Look at this squid's eye. Just look at it. See anything eerily familiar?
Squid, along with the rest of the family Cephalopoda, haven't shared a common ancestor with us vertebrates in some 500 million years—long before the evolution of our camera-like eyes. And yet, there the cephalopods are, flagrantly swimming about with eyes that use a lens to project an image onto a retina. Call it Squid Eye for the Vertebrate Guy. So, how's it work?
Convergent evolution, my friends. Convergent evolution. We happened to hit on similar solutions to the same problem of sight, even though the eyes of vertebrates and cephalopods evolved separately, in very different ways, at different times. Today, we can see that legacy in cephalopod and vertebrate fetal development. With vertebrates, the eyes grow on stalks, reaching out from the brain. In cephalopods, the eyes start as a clumping of cells on the surface of the skin and reach backwards, into the head, to make brain contact. Similar destinations. Very different road maps.
This lovely illustration—featuring dissections of the head, funnel, mantle and eye of a Thaumatolampas diadema—comes from The Cephalopoda Part I: Oegopsida and Part II: Myopsida, Octopoda Atlas written in 1910 by zoologist Carl Chun following a German expedition to the Indian, Atlantic and Great Southern oceans.
You can see more of Chun's detailed, passionate illustrations at the BibliOdyssey blog.
Image: Some rights reserved by peacay
To demonstrate the Magnus effect, YouTuber PeterSripol grabbed a couple of KFC buckets and tricked out an RC plane. The resulting trial and error is mostly the latter.
One of the weirdest places in Antarctica is Blood Falls, a five-story cascade of blood-red liquid pouring from Taylor Glacier. Researchers finally traced its source: a saltwater lake millions of years old trapped under the glacier.
Fetal lambs survived for weeks in an experimental artificial womb, and scientists hope that the breakthrough could lead to new treatments for premature babies and perhaps the dreamed-of machine utopia where humans are kept mindlessly writhing in translucent plastic sheaths filled with psuedoamniotic liquid. Physicians at the Children’s Hospital of Philadelphia placed fetal lambs into […]
If you want to work in tech, but don’t have any desire to code web apps to help businesses sell things to other business, you might want to consider a career in cybersecurity. Judging from the apparent complete infiltration of Russian hackers in American cyberspace, it seems fair to speculate that there’s a major shortage of […]
All moms are different. But all moms like getting flowers on Mother’s Day, and that’s a fact (not, however a fact we can document in any fashion.) Instead of getting chewed out for forgetting to call her on the second Sunday of May, you can take care of it ahead of time with Teleflora’s flower […]
Yeah, Bluetooth audio is pretty common these days, so why should you care about these earbuds? Look how happy that woman up above looks. She’s got FRESHeBUDS in. Boom. There’s your reason. She’s also at the beach and it appears to be a very nice day.But for the sake of promotion, wireless earbuds are fast becoming the […]