Perception

[Mike Connor]

PS. In the quoted study, the perception involved is related to what the fish can sense in the water, and in this case is not visual, but might be loosely described as "scent", or "olfactory stimulus".

http://en.wikipedia.org/wiki/Olfactory_system

http://www.sciencedirect.com/science/ar ... 8207000536

http://scholar.google.com/scholar?q=olf ... CBkQgQMwAA

Also of interest;

http://en.wikipedia.org/wiki/Perception

TL
MC

[overmywaders]

hank,

One other point which follows from what Mike and I are saying is that some extrapolation of results always occurs. In other words, an experiment performed on 6" rainbow trout will be quoted by authors of a later study of trout behavior to be applicable to 8" rainbow trout as well. They may even suggest that 12" rainbow trout have the same capability. Until a study is done using 12" rainbow trout, the extrapolation of results from the 6" rainbow trout experiments will usually be considered valid in peer review.

However, except for certain gross behaviors known to be common to all trout - daily feeding periods for example - scientists seldom pass proven attributes from species to species. Thus, they wouldn't assume that a brown trout in a meadow stream will feed at the same time as a rainbow trout in fast water. (There have been some great studies done on this subject and the trout do feed at different times/water temps.)

As to the capability of trout, I agree with the saying "... not sufficiently evolved to burp"; but at the same time appreciate the incredible ability of fish to instinctively and/or through acquired knowledge, discriminate within their own environment. Imagine, brown trout parr that came from a batch of eggs, can identify their siblings among parr from other batches. http://beheco.oxfordjournals.org/conten ... 5.full.pdf

Or the ability of brookies to adapt in color to their background within 11-12 weeks. http://www.tandfonline.com/doi/abs/10.1 ... 2.3.CO%3B2

It is a fascinating world and its creatures are equipped with myriad survival abilities! That is what makes fishing challenging.

Regards,
Reed

[Mike Connor]

The degree and relationship of some obviously correct extrapolation is described in that study;

QUOTE

4. DISCUSSION
Our results suggest that fathead minnows conditioned to
recognize the odour of lake trout generalized their
recognition to closely related species, the brook trout
and rainbow trout, but not to distantly related predatory
(pike) or non-predatory (sucker) fish. The absence of
response to the sucker odour indicates that minnows did
not rely on diet cues to generalize their recognition. The
absence of a response to pike odour indicates that the
generalization is limited to trout only, but not all fish
predators. As expected, minnows responded with the
highest response intensity to the odour of lake trout,
the species they were conditioned to recognize as a threat.
The level of generalization was dependent to some extent
on the degree of relatedness of the other potential
predators to the reference predator. Minnows did not
respond differently to lake trout and brook trout, but the
p values for both behavioural measures (0.065, 0.067)
indicate that we may have weak support to say that
minnows chemically differentiated the two species. We
also have evidence suggesting that minnows responded
with less intensity to rainbow trout odour than brook trout
odour, hence displaying a graded response to other
trout odour, reflecting the taxonomic closeness of these
trout species to the reference predator.
The proximate mechanism behind this response
pattern may be a difference in the suite of molecules that
form the trout odour. In this case, odour molecules among
the trout species are probably similar as they are
recognized by the minnows, but are not identical as the
minnows clearly differentiate the odours. Alternatively, the
graded responses could be explained by the existence of a
concentration gradient of specific chemicals. Fathead
minnows have been demonstrated to adjust the intensity
of their antipredator response according to the concen-
tration of predator odour they are exposed to (Ferrari et al.
2006).

UNQUOTE

So, some extrapolation is obviously useful. Other types of extrapolation and especially assumptions, are not. Because an insect can see in the UV spectrum can not be extrapolated to trout for instance. Indeed, it may not safely be extrapolated even to other insects.

Science is not there to "prove" things, but to discover how they work.

May also be of interest;

http://en.wikipedia.org/wiki/Scientific_theory

QUOTE
Assumptions to formulate a theory

This is a view shared by Isaac Asimov. In Understanding Physics, Asimov spoke of theories as "arguments" where one deduces a "scheme" or model. Arguments or theories always begin with some premises—"arbitrary elements" as Hawking calls them (see above)—which are here described as "assumptions". An assumption according to Asimov is...

