The evolution of the human eye - Joshua Harvey

The human eye is an amazing mechanism, able to detect anywhere from a few photons to a few quadrillion, or switch focus from the screen in front of you to the distant horizon in a third of a second. How did these complex structures evolve? Joshua Harvey details the 500 million year story of the human eye.

Lesson by Joshua Harvey, animation by Artrake Studio.

[finntran]

When I take my glasses off it feels like I went from 4K down to 144p buffering 😂😂😂

[Starlight]

My new favorite hobby is drinking tea and looking at athiests and theists argue in the comments section of evolution videos

[mengo]

If i could design an eye i would make one without astigmatism.

[GraemeMarkNI]

This is great. There's one small thing. It was recently discovered that some supporting cells in the retina called Muller glial cells act as fibre optic cables and focus the light onto each individual photoreceptor. So although it appears like the retina is in backwards, it may actually work MORE efficiently the way it is. Your point stands for the blind spot though...

[PetarStamenkovic]

A tough topic to cover in such a limited time. I think you've done very good job TED-ED team.

[pratyushdam]

charles darwin stated that it seems highly absurd that eye could have evolved, however he continued the sentence stating how it could have evolved.
please dont spread misinformation.

[VolantisAcedia]

To be fair, I've heard that Charles Darwin gave an explanation for the evolution of the eye, he just introduced it by saying that often misunderstood line.

[legendarypussydestroyer]

2:58 "far from being an *eyedeal* masterpiece..."

[sagarbodhe]

I'm so glad to be alive. TedEd makes me realize how beautiful it is to be alive. Thank you.

[cwcorella]

Here is Darwin's quote in FULL context, it clearly demonstrates his thoughts on the matter to be quite the opposite.

"To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, _seems_, I freely confess, *absurd in the highest degree*. When it was first said that the sun stood still and the world turned round, the common sense of mankind declared the doctrine falsebut the old saying of Vox populi, vox Dei, as every philosopher knows, cannot be trusted in science. Reason tells me, that if numerous gradations from a simple and imperfect eye to one complex and perfect can be shown to exist, each grade being useful to its possessor, as is certainly the case; if further, the eye ever varies and the variations be inherited, as is likewise certainly the case; and if such variations should be useful to any animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, should not be considered as subversive of the theory. How a nerve comes to be sensitive to light, hardly concerns us more than how life itself originated; but I may remark that, as some of the lowest organisms, in which nerves cannot be detected, are capable of perceiving light, it does not seem impossible that certain sensitive elements in their sarcode should become aggregated and developed into nerves, endowed with this special sensibility."

[PickyMcCritical]

2:00 Transparent humor? I don't see how that's funny.

[vnm_midnightios]

I bet nearly everyone looked off to somewhere else when he said "it can change from this scene to the distant horizon in less than 1/3 of a second"

[samuelvancik]

My humor at a drunk party is the same as the one that fills out our eyes.

[tundrawolf]

why am I binge watching these videos?...

[notpickybutstrict]

if I want to change my eye, I would want 5 x more rods and 32 different color receptor types.

[Dyslexic-Artist-Theory-on-Time]

The human eye is an amazing mechanism, able to detect anywhere from a few photons to a few quadrillion, or switch focus from the screen in front of you to the distant horizon in a third of a second. How did these complex structures evolve? Joshua Harvey details the 500 million year story of the human eye.

[hallowacko]

Just FYI, in the very next sentence, Darwin stated that, even though it seems improbable, he could imagine successive forms evolving even into this super complex structure.

[Snyphen]

It's not a question of maybe. Artificial eyes will one day surpass our natural ones. You could say that for any part of the body, including the brain.

[switchyduckk]

Tryna fall asleep but I can't stop thinking of these *eye opening* concepts

[jacquelinebrannon]

I know this isn't related, but I really like this narrator. His voice sounds really nice and makes me pay attention more