Tuesday, September 18, 2012

A Beast With Two Backs - Part II

(This entry is an addendum to my previous post, A Beast With Two Backs - The Gray Photo Deconstructed.  I would suggest reading the main article first if you haven't already.  I'll integrate the two posts into a permanent page on this site later.)

I thought I'd be done with the Gray Photo for awhile and get on with the larger topic of this blog, but the original article engendered so much comment on the buoyancy issue, the "balloonish" shape of the object in the photo, I knew I had to do one of two things.  I considered putting Nessie on a low-fat, vegan diet and waiting for her to slim down and answer her critics herself, but in the end it seemed more politically correct, perhaps even chivalrous, to post a short sequel and defend her bodily proportions myself.

It has been a long-time criticism of the Gray Photo that the object appears to float much too high above the waterline to be a natural object or real animal.  My previous post dealt with this issue in passing, but it clearly requires a greater explanation, and a broader one covering three things:  What We Have In The Photo, What's It Doing? and What Else Might Be Going On?


1. WHAT WE HAVE IN THE PHOTO

The first thing addressing this was implicitly the main point of the article: it's not one but two animals in the photo, most evident in the cleaner Heron-Allen print than in the press photos.  Thus the observed vertical height is not that of a single animal.  As we're looking downwards at two parallel bodies, the top of the further animal can be seen "above" the dorsal line of the front-most animal, accounting for about 25% of the overall vertical height perceived above the waterline.

Separating the image into two bodies, and clipping out the furthest of the two animals (see figures below) is not the only thing that reduces the vertical axis of the front animal relative to its horizontal axis.  We must also take into account the perspective from which the photograph was taken.  Had Hugh Gray lain on his belly at the shoreline to take the photo, then the picture would show only the profile of the animal, and the true ratio of the visible length to the visible height.  But Gray was standing on a high bluff, looking downwards at a point believed to be just south of where the river Foyers enters the Loch.  We must know the angle from which he took the picture in order to estimate the true horizontal perspective.

In the original article I had calculated an angle of 8 degrees based on the details of Gray's account as were published in various sources (not all of which completely agree with each other), as well as the observations of researches who had visited the site on the bluff.  Whereas Gray himself said he was about 30 feet above the water, the majority opinion tended towards that elevation being 40 feet.  F.W. Holiday claimed a height of 50 feet, and from the map in his book The Great Orm Of Loch Ness (W.W. Norton and Co., 1968, page 30) he was indeed talking about the same bluff widely, but not universally, accepted to be the correct spot.  I originally went with the 40 foot height estimate, which coupled with the 100 yards distance to the object Gray also reported gave us the elevation of only 8 degrees.

Now there is fresh data.  I am very grateful to Dick Raynor for not only contacting the experts with the Ordnance Survey, but also visiting the site in person and dropping a measuring tape from the bluff.  The present, confirmed height from the edge of the bluff to water level, with a meter added to allow for Gray holding his box camera at waist level, is 30.9 feet.  Remarkably close to Gray's original estimate, and less than the 40 feet I used in my original calculations.  I should add that Mr. Raynor himself suspects the Gray Photo was probably taken at a different, as yet unidentified location other than the commonly accepted spot on the bluff.  Dick has been studying Loch Ness since 1967, and I highly recommend a visit to his Loch Ness Investigation website for anyone with a serious interest in the subject.  But if you have grand illusions about the "wealth" of photographic "proof", especially in things like plesiosaurs, giant flippers, and gargoyle heads, be prepared for a refreshing shower of logic.

Dick was also helpful in suggesting a method for extracting the true angle at which the Gray Photo was taken from the picture itself, rather than relying on Gray's distance estimate.  This hinges on the concentric ripples emanating from the leftmost tip of the object, which I take to be the tail of the animal.  These waves would of course form circles if seen from overheard.  The degree to which they've been deformed into ellipses by the angle of view can be calculated by measuring and comparing the ratio of the major and minor axes of these ellipses.  This is a perfect and objective method in principle.  Putting it to practice, I ran into the difficulty that the larger ellipses, the ones most suitable for precise measurement, are truncated on the left by the end of the photo, and they are blocked on the right by the main body itself.  Tracing these partial ellipses and then completing them by eye introduces a subjective element I'd rather have left out, so I welcome any suggestions to further refine the method.  What I have settled for in this instance is the range of values I obtained from these tracings, with these falling between a minimum of 19 degrees and a maximum of 31.2 degrees elevation.  The lower value came from the smallest ripple, and is therefore more prone to error than the higher values obtained from the larger ones.  I'm confident Gray's true angle of elevation falls between these two numbers, but leave it for a real expert in photo analysis to pin the precise measurement down further.

