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DNA that does nothing?

It seems that most of our DNA is dormant. It doesn’t encode for protein production. Some of this supposedly dormant DNA has recently been shown to have important functionality, but there still seems to be much more information present than is used.

Here’s an article on the debate over how much of our DNA is functional.

Is Most of Our DNA Garbage?

Here’s an article on gene sequences that appear to have come from other organisms, entering our genetic code through horizontal gene transfer.

Humans may harbor more than 100 genes from other organisms

Here’s an article on DNA sequences that have been written into our DNA by viruses, some of which might still be capable of making us sick.

An ancient retrovirus has been found in human DNA – and it might still be active

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Not how we’d do it

Evolution creates designs in ways that human engineers probably wouldn’t. We probably wouldn’t use eyes to grow a brain, or pseudo-gill-slits to grow a face, but evolution does.

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When eyes are a problem

Sometimes, evolution can take it back. Many cave dwelling animals have lost their eyes. Theories as to why this happen range from genetic drift, to mutations that improve other senses interfering with the proper development of eyes, to the energy cost of growing and maintaining vision. I suspect that it has to do with how easily injured eyes are when they don’t work. I’ve never seen that brought up by scientists; maybe you have to go blind to get it.

Here’s an article on the kiwi bird and how it may be losing its sight as a species. Special thanks to @seeingwithsound for the article and pointing me to this topic.

New Zealand’s iconic kiwi birds may be losing their sight

Here’s an article on changes in the brains of sightless animals.

Thanks to evolution, blind cave-dwellers are rapidly losing the visual parts of their brains

Here’s a paper on animals that have given up eyes, and how and why they may have done so.

Evolution of eye development in the darkness of caves: adaptation, drift, or both?

Here’s an article on blind cave fish that includes a video.

How This Cave-Dwelling Fish Lost Its Eyes to Evolution

And an article on how the offspring of blind cave fish can regain their sight.

Blind Cavefish Can Produce Sighted Offspring