Naked Science Forum

General Science => General Science => Topic started by: Searcher on 14/01/2006 12:25:36

Title: How does a spider know how to make a web
Post by: Searcher on 14/01/2006 12:25:36
How does a spider KNOW how to make a web[?] No living creature is born with  knowledge[:0] and the spider is not taught as it is born alone, so how does it build a complex piece of engineering without any prior knowledge.
Title: Re: How does a spider know how to make a web
Post by: Simmer on 14/01/2006 17:33:17
quote:
Originally posted by Searcher

No living creature is born with  knowledge[:0]


Is that the necessarily true?  I can't think of any fundamental reason why the genome should not contain survival critical knowledge as well as other information.

I had a quick rummage through the internet after reading your question and most sites tend to call this kind of thing "instinctive behaviour patterns" - but, as you imply in your question, some of these seem to require a good deal of information to work.http://www.a2zpsychology.com/psychology_guide/instinct.htm
Title: Re: How does a spider know how to make a web
Post by: Dr B on 14/01/2006 17:57:29
Is this not simply natural selection?  It is not a learnt skill but a behaviour.  It is in the genome.  Amongst a group of spiders making webs some will be better than others, more likely to feed and so live long enough to reproduce. These will pass on the genes that control that behaviour.  

So the question becomes are there genes for web making, nest building...  And then we have to be careful because a learnt skill such as solving a rubik cube is not part of our genome - but what about being a good driver.  Well I guess that hand eye coordination is part of our genome.

An interesting question must about the first webs.  This is where it gets interesting.  How does a new behaviour appear ...


Dr B
Istanbul
Title: Re: How does a spider know how to make a web
Post by: Searcher on 14/01/2006 19:01:27
Thanks Simmer,

I had a look at the web site but cannot believe that the amount of information required to build a complex web can be stored in the DNA at birth.[:0] Instinctive behaviour alone is not enough.

I thought that instinct was more of a reflex action than inborn knowledge. If we were born with knowledge then we would know at birth all that our parents knew at the time of conception. It appears that this is true for the spider or is it.

Quote from the web site “Most instinctive behaviour is released (brought about) by a stimulus, something that makes the animal act as it does.”

Try This:[;)]

Does every living creature have access to a cosmic library and by using the right stimulus can down load this information into its DNA and hence have the knowledge to act as it does.[?]

The Mind Boggles
Title: Re: How does a spider know how to make a web
Post by: Soul Surfer on 14/01/2006 23:00:01
You may think that a web is a complicated thing but it can probably be broken down itho a relatively small number of simple logical operations.  The algorithms that most genes use are remarkably simple but can lead to incredibly complex behaviour.

Learn, create, test and tell
evolution rules in all things
God says so!
Title: Re: How does a spider know how to make a web
Post by: another_someone on 15/01/2006 01:54:20
quote:
Originally posted by Dr B

An interesting question must about the first webs.  This is where it gets interesting.  How does a new behaviour appear ...



I am not sure that this really is that complicated.

Firstly, most things that a living organism uses started out as something else.  Birds feather started out as a means of keeping the animal warm, before it started to use them to fly with.  Similarly, the silk spiders use have numerous purposes, from building cocoons to building small sails that allow very small spiders to drift in the wind.  Then it just comes to the point where a spider starts building the right kind of grids, and it has a web.
Title: Re: How does a spider know how to make a web
Post by: ukmicky on 15/01/2006 02:32:41
The same way as a turtle heads for the sea. Its a natural survival instinct, a memory which doesn't have to be learnt.   Its automatically copied over into every new generation but can be upgraded and changed through genetic flaws, new instructions , additions to the program and with the help of natural selection,which is natures way of deciding  whether its a worthwhile addition to keep.
Does that make sense[:)]
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Title: Re: How does a spider know how to make a web
Post by: another_someone on 15/01/2006 02:43:11
quote:
Originally posted by ukmicky

The same way as a turtle heads for the sea. Its a natural survival instinct, a memory which doesn't have to be learnt.   Its automatically copied over into every new generation but can be upgraded and changed through genetic flaws, new instructions , additions to the program and with the help of natural selection,which is natures way of deciding  whether its a worthwhile addition to keep.
Does that make sense[:)]
Michael                 HAPPY NEW YEAR                    



I don't think a turtle actually heads for the sea, it heads for that which is bright under moonlight, which happens to be the sea.  It has the effect of heading for the sea, but I don't believe the underlying behaviour has any concept of sea, or even of water.  It is no different from a moth to the light.
Title: Re: How does a spider know how to make a web
Post by: ukmicky on 15/01/2006 02:56:32
HI GEORGE
if that were true it wouldn't really matter because its still a natural instinct telling it what to do.

and or a really big but if i may, not all turtles hatch out during the hours of darkness some late stragglers hatch out when its light and still head for the sea.

