Tag Archives: octopus

Ancient Fossil Octopus: New Findings Reveal Multiple Species Identified

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Paulsepia mazonensis has captivated the scientific community as a cephalopod species first identified in 2000 from a remarkable 300-million-year-old specimen. This fascinating creature has earned a spot in the Guinness Book of World Records for being the world’s oldest octopus. Recent research has led to its reclassification as a distant relative of the nautilus, offering new insights into the timeline of octopus evolution, according to paleontologists.

Depiction of old cadmus collapse in the Mason Creek Basin, highlighting various Mason Creek fauna, including the polychaete Esconites zelus and the elasmobranch shark Bandringa rayi. Image credit: Franz Anthony.

Originally described from isolated siderite concretions, Paulsepia mazonensis has been recognized as the oldest known octopus, predating earlier estimates by over 150 million years. This revelation raises significant questions regarding our comprehension of cephalopod evolution, according to Dr. Thomas Clements, a paleontologist from the universities of Leicester and Reading.

This intriguing fossil from the Late Carboniferous Maisonkrieg Lagerstätte (311 to 360 million years ago) possesses distinct features, including a ‘sack-like’ fused head and mantle, symmetrical fins, and a pair of eyespots, alongside arms and specialized tentacles, yet lacks evidence for an inner or outer shell.

In a recent comprehensive study, researchers revisited this enigmatic fossil alongside several new specimens.

Employing advanced analytical methods, they uncovered a previously unrecognized radula, the toothed tongue characteristic of most molluscs.

Analysis of the alveolar bone suggests that Paulsepia mazonensis is more aligned with the shelled nautilus than previously thought.

This organism experienced significant decomposition prior to fossilization, leading to its ambiguous classification for decades.

“We conclude that Paulsepia mazonensis is synonymous with the Old Cadmus poli, based on morphological evidence,” the researchers confirmed.

This reinterpretation resolves a longstanding mystery regarding octopus evolution and unveils the oldest preserved nautilus soft tissue ever documented.

Through synchrotron micro-X-ray fluorescence elemental mapping, the team identified dental ossicles concealed within the concrete matrix of Paulsepia mazonensis.

The morphology of radial elements indicates that Paulsepia mazonensis does not correspond to coronal octamers but represents the oldest soft-tissue nautilus fossil discovered to date.

This reclassification challenges the Paleozoic origin of octopuses, further supporting a mid/late Mesozoic origin for crown octopuses while diminishing the credibility of the colloid affinity related to controversial Cambrian soft-bodied fossils like Nectocaris pterix.

The findings accentuate the complexities in interpreting exceptionally preserved soft tissue at the Masonkrieg Lagerstätte and underscore the necessity for thorough reevaluation of enigmatic consolidated soft-bodied fossil materials.

The team’s research paper has been published today in Proceedings of the Royal Society B.

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Thomas Clements et al. 2026. Synchrotron data reveals characteristics of nautiloids Paulsepia mazonensis refuting the Paleozoic origin of octopods. Proc Biol Sci 293 (2068): 20252369; doi: 10.1098/rspb.2025.2369

Source: www.sci.news

Octopus Insights: Rethinking the Evolution of Large Animal Brains

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Common Octopus

Octopuses in shallow waters, such as the common octopus, typically possess larger brains.

Image Credit: Shutterstock

Research suggests that the large brains of octopuses are influenced more by environmental conditions than by social interactions.

It is widely accepted that larger mammalian brains correlate with social behavior, a theory known as the social brain hypothesis. The premise is that the more social connections a species has, the larger their brains must be to handle those interactions. This trend is evident among primates, dolphins, and camelids.

In contrast, cephalopods—like octopuses, cuttlefish, and nautiluses—exhibit significant intelligence despite mostly living solitary lives, with limited parental care and minimal social learning.

To delve deeper into the reasons behind the substantial brain size of these creatures, Michael Muthukrishna and researchers from the London School of Economics analyzed data from 79 cephalopod species with available brain information. They quantified brain size based on the total volume of an animal’s central nervous system, considering that octopuses actually possess nine brains: one central brain and semi-independent brains in each of their eight arms.

“This species is a stark contrast to humans, showcasing unique appendages and behaviors,” Muthukrishna notes.

