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Author | Topic: What you see with your own eyes vs what scientists claim | |||||||||||||||||||||||
Modulous Member Posts: 7801 From: Manchester, UK Joined: |
You've also combined it with your bizarre excuse that you won't bother with a citation because I wouldn't be satisfied with it. I don't recall you ever accepting that as a valid excuse from anyone. We disagree. You think a cite is necessary. I don't. I don't think the following really qualifies for requiring a citation in an ecology journal. a) there are learned behavioursb) there are unlearned behaviours c) the current consensus is that a complex (abe: unlearned!) behaviour that is efficient or optimum is almost certainly the result of evolution. Because these are general points, it is unlikely a single paper will go into them. They are found on a body of work that started with their respective pioneers, so any single cite is unlikely to do everything that you are demanding. I'd have to get a whole body of evidence together and compile into a convincing whole. Essentially to complete the task to my own satisfaction, let alone yours, would require writing a discussion paper or managing to find just the right one. For example, this paper states that
quote: but even that paper doesn't really cover it. You however do think it requires a citation. I think the statements are uncontroversial, pretty much the foundation of the work being done and accepted by the intended readers and so don't require citation. In fact, I think our positions and arguments are now out there and repeating them is surely a waste of time and memory, don't you? You think this presents a problem. I am not convinced by your argument that it is, you remain unconvinced by my argument that it isn't. Unless we have something new to say - let's not bother, eh? I have even offered concession on this point, yet you have decided not to take it. I offer again, let us grant that this was sloppy wording or improper citation and move on. Even if you were entirely right about this point, I don't see any thing particularly noteworthy. In a world of dodgy ethical practices, fraud, people talking about subjects clearly out of their field I feel we can discuss much more interesting things. So, any more examples to look at? Edited by Modulous, : No reason given.
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Modulous Member Posts: 7801 From: Manchester, UK Joined: |
For example, if your capability and behaviour changed as a result of ingesting a drug, would you say that was learned behaviour? Well, that really depends. Let me give you a straight answer in example form for ease, I would consider falling over when drunk to be unlearned behaviour. I would consider talking to a rock on acid to be a learned behaviour (though the impulse to communicate might be unlearned...but in both cases there is usually a complex web of learned and unlearned behaviour at work).
They fail to consider prey loss decreasing when a bird drops prey from a greater height. Why? Well, they might have considered it, but the proposal would run against the 'evidence of their eyes' - when birds drop things from higher up, it takes longer for them to retrieve them. Fortunately, in the spirit of science, they go observe it for themselves. They found that prey loss increases with height.
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sinequanon Member (Idle past 2865 days) Posts: 331 Joined: |
Well, that really depends. Let me give you a straight answer in example form for ease, I would consider falling over when drunk to be unlearned behaviour. I would consider talking to a rock on acid to be a learned behaviour (though the impulse to communicate might be unlearned...but in both cases there is usually a complex web of learned and unlearned behaviour at work). It sounds as if you agree that the new aspects of the behaviour are not learned. i.e what you could do after that you couldn't do before, is not learned. Agreed?
Well, they might have considered it, but the proposal would run against the 'evidence of their eyes' - when birds drop things from higher up, it takes longer for them to retrieve them. Fortunately, in the spirit of science, they go observe it for themselves. They found that prey loss increases with height. That was for one drop. The likelihood of the prey breaking also increases, so fewer drops would be needed. How do they know that wouldn't outweigh the benefit of shorter retrieval? Edited by sinequanon, : Changed 'longer retrieval' to 'shorter retrieval'
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riVeRraT Member (Idle past 416 days) Posts: 5788 From: NY USA Joined: |
Magicians do tricks all the time, and what we see isn't really what happened.
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Modulous Member Posts: 7801 From: Manchester, UK Joined: |
It sounds as if you agree that the new aspects of the behaviour are not learned. i.e what you could do after that you couldn't do before, is not learned. Agreed? On reflection I wouldn't say they were strictly speaking 'new', I'd say they were 'modified'. The same goes for brain damage I suppose. However, moving back towards the original point, where we were talking about a certain type of behaviour. I may not have mentioned it every time, but I tried to repeat it as much as I could stomach without sounding repetitive. And the behaviour in context was optimum or efficient behaviour, like the behaviour of the crows under discussion. I grant that it might be possible for a drug (or brain damage) to induce specific behaviour that is more optimum or efficient in principle, it is just highly improbable and definitely highly improbable if all the observed members of a seemingly random group exhibit the behaviour. If a bird scientist observed humans and thought it worth mentioning, with no evidence, that one possible reason that certain humans can play good poker is because they are on drugs or brain damaged - they would get an appropriately amused twitter I'm sure you'd agree.
