In this extraordinary adaptation strategy, Thailand’s Moken sea gypsies can see twice as clearly underwater by controlling the size of their pupils. What was generally considered an automatic reflex for the rest of us is now thought to be something that any child under 5 could learn how to do.
From a study called Superior Underwater Vision in a Human Population of Sea Gypsies by Dr. Anna Gislén:
The Moken may learn to do this due to their extensive use of their eyes in water, where accommodation and concurrent pupil constriction is necessary for them to see the items they gather for food. It should then be possible for all humans to learn to see better underwater. But because sea gypsies have lived by and off the sea for thousands of years, evolution may also have favored those who had intrinsically better underwater accommodative powers. The ability to see well underwater could have become a genetic trait. Another possible explanation is that accommodation underwater is a side effect of the diving response; the parasympathetic nerves that control this reflex also control pupil constriction.
Read more at National Geographic.
In the archives: more swimming and these extreme eye closeups.
In this beautifully illustrated lesson from TED Ed, science writer and educator Carl Zimmer explains some answers to the question, How did feathers evolve?
From his article in National Geographic:
Most of us will never get to see nature’s greatest marvels in person. We won’t get a glimpse of a colossal squid’s eye, as big as a basketball. The closest we’ll get to a narwhal’s unicornlike tusk is a photograph. But there is one natural wonder that just about all of us can see, simply by stepping outside: dinosaurs using their feathers to fly.
With animation by Armella Leung, see how today’s birds are related to the dinosaurs of the past, and how fossils with feathers have helped us understand that connection.
Related viewing: evolution, dinosaurs, birds, flying, and a robot that flies like a bird.
Karl Sims is a digital media artist, computer graphics research scientist, and software entrepreneur. His influential artificial life computer animations, like this one from 1994, were programmed as virtual creatures that simulated evolution through genetic algorithms:
This video shows results from a research project involving simulated Darwinian evolutions of virtual block creatures. A population of several hundred creatures is created within a supercomputer, and each creature is tested for their ability to perform a given task, such the ability to swim in a simulated water environment. Those that are most successful survive, and their virtual genes containing coded instructions for their growth, are copied, combined, and mutated to make offspring for a new population. The new creatures are again tested, and some may be improvements on their parents. As this cycle of variation and selection continues, creatures with more and more successful behaviors can emerge.
The creatures shown are results from many independent simulations in which they were selected for swimming, walking, jumping, following, and competing for control of a green cube.
Our Story in 1 Minute:
A tapestry of footage tracing the cosmic and biological origins of our species, set to original music.
So so, so many related videos to dive further into these quick clips from MelodySheep. From the archives: the Big Bang, the moon, atoms, evolution, dinosaurs, nature, animals, culture, architecture, technology and space.
The Tube-Lipped Nectar Bat and the flower of the plant species Centropogon Nigricans, both of Ecuador, are very unique. Why? Because without this specific bat to pollinate this specific flower, the flower wouldn’t exist. As the bat drinks the flower’s nectar, the flower’s pollen dusts its head and face and is delivered to the next flower the bat visits.
And why is this particular bat so important to this long-fluted flower? Because this recently-discovered bat has a tongue that’s 150% the site of its body length! It keeps its tongue in its rib cage and then uses it to reach deep into the flower for its sweet nectar. From LiveScience:
[Nathan] Muchhala [of the University of Miami] suspects the bell-shaped flower and this nectar bat co-evolved, or influenced each other and evolved side-by-side. “This bat was just discovered [in 2005], and now we’ve observed a very unique relationship with a local flower,” Muchhala said.
To confirm, he plans to measure snout length of tube-lipped nectar bats in different areas. If the bats have shorter tongues in areas where the local flowers have diminutive tubes and longer tongues with lengthier flowers, the finding would support co-evolution.
One more note on the video: the National Geographic Untamed Americas team cut a small hole in the flower and stuck a high speed camera in it to capture the bat’s tongue on video. It’s incredible first-time footage of a bat that no one knew existed just a few years ago.