Friday, May 09, 2008

What is it like to be a fish?

What is it like to be a fish?
Andre Willers
8 May 2008

For Egbert Louw Jr

What is it like to be bat?
There is a famous philosophical treatise by the philosopher Thomas Nagel titled : “What it is like to be a bat” . Google it for the article .

In the finest polysyllabic , philosophical tail-chasing style he states that experiencing a truly alien consciousness is impossible , but he also makes the statement that we can sneak up on it . This is what he is famous for .

The relevant quote :

“This should be regarded as a challenge to form new concepts and devise a new method—an objective phenomenology not dependent on empathy or the imagination. Though presumably it would not capture everything, its goal would be to describe, at least in part, the subjective character of experiences in a form comprehensible to beings incapable of having those experiences. “

To be able to do that , we have to have a mapping method relating the bat’s sensorium to the human visual system . This is the other reason why he is famous . The bat is sufficiently alien , yet still a mammal . The underlying neurological structures are still mammalian . We can still make a map .

A number of mammals have successfully adapted visual information processing brain-systems to handle echo-location . Dolphins , whales and bats are but the best known ones . This is no accident . There is a deep underlying neurological structure that makes the conversion between binocular vision and echo-location depth perception possible .

We can thus know that we can map the sensorium of a bat to an analogue of our visual system .
Evolution has already done it .

A pulse of sound composed of rapidly varying frequencies . By analysing the time-returns and absorption characteristics of the reflected chirp , information analogous to shape and colour can be inferred . Also used in human chirp-radars .

So , how does a bat see?
Like a myopic human with 95% vision , but with a Vector-sense of motion of objects inside the chirp cone .

He flies through a 30 metre visual bubble in which he can clearly see things and motion-curves of objects bigger than about 0.5 mm . Outside it , things are misty .

We know that they can discriminate half a mosquito length from about 10 metres . This is nearly as good as human vision . But objects in relative motion are highlighted in the chirp-cone .

This is the motion sense , which humans do not have : the alien bit . Like a vector arrow on a radar-screen . Humans have to calculate the vector of motion , bats perceive it directly . Since the refresh rate is directly proportional to the chirp-cone scanning rate , the bat perceives curved motion directly in his sensorium .

This is why they can catch insects on the fly .

The chirp-cone is flicked around in scanning cone , much like the saccades in the human eye-ball . Doubtlessly , there are some very sophisticated optimization scanning algorithms involved . The bat sees a seamless picture , like a human sees a seamless picture in his sensorium . All the low-level jittering is smoothed out in the sensorium .

The alert reader will have noticed that bats have a better sense of time-binding than humans or monkeys . They can perceive trajectories directly .

Why are bats not then the dominant life-form on the planet ?
The same evolutionary trap that got birds : the atmosphere is not thick enough to sustain a flight-form with sufficient mass to have a large individual brain . If they come to land , they have to compete against superbly adapted land-predators . I have seen some videos of bats on foot actually running down small prey . But any decent cat or dog family member would soon put a stop to this .

There have been some speculations (Vernor Vinge is notable) of sound-linked communal minds . I see no inherent theoretical impossibility . But the brain has to be large enough to handle the essential data-linkages . This would require packing-protocols outside evolutionary boundaries . But , I suppose , some demented scientist could create intelligent bat-communal beings . They would out-compete any other mammals .

Bats are likely to survive an eco-catastrophe . (Time-binding goes deep . ) If surface dwelling niches are opened to them , they could very well evolve to smarter and better caretakers of the planet than humans .

What would it be like to be such a bat ?
Since they can directly perceive a trajectory , self-destructive behaviour would be much less likely .

“Catch the mosquito while diving into the ground” would be one of their favourite sayings .

More intelligent than humans in calculating consequences , but less creative .
Pak-protectors without the xenophobia .

Now we sneak up on the fishes .

First , look at dolphins , whales , etc . Their sensorium is similar to that of the bat . Their primary sense is the echo-location chirp . But water is different . A dolphin sees a three-dimensional sensorium of another water-animal . At first glance , the sensorium should be overwhelmed by too much information . There is no surface to a sonar scan of a water-filled animal. This is why the chirp is important .

Time and absorption differences to the various different frequencies in the chirp enables the dolphins sensorium to construct the “surface” of whatever is scanned .

It was thought that the dolphin saw a human in the water like we would see a glass model , with all the organs somehow magically delineated . The dolphin simply does not have the processing power to see three-dimensionally . What it does is use the tried and trusted surface-visual algorithms to do layering . It can see various sound-reflective layers . As far as a dolphin is concerned , a human is not a single entity , but a compendium of layers . But all the other living things in it’s environment is like this

It can focus on various aspects .

The critical question is : what is the definition ? What is the smallest thing a dolphin can sense with its chirp ?

The evidence suggests about half a cm . There is a heavy energy cost to generate really high-frequency water pressure waves .It is not like sound waves . The minimum necessary would evolve . The sensorium of a dolphin would have significantly less definition than that of a bat . (Factor of 10)

Dolphin Sound Spectacles .
Since humans are so enamoured of dolphins , why not give them glasses?
Not for their eyes , for their sonar .
Uplift them .

Noise-nullification technology can be easily adapted to give a dolphin the resolution to see things at cellular level . Even a classical large lens of denser than water material will do the trick . The inverse can just as easily be done , to give them the capability of zapping tumours .

They are already rumoured to be beneficial to sick humans .
I would not be so sure about killer whales .

Or zygote manipulation .

I draw your attention to the unpredictable effects of giving spectacles to human populations .

The reason why dolphins et al do not communicate is that they cannot see us . They need glasses to focus .

Do humans have the courage to do this ?

Now for what it is like to be a fish .
Fish are not mammalian . Rather trite , but true . The primary sense organ of the fish is the pressure sense . A fish uses pressure to sense how far away it is from the surface of the water .

Near the shore:
So , to think like a fish , invert . Your upside down feet is treading on the surface of the water from the bottom . If the surface is choppy , think of walking over rough ground .

It costs the fish energy and effort to maintain an equal depth .

Where would you go ?

Where feeding and turbulence combines optimally . Two thirds away from the centre of a sloop and two thirds down at that point . (Values derived from Infinite Probe considerations)

If you think walking upside-down under the sea-surface is weird , you should try me on my better days .

Bottom dwellers cling to the sky .

Scent and electrical senses also play a role .

The fish “sees” an endlessly quaking surface under it , with the mists around it riven by channels of scent , with a false top of the thermocline .

Sharks examine things close by via electrical fields . So they see the close environment as twisting network of electrical fields .

A lemon with connected copper and zinc wire should make a fine shark lure .

What is it like to be a deep sea fish ?

Untrammelled freedom .

The densities of population in the deep sea used to be lower than survival levels . Continental shelves were used for risky spawning . That is until humans conveniently started melting the ice-caps , causing upwellings of nutrient rich waters along the oceanic trenches . You don’t need shoals to ensure reproduction . Think like a fish , with about 400 million years of survival mechanisms .


Tortoises and their like navigate by treading the sky .

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