"Don't tread on me" is a slogan of the deep sea, too.
- Octopuses are part of multispecific collaborative hunting groups with bottom-feeding fish.
- New research shows octopuses defending their territory by punching fish.
- The team believes this research helps reveal underlying game structures in the deep sea.
Why some angry octopuses punch fish<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="51bbb80fd93a2d9a93b7bd668ff47d55"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/Uf8QfPF6Q_E?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>An octopus body, Godfrey-Smith argues, in some sense transcends the brain-body divide—neither embodied cognition nor disembodied spirit. Rather, it's "all possibility." Nagel, according to Godfrey-Smith, flubbed the question: the octopus is like <em>something</em>, just nothing like a human, therefore making it difficult to even define. </p><p>Alas, we can't help but anthropomorphize. Octopuses might maintain a vastly different intelligence, yet like us, they've had to figure out how to survive in challenging environments. As a <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3266" target="_blank">new study</a>, published in The Scientific Naturalist, shows, they seem to do that, in part, by punching fish. </p><p>Our evolutionary success is due in large part to group fitness: we work together well. On occasion, we collaborate with other species to our mutual benefit, as with hunting dogs. The authors of this study point out that ocean life is filled with multispecific collaborative hunting groups, such as moray eels and groupers. Octopuses get in on this action as well. </p><p style="margin-left: 20px;">"Involving active recruitment and referential gestures, the nature of this relationship is mutually beneficial (byproduct mutualism); that is, both can increase their hunting success rate from the presence of the other species, which likely played an important role in the emergence of complex interactions between groupers and eels."</p>
Image sequence depicting the behavioral action of Octopus cyanea punching (white arrows) a yellow‐saddle goatfish (Parupeneus cyclostomus) partner during interspecific multicollaborative hunting.<p>Coral reef fishes have made bonds with other ocean life, such as octopuses, who chase prey within rocks and coral crevices while bottom-feeders scour the seafloor. Octopuses are known to tail groupers on hunting expeditions. As with any complex social network, however, life is not all mutual benefit. Tensions rise.</p><p>Recording instances in Israel in 2018 and Egypt in 2019, the team observed octopuses punching collaborating fish when things got heated. The goal appears to be moving the fish to a less advantageous location or simply telling them to scram. </p><p style="margin-left: 20px;">"Thus, from the octopus's perspective, punching serves as a partner control mechanism, the nature of which is dependent on the ecological context of the interaction, and on how the octopus benefits from inflicting costs on fish partners."</p><p>As Godfrey-Smith writes, octopus arms are partly self and partly non-self—each arm is, in a sense, autonomous. To extend a metaphor, breathing is autonomic yet we can also control it. So too each octopus arm travels on its own but also coordinates with the rest of the body. The central brain, he continues, is like a conductor, with each arm being an improvisational jazz player, paying attention to the structure of the song while meandering off when needed. </p><p>We will never know what it's <em>like</em> to be an octopus. Nature has branched intelligence in distinctly different directions. Perhaps we share common ground on the hunt for survival. The team believes that research on punching octopuses helps reveal underlying game structures in the deep sea. And maybe, in some form of interspecies solidarity, we can appreciate their method of defending territory. </p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank" rel="noopener noreferrer">Facebook</a>. His most recent book is</em> "<em><a href="https://www.amazon.com/gp/product/B08KRVMP2M?pf_rd_r=MDJW43337675SZ0X00FH&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee" target="_blank" rel="noopener noreferrer">Hero's Dose: The Case For Psychedelics in Ritual and Therapy</a>."</em></p>
The bizarre discovery could pave the way for advances in regenerative medicine for humans.
- In a recent study, scientists observed two species of sea slug that were able to self-decapitate, survive for weeks without organs, and regenerate entirely new bodies.
- The study authors proposed that the slugs are able to survive as severed heads because of the unique way they obtain energy from algae.
- While other animals engage in self-amputation (known as autotomy) to avoid predators, the study authors suggested that sea slugs might shed their bodies to avoid dying from parasites.
