{"id":30473,"date":"2026-07-31T08:50:00","date_gmt":"2026-07-31T12:50:00","guid":{"rendered":"https:\/\/www.ecoportal.net\/en\/?p=30473"},"modified":"2026-07-31T08:50:00","modified_gmt":"2026-07-31T12:50:00","slug":"24-eyed-cube-bigger-thumbnail-turned","status":"publish","type":"post","link":"https:\/\/www.ecoportal.net\/en\/24-eyed-cube-bigger-thumbnail-turned\/30473\/","title":{"rendered":"A 24 eyed cube no bigger than a thumbnail turned up in a Hong Kong shrimp pond, and its Caribbean relative can learn to dodge obstacles with 4,000 nerve cells and no brain"},"content":{"rendered":"

The water in the shrimp pond looked ordinary, brown and brackish, pressed between mangrove roots at the edge of a busy city, and nobody expected to find anything genuinely new<\/strong> living inside it.<\/p>\n

But when scientists scooped up samples from Mai Po Nature Reserve in Hong Kong, they pulled out something that would force a rethink of learning<\/strong> itself.<\/p>\n

A pond nobody thought to look in<\/h2>\n

Mai Po sits on the northern edge of Hong Kong, a wetland wedged between shrimp farms and the city’s sprawl, and it is well studied, well mapped and well walked by researchers, which is exactly what makes the find so startling.<\/p>\n

Scientists described a new species of the jellyfish genus Tripedalia from an intertidal shrimp pond in the reserve, an animal that had been there all along, hiding in plain sight<\/strong> in water the color of milky tea. It has turned up every year since 2020 during April and May, in water ranging from 68 to 84 degrees Fahrenheit and a salinity that swings between 5.8 and 18 practical salinity units.<\/p>\n

This was a creature discovered not in a deep ocean trench, but in a managed pond<\/strong> beside a megacity.<\/p>\n

Half an inch of perfect geometry<\/h2>\n

Pick this animal up and your first reaction would be confusion, because it looks less like a jellyfish and more like something a mathematician dreamed up. It measures only about six tenths of an inch long, and it belongs to a small group of box jellyfish known for their distinct cube shaped bodies and complex behaviors.<\/p>\n

It carries three pedalia at each of its four corners, each bearing a single tentacle up to about four inches long, and those tentacles are shaped like boat paddles, which lets it swim faster than<\/strong> other jellyfish.<\/p>\n

This new species is the fourth described member of Tripedaliidae and the first record of that family in Chinese coastal waters, so researchers named it Tripedalia maipoensis<\/em> after the place that hid it<\/strong> for so long. The description ran in the journal Zoological Studies on 2 May 2023, with Professor Qiu Jianwen of Hong Kong Baptist University leading the work alongside WWF Hong Kong, Ocean Park Hong Kong and the University of Manchester.<\/p>\n

A visual system unlike anything evolution was supposed to build<\/h2>\n

Here is where the story takes a turn that even biologists find hard to explain. When people picture a jellyfish, they imagine a simple drifting blob with no brain, no bones and no plan, and eyes are one of the last features that come to mind.<\/p>\n

Yet box jellyfish possess one of the most unusual visual systems in the animal kingdom, because each animal has four centers of vision called rhopalia, and each of those contains six eyes, for a total of 24 eyes<\/strong> per animal. Of the six eyes per rhopalium, two have lenses that enable image forming, while the other four sense light and contrast to help the animal find shelter.<\/p>\n

Twenty four eyes doing four separate jobs<\/strong>, in one animal with no brain to process any of it.<\/p>\n

The creature that learns without a brain<\/h2>\n

This is the part that genuinely challenges what we thought we knew. Jellyfish have no centralized brain, so the box jellyfish carries its processing power in the four rhopalia themselves, each of which holds roughly 1,000 neurons, giving the whole animal approximately 4,000 nerve cells in total.<\/p>\n

That is a stark contrast to the roughly 100 billion nerve cells in a human brain, and yet those few thousand cells are doing something remarkable<\/strong>. In an experiment with the Caribbean box jellyfish Tripedalia cystophora<\/em>, researchers showed that box jellyfish learned to spot and avoid obstacles despite having no central brain, associating visual and mechanical stimuli with an obstacle and steering away, with the rhopalial nervous system confirmed as the seat of that learning.<\/p>\n

That feat is called associative learning, and the study<\/a> challenges the notion that such learning requires complex neuronal circuitry, though some researchers note the sample size was small and wider testing is needed. Anders Garm, one of the authors, put it plainly: “It’s surprising how fast these animals learn; it’s about the same pace as advanced animals are doing.” The newly found Hong Kong box jellyfish<\/a> shares this same visual architecture, which means it likely carries the same hidden capacity<\/strong>.<\/p>\n

For another animal bending the rules of intelligence, consider the bee brain<\/a> that passed a rhythm test once thought exclusive to vertebrates, and researchers tracking gray wolves<\/a> along the Alaskan shoreline found a hunting behavior that has never been explained.<\/p>\n

What a shrimp pond just taught us about the nature of seeing<\/h2>\n

The deeper implication reaches far beyond one new species. Rather than building one sophisticated eye capable of doing everything, evolution divided the work among several specialized ones, which is an elegant solution for an animal that lacks anything resembling a conventional brain.<\/p>\n

It means vision, one of life’s most complex gifts, can be built from surprisingly simple parts, and the fact that this species lived in a managed pond beside a busy city also shows that human altered landscapes can still hide unnamed creatures.<\/p>\n

Jellyfish have survived at least 500 million years in Earth’s oceans, and half a billion years of practice is now packed into something smaller than a thumbnail, watching everything with 24 eyes and nothing that looks like a mind.<\/p>\n","protected":false},"excerpt":{"rendered":"

The water in the shrimp pond looked ordinary, brown and brackish, pressed between mangrove roots at the edge of a busy city, and nobody expected to find anything genuinely new living inside it. But when scientists scooped up samples from Mai Po Nature Reserve in Hong Kong, they pulled out something that would force a … Read more<\/a><\/p>\n","protected":false},"author":28,"featured_media":30472,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"rank_math_focus_keyword":"24 eyed cube","rank_math_title":"A 24 eyed cube no bigger than a thumbnail turned up in a Hong Kong shrimp pond, and its Caribbean relative can learn to dodge obstacles with 4,000 nerve cells and no brain","rank_math_description":"A new cube-shaped box jellyfish with 24 eyes was found in a Hong Kong shrimp pond \u2014 and its brainless vision system is rewriting what we know about seeing","footnotes":""},"categories":[83],"tags":[],"class_list":["post-30473","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-earth"],"_links":{"self":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/30473","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/users\/28"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/comments?post=30473"}],"version-history":[{"count":0,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/30473\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media\/30472"}],"wp:attachment":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media?parent=30473"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/categories?post=30473"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/tags?post=30473"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}