Off the scale - new species of gecko with tear-away skin
A new species of gecko which evades predators by shedding its massive scales has been discovered by scientists working in Madagascar.
The species, named Geckolepis megalepis by the team of American German and Colombian researchers, is a type of fish gecko.
It has the largest scales of any gecko and skin specially adapted for tearing away at the slightest touch. The scales can grow back without scarring in a few weeks.
In fact, they are so adept at shedding scientists have had to use bundles of cotton wool to catch them in the past so they wouldn’t shed all their scales.
And the ease with which their scales come away makes describing and identifying the species a ‘nightmare’ according to the researchers because the scale pattern is one of the main ways to tell species apart.
In the end they decided to resort to using micro-CT scans to get a 3D picture of their skeletons, and were able to identify some skull features that establish these geckos as a new species.
“This octopus was NOT impressed when I interrupted its morning feeding stroll during my scuba dive in Melbourne, Australia. It blew itself up like a parachute multiple times to try to intimidate me, before trying to torpedo me like a bowling ball! Octopuses are beautiful, intelligent creatures and this one was using its most creative methods of self defense. Or maybe it was just hungry and angry at the same time (= hangry?)
Lobster Jr. figured out the suspended moss balls so much quicker than our old lobster. He also spent most of his time hanging from the bottom munching on the moss.
Cephalopods are quick-change artists. Like a living LCD screen, their skin can flicker and flash, or create complex patterns for camouflage and communication. Layers of specialized skin cells interact to match the environment’s color and texture.
These are, in my opinion, the most majestic animals currently on this earth.
Here’s a video of them mating from my old PI Roger Hanlon.
omg lol a whole paragraph of this got deleted (the paragraph with the answer to your question). They can grow up to a meter in total length, or about 50 cm if you only measure the mantle. WHICH IS CRAZY and swimming with one of these animals is #1 on my bucket list.
Diver shot an incredible footage of two octopuses fighting. The brawl lasts for almost a minute before the larger specimen overpowers its rival, killing it with a bite from its fearsome beak before dragging its lifeless corpse away into the darkness.
6 days old, already more than 8000 views on youtube !
is it cannibalism ?
Many sources talk about cannibalism. The dailystar use for example the title: “INCREDIBLE footage shot by a scuba diver shows the moment an octopus killed and ate its rival during an underwater fight to the death”.
To me, the video is not crystal clear: the larger octopus definitely uses its beak to administer the final blow, but after that it seems more likely that its transports the dead corpse. If you watch closely, the corpse is located at the tips of the tentacles, not inside the octopus’ mantle. So not cannibalism.
In [most] cases, the predator octopus was much bigger […]. Once captured and dead, the prey was transported to the den which in turn was plugged with stones of different sizes. The predator began to eat its victim by the tips of the arms.
So even if we didn’t witness actual cannibalism, the act could have happened afterwards.
Is cannibalism disgusting/pure barbarism ?
In our case, I would definitely say no. It is actually very intelligent and down-the-earth. Indeed: 1) the other octopus is already dead anyway, 2) octopuses are higher per-gram in protein than mussels, 3) opening mussels and capturing other small preys is tricky and energy consuming.
So it seems logical not to let the corpse drift on the floor for someone else to eat, but to eat it oneself. Right ?
Don’t look now, but this spineless sea creature may be able to count better than your toddler.
Cuttlefish need to be savvy if they want to eat. They’re always on the lookout for shrimp, fish or crabs. When a cuttlefish spots a potential victim, it shoots out two specialized, sucker-bearing tentacles and nabs it. Since these hunters have to make constant judgments about which prey are worth targeting, it would make sense for them to have advanced cognitive skills—say, the ability to count.
To find out whether this was true, Tsang-I Yang and Chuan-Chin Chiao, of Taiwan’s National Tsing Hua University, brought some Sepia pharaonis cuttlefish into the lab for a math exam.
The researchers hatched cuttlefish eggs and waited until the animals were a month old. Then they started testing the young cephalopods. In each test, a cuttlefish waited on one end of a tank, and researchers lowered a two-chambered box with clear walls into the other end. A partition jutted out from the center of the box toward the cuttlefish. As it swam toward the apparatus, the cuttlefish would have to make a choice between one chamber and the other.
As soon as the cuttlefish made its decision and veered toward one side of the box, the researchers yanked the apparatus back out of the water. (This was likely annoying to the cuttlefish, but they got fed at the end of the testing session.)
To see how well the animals can count, the researchers put different numbers of shrimp into each of the box’s chambers, ranging from 1 to 5. If there were 5 shrimp in one side of the box and just 1 in the other, the choice ought to be easy. But could cuttlefish reliably choose 2 shrimp over 1, or 3 shrimp over 2? What about 5 over 4?
The scientists tested 54 cuttlefish. As expected, the animals had no problem picking a bunch of shrimp over a single shrimp. But they also passed every other test they were given. Cuttlefish were significantly more likely to pick the side of the box with more shrimp, even when choosing between 4 and 5.
Cuttlefish took longer to make these decisions as the ratios between the numbers got smaller (for example, 5 to 4 versus 4 to 3). Chiao says this is evidence that the cephalopods were actually counting the shrimp on each side, rather than judging the quantities at a glance.
Further experiments ruled out other possible explanations: Rather than counting, do cuttlefish just look for a denser batch of shrimp? No, because when researchers crowded small numbers of shrimp into tighter spaces to increase their density, the cuttlefish still picked the bigger number. Do cuttlefish simply seek out the wiggliest pile of prey? No again, as the researchers showed using boxes of dead shrimp.
Math isn’t the only factor influencing a cuttlefish’s decisions, though. Cuttlefish prefer live victims, and when researchers offered their subjects 1 live shrimp or 2 dead ones, they chose the former. When offered one big, fat shrimp or two smaller shrimp, hungry cuttlefish took the big one—but cuttlefish that had already eaten chose the two small shrimp. This might be because the big shrimp is a more tempting prize, but riskier for a young hunter to grapple with. For a cuttlefish who isn’t especially hungry, it might not be worth the risk.
Chiao says he wasn’t surprised by how well the cephalopods performed.
“We know that [the] cuttlefish has a complex brain and a sophisticated neural system,” he says. “Cuttlefish have to search for food constantly, so having number sense is important for their life.” Although the experiments stopped at 5 shrimp, Chiao suspects cuttlefish might even be able to count a little bit higher.
Similar research in year-old humans showed that they could judge the difference between 1, 2 or 3 items, but failed when quantities got any bigger. Rhesus macaques could judge between numbers going up to 4, but no higher. So this study, the authors write, “implies that cuttlefish are at least equivalent to infants and primates in terms of number sense.”
The clever cephalopod was spotted in the Adriatic Sea, off the Dalmatian coast, Croatia, before digging itself into the ideal hiding spot. How it sinks into the floor is quite a show. More details here.
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