Setting aside the overall significance of Gray's elevation being close to 30 degrees for a few moments, let's finish up with this whole buoyancy issue first.  Let's draw in a waterline as a reference point on the Heron-Allen image, and highlight the dorsal outline of the front-most of the two animals.  And let's for good measure excise the second animal from the photo altogether (images below).  Last of all, let's do something to take into account the fact we are looking downwards at the animal from an elevation of 30 degrees.  Unfortunately it's not a hologram, so we can't really rotate the body in 3 dimensional space.  But the problem isn't complicated enough to really require that for our purposes here.  Mathematically it's similar to rotating the ripples from ellipses into circles to determine the angle of elevation in the first place.  What happens when you correct the horizontal perspective for that 30 degrees of elevation?  Luckily Paint Shop Pro has a filter for that, and the result is the last of the three images below.

FRONT ANIMAL OUTLINED (click for larger image)
REAR ANIMAL REMOVED (click for larger image)
TILTED BACK 30 DEGREES to approximate profile viewed at water level

What we end with is a considerably flatter profile than what we started with when we had the backs of two side-by-side animals viewed from above.  (That we also end up with a profile that correlates astonishingly well with the body plan of a member of the family Cryptobranchidae is something I'll get to in just a few more paragraphs.)  The isolated side view of the nearer animal is, to say the least, far from "baloonish" anymore, and there is no longer reason to presuppose there is less of the total body below the waterline than above it!  This last image is still only an approximation of the horizontal profile, and contains distortions we can't correct without more work.  For example, the head still appears artificially raised above our reference line because it was turning to the left in the original photo, and the simple perspective filter I used cannot correct for that.  To get rid of that illusion and do a truly proper job of this, we'd have to hand draw contour reference lines onto the original body (to serve as the missing "3D" data) and then feed it all into proper CGI software.  I welcome anyone to give that an attempt and share the results here.  The point for now is that any further straightening of the neck and tail, and lowering the head to get everything in line with the long axis, isn't going to make the body thicker than it already appears, but will yield an even thinner profile than what we've already obtained here.

Now there's two more things that address this whole floatation issue, separate from the image in the photo itself, and fortunately they don't require trigonometry and diagrams, only logic:


2. WHAT'S IT DOING?

It, or more precisely they, there being two of them, are in motion.  Hugh Gray described the object to be in considerable motion, with much splashing and noticeable thrashing of the tail(s).  But he never spoke of forward progress or swimming, nor of horizontal movement.  His report tells us the object surfaced, made a considerable commotion in one spot for a few minutes, and then submerged presumably in the same spot it came up.  This is totally consistent with the photo itself, which shows no wake.  So if this considerable motion is not horizontal, it has to be vertical.  For whatever reason these animals bobbed up to the surface where they did, bobbing in one spot is what they were doing.

That means from moment to moment, varying degrees of the bodies were vertically exposed.  There's no need to justify how the animals held themselves up at whatever highest point they obtained, because it was a transitory oscillation in the vertical movement, not a pose held for the count of ten while the photographer said "cheese".  We have no idea what the mean value of the vertically exposed portion was over time, because we have only one frame.  A still photo can capture a very transitory event.  A snapshot of a whale breaching doesn't require a belief that whales can fly - and that's a good thing because there are plenty of genuine photos of whales completely in the air.  We do not say whales are too buoyant to exist, because we have snapshots of them fully clear of the water.  In my third illustration above, there's no reason to presume we have more than 50% of the animal visible above water at all.  So what's good for the whale is even better for the giant salamander.


3. WHAT ELSE MIGHT BE GOING ON?

By a wayward path, we now come back to the overall theme of this blog, the Loch Ness Giant Salamander.  The question has been raised as to how a purely aquatic, benthic animal could spend time above the surface at Loch Ness at all.  When an animal swims on the surface, it meets for more resistance than when swimming below the surface.  The laws of hydrodynamics dictate 60% more energy has to be spent by an animal swimming above the surface, and animals as a rule do not waste excessive amounts of their hard-won calories, at least not the ones that succeed evolutionarily.

