Instinct - evolved or better answer?

On a number of threads I've seen people suggesting that instinctual practices (the building of certain kinds of nests, etc.) are too complex to have arisen out of natural selection.Then the other day I saw a little dog climb his back legs up a tree trunk in order to pee higher. It's not the first time I've seen this. It's always a small dog, though not always the same species.What occured to me was this - this behavior in this little dog could not have "evolved" since it's doubtful that the breed had existed long enough for such an occurance. Likewise, it's doubtful that the breeders were selecting for "high tree peeing".So why have I see so many little dogs do this?I suggest that it's as much an engineering problem as one of biology.Given a certain set of tools and a certain goal, chances are most participants are going to solve the problem the same way.A weaver bird doesn't need to evolve the "weaver nest" as though it were some blueprint stamped on the mind. It only needs to evolve the ability to weave reeds, the tendancy for curves, and the desire for a nest which is big enough to support it's weight. Given the simply programming for next building, the outcome is generally the same.Computer scientists have shown that with very little code they can make tiny robots which behave like insects. You don't need very many commands to create complex behavior.I'm not suggesting that no behavior / instinct is the result either directly or indirectly of evolution.What I am saying is that - if a little dog wants to pee higher than the other dogs, there's only one was he's going to do it.Thoughts?

Thread moved here from the Proposed New Topics forum.

I take it here that you're proposing that cultural transmission (i.e. teaching / observing) is not a mechanism. I can fish around for information, but as far as I can tell, in many behaviors such transmission is not necessary.Given that, then there's one question I didn't feel you addressed accurately. I can accept the "it's an engineering problem" stance, save for one aspect--why aren't there large numbers of weaver birds who fail to solve the problem? You haven't given a compelling reason why the birds solve the problem at all.What is necessary for weaver birds to be able to solve the problem? Surely having the tools is not enough. What cognitive capacities are found that connect the tools and resources with the final product?I don't have the answer, but I think it's important in giving a full story about innate abilities.Ben

Good question.I would suppose that this is where natural selection kicks in (futher blurring the engineering/evolution line). Obviously a bird who fails to build the nest isn't going to have a place to lay the eggs.I don't know how you'd measure this outside of the lab. We'd have to look for the nests that weren't built - hard to do.I'm not saying that evolution didn't play a role in these behaviors. I strongly believe that it did. What I'm suggesting is that, in the case of the weaver bird, all that's needed is - 1) A desire to build a nest, 2) the availability of grasses, 3) the ability to weave the grasses, 4) the birds morphological restrictions (ie the bird needs a nest X big, it's head tilts Y degrees left or right, etc). and 5) -speculative- a desire for a hanging nest as opposed to one that sits on the branches.I'd be interested to know if weaver birds hand raised from eggs will build weaver-type nests. I suspect they will.

Right. So that's what we're trying to figure out. And I think it's a good question to ask. Right. So I think we agree, the (assumed) facts that 1. the birds show nest-building without teaching and 2. we don't see numbers of birds failing to build nests are important data points in determining what "innate" mechanisms are used. I think there's one that you're missing, having to do with (part of)#4 (that a nest must be X big): birds must have some mechanism for taking their size into account. Do birds "realize" that they're "just so" big? I guess so, we don't see birds trying to fit through cracks that they can't fit through, and we don't see birds making nests the wrong size (too big, too small). Maybe we can add this "knowledge of size of self" as 4a).1) and 5) seem ... "innate" to me. I'd also put "desire" in quotes, but that doesn't really matter.The big questions I have are,

1. where does 3) come from?
2. Do we need a "6) ability to make a nest"? Seems to me 1) - 5) are good enough to make a "great weaved wall" of grass, a "leaning tower of gras", or a "grass-effel tower" Or another way to think of it, maybe 1) isn't enough. You might want to make a nest, but maybe you only know how to make a grass coaster. Great for guests, but...

I do agree with your overall point that we don't have to do wholesale attribution, that small parts add up to large effects. I'm not trying to challenge that point, only to see if we can push towards finding what small parts are reasonable to suggest.If I actually had real time, I'd do some reading on this behavior. Especially 'cause everything I study asks this question--what are the minimum sets of pieces necessary for a behavior, and how does that relate to hardware?BenThis message has been edited by Ben, Sunday, 2005/11/27 08:58 AM

is a nest of grass fundamentally different than one from sticks?a robin's nest is often grass plastered with mud, but can also be sticks used the same way.stick nests need to be interlocked to keep from falling apart, and this is often accomplished by both pocking sticks in and pulling on some to rearrange themdealing with grasses could easily start with reeds that are stiff and gradually working down to the more flexible materials, where more time is spent pulling into place than pushingonce you are pulling and looking for maximum interlock, all you need to do is alternate sides ... weaving.as for hanging, that could easily be a means to avoid predators that have to remain on tops of branches, as would being able to move out to the ends of flexible branches instead of staying in the crotches.And if the bird builds the nest around itself then it will fit eh?