S. MITOH AND Y. YUSA/CURRENT BIOLOGY 2021<p>Still, scientists aren't exactly sure how kleptoplasty interacts with autotomy in sea slugs, and the authors noted that more research is needed to confirm what drives autotomy and body regeneration in the sea creatures. But despite the uncertainties, the new study shows that extreme forms of regeneration are possible in the animal kingdom.</p><p>As scientists continue to uncover the secrets of autotomy and regeneration in animals, it could pave the way for advances in <a href="https://www.frontiersin.org/articles/10.3389/fmed.2019.00011/full" target="_blank" rel="noopener noreferrer">regenerative medicine</a>, a field that aims to harness the body's natural healing mechanisms.</p><p style="margin-left: 20px;">"One day, patients will have access to regenerative medicine treatments that will circumvent the complications of organ donation," Sharlini Sankaran, executive director of Duke University's Regeneration Next Initiative, told <a href="https://medschool.duke.edu/about-us/news-and-communications/med-school-blog/future-regenerative-medicine" target="_blank">Duke University School of Medicine.</a> "We will be able to use our bodies' own innate repair mechanisms to eliminate the wait time, cost, and limited supply of organ transplantation. Instead of transplanting organs, we will know how to repair our own."</p><p>While there are significant differences between mollusks and mammals, the drivers of regeneration in sea slugs could provide clues as to how scientists might use approaches like stem-cell therapies to repair damage to cells, tissue and organs.</p>
The famous cognition test was reworked for cuttlefish. They did better than expected.
- Scientists recently ran the Stanford marshmallow experiment on cuttlefish and found they were pretty good at it.
- The test subjects could wait up to two minutes for a better tasting treat.
- The study suggests cuttlefish are smarter than you think but isn't the final word on how bright they are.
Proof that some people are less patient than invertebrates<iframe width="730" height="430" src="https://www.youtube.com/embed/H1yhGClUJ0U" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p> The common cuttlefish is a small cephalopod notable for producing sepia ink and relative intelligence for an invertebrate. Studies have shown them to be capable of remembering important details from previous foraging experiences, and to adjust their foraging strategies in response to changing circumstances. </p><p>In a new study, published in <a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2020.3161" target="_blank" rel="noopener noreferrer">The Proceedings of the Royal Society B</a>, researchers demonstrated that the critters have mental capacities previously thought limited to vertebrates.</p><p>After determining that cuttlefish are willing to eat raw king prawns but prefer a live grass shrimp, the researchers trained them to associate certain symbols on see-through containers with a different level of accessibility. One symbol meant the cuttlefish could get into the box and eat the food inside right away, another meant there would be a delay before it opened, and the last indicated the container could not be opened.</p><p>The cephalopods were then trained to understand that upon entering one container, the food in the other would be removed. This training also introduced them to the idea of varying delay times for the boxes with the second <a href="https://www.sciencealert.com/cuttlefish-can-pass-a-cognitive-test-designed-for-children" target="_blank" rel="noopener noreferrer">symbol</a>. </p><p>Two of the cuttlefish recruited for the study "dropped out," at this point, but the remaining six—named Mica, Pinto, Demi, Franklin, Jebidiah, and Rogelio—all caught on to how things worked pretty quickly.</p><p>It was then that the actual experiment could begin. The cuttlefish were presented with two containers: one that could be opened immediately with a raw king prawn, and one that held a live grass shrimp that would only open after a delay. The subjects could always see both containers and had the ability to go to the immediate access option if they grew tired of waiting for the other. The poor control group was faced with a box that never opened and one they could get into right away.</p><p>In the end, the cuttlefish demonstrated that they would wait anywhere between 50 and 130 seconds for the better treat. This is the same length of time that some primates and birds have shown themselves to be able to wait for.</p><p>Further tests of the subject's cognitive abilities—they were tested to see how long it took them to associate a symbol with a prize and then on how long it took them to catch on when the symbols were switched—showed a relationship between how long a cuttlefish was willing to wait and how quickly it learned the associations. </p>
All of this is interesting, but what use could it possibly have?<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTcxNzY2MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY2MTM0MzYyMH0.lKFLPfutlflkzr_NM6WmnosKM1rU6UEIHWlyzWhYQNM/img.jpg?width=1245&coordinates=0%2C10%2C0%2C88&height=700" id="77c04" width="1245" height="700" data-rm-shortcode-id="7622b8d29429a75e132b03dd6571a09c" data-rm-shortcode-name="rebelmouse-image" />
A diagram showing the experimental set up. On the left is the control condition, on the right is the experimental condition.
