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clacke (clacke@libranet.de)'s status on Tuesday, 14-Mar-2023 23:36:42 JST clacke

The eye has evolved many times, over 40 times. But I think I've heard of a case where even the same animal evolved it twice. Like it'd have full-blown camera eyes but also a light-sensitive patch somewhere else on the body.

I'm not finding anything, has anyone else heard of this and can confirm it?

Not talking about the pineal gland.

In conversation Tuesday, 14-Mar-2023 23:36:42 JST from libranet.de permalink
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  pettter (pettter@mastodon.acc.umu.se)'s status on Tuesday, 14-Mar-2023 23:37:31 JST pettter
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  @clacke ..yeah I recall a story like that, but I don't know from where either
  
  In conversation Tuesday, 14-Mar-2023 23:37:31 JST permalink
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  chiasm (chiasm@mastodon.online)'s status on Tuesday, 14-Mar-2023 23:51:07 JST chiasm
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  @clacke (Oh, it's you again!) I thought I could find it but didn't. However, this is a fascinating overview of the evolution of the eye that I found instead (it should be open access?)... it might give you a lead!
  https://www.nature.com/articles/eye2017226
  
  In conversation Tuesday, 14-Mar-2023 23:51:07 JST permalink
  
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  clacke (clacke@libranet.de)'s status on Wednesday, 15-Mar-2023 00:06:08 JST clacke
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  - chiasm
  @chiasm Thanks! It gave me some search terms.
  
  Apparently having different stages of eyes happens all the time in arthropods, but we're not clear on which eye evolved from which, or if one might be an independent evolution.
  
  Some have simple eyes or eye spots that we're pretty sure evolved from a more complex faceted eye. Some have simole eyes that might have evolved independently from their faceted eyes. I think that's what the text is saying: "some taxa have secondarily developed simple eyes"
  
  en.wikipedia.org/wiki/Arthropo…
  In conversation Wednesday, 15-Mar-2023 00:06:08 JST permalink
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  clacke (clacke@libranet.de)'s status on Wednesday, 15-Mar-2023 00:09:12 JST clacke
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  "That suggests that the compound eye may have developed after the onychophoran and arthropod lineages split, but before the radiation of arthropods. This view is supported if a stem-arthropod position is supported for compound-eye bearing Cambrian organisms such as the Anomalocaridids. Yet another alternative is that compound eyes independently evolved, multiple times within the arthropods."
  
  Awesome.
  
  In conversation Wednesday, 15-Mar-2023 00:09:12 JST permalink
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  Mike McCabe (mikemccabe@mastodon.social)'s status on Wednesday, 15-Mar-2023 00:12:58 JST Mike McCabe
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  @clacke there’s the Tuarara, with it’s parietal eye: https://en.m.wikipedia.org/wiki/Tuatara
  In conversation Wednesday, 15-Mar-2023 00:12:58 JST permalink
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    Tuatara
    
    Tuatara (Sphenodon punctatus) are reptiles endemic to New Zealand. Despite their close resemblance to lizards, they are part of a distinct lineage, the order Rhynchocephalia. The name tuatara is derived from the Māori language and means "peaks on the back". The single extant species of tuatara is the only surviving member of its order. Rhynchocephalians originated during the Triassic (~250 million years ago), reached worldwide distribution and peak diversity during the Jurassic and, with the exception of tuatara, were extinct by 60 million years ago. Their closest living relatives are squamates (lizards and snakes). For this reason, tuatara are of interest in the study of the evolution of lizards and snakes, and for the reconstruction of the appearance and habits of the earliest diapsids, a group of amniote tetrapods that also includes dinosaurs (including birds) and crocodilians. Tuatara are greenish brown and grey, and measure up to 80 cm (31 in) from head to tail-tip and weigh up to 1.3 kg (2.9 lb) with a spiny crest along the back, especially pronounced in males. They have two rows of teeth in the upper jaw...
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  clacke (clacke@libranet.de)'s status on Friday, 17-Mar-2023 17:45:25 JST clacke
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  - Mike McCabe
  >
  
  @mikemccabe I'm here for the necroposting, friend. Leave a comment on something I posted 5 years ago and I'm all ears! 1 day later is *nothing*! ?
  
  In conversation Friday, 17-Mar-2023 17:45:25 JST permalink
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  Mike McCabe (mikemccabe@mastodon.social)'s status on Friday, 17-Mar-2023 17:45:26 JST Mike McCabe
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  @clacke you’ve probably moved on with your life :) but!
  I thought it was an interesting question to try out the new Bing chat with, here’s what I got.
  what are examples of animals with multiple types of eyes?
  
  In conversation Friday, 17-Mar-2023 17:45:26 JST permalink
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  Mike McCabe (mikemccabe@mastodon.social)'s status on Friday, 17-Mar-2023 17:45:27 JST Mike McCabe
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  @clacke
  Some animals have evolved to have multiple eyes. For example, the **four-eyed fish** has two eyes, but each eye is divided into two parts, allowing it to see both above and below the water at the same time¹. Some species of **scorpions** have an extra pair of eyes, giving them a total of 12³. *
  
  In conversation Friday, 17-Mar-2023 17:45:27 JST permalink
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  clacke (clacke@libranet.de)'s status on Friday, 17-Mar-2023 17:45:27 JST clacke
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  - Mike McCabe
  > For example, the **four-eyed fish** has two eyes, but each eye is divided into two parts, allowing it to see both above and below the water at the same time.
  @mikemccabe That's the exact one I was thinking of!
  
  In conversation Friday, 17-Mar-2023 17:45:27 JST permalink

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