This Ancient Crab Had Unusually Huge Eyes

To figure out how Callichimaera used its eyes, Ms Jenkins and Dr Luque used the abundance of Callichimaera specimens available to put tog...


To figure out how Callichimaera used its eyes, Ms Jenkins and Dr Luque used the abundance of Callichimaera specimens available to put together a growth sequence. They compared this with 14 living species from the entire crab family tree. They were surprised to find that, unlike other crab species, Callichimaera retained its large eyes into adulthood.

In fact, their calculations showed that the compound eyes of Callichimaera grew faster than those of modern crabs sampled by the team. At their final size, their eyes took up about 16% of their body, the equivalent of a person walking around with eyes the size of a football.

Animals with compound eyes have an essentially pixelated view of the world, Ms Jenkins said, with each facet of the eye delivering a distinct pixel. The higher the number of pixels, the sharper the vision. The team’s analysis of Callichimaera’s eyes suggests it had unusually sharp vision for a crab – closer to efficient, light-eyed predators like dragonflies and mantis shrimp.

“Whatever this animal is doing, it must have been actively using such large eyes,” Dr. Luque said. “They are a huge drag in the water and they are vulnerable. So whatever disadvantages exist for such large eyes, they should be nothing compared to the advantages.

When combined with the paddle legs and streamlined body, Dr. Luque said, those powerful, fast-growing eyes suggested that adult Callichimaera fed on smaller creatures. And they did this by retaining their predatory larval form until adulthood, rather than making the final transformation into the flat, scuttled form favored by other crabs.

Callichimaera is also the youngest known fossil arthropod with both eyes and preserved neural tissue. Most brain-fossilized arthropods come from sites half a billion years old, where good insight into an animal’s visual processing system is rare. “Usually you can find elements of the brain, but the eyes are gone, or vice versa. But Callichimaera has both,” Dr. Luque said.

The site that produced Callichimaera probably has many more secrets to share.

“There’s a huge void in the fossil record because we don’t collect enough fossils or do a lot of fieldwork in the tropics,” Dr Luque said. “Usually these places are covered with vegetation and the rocks weather very quickly. Finding such exquisite preservation opens up new avenues for studying the fossil record with fresh eyes. No pun intended.”

Source Link

COMMENTS

Name

Africa,958,Americas,4376,Art & Culture,16185,Arts,6816,Arts & Design,1921,Asia,3601,Automobile,573,Baseball,839,Basketball,684,Books,4230,Business,5708,Celebrity,2633,Cricket,648,Crime,158,Cryptocurrency,2171,Dance,716,Defense,836,Diplomatic Relations,2496,Economy,1397,Editorial,260,Education,1517,Elections,308,Energy & Environment,3193,Entertainment,23704,Environment,3973,Europe,4559,Faith & Religion,235,Family & Life,817,Fashion & Style,3673,Finance,21903,Food & Drink,4148,Football,1312,Games,97,Gossip,10289,Health & Fitness,4499,Health Care,969,Hockey,273,Home & Garden,920,Humour,994,Latin America,49,Lifestyle,18590,Media,527,Middle East,1758,Movies,2056,Music,2981,Opinion,4089,Other,13222,Other Sports,5489,Political News,11324,Political Protests,2324,Politics,18872,Real Estate,2310,Relationship,106,Retail,3116,Science,2979,Science & Tech,11206,Soccer,385,Space & Cosmos,453,Sports,13607,Technology,3801,Tennis,732,Theater,1972,Transportation,313,Travel,2856,TV,4026,US,1570,US Sports,1481,Video News,3531,War & Conflict,1069,Weird News,998,World,18230,
ltr
item
Newsrust - US Top News: This Ancient Crab Had Unusually Huge Eyes
This Ancient Crab Had Unusually Huge Eyes
https://static01.nyt.com/images/2022/01/25/science/23tb-crabeyes1/23tb-crabeyes1-facebookJumbo.jpg%20
Newsrust - US Top News
https://www.newsrust.com/2022/01/this-ancient-crab-had-unusually-huge.html
https://www.newsrust.com/
https://www.newsrust.com/
https://www.newsrust.com/2022/01/this-ancient-crab-had-unusually-huge.html
true
732247599994189300
UTF-8
Loaded All Posts Not found any posts VIEW ALL Readmore Reply Cancel reply Delete By Home PAGES POSTS View All RECOMMENDED FOR YOU LABEL ARCHIVE SEARCH ALL POSTS Not found any post match with your request Back Home Sunday Monday Tuesday Wednesday Thursday Friday Saturday Sun Mon Tue Wed Thu Fri Sat January February March April May June July August September October November December Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec just now 1 minute ago $$1$$ minutes ago 1 hour ago $$1$$ hours ago Yesterday $$1$$ days ago $$1$$ weeks ago more than 5 weeks ago Followers Follow THIS PREMIUM CONTENT IS LOCKED STEP 1: Share to a social network STEP 2: Click the link on your social network Copy All Code Select All Code All codes were copied to your clipboard Can not copy the codes / texts, please press [CTRL]+[C] (or CMD+C with Mac) to copy Table of Content