Credit: Alexandra K. Schnell et al., 2021<p> As you can probably guess, the ability to delay gratification as part of a plan is not the most common thing in the animal kingdom. While humans, apes, some birds, and dogs can do it, less intelligent animals can't. </p><p>While it is reasonably simple to devise a hypothesis for why social humans, tool-making chimps, or hunting birds are able to delay gratification, the cuttlefish is neither social, a toolmaker, or is it hunting anything particularly <a href="https://gizmodo.com/cuttlefish-are-able-to-wait-for-a-reward-1846392756" target="_blank" rel="noopener noreferrer">intelligent</a>. Why they evolved this capacity is up for debate. </p><p>Lead author Alexandra Schnell of the University of Cambridge discussed their speculations on the evolutionary advantage cuttlefish might get out of this skill with <a href="https://www.eurekalert.org/pub_releases/2021-03/mbl-qc022621.php" target="_blank" rel="noopener noreferrer">Eurekalert:</a> </p><p style="margin-left: 20px;"> "Cuttlefish spend most of their time camouflaging, sitting and waiting, punctuated by brief periods of foraging. They break camouflage when they forage, so they are exposed to every predator in the ocean that wants to eat them. We speculate that delayed gratification may have evolved as a byproduct of this, so the cuttlefish can optimize foraging by waiting to choose better quality food."</p><p>Given the unique evolutionary tree of the cuttlefish, its cognitive abilities are an example of convergent evolution, in which two unrelated animals, in this case primates and cuttlefish, evolve the same trait to solve similar problems. These findings could help shed light on the evolution of the cuttlefish and its relatives. </p><p> It should be noted that this study isn't definitive; at the moment, we can't make a useful comparison between the overall intelligence of the cuttlefish and the other animals that can or cannot pass some variation of the marshmallow test.</p><p>Despite this, the results are quite exciting and will likely influence future research into animal intelligence. If the common cuttlefish can pass the marshmallow test, what else can?</p>
The organisms were anchored to a boulder 900 meters beneath the ice, living a cold, dark existence miles away from the open ocean.
A cold dark place to call home<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTY2MTg1MC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MDU4OTUzN30.1cXnre_xUunoqWMLxjVab5pY_h6kEgSHOfZdFBap838/img.jpg?width=1245&coordinates=237%2C0%2C238%2C0&height=700" id="f349e" width="1245" height="700" data-rm-shortcode-id="ad1d4cb08ae2f8710acf830b13cae854" data-rm-shortcode-name="rebelmouse-image" />
The Antarctic sessile creatures photographed on their home boulder.
Credit: Frontiers in Marine Science<p>Researchers made the discovery while drilling boreholes on the Filchner-Ronne Ice Shelf. <a href="https://nsidc.org/cryosphere/quickfacts/iceshelves.html" target="_blank">Antarctica's ice shelves</a> are giant, permanent floating ice sheets connected to the continent's coastlines, with the Filchner-Ronne shelf being one of the largest. Using a hot-water drill system, they bore through roughly 900 meters of the ice looking for sediment samples. Instead, they discovered a boulder. Two hundred sixty kilometers away from the ice front, the rock was nestled in a world of complete darkness at -2.2°C. And on it, they found sessile organisms.</p><p>"This discovery is one of those fortunate accidents that pushes ideas in a different direction and shows us that Antarctic marine life is incredibly special and amazingly adapted to a frozen world," Dr Huw Griffiths, the study's lead author and a biogeographer of the British Antarctic Survey, said <a href="https://www.eurekalert.org/pub_releases/2021-02/f-sca020921.php" target="_blank">in a press release</a>.</p><p>Sessile creatures are defined by their inability to move freely. They live their lives anchored to a substrate—in this case, the aforementioned boulder. Common sessile animals found in coastal tide pools include mussels, barnacles, and sea anemones, yet none of these were present beneath the Antarctic shelf. Instead, the researchers discovered a stalked sponge, roughly a dozen non-stalked sponges, and 22 unidentifiable stalked organisms.</p><p>Previous boreholes had revealed creatures living in these murky waters, but they had always been free-moving predators and scavengers such as jellyfish and krill. It's not too surprising to find such animals under the ice shelves as their mobility allows them to seek out food that may drift beneath.</p><p>But sessile organisms depend on their food to be delivered to them. That's why they are so bountiful in tide pools; tides and currents are the DoorDash of the ocean world. It's also why the researchers found the sponge's Antarctic lodgings so astounding. Because they live 1,500 kilometers upstream from the nearest source of photosynthesis, it's unknown how a food supply reaches these sponges or whether they generate nutrients from some other means, such as glacial melt or carnivorous noshing.</p><p>"Our discovery raises so many more questions than it answers, such as how did they get there? What are they eating? How long have they been there? How common are these boulders covered in life? Are these the same species as we see outside the ice shelf or are they new species? And what would happen to these communities if the ice shelf collapsed?" Griffiths added.</p><p>To answer those questions, researchers will need to revisit the sponges to collect samples and study them in more depth. We'll also need to explore further the vast reaches of the Antarctic continental shelf. According to the release, counting the previous boreholes, scientists have only studied an area roughly the size of a tennis court to date.</p>