Michael                 HAPPY NEW YEAR                     (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Fparty-smiley-012.gif&hash=844994fd61764508c533537d6874634d)
Title: Re: How does a spider know how to make a web
Post by: another_someone on 15/01/2006 03:21:58
quote:
Originally posted by ukmicky

if that were true it wouldn't really matter because its still a natural instinct telling it what to do.



Indeed, it does not matter.  All I was trying to highlight that that which we see as complex intelligence is often a very crude process.

quote:

and or a really big but if i may, not all turtles hatch out during the hours of darkness some late stragglers hatch out when its light and still head for the sea.




I think even then, assuming it is not overcast, the sea would still be the brightest area beneath the sky.
Title: Re: How does a spider know how to make a web
Post by: Searcher on 15/01/2006 11:48:39
quote:
Originally posted by ukmicky

The same way as a turtle heads for the sea. Its a natural survival instinct, a memory which doesn't have to be learnt.   Its automatically copied over into every new generation but can be upgraded and changed through genetic flaws, new instructions , additions to the program and with the help of natural selection,which is natures way of deciding  whether its a worthwhile addition to keep.



If this is true what differentiates between instinct memory and learnt memory.[?] Why doesn't learnt memory become instinct memory and passed on to its offspring.[?]

We know this is not true in higher forms of life because we are not born knowing E=MC^2 we have to be taught that. Which brings me to: where does the original knowledge or idea come from in the first place.[?]

Was it always there waiting for someone to pick it up, or was it created by a figment of someones imagination.

By the way don't you guys ever sleep.[:0]
Title: Re: How does a spider know how to make a web
Post by: another_someone on 15/01/2006 12:37:14
quote:
Originally posted by Searcher

If this is true what differentiates between instinct memory and learnt memory.[?] Why doesn't learnt memory become instinct memory and passed on to its offspring.[?]



What you are talking about is Lamarckism.  Except in a few special cases, it is not considered the primary means of inheritance, although it was a popular theory in early 19th century.

The difference between instinct memory of memories learnt within one's lifetime is the period of time over which the are learnt.  To learn something within your life could take you a few minutes or hours.  To learn something that will be inherited from one generation to the next will take several generations to learn.  I suppose you could argue it is a manifestation of the tendency that if you want something to last longer, you need to spend more time constructing it.

quote:


We know this is not true in higher forms of life because we are not born knowing E=MC^2 we have to be taught that. Which brings me to: where does the original knowledge or idea come from in the first place.[?]

Was it always there waiting for someone to pick it up, or was it created by a figment of someones imagination.




E = MC^2 is a mathematical expression, and mathematics is a language.  This kind of knowledge is about understanding the world through language, whether it be the language of mathematics, or some other language.  Such knowledge came into existence when someone invented the language, and was just waiting for someone to discover that the language could express such an idea, and then realise that this expression of an idea looks like the world around them looks like.

I suppose what could be said is that while we were not born knowing E=MC^2, we were born with an idea of how to use language, even if that does not extend to being born with one particular language, but rather to be able to learn many different languages.

quote:


By the way don't you guys ever sleep.[:0]



We are kind of a bunch of insomniacs – some of us more than others – you just have to read Neil's posts on his insomnia problems – makes my sleeping habits look positively well disciplined.
Title: Re: How does a spider know how to make a web
Post by: Searcher on 15/01/2006 14:02:27
quote:
[The difference between instinct memory of memories learnt within one's lifetime is the period of time over which the are learnt.  To learn something within your life could take you a few minutes or hours.  To learn something that will be inherited from one generation to the next will take several generations to learn.  I suppose you could argue it is a manifestation of the tendency that if you want something to last longer, you need to spend more time constructing it.



My great great great  grandfather was a very famous scientist.
I was not born with his knowledge I had to be taught it like anyone else. My daughters although they have heard of him, don't know  much about his theories  having not been taught science to that extent. They only know what I have told them.

Like my grandfather I have studied science, chemisty / physics, (not his subject) and was always taught to keep an open mind. I was once told never accept anything you are told as the absolute truth and only believe half of what you see as the truth.