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RebelAAmerican.Zen[Deist
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RAZD, good thoughts. Let's put them more in the perspective of what mechanisms are being postulated to be "innate" That's true. It sounds to me that you're proposing the "nest building" ability / behaviors (as described) are "innate"? Where does this knowledge of their predators come from? Does every bird need to learn to build the nest from the inside? I doubt we'd see puzzled birds, building nests the wrong size from the outside. I guess "standing inside to build" is part of the nest-building program?I'm asking the questions not as proposals; I really have no idea. I'm just trying to frame your ideas within the topic, and see what questions fall out.Ben

No, just that they have developed over time. Many birds nest on bare ground - heck look at penguins - nests just offer more varieties of protection and dealing with environmental changes ... and freedom for the parents to forage for food. Seeing it happen. Having a nest robbed while the parents can only watch or pester to no effect. They can survive even if the eggs\offspring don't. Many first year birds build several nests before getting one that is used, and in many bird species the males build the nests to attract the females who inspect them for suitability. You will also see birds get in and "final fit" nests with the lining material for a good snug fit. That packing on the inside can make all the difference eh?Wanna get lucky? Build a good nest.

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we are limited in our ability to understand
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RebelAAmerican.Zen[Deist
... to learn ... to think ... to live ... to laugh ...
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I think the dog and the bird are two different mechanisms. As far as I can remeber from my comparative psychology (all those years ago!).I recall birds would use Fixed Action Patterns for some of their behaviour. When you kick an egg of the Greylag Goose out of its' nest the bird will dutifull use its' beak to roll the the egg back into the nest. Now, if you are an even bigger meany and pick the egg up, the goose will keep rolling a non existant egg as if the egg were still in its' field of view.The behaviour is a fixed action pattern that does not change, a bit like our startle reflex. Once it's 'fired' it will go on to completion. No learning there.Based on this flimsy memory over 10 years old I would say that the birds nest IS hard wired. I don't see why the nest building behaviour cannot modify by experience, but the 'build nest here' imperitive is probly hard wired.Dogs on the other hand have 'looser' wiring and can social learn too. I have read about cunning little black bears scampering up snow difts to 'mark' their trees too.This brings me to my final flimsy memory: Preparedness. This (as I recall) is a species' predisposition towards learning 'things'. Humans' is language and facial recognition (among others), cats is stalking, song birds singing etc. the bear bones of the behaviour is there, but learning via the gift of experience fine tunes it to react to the environment.So there you have my ultimate cop out answer: a species has some level of hard wired behaviour such as jumping in fright or shock, to an experience modifide behaviour such as modifying the startle reflex into 'combat reflexes' of a trained soldier.

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Many first year birds build several nests before getting one that is used, and in many bird species the males build the nests to attract the females who inspect them for suitability. You will also see birds get in and "final fit" nests with the lining material for a good snug fit. That packing on the inside can make all the difference eh?

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Wanna get lucky? Build a good nest.

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You beat me to it. The weaver bird is one of those where the male builds the nest and the females inspect and choose.I guess if the guy never gets it right, he never gets any, and his line ceases.

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Nobody can make you feel inferior without your permission. -Eleanor Roosevelt-

The bower bird (bowerbird?) does remarkable building.The male builds a "bachelor pad" and decorates it and the surrounding area with brightly colored objects (blue is favored). He buzzes and dances about to attract a female, and if she approves of his bower, she will enter it, and he will get lucky. Then she flies off, builds a nest, and raises the young on her own.The younger males almost never get lucky. Older males may mate with a dozen or more females each season. Younger males will steal another's decorations or demolish their bower, though the older males rarely do. The males are both exacting and idiosyncatic in their bower building, quickly spotting any observer-added material and removing (or relocating) it to their satisfaction. Some of the bowers are quite striking, and no two are exactly alike.This message has been edited by Omnivorous, 11-28-2005 11:35 AM

In addition to what others have pointed out related to nestbuilding, there are also bird species that do not build nests. Instead, they have come up with a variety of potential solutions. Penguins use their feet. Others steal existing nests that other species have built. Still others simply stick their eggs in with those of some other species and let the surrogate raise their young. And yet other species just dump the eggs on the ground. Some, such as the Osprey, eagle and many owls, build a nest that they return to year after year. They modify and repair it but continue to use the same basic structure as long as it's available.

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Aslan is not a Tame Lion

how do you program hard-wird responses? how do they come to be in the first place?

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we are limited in our ability to understand
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RebelAAmerican.Zen[Deist
... to learn ... to think ... to live ... to laugh ...
to share.

and they've learned to mimic the sounds of cell phones ...

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we are limited in our ability to understand
by our ability to understand

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RebelAAmerican.Zen[Deist
... to learn ... to think ... to live ... to laugh ...
to share.

I've got no time now, but check this link out. It's pretty interesting and has some good info. I will get back to you on this one.Please note it's from a university (Plymouth UK) web site so it's not in too much depth, and it's a teaching aid for undergrads.http://salmon.psy.plym.ac.uk/year1/ETHEXPT.HTM#overview http://www.psy.plym.ac.uk/year3/psy364criticisms...Edit: added second link and message clarity.This message has been edited by Larni, 11-30-2005 10:23 AM fixed diplay of url to change page width - The QueenThis message has been edited by AdminAsgara, 12-05-2005 09:46 PM