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Octopi are interesting in that they evolved along their own path. The octopus eye has the wiring on the back, where it belongs, instead of on the front blocking some of the light, as most other animals with eyes do.

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They apparently also don't require crossing wires connecting each eye with the opposite brain hemisphere. Instead, the optic lobes are directly behind the eyes: http://cephalove.blogspot.com/2010/06/view-of-octopus-brain....

Also, their eye cells only detect black and white but they can probably “see” color by using non-circular pupils.

https://news.berkeley.edu/2016/07/05/weird-pupils-let-octopu...

The article you linked also speculates on the main topic of this thread:

> Intriguingly, using chromatic aberration to detect color is more computationally intensive than other types of color vision, such as our own, and likely requires a lot of brainpower, Stubbs said. This may explain, in part, why cephalopods are the most intelligent invertebrates on Earth.

The visual system was often cited by proponents of intelligent design as evidence of god. But the mammalian visual system is an absolute mess. Anyone who designed that would have been fired on the spot. The octopus visual system, on the other hand, is quite elegant and efficient. If there really were an intelligent designer, the implications would be worrying.

Curiously the same applies to imaging sensors. They used to be inverse (front-illuminated), for process reasons, but everse (back-illuminated) sensors have better sensitivity and lower noise (but are harder to manufacture).

A notable advantage of everse eye construction is the complete absence of a blind spot, which is where all the wiring passes through the sensor surface. (Image sensors never had that problem because they are connected at the edges).

Any indication if this backlit image sensor development was inspired by nature (the octopus here, for example) or was just an independent evolution of the technology?

Independent. Nobody would do Frontside illumination if it weren't a lot cheaper and easier because you very clearly lose out on light.

Indeed, the manufacturing is more difficult because the silicon has to be thinned after fabrication of the circuitry. The lucky feature of image sensors is that the image is actually shifted to the edges of the chip by an analog shift register mechanism. But they still need an electrode structure to make the shift register work, and the light has to pass through it in front-illuminated sensors.

The Oxford English Dictionary lists octopuses, octopi and octopodes (in that order); it labels octopodes "rare", and notes that octopi derives from the mistaken assumption that octōpūs is a second declension Latin noun, which it is not.

https://english.stackexchange.com/questions/270/what-is-the-...

If you are interested in the plurals of Octopus it is interesting also this note from the Merraim-Webster's site https://www.merriam-webster.com/words-at-play/the-many-plura...

It’s an interesting area.

http://science.sciencemag.org/content/313/5795/1914

The location of the ‘wiring’ changes the type of information gleaned from the light field. There is no ‘wrong,’ rather, a variation in local optimization.

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