If what you say and believe is true, then Inherited memory takes not several generations to aquire but thousands of years and then if at all. Evolution is a very slow process. It appears that the higher the life form the slower the process and the more it relies on learning from others. We are less reliant on instinct than our ancestors to survive so if we don't use it we loose it I suppose.

I still believe there is a missing factor somewhere hidden in the DNA that we haven't discovered yet. So I ask questions and get the opinions of others to get somewhere near the truth.

Yes the truth is out there, but the point is will we able to recognise it as such when we see it.

Title: Re: How does a spider know how to make a web
Post by: ukmicky on 15/01/2006 15:34:19
quote:
If this is true what differentiates between instinct memory and learnt memory. Why doesn't learnt memory become instinct memory and passed on to its offspring.


because its in your gene's, and as you said

" I still believe there is a missing factor somewhere hidden in the DNA that we haven't discovered yet. "

its like a imprinted memory that is held within your DNA,  and only evolution and natural selection change it.

And just out of interest who was your grandfather Searcher

Michael                 HAPPY NEW YEAR                     (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Fparty-smiley-012.gif&hash=844994fd61764508c533537d6874634d)
Title: Re: How does a spider know how to make a web
Post by: neilep on 15/01/2006 17:51:39
quote:
Originally posted by Searcher

How does a spider KNOW how to make a web[?] No living creature is born with  knowledge[:0] and the spider is not taught as it is born alone, so how does it build a complex piece of engineering without any prior knowledge.



All baby spiders receive tutoring in how to make webs in Spidergarten.[:)]

Men are the same as women.... just inside out !!
Title: Re: How does a spider know how to make a web
Post by: another_someone on 16/01/2006 01:48:29
While we're on the subject of learning and knowledge/information.

The immune system is capable of learning.

Bacteria can pass plasmids between each other, so a bacteria that has developed tolerance to an antibiotic can teach another to tolerate antibiotics bacteria by passing a plasmid to the other bacteria that contains the code for antibiotic tolerance.
Title: Re: How does a spider know how to make a web
Post by: another_someone on 16/01/2006 01:59:55
quote:
Originally posted by Searcher

My great great great  grandfather was a very famous scientist.
I was not born with his knowledge I had to be taught it like anyone else. My daughters although they have heard of him, don't know  much about his theories  having not been taught science to that extent. They only know what I have told them.

Like my grandfather I have studied science, chemisty / physics, (not his subject) and was always taught to keep an open mind. I was once told never accept anything you are told as the absolute truth and only believe half of what you see as the truth.

If what you say and believe is true, then Inherited memory takes not several generations to aquire but thousands of years and then if at all. Evolution is a very slow process. It appears that the higher the life form the slower the process and the more it relies on learning from others. We are less reliant on instinct than our ancestors to survive so if we don't use it we loose it I suppose.

I still believe there is a missing factor somewhere hidden in the DNA that we haven't discovered yet. So I ask questions and get the opinions of others to get somewhere near the truth.

Yes the truth is out there, but the point is will we able to recognise it as such when we see it.




You did not inherit the detailed knowledge (i.e. the language of science) from your grandfather, but it is clear that you did inherit the inquiring and sceptical mind of your grandfather.

You would not want to inherit the detailed knowledge of your grandfather, because the knowledge gained by science changes from year to year.  If you were born with that knowledge built into you, then the pace of change of science would grind to a crawl.

You say we are less reliant on instinct – insofar as we have a far more complex learning capability, this is true; but beneath that, if we lacked instinct, we would be no more than computers without a computer program – very capable, but unable to apply that capacity.
Title: Re: How does a spider know how to make a web
Post by: LawnBowler on 08/02/2006 14:56:51
Juvenile spiders are able to build perfectly good webs. However, in some species adults refine their webs according to experience.
Title: How does a spider know how to make a web
Post by: arkaneivories on 25/06/2009 10:03:43
Hi, I had the same question as the original poster after observing a spider build its web outside a window.

To me, it really is hard to grasp that such a seemingly difficult process could just be naturally, genetically, instinctual. How every spider would "know" to go about this process (http://en.wikipedia.org/wiki/Spider_web#Formation). I get what people are saying about some instincts like the turtles and fish etc., but this is significantly more complex than that. Any human attempting this kind of feat would need a very detailed instruction booklet.

Until I see someone in glasses and a white coat with a stethoscope tell me otherwise, I think I'm going to have to take a slightly different stance, saying that a lot of this information on how to adequately make these kinds of structures is observed from things like the mother's nest where the spiderlings are born or the nests of other spiders lying around.