The likelihood of the prey breaking also increases, so fewer drops would be needed. How do they know that wouldn't outweigh the benefit of longer retrieval? Finding this out was part of the test. They observed that the crows drop lower and more often when there are many birds around, and higher and less often as the number of birds decreased. As you say 'That was for one drop.', and that was what they were talking about 'one drop'. For each drop, the higher it is dropped from the greater the chance of breaking the nut but the higher chance of theft. The authors postulated that if natural selection was at play, or if the birds were able to learn how, the birds would have found some optimum. Edited by Modulous, : No reason given.
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Taz Member (Idle past 3292 days) Posts: 5069 From: Zerus Joined: |
riverrat writes:
Funny how you mentioned magicians. The people that they fool the most are scientists, you know.
Magicians do tricks all the time, and what we see isn't really what happened.
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Percy Member Posts: 22394 From: New Hampshire Joined: Member Rating: 5.2 |
sinequanon writes: The likelihood of the prey breaking also increases, so fewer drops would be needed. How do they know that wouldn't outweigh the benefit of shorter retrieval? You're thinking of a different question than the one they were actually attempting to answer. The question you seem to think they were asking is, "Does increasing drop-height increase the likelihood that they'll lose the walnut before they can break and eat it?" As stated in the excerpt you quoted in your Message 89, the question they were actually asking was, "Do crows adjust drop height with respect to potential kleptoparasitism?" I think your question is at least as interesting, but it definitely seems outside the paper's topic area, which was the factors affecting prey-dropping behavior, not the success-rate of various prey dropping strategies. --Percy
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Archer Opteryx Member (Idle past 3598 days) Posts: 1811 From: East Asia Joined: |
sinequanon: I would always believe the evidence of my own eyes. Then you are an atheist, because God, even by the accounts of theological "experts", cannot be seen. And you just told us you have no use for experts. Thank you for playing, Mr Non.
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sinequanon Member (Idle past 2865 days) Posts: 331 Joined: |
I grant that it might be possible for a drug (or brain damage) to induce specific behaviour that is more optimum or efficient in principle, it is just highly improbable and definitely highly improbable if all the observed members of a seemingly random group exhibit the behaviour. If a bird scientist observed humans and thought it worth mentioning, with no evidence, that one possible reason that certain humans can play good poker is because they are on drugs or brain damaged - they would get an appropriately amused twitter I'm sure you'd agree. Absolutely not. Performance enhancing drugs are very common in sport and games. It's one thing for which officials do look out. So this evolved/learned description that you called a dichotomy has now changed to something you think is only highly probable?
Finding this out was part of the test. They observed that the crows drop lower and more often when there are many birds around, and higher and less often as the number of birds decreased. As you say 'That was for one drop.', and that was what they were talking about 'one drop'. For each drop, the higher it is dropped from the greater the chance of breaking the nut but the higher chance of theft. The authors postulated that if natural selection was at play, or if the birds were able to learn how, the birds would have found some optimum. No. Read the conclusion. Their model predicts energy maximisation.
quote: quote: For kleptoparasitism they tested one drop, which does not test energy maximisation, and then said the results agreed with their model.
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sinequanon Member (Idle past 2865 days) Posts: 331 Joined: |
The question you seem to think they were asking is, "Does increasing drop-height increase the likelihood that they'll lose the walnut before they can break and eat it?" No. My point is that I do not see how the question they answered ties in with their conclusion that crows are maximising energy.
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Modulous Member Posts: 7801 From: Manchester, UK Joined: |
Absolutely not. Performance enhancing drugs are very common in sport and games. It's one thing for which officials do look out. We're not talking about improving physical traits through drugs, we're talking about adopting optimum strategies. What behaviour is changed to form some kind optimum way of running when a sprinter takes steroids?
So this evolved/learned description that you called a dichotomy has now changed to something you think is only highly probable? Yes, you've heard of tentativity right? We're talking science here; there's no need to list all the philosophically possible causes - just the ones that are actually suggested by the evidence.
No. Read the conclusion. Their model predicts energy maximisation. Yes, that is what their model predicts. What's 'no' about what I said?
quote: OK, so the paper says that crows drop lower when there are many birds around:
quote: And the paper also shows that the higher that walnuts are dropped the less drops it takes
quote: And the paper thus stated
quote: I also said
quote: And the abstract states:
quote: I'm not sure why that would prompt you to say 'no' and then tell me what part of the conclusion says.