The findings revealed no direct correlation between brain size and sociability. However, they did uncover that cephalopods generally have larger brains when inhabiting shallow waters, where they encounter a wide array of objects to manipulate and use as tools, along with rich calorie availability. Conversely, species dwelling in featureless deep-sea environments tend to have smaller brains.

“The correlation is quite strong,” Muthukrishna states, “but it’s imperative to approach these findings cautiously,” as only about 10 percent of the existing 800 cephalopod species have brain data accessible.

“The absence of a social brain effect in octopuses is intriguing yet expected,” explains Robin Dunbar from Oxford University, who proposed the social brain hypothesis around three decades ago. He argues that because octopuses do not inhabit cohesive social groups, their brains lack the necessity to manage complex social dynamics.

Professor Paul Katz from the University of Massachusetts articulates the possibility that evolution may have led to smaller brain sizes each time cephalopods adapted to deep-sea environments. “It’s reminiscent of species dimensions reducing on isolated islands; the same could apply to species in the deep ocean,” he mentions.

Muthukrishna’s previous research proposed that brain size not only predicts the extent of social and cultural behaviors but also reflects ecological factors such as prey diversity. Thus, the parallel patterns between cephalopods, having diverged from vertebrates over 500 million years ago, and humans bolster the cultural brain hypothesis. According to Muthukrishna and colleagues, this hypothesis illustrates how ecological pressures and information acquisition lead to the development of larger, more complex brains.

“It’s not solely about social instincts when it comes to large brains,” Muthukrishna asserts.

“I wholeheartedly agree that exploring why humans possess large brains must be informed by our understanding of current species. However, unraveling the evolutionary history of large brains, particularly with cephalopods, is challenging, especially given the radically different predator-prey dynamics when their brains began evolving,” Katz explains.

Additionally, various studies indicate that competitiveness with fish may have spurred cephalopod brain growth, Katz asserts.

Dunbar emphasizes that octopuses may require substantial brainpower for their independent-use of eight arms. “Understanding an octopus’s brain is complex due to its unique structure, but a significant part of its brain’s function is to manage its intricate body mechanics necessary for survival,” he states.

Furthermore, Dunbar notes that it is logical for larger brains to evolve in environments abundant in calories. “You can’t increase brain size without addressing energy consumption. Once you have a more substantial brain, its applications become vast, which is why humans can engage in writing, reading, and complex mathematics—skills not inherently present within our evolutionary contexts.”

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Source: www.newscientist.com

An Octopus Embraces the Fantasy of Rubber Hands, Just Like Us

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Plain-body octopus can be misled into believing false arms are their own

Kawashima and Yuzuku Ishima/Lucys University

Similar to humans, octopuses can be deceived by an illusion that leads them to believe that artificial arms are genuinely theirs.

This phenomenon, known as the rubber hand illusion, was first identified in the late 1990s, wherein a person’s hidden real hand is stroked alongside a fake hand placed before them. This trick was later found to impact other mammals, such as mice.

Recently, Kawashima and Samia, alongside Yuzuru Ikeda at the University of Ryukyu in Okinawa, Japan, discovered that octopuses are likewise susceptible to this illusion.

https://www.youtube.com/watch?v=f8ajppo0qyy

The experiment involved the plains of octopuses (Callistoctopus aspilosomatis) placed in a test tank. Soft gel fake arms, set atop an opaque partition, were placed over one of the octopus’s real arms, obscuring it from view. A researcher then stroked both the actual and fake arms simultaneously with a plastic caliper.


About eight seconds later, the researchers pinched the fake arm with tweezers. All six octopus subjects exhibited defensive behaviors, including color changes, arm retraction, and attempts to escape, across 24 trials.

The illusory effect diminished when the test was conducted without synchronized stroking, used non-synchronized stroking, or when the fake arm’s position didn’t align with the real arm.

During the experiment, the octopus could see false arms resting over a partition that obscured their actual arms

Kawashima and Yuzuku Ishima/Lucys University

According to Ikeda, the experiments reveal both advantages and disadvantages in the neural wiring of both octopuses and humans. “The illusion indicates an octopus’s ability to predict and anticipate, critical for survival,” he states. “Conversely, this capacity arises from neural conflicts and processing errors, suggesting a flaw.”

