plausible explanation for how this mechanism could have evolved?

  • Is there any promise in making something like this for human use for extended driving?

  • I can't be sure, Michael, but it looks to me as if it is holding a little web between its legs, in the manner of some species that still hunt by dropping their portable web, attached to forelegs (in the same manner as in this species) on the prey from above. This behaviour was shown on a David Attenborough program, but I cannot identify the species. If someone could, it might clarify how this spider's behaviour evolved. On the other hand, it could also have been an entirely independent evolution of related behaviour.

    PS, are you sure you meant "driving"? :)

    Thu, 16 Jun 2011 07:47:31 UTC | #639123

    Martin_C's Avatar Comment 11 by Martin_C

    Oh, and the name of the species of spider I mentioned in my earlier post is the 'corolla spider'. You can see them on youtube but I won't link you to the horrible Animal Planet clips there with the over dramatised american accent (you know, the voice that sounds like the movie trailer guy or a narrator for a chocolate bar commercial).. I have seen something with David Attenborough talking about them, much better.

    Thu, 16 Jun 2011 07:50:07 UTC | #639125

    Stafford Gordon's Avatar Comment 12 by Stafford Gordon

    Amazing!

    Thu, 16 Jun 2011 08:01:43 UTC | #639129

    JustLikeMyPops's Avatar Comment 13 by JustLikeMyPops

    Devious little buggers HaHa.

    Such tiny creatures but so clever, in fact, it's notable maybe how spiders in all their various forms are as a species pretty clever. I was talking to a friend and he mentioned how weird it is that spiders for the most part don't nurture their young, I'm guessing here as I have mental pictures of spiders covered in their young but also spider young left to hatch and wander off on their own, right? Anyway, I was a little drunk at the time but I found it amazing that the ability to build such a complex and devious structure as a traditional web wasn't nurtured into them by a caring parent but actually written into the creatures genes. I think another reason why spiders are scary is because they're too bloody clever =)

    Thu, 16 Jun 2011 08:47:49 UTC | #639145

    Anonymous's Avatar Comment 14 by Anonymous

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    Thu, 16 Jun 2011 09:01:55 UTC | #639154

    Aztek's Avatar Comment 15 by Aztek

    So god didn't create gills for a water spider which spends all its life underwater? Smart move there god, smart move.

    If god was an engineer for my company, I would have fired him a long time ago for incompetence.

    Thu, 16 Jun 2011 09:03:57 UTC | #639156

    Jumped Up Chimpanzee's Avatar Comment 16 by Jumped Up Chimpanzee

    Comment 3 by Michael Austin

    Is there any promise in making something like this for human use for extended driving?

    No. Humans need to breath so much oxygen that their air supply has to be compressed to approx. 200 bar or atmospheres on a standard full diving cylinder. Imagine how large a diving cylinder would have to be if the air it contained was not compressed!

    A similar structure as this web would have to be absolutely enourmous to catch enough air for human use, and so would be far too unwieldy and delicate to work at our scale.

    Thu, 16 Jun 2011 09:11:46 UTC | #639160

    DavidMcC's Avatar Comment 17 by DavidMcC

    Martin, I was thinking of something rather different from the Corolla spider, because Corolla spiders do not carry a little web between their feet, as far as I can tell. There is one type that does, but I still can't name it. Can anyone help?

    Thu, 16 Jun 2011 10:18:48 UTC | #639191

    Anvil's Avatar Comment 18 by Anvil

    Great article. Had my mind buzzing. So if oxygen is being diffused from the water, and nitrogen is leaking away at a greater rate, does the spider get an oxygen rush just prior to the collapse of the bell? How does it regulate for an ever changing oxygen/nitrogen mix? What are the depths involved? How does it deal with toxicity? How is this different from mammals - for whom oxygen is toxic below sea-level? Does it exhaust within this closed system - or outside of it?

    Damn. Gonna' have to learn about spiders, now!

    Comment 3 by Michael Austin

    Is there any promise in making something like this for human use for
    

    extended driving?