...something accepted without proof, and it is incorrect to speak of an assumption as either true or false, since there is no way of proving it to be either (If there were, it would no longer be an assumption). It is better to consider assumptions as either useful or useless, depending on whether deductions made from them corresponded to reality. ... On the other hand, it seems obvious that assumptions are the weak points in any argument, as they have to be accepted on faith in a philosophy of science that prides itself on its rationalism. Since we must start somewhere, we must have assumptions, but at least let us have as few assumptions as possible.
UNQUOTE

http://www.arachnoid.com/theory/index.html

http://www.arachnoid.com/wrong/index.html

http://www.arachnoid.com/reader_exchang ... ience.html

TL
MC

[Mike Connor]

Of very special interest there is the story of "Darwin's Clock";

QUOTE

Darwin's Clock

This is one of my favorite stories about the power of theory to unify otherwise seemingly unrelated scientific fields. While doing preliminary research for what would become the Theory of Evolution, Charles Darwin proposed a mechanism for species evolution called natural selection. But a problem arose — natural selection required a certain amount of time and, based on the theorized age of the earth, there wasn't enough time for natural selection to produce observed species and their level of complexity.

In Darwin's time, assumptions about the age of the earth hinged on assumptions about the mechanism responsible for the sun's energy. In the mid-19th century, the sun was thought to radiate by the converted energy of gravitational contraction. Unfortunately for Darwin's work, this mechanism only allowed the earth to have a lifetime of millions of years, not the billions required for an evolution from single-celled organisms to modern vertebrates. Being a scientist, Darwin took this problem very seriously — he even went so far as to consider the idea of inheritance of acquired traits, which, had it been true, would have greatly sped up natural selection. But as things stood, given the assumed lifetime of the sun and barring an ad hoc explanation like inheritance of acquired traits, Darwin's theory stood falsified by an older, better-established theory with more observational evidence.

It was only in the 1930s that Hans Bethe provided a detailed explanation showing that the sun's energy arises from nuclear fusion, not gravitational contraction. Nuclear fusion directly converts mass to energy, a process that can go on for billions of years, and the last serious barrier to acceptance of natural selection was removed. This paved the way for the so-called Modern Synthesis, the present understanding of biological evolution.

In this way a theory in particle physics provided critical support to a theory in biology. It's hard to imagine two scientific fields with less in common, and this story dramatizes the unifying effect of scientific theory.

UNQUOTE

From; http://www.arachnoid.com/theory/index.html

TL
MC

[overmywaders]

Mike,

You said:

PS. In the quoted study, the perception involved is related to what the fish can sense in the water, and in this case is not visual, but might be loosely described as "scent", or "olfactory stimulus".

I had presented that study in the context of the "training" of trout

I don't wish to interfere with what I hope will be an animated discussion among members of the forum; however, as regards the trainability - not intelligence or educability - of trout, there has been some fascinating work in recent years.

It is not relevant in that regard which sensory inputs were used, simply that cerebral associations occurred. Your later remark is misdirected.

I had hoped that your statement:

So saying that trout have good vision but poor perception is a problem.

would have been picked up by someone and addressed by now. However, the dynamics of this forum, or maybe just that my presentation was too boring for the readers, seems to allow unsupported remarks like that to pass. Where in my initial post did I say that trout have "poor perception?" In fact, the article seemed to suggest that the trout's perception was appropriate to the needs of the trout. If a trout's perception, or any wild creature's perception of their environment, is "poor" that creature will not survive long, unless due to unusual circumstances.

Then you said:

Pattern matching in the form described has to be learned and is a higher brain function which trout do not possess.

as proven by the research done by.... " Where is your support for this statement?

As I am not working today, I will take a few minutes to address the matter of intelligent discourse among humans, as I understand it.
When people desire to search out the truth of matters, not simply to expound or pontificate, they proceed in the following manner:

1/ a person (P1) presents a premise and then sits back dispassionately, awaiting an honest response. P1 has done this in the hope that his fellows may be able to offer insights that will expand the knowledge of all. P1 has no emotional attachment to his premise, though it may be the result of years of study, he wants to investigate truth and desires the input of others; even if this disproves his work.

2/ P2 offers a response. This response will present a logical basis for either enhancing, agreeing with, or disputing P1's premise. If citations are available to support the reasoning, so much the better.

3/ Everyone thoughtfully considers the response. It is the message, not the messenger, that is relevant. The source of either the subject or its rebuttal is not of interest. Everyone feels free to contribute without fear of ridicule or censure.

4/ P3 and others discuss the original premise and any logical arguments to support or reject it, in whole and in part.

The above is just my understanding of polite and intelligent investigation of truth. Anyone who feels that I am wrong in this matter, please respond.

Regards,
Reed

P.S. - I would like to add that use of primary sources is important to any discussion. This allows everyone to examine the original basis for an assertion; not just hearsay or wikipedia.
P.S. - if the site admin feels that this thread has no bearing on fishing, or is not being presented in accord with the rules of the forum, please delete the entire thread. Thank you.

[Mike Connor]

If you could restrict your input to one thing at a time I would do my best to answer it if I can with whatever factual support I am aware of. I don't know everything about anything so I can't answer all questions anyway. I only usually comment on things that interest me or I think might be relevant.