Kawashima asserts that this investigation will contribute to the understanding of octopus capabilities related to human experiences. “Our results imply that octopuses could serve as a vital model for studying the evolution of body ownership,” she mentions.

Peter Godfrey-Smith at the University of Sydney in Australia found the findings surprising. “This indicates that octopuses possess a complex body image,” he comments. “I was intrigued that the ‘positional mismatch’ scenario indeed worked—showing that the octopus didn’t perceive the rubber arm as its own in that specific situation.”

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Source: www.newscientist.com

Stunningly Intimate Octopus Photos Take Home Aquatic Photography Award

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The mother of the octopus By Kat Zhou

Kat Zhou

This captivating and intimate image offers a unique view of the Caribbean reef octopus (Octopus Briareus), showcasing the mother and her potential offspring in the Blue Heron Bridge diving area near West Palm Beach, Florida.

Following mating, these solitary creatures retreat to seclude themselves while safeguarding their developing eggs. However, for Octopus Briareus and several other octopus species, this tale takes a tragic turn.

Once her mother octopus lays a batch of hundreds of eggs, she ceases to feed and dies shortly after the eggs hatch. Research conducted in 2022 illuminated this phenomenon. The optic nerve gland, the primary neuroendocrine hub of the octopus, regulates lifespan and reproduction in invertebrates, akin to the pituitary gland in vertebrates.

Octopus mothers can dramatically boost cholesterol production post-mating, leading to self-destructive spirals, although the reason behind this cycle remains elusive. One theory suggests that the octopus stops eating for her young.

The mother of the octopus by freelance nature photographer Kat Zhou triumphed in the Aquatic Life category at the Bigpicture Natural World Photography Competition, which invites both professional and amateur photographers to capture, narrate, and advocate for the conservation of Earth’s diverse life forms.

The overall grand prize went to photographer and conservationist Zhou Donglin for Lemur’s Tough Life, a breathtaking capture (shown below) taken at the Tsingy de Bemaraha Strict Nature Reserve in Madagascar. After a challenging trek through rugged terrain, Donglin documented a common brown lemur (Eulemur Fulvus) making a daring leap from one cliff to another—with her baby clinging on.

Lemur’s tough life Zhou Donglin

Zhou Donglin

Next is Mud Skip by Georgina Steytler (shown below), depicting a fascinating reminder of life’s ancient past as a beautiful amphibian emerges from the mud. Steytler, a finalist in the Aquatic Life section of the competition, spent days at Goode Beach in Bloom, Western Australia to capture the precise moment when a Boleophthalmus pectinirostris leaped into the air.

Mud Skip By Georgina Steytler

Georgina Steytler

The final image (shown below) appears reminiscent of a scene from another planet. In reality, Remaining in the Snow by plant photographer Ellen Woods, a finalist in the awards for landscapes, waterscapes, and flora, was captured near her home in Connecticut, in the northeastern USA.

Remaining in the snow By Ellen Woods

Ellen Woods

It features skunk cabbage (Symplocarpus foetidus), often among the first plants to bloom at winter’s end. Notably, it can create its own microclimate, generating warmth of up to 23°C even when ambient temperatures remain below freezing.

This unique capability of thermal regulation protects the plant from frost damage and attracts beetles and fly pollinators drawn to its warmth and scent of carrion.

However, it’s not particularly pleasant; the name arises from its odor, likened to a skunk’s scent when the leaves are disturbed.

The winning photograph will be displayed at the California Academy of Sciences in San Francisco later this year.

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Source: www.newscientist.com

New Deep-Sea Flapjack Octopus Species Found Near Australia

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The Carnarvon Flapjack, known scientifically as opisthoteuthis carnarvonensis, is a newly identified species of octopus. This small, gelatinous octopus measures approximately 4 cm in diameter and features large eyes and vibrant blood-red tentacles.

Carnarvon Flapjack Octopus (opisthoteuthis carnarvonensis). Image credit: TJ Verhoeff, doi: 10.54102/ajt.c46g9.

The Flapjack Octopus belongs to the Opistrotidae family, making it a deep-sea octopod and part of the finned octopod sub-order known for its liver-like characteristics.

