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Could there be a reasonable case within the next billion years for a non-arthropod to evolve compound eyes?


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I was wondering why certain bugs seem to be the only animals on the planet that evolved compound eyes, and I'm guessing luck did play a big role in it, but I was also trying to think of where a large non-bug animal would ever need to have that exception kind of resolution and field of view at the expense of a greater complexity of a delicate organ.

One possible environment I was thinking is a thriving ecosystem in a constantly snowy arctic environment. In an environment like that with lots of animals around but also lots of irrelevant snow, a predatory animal would need to sort out lots of tiny minute details in a short span of time, distinguishing between the fast-falling snow and animals that camouflaged with it like perhaps a hare, shrew or pika.

Edited by SFNQuestions
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A compound eye is horrible. Why develop a poor eye if you already have a good one with a lens and a high resolution retina?

A compound eye isn't horrible, it's just different. Clearly there's a good advantage to it if such an uncommon adaption has survived all these years. You are confusing the effectiveness of a compound eye for a much more general problem of insects that has nothing to do with a compound eye, and that's that insects typically have poor vision to begin with. Not to mention spiders still have eight eyes after all these millions of years. More eyes at once means more field of view and more detail and resolution, but the current mammals and reptiles typically lack it because it would be too inefficient for them to have a giant head full of a hundred eyes.

Edited by SFNQuestions
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Not all spiders have 8 eyes. In fact, from reading the Wikipedia entry, spiders developed away from the compound eye to eyes that can form images. This gives some spiders a 10-times improvement over the dragonfly, which has the best compound eyes of all insects.

 

Some mammals, like rabbits, have a 360° view with only two eyes. Why would they need more? Predators typically have a much smaller angle of view, because they benefit from focusing on smaller regions.

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Not all spiders have 8 eyes. In fact, from reading the Wikipedia entry, spiders developed away from the compound eye to eyes that can form images. This gives some spiders a 10-times improvement over the dragonfly, which has the best compound eyes of all insects.

 

Some mammals, like rabbits, have a 360° view with only two eyes. Why would they need more? Predators typically have a much smaller angle of view, because they benefit from focusing on smaller regions.

Okay I'm just going to say it again cause apparent you didn't see it: compound eyes aren't bad, they're different. They have their own unique advantages.

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I was wondering why certain bugs seem to be the only animals on the planet that evolved compound eyes,

 

Me thinks your "seeming" is kinda somewhat lacking in/of reasoned thought..

 

Both the mammalian eyes and the insect eyes are "compound" eyes ...... with the basic difference being ..... how they are, per se, "packaged".

 

Like delboy alluded to above, .... a compound eye with 10 thousand lenses and photoreceptors on the front, ..... or a compound eye with a single lens on the front and 10 thousand photoreceptors behind it.

 

To wit:

 

There are currently three known types of photoreceptor cells in mammalian eyes: rods, cones, and photosensitive retinal ganglion cells. The two classic photoreceptor cells are rods and cones, each contributing information used by the visual system to form a representation of the visual world, sight.

 

The human retina contains about 120 million rod cells and 6 million cone cells.

Read more @ https://en.wikipedia.org/wiki/Photoreceptor_cell

 

 

A truly remarkable sight would be to view .......

 

Life Through The Eyes Of The Mantis Shrimp

 

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Me thinks your "seeming" is kinda somewhat lacking in/of reasoned thought..

 

Both the mammalian eyes and the insect eyes are "compound" eyes ...... with the basic difference being ..... how they are, per se, "packaged".

 

Like delboy alluded to above, .... a compound eye with 10 thousand lenses and photoreceptors on the front, ..... or a compound eye with a single lens on the front and 10 thousand photoreceptors behind it.

 

To wit:

 

 

A truly remarkable sight would be to view .......

 

Life Through The Eyes Of The Mantis Shrimp

 

Semantics don't circumvent the fact that the consensus of biologists define the compound eyes of a fly differently than the simple eye of a mammal.

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Semantics don't circumvent the fact that the consensus of biologists define the compound eyes of a fly differently than the simple eye of a mammal.

 

The fact is, you do not speak for this biologist, ..... nor any biologist that I'm aware of.

 

And speaking biologically, ....

 

compound eyes - an eye consisting of an array of numerous small visual units, as found in insects and crustaceans.

 

simple eyes - a small eye of an insect or other arthropod that has only one lens, typically present in one or more pairs.

 

 

And mammalian eyes are not adjudged by biologists to be either compound or simple.

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The fact is, you do not speak for this biologist,

I don't need to speak for anyone, it's common knowledge.

 

 

And mammalian eyes are not adjudged by biologists to be either compound or simple.

Also wrong, a simple eye is just the general case that an eye contains a single lens and is extended to any animal, including humans https://en.wikipedia.org/wiki/Simple_eye_in_invertebrates

"The eyes of humans and large animals, and camera lenses are classed as "simple" because in both cases a single lens"

Edited by SFNQuestions
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I don't need to speak for anyone, it's common knowledge.

 

Also wrong, a simple eye is just the general case that an eye contains a single lens and is extended to any animal, including humans https://en.wikipedia.org/wiki/Simple_eye_in_invertebrates

"The eyes of humans and large animals, and camera lenses are classed as "simple" because in both cases a single lens"

 

 

My source says different.

 

Q: What is the difference between compound eyes and simple eyes?

 

A: Quick Answer

Compound eyes are essentially large clusters of simple eyes that are functionally capable of discerning images, whereas simple eyes only detect changes in light level. Compound eyes are found in many types of arthropods, and range from the relatively simple to the very complex. Regardless of their complexity, however, few arthropod eyes approach the acuity of vertebrate or cephalopod eyes, especially the keener vision of species, such as humans.

Continue Reading

 

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The arthropod eye is nothing like mammalian eyes with very different developmental and evolutionary histories. Conflating those serves no purpose. What you refer as "simple eye" most likely refers to the ommatidium which in itself is vastly different from the far more complex mammalian eye. That being said, in some ways arthropod eyes are in some way the consequence of certain developmental decisions (so to speak) including having a convex bulge as an optical unit.

Of course, in evolution there is little sense to try to predict complex traits and even with seemingly simple ones it is typically not quite possible (except, perhaps, under highly controlled conditions with very finely-tuned selective pressures). But it one can probably state clearly that at least in animals that have developed eyes there is little reason to assume that they will change to a completely different anatomical unit. The developmental changes required would be too massive (presumably).

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When animals originally evolved the compound eyes, they were exploiting a niche that was vacant at the time.

Seeing animals were deriving great advantage over their rivals by evolving eyes, of the different sorts.

 

Now, the situation is entirely different. Animals that have no eyes at present, wouldn't get the same advantage from an eye, because that niche is well and truly exploited by animals that can see much better than they possibly could.

 

So I think the answer to the OP is a highly likely no. Not unless the clock was reset, and all seeing animals went extinct.

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