If you want every post in the form of a highly formalised scientific study with quotations, studies, related matters etcetera, then quite apart from the time and effort involved, which I am not prepared to expend, this will result in massive posts which many people wont even bother to read and of course would then be useless to most. Not all these things are usefully related to fly-fishing, in the sense that knowing them will help people catch more fish. They are very interesting and I enjoy discussing things like this, but they are not relevant to what most people want.

Discussing these things "informally" as is done here and in most similar places is only to help people understand some things relevant to their fishing. This necessitates some simplification and abridgement. If you want to check on the accuracy of any particular statement, you can easily do so, and refute it if you discover that it is incorrect. I do not maintain that anything I say is the "absolute truth", regardless of how you may wish to define that. I don't mind at all if you disagree with something, and if you feel strongly about it, or consider it misleading, or simply wrong, then go ahead and refute it. I may answer it, I may not.

I am not trying to prove anything at all, merely trying to discover how some things may help my fishing, and part of that is finding out about things that wont.

Unfortunately, we seem to have entered into contention on some things, primarily as a result of my strong disagreement with your UV related ideas. This is unfortunate, but there is not much I can do about it, as I do strongly disagree, which is why I replied to you at all. I could just have ignored it.

I am not at all interested in "winning debating points", "proving I am right", or anything like that. I consider it a complete waste of time and effort. You can take what I have to say however you like, it makes no difference to me. If it is useful to somebody, then fine, if it isn't that's also fine.

I am not going to argue about things, this just inevitably results in people getting upset and the discussion turns into a squabble. I can not force you to do anything at all, and the same applies to you with regard to myself. I subscribe to this forum because of my interest in fly-fishing. If I wanted a full scale scientific debate on various things I would go elsewhere for it.

TL
MC

[overmywaders]

I think, Mike, that if you wished a real discussion to occur, then, when you say

So saying that trout have good vision but poor perception is a problem.

and someone replies

Where in my initial post did I say that trout have "poor perception?" In fact, the article seemed to suggest that the trout's perception was appropriate to the needs of the trout. If a trout's perception, or any wild creature's perception of their environment, is "poor" that creature will not survive long, unless due to unusual circumstances.

that you would address their response.

A gentleman might respond
"Sorry, I misunderstood what you wrote. I see now that you didn't refer to the trout's perception as poor."
or
"You misunderstand what I meant by poor, I meant..."

Instead, whenever someone rebuts one of your unsupported statements you do not respond to the counter-argument, you attempt to misdirect through ad hominem attacks or poor obfuscation.

Rather than have the admin lock this thread, I would ask him to remove all my posts, including the orginal post.

[Mike Connor]

I think, Mike, that if you wished a real discussion to occur, then, when you say

So saying that trout have good vision but poor perception is a problem.

and someone replies

Where in my initial post did I say that trout have "poor perception?" In fact, the article seemed to suggest that the trout's perception was appropriate to the needs of the trout. If a trout's perception, or any wild creature's perception of their environment, is "poor" that creature will not survive long, unless due to unusual circumstances.

that you would address their response.

A gentleman might respond
"Sorry, I misunderstood what you wrote. I see now that you didn't refer to the trout's perception as poor."
or
"You misunderstand what I meant by poor, I meant..."

Instead, whenever someone rebuts one of your unsupported statements you do not respond to the counter-argument, you attempt to misdirect through ad hominem attacks or poor obfuscation.

Rather than have the admin lock this thread, I would ask him to remove all my posts, including the orginal post.

What you think, is completely irrelevant to what I think, do, or write. Your opinion of my character or what you think I "should" do, or what a "Gentleman",( according to your definition), might do, is also irrelevant.

I have made no ad hominen attacks at all of any description. This is just more nonsense, and also ad hominem.

http://en.wikipedia.org/wiki/Ad_hominem

I have attempted to converse with you in a sensible civilised manner, but unfortunately you do not seem capable of it. I will not reply to you again.

TL
MC

[Otter]

Perception is a tenuous beast, as an example..

I arrived home about an hours ago, my wife said to the kids , " dads home from work" - now no one would be brave enough to say my wife was not perceptive but she was right that I was home , wrong that I was home from work.
Ya see, work was cancelled to-day - I cancelled it .... and went chasing trout.

The weather man is quite perceptive , but rarely right - the wind howled downstream at twice the forecasted rate.

I was however highly perceptive, I reckoned it would be a hard day and it was.... perceptive.....no no no, cold wind downstream in march = poor fishing = experience.

still I managed a few nice trout , my flies looked right, they grabbed, automatically i lifted ....voila , simple old game this

[Jim Slattery]

what's going on?