Island Tribes Develop Superior Underwater Vision

Artifice_Eternity writes "I found this Washington Post article fascinating. A tribe of skilled divers known as "sea gypsies" have developed a previously unknown physiological adaptation that gives them better vision underwater. Most humans see poorly underwater, because water has a similar refractive index to the fluid inside the eye, making it difficult to focus incoming light. But children of the Moken tribe compensate by shrinking their pupils (the same way photographers reduce a camera's aperture size to increase sharpness). Their underwater visual acuity is more than double that previously thought possible in humans. The article also describes other adaptations discovered in recent years that challenge our understanding of what the human body and brain can do." (Painless non-registration demographic click-through required.)

Comments

Learned?

[crisco]

I found it interesting that this was a physiological adaptation that could be at least partly learned by the tourist children that were used as a control for the study.

So could we create superhumans by rigorously teaching children all these different tricks instead of genetic engineering?

Re:'Physiological Adaptation'

[FroMan]

That suggests the Moken learn the skill in childhood and do not simply inherit it as an inborn reflex.

Not evolution: (from the article) That suggests the Moken learn the skill in childhood and do not simply inherit it as an inborn reflex.

This is a form of adaptation to their environment.

Evolution is a trait that is passed on through genetics from one generation to another.

Personally I see evolution and survival of the fittest as two separate catagories though. Evolution is mutations (which add to the set of genes), where survival of the fittest is removal of the "bad" (genes which leave the carrier at a disadvantage, which can be localized to area though) genes from the gene pool.

Re:Nice theory, but... no.

[Hellraisr]

I wonder if it is possible that the brain is retrained that when the pupils go to that level of dilation, it triggers an alternately-learned method of processing the information the eyes give it.

trying it at home

[chloroquine]

As a curious person (who wishes that she too had the "flexibility of a salamander"), I'm tempted to go home and try this all out in the bathtub. But I'm not sure how I could measure the diameter of my own pupil.

It does strike me that the article initially tries to persuade one that this is a genetic trait, and then sneaks in the possiblity of a learned behavior. I think that this is a little cheap.

And that is why when the post asks me who I am, I am a 57 year old man from Washington DC. 20002 is my favorite made up zipcode.

Re:'Physiological Adaptation'

[paulthomas]

You are a little off.

Evolution (macroevolution specifically) is the emergence of desirable traits for a specific environment due to differential reproductive success, more commonly known as natural selection.

Natural Selection occurs when any or all of the rules of Hardy-Weinberg Equilibrium are broken.

Essentially, when something is less fit for an environment it is less likely to live long enough to reproduce. What makes up these genetic differences to begin with include Mutations, Genetic Drift, and Migration, among other factors.


Competition for limited resources is the key.

A nice google search for your learning pleasure.