Globally, around 50 species are recognized, with 15 of them recorded in Australian waters.

These octopuses have the remarkable ability to flatten their bodies resembling pancakes or flapjacks, hence their common name, or they can appear as small, gelatinous umbrellas.

With disproportionately large eyes, they are well-equipped to spot prey in the dimly lit depths they inhabit.

Their diet mainly consists of worms and small crustaceans, which they catch using their tentacles.

Dr. Tristan Werhev, a systematic taxonomist from the Tasmanian Museum and Art Gallery, stated, “The octopods of the Opistrotidae family are characterized by a distinct combination of external and internal features.”

He further described their anatomy, noting, “The very short dome-like mantle and terminal fins look visually different compared to their proportionately large eyes and thick arms.”

“Internally, they have branched optic nerves and an inner shell reminiscent of leaves (Gradius remnant). These features are shared only with the Cirroctopodidae family, which differs by having relatively large fins, no enlarged male suckers, and unique pallial intubation.”

Opisthoteuthis carnarvonensis is the 10th and latest species described based on specimens collected during the 2022 voyage of the Research Vessel (RV) Investigator.

During the month-long expedition, researchers employed advanced cameras, nets, and sleds to gather samples and capture images from deep-sea environments thousands of meters below the surface.

Five specimens used for the species description were collected from depths ranging between 1,044 and 1,510 m near Carnarvon Canyon and Gascoyne Marine Parks in Western Australia.

Dr. Venetia Joscelyne, a researcher at CSIRO Marine National Facilities, stated, “The 2022 voyage off Western Australia was crucial for enhancing our understanding of the region’s undersea habitats and biodiversity.”

She added, “For the first time, Carnarvon Canyon and Gascoyne Marine Park have been meticulously mapped and explored down to over 5,000 meters.”

“Conducting research in remote offshore or deep-sea environments is typically challenging; the RV Investigator provides researchers with an impressive array of tools for this purpose.”

“During just this single research voyage, we have observed many new species being identified.”

“Incredibly, scientists estimate that more than 1,000 new species remain to be described from specimens collected during RV Investigator voyages over the past decade.”

“These findings are crucial for aiding our understanding of the conservation needs of marine parks and for helping Australia preserve the natural value of its marine environments in the future.”

Dr. Verhoeff noted, “Australia exhibits a higher biodiversity of Dumbo octopus species compared to other nations, with many of these species documented or described in recent years.”

“The Carnarvon Flapjack Octopus is named after the location of its discovery and is solely known from the Carnarvon Canyon and Gascoyne Marine Parks off the coast of northwest Australia.”

“Their presence enhances the ecological significance of these recently established marine parks.”

“Such discoveries have greatly contributed to our knowledge of Australia’s deep-sea ecology and biodiversity.”

“Describing new species is also vital for future ecological research and assessing conservation populations.”

Dr. Lisa Kilkendale, a researcher at the Western Australian Museum, pointed out that a paper detailing the discovery was published this month in Australian Taxonomy.

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TJ Verhoeff. 2025. Flapjack Australia’s Octopod (Cephalopoda: opisthoteuthidae), Part II: Northwest Australia and adjacent seas. Australian Taxonomy 92:1-28; doi:10.54102/ajt.c46g9

Source: www.sci.news

Study Shows Octopus Arm Nervous System is Sectioned into Parts

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Controlling octopus motion is a very complex issue. Each of its eight arms is a muscular hydrostat, a soft-bodied structure without a rigid skeleton that moves with nearly infinite degrees of freedom. Additionally, the arm is packed with hundreds of suction cups, each of which can change shape independently. Despite this complexity, octopuses effectively control behavior along the length of a single arm, across all eight arms, and between suckers. In a new study, scientists at the University of Chicago show that the circuits in the nervous system that control the movements of an octopus' arms are subdivided, allowing this extraordinary creature to explore its environment, grasp objects, and capture prey. discovered that he could precisely control his arms and suction cups.

Octopus at USC Wrigley Marine Science Center on Catalina Island. Image credit: University of Southern California.

“If you're going to create a nervous system that controls dynamic movements like this, that's a good way to set it up,” said Clifton Ragsdale, a professor at the University of Chicago.

