Jan 13 (Friday the 13th!) You must be tiring of me saying this: yet again I've been lax about sending out my articles here. Five that I know of. Sorry, then, for inundating your mailbox!
The first of these was prompted when I found a short video clip of an octopus. And this octopus was doing something quite unexpected, at least to me: throwing something at another octopus. I was just charmed, though maybe the target octopus didn't react like that. Why did that happen? Read on. This was my Mint column for Friday December 16. Writing it also gave me the chance to remember Ollie Taylor, an eccentric, sharp and immensely likeable man. I once watched him practicing playing the drums expertly in his basement - and at the time, he was losing his eyesight. Go well, Ollie. In this corner, an octopus throws, https://www.livemint.com/opinion/columns/in-this-corner-an-octopus-throws-11671125201124.html cheers, dilip --- In this corner, an octopus that throws Many years ago, Ollie Taylor came visiting from the USA. It was the first trip to India for this old pal of my father's, and he was delighted by things that were so different here. Example: cricket, and he asked me to take him to a match. The Bombay Ranji team - with Tendulkar, who scored 204 - were playing the visiting Australians right then. Ollie and I took a bus into town to spend the second day at the Brabourne Stadium. In a word, he was charmed. He couldn't get over the whites, the pace and rhythm of the game, the arcane rules. At home that evening, he handwrote a note about the day to his wife back in the US, and gave it to me to type up and email to her. Doing that, I found that one thing about the game had particularly fascinated Ollie: the way fielders ran after the ball, picked it up and threw it back to the wicketkeeper. "They're impossibly graceful," he wrote. "Like watching a ballet." Throwing a ball, like ballet! I had never thought of it that way, but Ollie made me look at the game afresh. It is indeed like ballet. I haven't thought about Ollie and that delicious comparison for years. This week, I did: prompted, of all things, by some findings about octopuses (In the line of fire, Godfrey-Smith, Scheel and others, 9 November 2022, https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0276482). Indeed, the eight-limbed creatures that live on sea-floors. What might octopuses (octopi?) possibly have in common with Ollie, or the game of cricket? Only this much: recent research shows that octopi throw things about, including at ... well, hold on to that thought for a while. I'm not sure they are graceful in their throws, or if they might remind Ollie of ballet. But that they throw things, there seems to be no doubt. How do we know this? A team of researchers in Australia sank underwater cameras into Jervis Bay, about 150km east of the capital, Canberra. A particular species of octopus is found in great abundance in Jervis Bay: Octopus tetricus, known as the Common Sydney Octopus, but also the "gloomy" octopus. I don't know if that latter name is a reference to the animals' mindsets when living among their compatriots, or something else altogether. The thing is, octopuses in general are not overly social animals anyway. As the paper by these researchers notes: "They hunt alone, may fight on encounter, and can cannibalize each other." Maybe they are gloomy. But they are also "dextrous manipulators of objects." They put all eight arms to work to build the dens they occupy and keep them in shape, using all kinds of material and objects. One species, for example, is known to handle discarded coconut shells. The gloomy octopus seems to like rocks and reefs when it is breeding, but otherwise prefers to live in the softer, sandier surrounds of the ocean floor. That means these animals must build themselves some kind of shelter. What's interesting about their Jervis Bay habitat is that only certain sites on the floor offer both appropriate shelter and plentiful food. So the octopuses are not evenly spread around the Bay. Instead, they occupy "high-density" sites: each one a "sharply limited patch of suitable habitat" that is home to many gloomy octopuses. Does that mean we can expect more interaction between these otherwise anti-social creatures? Well, yes, and that's putting it mildly. As the researchers report, during their observations they watched a maximum of about 6 octopuses an hour. Among these, "interactions were frequent; from 11 up to 234 per hour, [with an] average of 73." Not so anti-social, after all. But when the researchers went over their hours of octopus footage, they found something surprising about these interactions. Among everything the animals did - foraging for food, eating, building their dens - one specific behaviour was unexpected and, for animals in general, unusual. They threw things. They threw things like empty shells, silt and algae. Typically they would release one of these objects with an arm. From a siphon under their arms, they would then shoot a strong jet of water at the object, directing it where they wanted. Undoubtedly, some of this was just to get rid of things and material they no longer needed (wanted?). By itself, discarding stuff isn't unfamiliar behaviour among animals. Ants, for example, dig into the ground to build their extensive nests, and discard the earth that's excavated outside. This is how the astonishing structures we call anthills are formed. But a still closer look at the footage showed that there was more than simple discarding going on in Jervis Bay. The octopuses were often seen throwing things while interacting with each other. In fact, what they throw like this often hits other octopuses. In one clip, an octopus seems to extend an arm towards the one who's about to throw something, as if to ward off the object. It's an uncannily human gesture. It may also be more evidence to support what the researchers couldn't help conclude after this experiment: octopuses often throw stuff at other octopuses. Different features of these throws lend weight to this fascinating finding. As the scientists wrote: * "Throws in interactive contexts were more vigorous than others, and more often used silt, rather than shells or algae." At least they didn't seem to want to hurt their compatriots with solid objects like shells. * "High vigour throws were more often accompanied by uniform or dark body patterns than other throws." This suggests that the more high-powered the throw, the more likely it is to be deliberate rather than random. * "Some throws were directed differently from beneath the arms and such throws were more likely to hit other octopuses." Yes, they are aiming at their compatriots. And to go with that last point, the octopuses that were hit often behaved in ways you might resort to if someone throws stuff at you. They paused their movements, or moved away, or raised an arm in that uncannily human way. Some ducked. Of course they did. If there are octopuses that throw things, there have got to be octopuses that duck. I'd love to know what Ollie Taylor makes of that. -- My book with Joy Ma: "The Deoliwallahs" Twitter: @DeathEndsFun Death Ends Fun: http://dcubed.blogspot. -- You received this message because you are subscribed to the Google Groups "Dilip's essays" group. To unsubscribe from this group and stop receiving emails from it, send an email to dilips-essays+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/dilips-essays/CAEiMe8pN%2BLq2FP7N0CaWNDkhsk9LyxjT91TEDhgRHA2dMM%3D9zQ%40mail.gmail.com.
