{"id":19807,"date":"2022-11-09T20:00:03","date_gmt":"2022-11-09T19:00:03","guid":{"rendered":"https:\/\/www.sciencefocus.com\/?p=130568"},"modified":"2022-11-10T10:48:10","modified_gmt":"2022-11-10T09:48:10","slug":"angry-octopuses-caught-hurling-silt-shells-and-algae-at-one-another","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcsciencefocus\/rss_feed\/angry-octopuses-caught-hurling-silt-shells-and-algae-at-one-another\/","title":{"rendered":"Angry octopuses caught hurling silt, shells and algae at one another"},"content":{"rendered":"

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By Jason Goodyer\n \t\t<\/p>

Published: Wednesday, 09 November 2022 at 12:00 am<\/p>

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Octopuses have been observed throwing around debris, sometimes at one another<\/a> and especially when they show visible signs of anger.<\/p>\n

A team of researchers based at the University of Sydney recorded the behaviour of a group of 10 common Sydney octopuses in Jervis Bay, New South Wales, Australia over several days in 2015 and 2016 using underwater cameras.<\/p>\n

The octopuses were seen gathering up material such as silt, shells and algae and propelling it using a jet of water squirted from their siphon. In this manner they were able to fire material several body lengths away.<\/p>\n

The researchers spotted 102 instances of the behaviour across 24 hours of footage spread throughout the observation period.<\/p>\n

Around half of the throws occurred during interactions with other octopuses, such as arm probes or mating attempts and around 17 per cent of the objects thrown hit other octopuses.<\/p>\n

This suggests that the octopuses are capable of targeted throws towards other individuals \u2013 a behaviour that has only been previously observed in a few non-human animals, the researchers say.<\/p>\n

\nhttps:\/\/media.immediate.co.uk\/volatile\/sites\/4\/2022\/11\/8-Octopus-throw-video-Credit-Peter-Godfrey-Smith-David-Scheel-Stephanie-Chancellor-Stefan-Linquist-Matthew-Lawrence-28666f8.mp4<\/a><\/video><\/div>\n

Although it is unclear exactly why the octopuses are throwing the material around, the researchers noticed that the animals that changed their skin to darker colours \u2013 a behaviour usually interpreted as a display of aggression \u2013 did so more often.<\/p>\n

\u201cI\u2019d speculate that a lot of the targeted throws are more like an attempt to establish some \u2018personal space\u2019, but this is a speculation, it\u2019s very hard to know what their goals might be,\u201d said lead researcher Professor Peter Godfrey-Smith<\/a>, of the University of Sydney.<\/p>\n

\u201cOctopuses that displayed uniform colour, dark or medium, threw significantly more often with high vigour, while those displaying a \u2018pale and dark eyes\u2019 pattern threw more often with low vigour.<\/p>\n

\u201cThrows by octopuses displaying uniform body patterns, especially uniform dark patterns, hit other octopuses significantly more often than in other body patterns.\u201d<\/p>\n

Read more about cephalopods:<\/strong><\/p>\n