Umboi: Did Rays Evolve The Ability To Fly?

Post 65, possibly.

 

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If so, then I was replying to phlog only. I tend to think in abstract and generic terms, whereas phlog seems to be obsessed with the idea of long slender wings being responsible for this sustained gliding. I was pointing out the obvious; that it is the lift to weight coefficient which is of primary importance. A delta wing, or ray shape, is perfectly ideal for this kind of aerodynamics and can produce just as much lift as the long slender wings of a bird's body plan. The weight of a ray is disputable, but I'm arguing that this could slowly be reduced via evolution and lengthen the time of a sustained glide.

 

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You think in abstract and irrelevant terms and pay no heed to rationality or common sense or evidence or logic. You just bounce from idea to idea, each time proclaiming you're irrefutable or its obviously right, you just need someone to fill in the details or provide evidence. On the rare occasion you stick to a claim long enough for anyone to be bothered you are disproven but you pay no attention and simply make another vast generic and utterly vapid claim.

In science imagination untempered by knowledge or logic is worthless.

 

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In post 65 you stated
"The weight aspect is often a red-herring that novices can't see past."

In post 73 AN responds:
"You mention how we might be making 'novice mistakes'. Why don't you explain, in detail using your knowledge of aerodynamics, precisely the mistake we're making. Please be as detailed and indepth as possible in your use of aerodynamics."

In post 84 AN observed:
"I'm still waiting for you to explain how we're being naive about aerodynamics."

In post 86 I stated.
"I'm still waiting for you to explain how we're being naive about aerodynamics. Your last response does not address the question."

In post 87 your non-response was
"I was refering to Phlog with that statement I seem to remember.
So do you except that rays could have evolved to fly in theory?"

In post 89 I responded
"It doesn't matter who you were referring to, at least two of us, AN and myself, would like to know the answer to AN's question. How are we being naive about aerodynamics?"

In post 92, displaying all the signs of advanced brainn damage you remarked
"I really don't know what you're talking about anymore."

To the foregoing inane, dismissive reply I posted this:
"Then fucking well pay attention. You made a claim in an earlier post that some of the posters in this thread were naive about aerodynamics. We wish to know in what way were they naive about aerodynamics.

It is really simple. you made a claim. we want you to provide the details of that claim.

Do you understand it yet? Just answer this question:

"In what way were posters in this thread naive about aerodynamics?" "

I followed this up with a series of repaeats of the basic question as you contiued to ignore it. Latterly, it seems, you responded to my insulting and offensive pm.

 

There you go with the word 'obsessed' again. Sense is not obsession. Science is not obsession. Long slender wings provide more lift, period. In aircraft we have moved to swept, or delta shapes, because long straight slender wings inhibit agility and limit top speed. Advances in propulsion technology allow us to apply more thrust, and make swept or delta shaped wings work.

I gave you the numbers. A 6metre Albatross would weigh in at less than 100kg. A 6 metre ray THREE TONNES. That co-efficient of yours is looking rather strained.

No. Simply No. Long slender wings are seen in soaring birds, because evolution has found them to be most efficient. They are seen on gliders, because aeronautics finds them most efficient. They were seen on the U2 for the same reason. Now we have composite materials and can make lighter aircraft, with better propulsion, we can make delta wing shaped stealth aircraft which can operate at longer ranges, BUT that does nlt alter the fundamental truth that long slender wings are more efficient for gliding, it just means we have ways of circumventing some restrictions.

No. Simply NO. Rays have to have similar density to the water around them. Their weight therefore is a simple scale against their volume, which is a scale against their wingspan. This HAS been explained to you.

No. Simply, NO. I already told you that flight evolved as a consequence of rapid growth in dinosaurs. Rapid growth needs bones to grow quickly, which meant porous bones, which meant lighter bones, which made flight possible.

You are getting it backwards. Flight was a consequence, not a goal.

 

As I stated before:

Insults and hysteria can't take this simple logic away I'm afraid. Does anyone have a valid argument why a small ray couldn't evolve to become lighter, so as to increase it's glide range?

 

Do you have a ruddy answer to the ruddy question?