“We think this is a feature that evolved specifically in soft-bodied cephalopods with suckers for insect-like movements.”

Each arm of an octopus has an extensive nervous system, with more neurons connected across all eight arms than in the animal's brain.

These neurons are concentrated in large axial nerve cords (ANCs) that snake back and forth as they travel along the arm, forming an extension above each sucker with each bend.

The study authors wanted to analyze the structure of the ANC and its connections with the musculature of the arm. California two-spotted octopus (Octopus bimacroides)a small species native to the Pacific Ocean off the coast of California.

They tried to view a thin circular cross-section of the arm under a microscope, but the sample kept falling off the slide.

They tried peeling the arm lengthwise and got lucky, leading to an unexpected discovery.

Using cell markers and imaging tools to track structures and connections from the ANC, they found that neuronal cell bodies are packed into columns that form corrugated pipe-like segments.

These segments are separated by gaps called septa, through which nerves and blood vessels connect to nearby muscles.

Nerves from multiple segments connect to different regions of the muscle, suggesting that these segments work together to control movement.

“If you think about this from a modeling perspective, the best way to set up a control system for this very long, flexible arm is to break it up into segments,” said Cassady Olson, a graduate student at the University of Chicago. states.

“There has to be some communication between the segments. I can imagine that helping smooth the movement.”

The sucker nerves also exit the ANC through these septa and are systematically connected to the outer edge of each sucker.

This indicates that the nervous system sets up a spatial or topographic map of each sucker.

Octopuses can move their suction cups independently and change their shape.

The suckers are also packed with sensory receptors that allow the octopus to taste and smell things it touches. This is the same as combining your hands, tongue, and nose.

The researchers believe that the suckers (what they called maps) facilitate this complex sensorimotor ability.

To see if this kind of structure is common to other soft-bodied cephalopods, the researchers also Long-tailed squid (Dorytheutis Pileyi)common in the Atlantic Ocean.

These squid have eight arms and two tentacles with octopus-like muscles and suckers.

The tentacles have long stalks without suction cups, and at the end are clubs with suction cups.

While hunting, squid can shoot out tentacles and catch prey with clubs equipped with suckers.

Using the same process to study long strips of squid tentacles, we found that the ANC in the suckerless stem was unsegmented, but the club at the end was segmented in the same way as in the octopus. .

This suggests that the segmented ANC was built specifically to control all types of dexterous sucker-equipped appendages in cephalopods.

However, squid tentacle clubs have fewer segments per sucker, probably because they do not use suckers for sensation like octopuses do.

Squids rely on sight to hunt in the open ocean, while octopuses roam the ocean floor and use their sensitive arms as tools for exploration.

Octopuses and squids diverged more than 270 million years ago, but the similarities in how some of their appendages are controlled by suction cups and the differences in others are a question of how evolution always best resolves them. It shows you how to find a solution.

“An organism with insect-like, sucker-containing appendages needs the right kind of nervous system,” Professor Ragsdale says.

“Different cephalopods have come up with segmented structures, the details of which vary depending on environmental demands and hundreds of millions of years of evolutionary pressure.”

of study Published in a magazine nature communications.

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C.S. Olson others. 2025. Neuronal segmentation in the cephalopod arm. Nat Commune 16, 443;doi: 10.1038/s41467-024-55475-5

Source: www.sci.news

Discovery of four new species of deep-sea octopus in the Pacific Ocean

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Marine biologist at Schmidt Ocean Institute R/V Falco Two expeditions in 2023 exploring seamounts off Costa Rica's Pacific coast discovered at least four new species of deep-sea octopus.

A newly hatched octopus swims away from its egg near a small rocky outcrop informally known as El Dorado Hill. Image credit: Schmidt Ocean Institute.

“The impact is that R/V Falco Research to understand Costa Rica's deep Pacific Ocean will continue into the future and hopefully generate awareness that will lead to policies that protect the country's deep sea,” said Dr. Jorge Cortés, a researcher at the University of Costa Rica.

“We hope this expedition will inspire new generations. Further international cooperation is needed to increase knowledge about our deep-sea heritage.”

During the first expedition in June 2023, Dr. Cortes and colleagues discovered two octopus farms associated with thermal springs.