For kleptoparasitism they tested one drop, which does not test energy maximisation, and then said the results agreed with their model. They didn't just test 'one drop'. They observed the rate of kleptoparasitism by measuring the rate of kleptoparatisism of the first drop of all the English walnuts at the Birch Lane site. If you think that this constitutes some kind of methodological issue then I'll happily hear you out. However, the data they did collect does agree with their model (mostly). The birds do take into account the chances that their prey will be stolen in selecting a height.
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Modulous Member Posts: 7801 From: Manchester, UK Joined: |
The likelihood of the prey breaking also increases, so fewer drops would be needed. How do they know that wouldn't outweigh the benefit of shorter retrieval? And then later,
My point is that I do not see how the question they answered ties in with their conclusion that crows are maximising energy. If a walnut has 100 energy, and the probability of losing prey looks like this:
And if the number of drops required looks like this:
Then the probability of still possessing the walnut after it cracks open:
So, on average, a walnut dropped at 5 metres nets 10 units of energy (10% of 100). Likewise, dropping the walnut from 1 metre will average out as 54 units for each walnut. The optimum height to drop is 2 metres, since each walnut then effectively gives 56 units of energy. If 2 metres is chosen then the subject has maximised the amount of energy they get from the walnuts. Obviously this is a simplified account, but that is how it ties into the idea that crows are maximising energy. Edited by Modulous, : No reason given.
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sinequanon Member (Idle past 2865 days) Posts: 331 Joined: |
We're not talking about improving physical traits through drugs, we're talking about adopting optimum strategies. What behaviour is changed to form some kind optimum way of running when a sprinter takes steroids? No idea. I do not think their purpose is to work on the brain or the nervous system. Drugs which do, alter behaviour.
They didn't just test 'one drop'. They observed the rate of kleptoparasitism by measuring the rate of kleptoparatisism of the first drop of all the English walnuts at the Birch Lane site. Semantics. We are agreed it can take many drops to break a nut and thereby obtain the energetic value. Their test took into account only one of them, i.e the first drop.
If you think that this constitutes some kind of methodological issue then I'll happily hear you out. However, the data they did collect does agree with their model (mostly). The birds do take into account the chances that their prey will be stolen in selecting a height. The number of drops required to break the nut was missing from their test as an independent variable. But it is a critical variable in measuring energy expended. Without it, their conclusion that the crows maximised energy with regard to kleptoparasitism is flawed.
And the paper thus stated quote:-------------------------------------------------------------------- For each drop, the higher it is dropped from the greater the chance of breaking the nut but the higher chance of theft. I can't find this "quote" anywhere in the paper by the way.
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sinequanon Member (Idle past 2865 days) Posts: 331 Joined: |
And if the number of drops required looks like this: Are these actual values? If so, which graph did you use and how did you work them out? Are you satisfied with your working?
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Modulous Member Posts: 7801 From: Manchester, UK Joined: |
No idea. I do not think their purpose is to work on the brain or the nervous system. Drugs which do, alter behaviour. Right, so we're back to
quote: Last time you disagreed because of performance enhancing drugs in athletics. I think we can now agree that a drug that makes you good at poker and a drug that builds muscle mass to increase speed/strength are different categories.
Semantics. We are agreed it can take many drops to break a nut and thereby obtain the energetic value. Their test took into account only one of them, i.e the first drop. They tested prey breakability. Their model predicted that the optimum strategy for harder nuts is to drop them from higher heights. The crows dropped harder species of nut from higher heights. They tested substrate hardness. They predicted that the optimum strategy for dealing with softer surfaces is to increase the height to drop from. It also predicted that the optimum strategy is to prefer harder surfaces. The crows dropped from higher onto soft surfaces and preferred hard surfaces. They tested the height of successive drops. They predicted that the height from which the walnut is dropped on successive drops will lower as the probability that the walnut will break goes up. They observed this behaviour in the crows.
quote: They tested prey mass and breakability. They predicted that the optimum strategy is to drop heavier walnuts from lower heights. The crows did not follow this behaviour. They tested prey loss. They predicted that as the risk of kleptoparasitism increases the optimum strategy is to lower the height to drop. This behaviour was replicated by the crows. Thus, with the exception of taking mass into consideration, the crows followed the optimum behaviour in adjusting height to account for various variables, maximising the chances of getting at the sweet nut, and thus maximising the energy per walnut.
The number of drops required to break the nut was missing from their test as an independent variable. But it is a critical variable in measuring energy expended. Without it, their conclusion that the crows maximised energy with regard to kleptoparasitism is flawed. The paper did not discuss the amount of energy the crow expends, though that would be interesting too. They were talking about the amount of energy gained from the walnuts.
I can't find this "quote" anywhere in the paper by the way. I was comparing my quotes with theirs to show how I didn't seen any contradiction with what I said with what the paper showed. Sorry for any confusion. Edited by Modulous, : No reason given.
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