Natural selection is about the survival of the fittest, but it is not perfect. How can we fix it?
Episode 1
"The Eye Of The Beholder"
(See minute by minute synopsis at the end of the presentation)
Episode 1, Development
Section 1
Sight is the ability of detecting light and processing the abundance of information that light brings with it, information that helps the living organism survive.
Sight enables the animal to see pray or predators from afar, distinguish friend from foe, identify mates and what they offer, and so much more.
Therefore, sight is a precious advantage that is positively selected for by nature. Indeed, during animal evolution, sight has evolved several times over in an independent manner.
The first step towards the ability to see anything is to convert light (which is made up by photons), into electrical signals (which is known in science as “membrane voltage”).
The process of translating light into electrical signals is known as “photo-transduction”, and is carried out by specialized cells in our retinas called photoreceptors (PRs).
The focus of this section is on emphasizing the importance of photo-transduction as the first step in seeing, and explaining the process in detail, using animation and “microscopy-imaging” methods.
Prof Edward Pugh and Prof Marie Burns, from the University of California at Davis, (CA, USA) are featured on the topic of the photo-transduction.
This process of photo-transduction is only the first step in sight.
What happens next?
The retinas handle the photo-transduction itself as well as many other initial steps in processing the electrical signals that will eventually reach the brain. In other words, after light is converted into raw electrical signals discharging across the retina, there is a need to process these complex signals and refine them.
Very similar to computers, our retinas perform calculations and resolve problems.
For example, our retinas can refine these electrical signals in order to resolve their color, contrast, resolution, depth, movement, shape and other aspects of the information contained in the original image, before this information is sent to the brain.
The brain gets “pre-processed” information, so it’s easier and faster for it to create an image in our consciousness.
While for very primitive animal life forms, knowing the difference between day and night might be enough, more complex animal behavior requires to know much more about the world.
Birds and mammals have complex retinas, that can effectively fulfill this purpose of “refining information”, thanks to an evolutionary process that added new layers of cells to the original structure of the more primitive retina.
This is why the human retina is upside down, because these new layers (“new” in evolutionary terms of millions of years), have been added on top of a more primitive, more basic structure.
This is probably the greatest example of how Evolution is a non-deterministic process, where fate is not set, and mistakes can be made. It’s a continuous struggle to fit into the environment.
If organisms were perfectly designed and created, the retina wouldn’t have its layers upside-down.
In this part of the episode, the human retina is showcased, emphasizing how other cells evolved on top of the photo-receptors.
Animation, microscopy images and animal/human footage are used in order to show, compare and explain the structure of the retina in different animals.
Prof. Helga Kolb from the School of Medicine, University of Utah, is an expert on the human retina and how it compares to other animals (mammalians, birds, insects, fish, amphibians).
She shares with us the reason that evolution resulted in this upside-down ‘mistaken’ design.
Episode 1, Development
Section 2
In this part we expand our focus to the whole human eye, far beyond the retina.
Other organs and parts of the human eye are also crucial for a sharp vision.
For example, our pupils can regulate how much light comes into the eye, to protect the retina from light so intense that it could kill the photo- receptor cells.
The lens in our eye serves to focus the light onto specific parts of the retina, and if it fails to do so our vision becomes blurry, and we have to wear artificial lenses that compensate for our own faulty ones.
The muscles in our eyes can trigger tightly-controlled tiny movements that help us re-focus almost instantaneously, whenever we switch from one image to the next.
In summary, the whole eye, from eyelashes to cellular layers in the retina, is an amazing piece of natural engineering.
Therefore, our next question is: how does it compare to artificial (or man-made) engineering?
We will answer this in the following three subtopics that are all related to the main topic: optics, light-waves and photo-transduction.
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Optics:
We deal with optics and optical devices, show how they work and, most importantly, how they compare to the human eye.
In the eye, a biological lens focuses light on a specialized portion of the retina, namely, the fovea.
Artificial lenses, microscopes, and telescopes are presented and the engineers are presenting and demonstrating their designs and constructions -
Light-waves:
The human eye is incapable of detecting certain light waves (i.e. ultra-violet, infra-red) but other animals, as well as engineered optical devices, can do it. The principles behind “wide-spectrum detection” are simplified and demonstrated. -
Phototransduction:
Photo-receptor cells in the retina convert light to electricity, but they have limitations.
Modern technology and engineering have far higher “photo-conversion” capabilities, which are used by us daily, from simple devices to high-power solar panels.
For the above three topics, footage and interviews will be obtained from the followings: The headquarters of the Olympus Corporation (microscopy giant corporation) in Tokyo, Japan; The biggest optical telescope on the planet, the GTC (Gran Telescopio Canarias) in the Canary Islands, Spain;
The Bell Laboratories (New Jersey, USA) where John Shive invented in 1948 the first “photo-transistor”.
When visiting the GTC telescope we show how, as opposed to human eyes, telescopes can see infrared light, and what information about the nature of the universe is uncovered using this capability.
Footage will also showcase the biggest solar panel array in the world currently under construction in the Moroccan part of the Sahara Desert, The importance of solar power for the future sustainability of modern human life is made clear.
Episode 1, Development
Section 3
Here we introduce the concept of blindness, as a result of the death of photo-receptor cells in the retina. We present the prevalence of blindness in society and the cultural aspects of blindness
through the ages, from the biblical patriarch Isaac and Tiresias in Homer's Iliad, to modern times (illustrated with animation/images/art).
Next, cutting-edge research into vision restoration (a cure for blindness) is showcased as we visit the lab of Prof. Richard Kramer at the University of California at Berkeley (CA, USA), and the headquarters of Second Sight, a company developing retinal prosthetic devices (Sylmar, CA, USA)
With narration and state-of-the-art animation, we walk through the methods that portray how stem-cells can be the future of curing blindness, by regenerating the photo- receptor cells that have been lost.
Scientists that try different approaches to solve the same problem are presented and we contemplate the strength of the evidence.
Episode 1, Development
Section 4
Futuristic ideas are presented.
For example, humans that are genetically engineered to never suffer blindness, and furthermore, to be able to see in infra-red and ultra-violet light.
Wearable devices and cybernetic components that will allow our sight to go far beyond what nature "intended" are presented.
How will future humans see their world?
Will this signify the beginning of a new understanding of reality?
This section features a talk with Nick Bostrom from the University Of oxford, UK.