 

Let's ask Enmos whether I've tried to explain myself. I believe I have.

 

Why me?

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You sure tried, but then you failed miserably.

 

You most certainly have not. AN asked this of you:

Why don't you explain, in detail using your knowledge of aerodynamics, precisely the mistake we're making. Please be as detailed and indepth as possible in your use of aerodynamics.

You have patently failed to do anything even remotely approaching this. All we have had from you is hand waving and claims that you think in general terms. General terms won't cut it here sonny. You have claimed one or more members here to be naive in their understanding of aerodynamics. Until you can demonstrate this clearly, or admit that you were wrong, I shall continue to hound you. So, please, cut to the chase, let's get this point dealt with now.

 

The mistake you're currently making is that I was refering to you in the first place. As I've already stated, it was Phlog who I had the problem with, not you or AN. My explanation was given in post#122.

The heavier than water argument IS NOT valid imo. This is because a heavy ray will still have some glide characteristics due to it's lifting body. The distance it travels may be very small, but it won't fall vertically if there is a strong upwind. There is also a valid mechanism for the evolution of a gliding ray to become lighter over the millenia (the parasite removal linked with predator avoidance).

btw I've flagged up the issue with the moderator.

 

Getting back to the thread, here's a reply from someone in another forum whom lends some support:

 

Jesus fucking christ, how many times? DENSITY.

A ray, to remain a ray, has to have similar density to water, so it can move about the ocean, and not have a predisposition to floating or sinking.

That said, it's WEIGHT, is dependant on it's VOLUME, which is dependant on it's WINGSPAN. The only way a ray can become lighter, therfore, is to become smaller. You need a ray with a wingspan on 6 metres. That weighs in at THREE TONNES.

IF you are proposing a lighter wing structure for a longer glide, that is the FLYING FISH which has a wing shaped like that of a BIRD, not a the fins of a ray.

You are not thinking this through. If the ray becomes less dense, it expends more energy to swim and sink, while saving energy flying. It would be rubbish at flying, and have a hard time swimming. Basically, your required evolutionary step is useless at both things. How would it survive?

 

Just to re-iterate: I don't read posts that start with swearing or insults in general. If you want me to take notice of what you have to say, then please do so in a considered and even toned manner. Thank you.

 

He is still allowed to ask you to justify your statements, and you have failed to do so.

Who said 'heavier than water'? Nobody, we said the ray is about the SAME density as water FFS.

Some? A great big floppy three tonne ray? To Glide, any lift generated by a wing must be transmitted through a fairly stiff member so it can act on the centre of mass of the object. You haven't demonstrated a ray can support it's own weight on it's fins, without that, they would just get pushed up and flap around due to any lift, although we all know that 'lift' is negligible compared to it's bodyweight. When you see rays breach the water, that's a ballistic trajectory, it's not flight.

I don't think a three tonnes ray is going is going to get blown around or lifted by the wind much, even with a 6 metre wingspan! Let's look at some practical demonstrations of this shall we? A friend of mine is into Kitesurfing. He has many and various Kites, with SURFACE AREAS up to 14 square metres. He weighs about 80kilos I guess. a 14 sq m Kite can loft him, and give him some air time. If however, the Kite was floppy, and he weighed three tonnes, he wouldn't be going anywhere. Hell, if his kite could move three tonnes he'd strap it to his car and save on petrol.

No there isn't. a lighter ray would be rubbish at flying, and become a surface dweller, uncapable of diving. It would be easy picking for a sea borne predator, and it would still not be capable of flight.

Which issue, the issue that you are an idiot?

 

Just fucking read it. No lame excuses for your bullshit.

 

'just the same' won't cut it. You need THIRTY TIMES MORE LIFT for the equivalent wingspan.

You cannot invent a 'lighter' ray because they would be incapable of swimming. (note, here, Penguins can swim, but they can no longer fly, ... do you see something in that, ... )

 

Or end with insults. (Or insults in the middle etc..yawn)

 

Excuses excuses.

You won't admit reading them because they shoot your flying ray out of the water.

You are just copping out because you have nothing, no fact, no reasoning, no science.

 

So the person who posted this view is also an idiot in your opinion?