But in the case of the Gray photo, it does not appear to be a case of surface swimming at all, it's a case of floating in place and thrashing.  Whatever this behavior represents, we do not have to explain it in terms of locomotion.  Still, the specific gravity of an aquatic animal designed for bottom dwelling would normally require it to burn energy paddling in some way to stay afloat on the surface.  Except, however, in one very important case: when the animal has lungs.  Once at the surface, inflation of the lungs becomes possible, this lowers the specific gravity of the animal, and floating becomes "cheap" if not completely free.  That doesn't aid forward locomotion one bit, but again we don't have forward locomotion to explain in Hugh Gray's photo.

During the course of their evolution, most of the terrestrial amphibians that re-adapted to fully aquatic living have, with few exceptions, retained their lungs.  The purely aquatic caecilians, which normally absorb all their oxygen through their skin, retain their lungs throughout life and come up for a breath when they aren't getting enough oxygen by their normal means (but see the recently rediscovered Atretochoana eiselti for a marked exception).  All species of aquatic salamanders have and rely on their little-used lungs when their ponds are low.  Axolotls also kept their lungs, despite having both gills and epidermal respiration, and when forced to use their lungs to survive during dry conditions will sometimes even morph into terrestrial salamanders.  And the largest recognized amphibian of all, the Chinese Giant Salamander Andrias davidianus, has retained its lungs and still uses them when needed, although it is fully aquatic and normally doesn't leave the water.  For as seldom as they use them, it's a fact all the living members of the family Cryptobranchidae have retained lungs, so a Loch Ness Giant Salamander falling in the same family would be quite likely to have retained them as well.  For as young as the Loch is geologically, a population of giant salamanders that arrived even shortly after the glacial melt would not have had enough time yet to lose its lungs through evolution.

If as I believe we have giant salamanders in the Gray Photo, then their buoyancy (if it needed any enhancing to explain the photo) would only require use of their lungs.  In fact the animals were apparently being so aerobically active with their splashing, thrashing and tail wiggling, it's possible the need for extra oxygen via their lungs is what brought this behavior up to the surface in the first place.  It's where all aquatic amphibians go when they are running out of breath, at least if they want to sustain the activity that was costing them the extra oxygen to begin with.

Between these three things, the corrected profile of the front animal in the photo, the vertical bobbing that had to be part of their motion on the surface, and finally the presumed ability to inflate their lungs once on the surface, I see no room at all to refute the authenticity of the Gray Photo based on flotation or any issues dealing with buoyancy.


AND LASTLY

As promised I must return to an issue raised earlier.  That the true elevation of Hugh Gray's camera at the moment the picture was taken is actually close to 30 degrees (at least 19, but probably closer to 30) raises its own questions.

Gray's estimate that the object he photographed was 100 yards (300 feet) away is clearly impossible if his elevation was 30.9 feet, and the angle derived from the rippled wave measurements in the photograph is as much as 30 degrees above horizontal.  One need only dust off the Pythagorean Theorem to work that out.

If the location of the bluff is correct, and the height of the water is correct, and the 30 degree angle is correct, then the object can only be 60 feet from the camera (and that's generously using the hypotenuse, although that is technically the line-of-sight portion of the triangle).  And 60 feet is hardly comparable to 100 yards.  This picture was taken from considerably closer than the distance for which Hugh Gray was quoted.

If the picture was taken from another location at a higher elevation of say 50 feet (that was the number Ted Holiday gave), then line-of-sight distance to the object comes in at nearly an even 100 feet, but still not 100 yards.  Could Gray have misjudged the horizontal distance by a factor of 3?  Were his units of measure misquoted in the accounts?  Proposing two exceptions as an explanation begins to feel like stretching the truth to fit the data, which is rarely a safe idea.

Now is probably a good time to remember the angle of elevation I derived from the elliptical wave patterns was fuzzy, between a low of 19 degrees and a high of 31.2.  That will have to get pinned down at some point.  At that lower estimate of 19 degrees, the line-of-sight distance to Gray's object becomes 95 feet (from an elevation of 30.9 feet) or just over 150 feet (if the picture was taken from a hypothetical spot 50 feet up).  But this last possibility is stretching things; not impossible, but decidedly less probable.