Six months later, they returned to the nursery and confirmed that they appear to be active year-round.

They also observed several other new species of octopus away from the hot springs.

One of the new species belongs to the genus Octopus Muusocops The octopus is named after the small rocky outcrop, informally known as El Dorado Hills, where it was first discovered.

This is a different species, closely related to, but a different deep-sea octopus farm, found in California's Davidson Seamount in 2018.

Of the four new species in Costa Rica, only the dorado octopus was observed spawning in hot springs.

This discovery is Muusocops This genus evolved to raise its eggs in warm springs on the ocean floor.

“After hard work, our team has discovered a new hydrothermal spring off the coast of Costa Rica, which has become a nursery for deep-sea octopuses and a unique biodiversity site,” said Dr. Beth Orcutt, a researcher at the Bigelow Institute of Marine Science. We confirmed that this is the habitat.”

“It was less than 10 years ago that low-temperature hydrothermal eruptions were detected in ancient volcanoes located far from mid-ocean ridges.”

“These locations are very difficult to find because you can't detect any trace of it in the water column.”

Researchers also discovered a thriving deep-sea skating nursery on the top of another seamount in Costa Rican waters, which they named Skatepark.

They also discovered three hydrothermal springs within the region, located 10 to 30 nautical miles from each other.

These springs all differ from each other in the temperature and chemistry of their fluids, indicating that unique reaction processes drive their formation.

“The Schmidt Ocean Institute supports the global scientific community wherever it is located. Falcor ” said Dr. Jyothika Virmani, Executive Director. Schmidt Ocean Institute.

“Dr. Cortés and Dr. Orcutt have assembled a team that truly embodies international collaboration that empowers Costa Rica's domestic scientists and enriches local knowledge and understanding of the ocean.”

“We look forward to operating off the coasts of Peru and Chile in 2024 and welcoming scientists from South America.”

Source: www.sci.news

Deep-sea Submersible Discovers Four New Species of Octopus

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A female octopus lays her eggs near a small rock outcrop, informally known as El Dorado Hill.

ROV Subastian/Schmidt Ocean Institute

Four new species of deep-sea octopus have been discovered in an underwater mountain range about two miles downstream in the Pacific Ocean off the coast of Costa Rica, according to the Schmidt Institute of Oceanography.

During expeditions in June and December 2023, researchers on the US nonprofit research vessel Falkor also used a remote-controlled vehicle to explore two low-temperature hydrothermal springs, two octopuses, and more. found a nursery, and one skate nursery. Subastian.

Previous research has found areas where octopuses live near low-temperature springs, but these environments have been difficult to find.

Typical 350°C hot hydrothermal vents are easy to spot thanks to smoke rising from the ocean floor. However, the cold spring's water temperature is only about 10 degrees Celsius higher than the average 2 degrees Celsius at the ocean floor, and is only visible through slight diffraction of light.

“It looks like it’s sparkling,” says expedition co-leader. Beth Orcutt at the Bigelow Marine Science Institute, another nonprofit in Maine.

Finding this subtle sign in the dark required multiple dives in different locations. “It's like walking through a forest you've never been in before with a flashlight looking for hot springs,” Orcutt said. “We were kind of making a bet.”

The four new species have not yet been officially described, but one has been named the dorado octopus, after the rock where it was discovered, known as El Dorado Hill.some kind of Muusocopsfemales gather to incubate eggs in warm water.

Orcutt said researchers believe the other species are new based on their appearance. They appear to be solitary, which is common among deep-sea octopuses. “They don't like having their neighbors close,” she says.

These insights into Costa Rica's unique biodiversity could inform regional conservation policy. “It is difficult [protect deep-sea wildlife] That’s when you don’t know it’s underground,” Orcutt says.

Undersea octopus farm

ROV Subastian/Schmidt Ocean Institute

These missions also help inspire and develop local scientific talent through training for early career researchers on how to lead deep-sea explorations, she says. The 310 specimens collected, which also include starfish, spider stars and sea cucumbers, will be kept at the Zoological Museum at the University of Costa Rica, rather than in the United States, where they are not easily accessible to local researchers.

More exploration is needed because the deep sea faces many threats, including mining, Orcutt said. “We're just scratching the surface.”

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Source: www.newscientist.com