    We already remove oxygen from seawater for extended diving - dumping the unneeded hydrogen. Of course, on the surface, very similar electrolysers are working hard to keep the hydrogen for extended driving.

    The issue with these fuel cells is their efficiency. Not a problem if energy is abundant - hence a nuclear submarine has its range determined by food provision - pure air and water being manufactured on board.

    Anvil.

    Thu, 16 Jun 2011 10:29:05 UTC | #639201

    DavidMcC's Avatar Comment 19 by DavidMcC

    OK, I've just found a short article that suggests that I was mislead by the OP picture into thinking Argyronica aquatica uses a web attached to its feet: How Stuff Works

    "...Argyroneta aquatica... To build the diving bell, the spider first forms a web platform underwater, typically connected to a plant."

    Thu, 16 Jun 2011 11:08:52 UTC | #639217

    Martin_C's Avatar Comment 20 by Martin_C

    Comment 17 by DavidMcC :

    Martin, I was thinking of something rather different from the Corolla spider, because Corolla spiders do not carry a little web between their feet, as far as I can tell. There is one type that does, but I still can't name it. Can anyone help?

    Sorry there David, a little confusion - I was actually referring to an earlier post of my own. I was talking about a different spider.

    Thu, 16 Jun 2011 11:17:18 UTC | #639223

    Alan4discussion's Avatar Comment 21 by Alan4discussion

    Comment 13 by JustLikeMyPops

    Such tiny creatures but so clever, in fact, it's notable maybe how spiders in all their various forms are as a species pretty clever.

    I think the fact that they are small is very relevant. The volume to surface area ratio determines respiratory mechanisms. Large animals need lungs because they are large. With a small spider, and with the web providing a supporting framework for the surface tension of the water, the oxygen dissolved in the water will diffuse into the air bubble sufficiently quickly to replenish that used by the spider. CO2 would diffuse the other way.

    I am guessing here, but the initial evolution could arise either from the water level rising to engulf a web above the surface on protruding water plants, or bubbles trapped in a subsurface web providing a refuge for a diving spider.

    Spiders are very versatile and produce large broods of offspring from which nature selects. They can even use silk to fly long distances on the wind.

    Thu, 16 Jun 2011 11:42:36 UTC | #639235

    aquilacane's Avatar Comment 22 by aquilacane

    Comment 13 by JustLikeMyPops

    Such tiny creatures but so clever, in fact, it's notable maybe how spiders in all their various forms are as a species pretty clever

    Sorry to be a prick but I think clever is the wrong word. I doubt they put much thought into it. I would use evolved or adaptable. There are many insects that have adapted to gain advantage from the natural properties of water.

    Like the cat who evolved to bury his own shit, the bell spider has evolved to bring his own oxygen. Not clever just better for survival.

    Thu, 16 Jun 2011 13:07:17 UTC | #639259

    Marc Country's Avatar Comment 23 by Marc Country

    Hey Aquilacane,

    You should have looked up the definition of the word "clever".

    It means 'skillful or adroit in using the hands or body'.

    Misplaced pedantry's a bitch.

    Thu, 16 Jun 2011 13:45:28 UTC | #639272

    Southpaw's Avatar Comment 24 by Southpaw

    There is one type that does, but I still can't name it. Can anyone help?

    The brilliantly-named Ogre-Faced Spider carries a net that it pushes down on to its prey to snare them.

    When an ant walks near the hole the quartz crystals transmit the vibrations of the ants footsteps down the line. The spider then jumps out for its meal. Amazing! Now how the heck do we get to that? I usually just think to myself about how long arachnids have been around and how short their generations are but can't imagine exactly how this could arise.

    Spiders are all adept at detecting vibrations - many attach a special string of silk to their web, then lie in wait in a safe place, waiting to feel the vibration of something on the web travelling down the string. Male spiders also attract females for mating by strumming the web in a specific manner.