In any of these number games, we end up with a photo taken from a much closer spot than traditionally believed.  Which at least serves one helpful purpose:  this accounts for the absence of the far shoreline from the top of the picture, without having to depend on creative cropping or theoretical tampering for explanations.  At Foyer's Bay the opposite shore is relatively close, and a photo taken straight across the Loch from an angle as low as 8 degrees or less would almost certainly have had to include that opposite shoreline in the picture, just over the animals' backs.  That Gray was aiming downwards, at a steeper angle and at a closer point, solves this part of the problem.

As one can see, there is still more work that needs to be done with the Gray Photo, but as that's not the sole purpose of this blog we shall let that rest for awhile.

13 comments:

  1. Hello,

    Could the activity be due to breeding? Interesting article, thanks.

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  2. I wouldn't be at all surprised if it was. Various species of salamanders display a wide variety of courtship practices, some of which include side rubbing, tail wriggling, and throwing water sprays at each other using their limbs. Such a mating dance is entirely consistent with what we have with the two animals in the Gray Photo.

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  3. Do we know the name and or model of the camera that Mr Hugh Gray used?

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    1. The camera type and lens don't seem to be specified in the accounts. And I know little of cameras myself. A standard box camera for the period seems a likely assumption. If that is the case, Dick Raynor has suggested to me that then it was likely a 90mm miniscus lens, 120 film, with a field of view of either 33x33 degrees, or 33x50 (with the latter model being the more likely). Unpublished composites I've done still don't add up to a completely uncropped image, but do come close to approximating a 33x50 field of view.

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  4. Fascinating stuff.... all your analysis of the Gray photo sounds perfectly plausible, as does Roland's on the loch ness mystery bog, but I have a question. Are there other sightings similar to this one, with "thrashing" going on at the surface, and how common are they. If this was indeed typical behaviour of the animal in Loch Ness, shouldn't we expect sightings like this more often?

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    1. Thanks Andy. At a glance I'd estimate the terms "commotion", "disturbance", and "splashing" come up in roughly 20% of sighting reports. Even the lovely term "gamboling" on occasion. All too often these observations aren't more specific, and probably refer to more than one type of behavior. Now there also have been plenty of reports where observers were sure they were seeing two separate animals, and a number of sonar contacts implying the animals typically travel in pairs. But two animals floating on the surface rubbing sides and deliberately tossing water onto each other seems far from a common observance. That could well be because it normally happens more at night when it would be impossible to observe, or it may actually have been going on where witnesses only reported a "great commotion" at some distance too far away to tell that's what was going on. Something I find so intriguing about the behavior captured in the Gray Photo is that it *is* a typical form of courtship behavior among many species of salamanders. If Hugh Gray hadn't had a camera and snapped that picture, his sighting report would sound very typical of many others: just a lot of commotion with no idea it was caused by two animals that close together.

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  5. Thanks for the reply....when can we expect the 3rd part of your "New Morphology" articles?

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    1. Sometime in April - have a bit of distracting family business going on, so hard to be sure. It should be shorter than Part 2, which covered such a broad swath. It's focus will be on what we may deduce about morphology from land sightings, which should prove interesting.

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  6. I'll look forward to it...

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  7. If these are the loch ness monsters then how come they are not dark like 95 per cent of sightings say?

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    1. The areas just doused and being doused with spray are highly reflective, whereas the dryer areas do indeed appear dark -- at least darker than the water, but understandably not as dark as the shadows the animals are casting on the water.

      Dinsdale grappled with the conflicting reports of the animals' integument sometimes appearing glossy and highly reflective, even slimy, while other times looking like elephant hide. I believe he was correct in deducing that smooth skin would always look smooth, whereas rough-textured skin could look like either depending on how wet it was and the angle of the light. Thus he concluded the animals do indeed have a rough textured skin, as that accounts for both types of sightings.

      And the light and dark areas of the creatures in the Gray photo, apparently flipping water at each other, are an excellent example of exactly that.

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  8. Hi. The head of the object looks the spit of the head of a large eel with its mouth open.

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    1. Indeed, I agree! And Roland Watson has observed the same. And yet we have a mid-body thicker than any known eel, apparently four appendages, and a good hint of a caudal fin on the tail region. Amphibians can have some very fish-like features, but eels don't have this array of tetrapod features, leading me to say and think "salamander" rather than eel, despite the head's profile.

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