Life will not be contained<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="df51235bca34c1f904d0870f21ed4a19"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/k7ejtzkcl54?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>As science discovers life in more and more unusual places, it's also considering more and more that life has not been contained to our <a href="https://bigthink.com/scotty-hendricks/listen-to-raw-audio-of-carl-sagan-reading-pale-blue-dot" target="_self">pale blue dot</a>. For example, the recent discovery of microbial life in the Atacama Desert has reignited hope that evidence of past life will be found on Mars. <a href="https://mars.nasa.gov/mars2020/mission/overview/" target="_blank">NASA's Perseverance Rover</a> recently land on Mars to begin analyzing soil samples from the Jezero Crater to test that hypothesis.</p><p>Looking to the future, <a href="https://www.nasa.gov/press-release/nasas-dragonfly-will-fly-around-titan-looking-for-origins-signs-of-life" target="_blank">NASA's Dragonfly rotorcraft</a> aims to explore the Saturn moon of Titan. The icy moon has a makeup similar to early Earth's, so the vehicle will study the moon's atmosphere and surface for signs of chemical evidence for life. And the ice-covered surface of Europa could hold twice as much water as Earth and a bevy of hydrothermal activity that could harbor <a href="https://bigthink.com/kevin-dickinson/finding-extraterrestrial-life-in-our-solar-system" target="_self">life within our solar system</a>.</p><p>Here life is, uh, and there it may be.</p>
A new paper explores how noise from human activities pollutes the oceans, and what we can do to fix it.
- The new paper notes three major factors that have changed the ocean soundscape: human activity, climate change, and "massive declines in the abundance of sound-producing animals."
- Noise pollution threatens marine animals because many rely on sound to communicate with each other and sense predators and prey.
- The paper noted several solutions for decreasing human-caused noise pollution, including floating wind turbines and quieter boat propellers.
Duarte et al.<p style="margin-left: 20px;"><em>The illustrations from top to bottom show ocean soundscapes from before the industrial revolution that were largely composed of sounds from geological (geophony) and biological sources (biophony), with minor contributions from human sources (anthrophony), to the present Anthropocene oceans, where anthropogenic noise and reduced biophony owing to the depleted abundance of marine animals and healthy habitats have led to impacts on marine animals<br></em><br>"Ocean soundscapes are rapidly changing because of massive declines in the abundance of sound-producing animals, increases in anthropogenic noise, and altered contributions of geophysical sources, such as sea ice and storms, owing to climate change," the authors wrote. "As a result, the soundscape of the Anthropocene ocean is fundamentally different from that of preindustrial times, with anthropogenic noise negatively impacting marine life."</p><p>Humans pump noise into the ocean in many ways, including sounds from shipping and fishing vessels, sonar devices, oil drilling, construction, acoustic deterrents, warfare and sea-bed mining. Noise pollution can span great distances in some cases. For example, the U.S. Navy's Low Frequency Active Sonar system, used to detect submarines, reaches over 1,505,800 square-miles.</p>
Credit: Pixabay<p>Noise pollution not only stresses marine animals, but also hinders their ability to sense prey and predators, and connect with their family members and groups. For example, species like bluefish tuna rely on sound to communicate with each other, and <a href="https://awionline.org/sites/default/files/uploads/documents/Weilgart_Biodiversity_2008-1238105851-10133.pdf" target="_blank">research has shown</a> that noise from boats disrupts their schooling structure, making it harder for them to migrate to spawning and feeding grounds.<br></p><p>But direct human activity isn't the only thing changing the ocean soundscape. The paper noted that human-caused climate change is "affecting geophony (abiotic, natural sounds)," such as noise caused by waves and melting ice. Taken together, there's clear evidence that noise pollution is disrupting marine life, though "there is lower confidence that anthropogenic noise increases the mortality of marine animals and the settlement of their larvae," the authors wrote.</p>