    Assuming that the forebears of the spider you mention were already 'set up' for vibration detection, it becomes easier to envisage a scenario whereby, in spiders living in an environment rich in quartz crystals, those crystals become involved in the prey detection process. If a spider happens to behave in a way that leads it to leave web strands around its burrow, and this causes it to detect more prey, than that tendency will be passed on and enhanced via EtNS.

    Thu, 16 Jun 2011 16:02:18 UTC | #639306

    Neodarwinian's Avatar Comment 25 by Neodarwinian

    Science. Always adding. Religion. Always subtracting.

    Thu, 16 Jun 2011 17:30:17 UTC | #639326

    ewaldrep's Avatar Comment 26 by ewaldrep

    This is truly amazing, how can anyone not be impressed or awed enough with which nature provides is beyond me!

    Thu, 16 Jun 2011 17:56:32 UTC | #639336

    Elisabeth Cornwell's Avatar Comment 27 by Elisabeth Cornwell

    This is just so cool.

    Fri, 17 Jun 2011 00:21:21 UTC | #639432

    Martin_C's Avatar Comment 28 by Martin_C

    Comment 24 by Southpaw :

    When an ant walks near the hole the quartz crystals transmit the vibrations of the ants footsteps down the line. The spider then jumps out for its meal. Amazing! Now how the heck do we get to that? I usually just think to myself about how long arachnids have been around and how short their generations are but can't imagine exactly how this could arise.

    Spiders are all adept at detecting vibrations - many attach a special string of silk to their web, then lie in wait in a safe place, waiting to feel the vibration of something on the web travelling down the string. Male spiders also attract females for mating by strumming the web in a specific manner.

    Assuming that the forebears of the spider you mention were already 'set up' for vibration detection, it becomes easier to envisage a scenario whereby, in spiders living in an environment rich in quartz crystals, those crystals become involved in the prey detection process. If a spider happens to behave in a way that leads it to leave web strands around its burrow, and this causes it to detect more prey, than that tendency will be passed on and enhanced via EtNS.

    Yes, the best scenario I can come up with is that some spiders were born with something in their genes which made them favour attaching their webs to hard white objects rather than, say, trees. In their environment those hard white things happened to be quartz crystals which improved the efficiency of the web because the spider can then detect vibrations from insects merely venturing NEAR the web rather than only those blundering into it, hence an advantage. It just seems like such a refined and perfected adaption, it must have been honed for so long! Afterall these spiders go out and select exactly the right pieces of quartz to use. Rather more specific and complicated than say a bird making a nest from just whatever it comes accross thats comfy.

    Fri, 17 Jun 2011 03:43:06 UTC | #639470

    12PM's Avatar Comment 29 by 12PM

    perhaps the majority of evolutionary processes are caused by mothers!

    I mean: most species are raised by mothers. There the imagination or thoughts of the mothers might involve in behavior change. And from that IMHO a new species emerges.

    the young spiders are raised by moms. The spiders I know stay in the nests and leave voluntarily. There they might learn something from their moms - apart from mothers' deliberate hormone doses (I don't know if the spiders do that way too).

    Spiders are natural great builders. They use their webs in all imaginable ways 'surprisingly'.

    Fri, 17 Jun 2011 05:46:38 UTC | #639483

    Michael Austin's Avatar Comment 30 by Michael Austin

    Has it been shown that an organism with such a small brain can have the capacity to learn? I'm reminded of the wasp who freaked out everything its auxiliary surroundings were moved.

    Comment 29 by 12PM :

    perhaps the majority of evolutionary processes are caused by mothers!

    I mean: most species are raised by mothers. There the imagination or thoughts of the mothers might involve in behavior change. And from that IMHO a new species emerges.

    the young spiders are raised by moms. The spiders I know stay in the nests and leave voluntarily. There they might learn something from their moms - apart from mothers' deliberate hormone doses (I don't know if the spiders do that way too).

    Spiders are natural great builders. They use their webs in all imaginable ways 'surprisingly'.

    Fri, 17 Jun 2011 06:31:58 UTC | #639491