Original image

Octopuses Change Colors to Intimidate Their Foes, Study Finds

Original image

Octopuses are well-known for being anti-social, but new research is proving they aren’t as reclusive as scientists previously believed. In fact, their knack for changing their appearance—long thought of as an effective way to hide—may also be a way they communicate with other octopuses, a new study finds. Research from Alaska Pacific University and the University of Sydney published in Current Biology indicates that the ability to change the hue of their bodies plays an important role in conflicts between octopuses.

The researchers studied a species called Octopus tetricus by setting up cameras in the shallow waters of Jervis Bay off the eastern coast of Australia. In more than 50 hours of video, they catalogued 186 octopus interactions, noticing a pattern in the social lives of the eight-tentacled creatures: They tend to turn dark colors when they feel aggressive.

The octopus in the background of the photo is adopting an aggressive posture, while the pale octopus in the foreground is being submissive.

When a dark-colored octopus approached another dark-colored octopus, the two were more likely to fight, whereas if a light-colored octopus met a dark octopus, the paler of the two was likely to scuttle off in retreat. Dark octopuses were more likely to stand their ground during a beef, while lighter octopuses were more likely to beat it.

In addition to dimming the color of their bodies, aggressive octopuses typically stand up tall and spread their web out in a position "nicknamed the Nosferatu pose,” making themselves look as large and forbidding as possible, while submissive octopuses will slink down.

This adds to previous research that found that octopuses can be social in captivity, even cohabitating in dens. The authors of the current study suggest that octopuses may behave more socially in areas where there’s a lot of food to be had, but limited places to hide. The growing body of evidence for octopus interactions (that don’t involve eating each other) “indicates that we should no longer consider octopuses as solitary and asocial,” they write.

[h/t: NPR]

All images by David Scheel

Original image
Big Questions
Why Do Cats Freak Out After Pooping?
Original image

Cats often exhibit some very peculiar behavior, from getting into deadly combat situations with their own tail to pouncing on unsuspecting humans. Among their most curious habits: running from their litter box like a greyhound after moving their bowels. Are they running from their own fecal matter? Has waste elimination prompted a sense of euphoria?

Experts—if anyone is said to qualify as an expert in post-poop moods—aren’t exactly sure, but they’ve presented a number of entertaining theories. From a biological standpoint, some animal behaviorists suspect that a cat bolting after a deposit might stem from fears that a predator could track them based on the smell of their waste. But researchers are quick to note that they haven’t observed cats run from their BMs in the wild.

Biology also has a little bit to do with another theory, which postulates that cats used to getting their rear ends licked by their mother after defecating as kittens are showing off their independence by sprinting away, their butts having taken on self-cleaning properties in adulthood.

Not convinced? You might find another idea more plausible: Both humans and cats have a vagus nerve running from their brain stem. In both species, the nerve can be stimulated by defecation, leading to a pleasurable sensation and what some have labeled “poo-phoria,” or post-poop elation. In running, the cat may simply be working off excess energy brought on by stimulation of the nerve.

Less interesting is the notion that notoriously hygienic cats may simply want to shake off excess litter or fecal matter by running a 100-meter dash, or that a digestive problem has led to some discomfort they’re attempting to flee from. The fact is, so little research has been done in the field of pooping cat mania that there’s no universally accepted answer. Like so much of what makes cats tick, a definitive motivation will have to remain a mystery.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at

Watch a School of Humpback Whales 'Fish' Using Nets Made of Bubbles 

Just like humans, humpback whales catch many fish at once by using nets—but instead of being woven from fibers, their nets are made of bubbles.

Unique to humpbacks, the behavior known as bubble-net feeding was recently captured in a dramatic drone video that was created by GoPro and spotted by Smithsonian. The footage features a school of whales swimming off Maskelyne Island in British Columbia, Canada, in pursuit of food. The whales dive down, and a large circle of bubbles forms on the water's surface. Then, the marine mammals burst into the air, like circus animals jumping through a ring, and appear to swallow their meal.

The video offers a phenomenal aerial view of the feeding whales, but it only captures part of the underwater ritual. It begins with the group's leader, who locates schools of fish and krill and homes in on them. Then, it spirals to the water's surface while expelling air from its blowhole. This action creates the bubble ring, which works like a net to contain the prey.

Another whale emits a loud "trumpeting feeding call," which may stun and frighten the fish into forming tighter schools. Then, the rest of the whales herd the fish upwards and burst forth from the water, their mouths open wide to receive the fruits of their labor.

Watch the intricate—and beautiful—feeding process below:


More from mental floss studios