Thanks to Ocean Wavelengths for having me on the podcast to talk about my work with Green Fins and the small steps we can take that can have big positive impacts for coral reefs when we’re diving or snorkeling! Only 12 minutes and who knows, you might learn something new!
Modern fish make up a huge part of Earth’s ecosystems, and cover a lot of niches. Predators, omnivores and herbivores are all found in this diverse group. Millions of years of adaptation has sculpted their bodies into the various forms and shapes we see today.
Looking beneath the surface of a fish’s skin can reveal a lot about the ecology of fish – the most diverse group of vertebrates on Earth. Use our image sliders to see under their scales.
The E/V Nautilus team are in Papahānaumokuākea Marine National Monument seeking out new discoveries in biology, geology, and archaeology. They came across this Gulper Eel (Eurypharynx pelecanoides) showing off for the camera!
“Its pouch-like mouth can inflate in an instant, scooping up much larger prey just like a pelican–and giving it that muppet-like look! This gulper eel was likely a juvenile, as this species can grow up to three feet in length.”
So I was looking up a certain kind of cellular automata on Wikipedia out of curiosity, and then I ended up seeing a link for something called “billiard ball computers”.
So basically it’s a theoretical construction to show nature has results that can be reversible or something. You do have to let the billiards be frictionless, though. So it’s not like you could implement this in real lif-
Wait,, just look at the pictures they have though. The captions refer to crab groups as “swarm balls”, which is a very endearing term IMO.
Unfortunately, these gates take up a lot of space, so to do big computations you’d need lots of crabs and several hundred feet of cardboard.
Me: You want to google something? Sure, let me fire up my crabputer…
Me: *dumps a bucket of soldier crabs into an acre-wide rat maze*
Me: it takes them a while to find the internet, so sit tight for a bit.
When I was a child, my father would take me trout fishing, and I spent hours marveling from the riverbank at the trouts’ ability to, seemingly effortlessly, hold their position in the fast-moving water. As it turns out, those trout really were swimming effortlessly, in a manner demonstrated above. The fish you see here swimming behind the obstacle is dead. There’s nothing powering it, except the energy its flexible body can extract from the flow around it.
The obstacle sheds a wake of alternating vortices into the flow, and when the fish is properly positioned in that wake, the vortices themselves flex the fish’s body such that its head and its tail point in different directions. Under just the right conditions, there’s actually a resonance between the vortices and the fish’s body that generates enough thrust to overcome the fish’s drag. This means the fish can actually swim upstream without expending any energy of its own! The researchers came across this entirely by accident, and one of the questions that remains is how the trout is able to sense its surroundings well enough to intentionally take advantage of the effect. (Image and research credit: D. Beal et al.; via PhysicsBuzz; submitted by Kam-Yung Soh)