Tag: Ocean

Flash Recovery Of Ammonoids After Most Massive Extinction Of All Time

The study, conducted by a Franco-Swiss collaboration involving the laboratories Biogéosciences (Université de Bourgogne / CNRS), Paléoenvironnements & Paléobiosphère (Université Claude Bernard / CNRS) and the Universities of Zurich and Lausanne (Switzerland), appears in the August 28 issue of Science.

The history of life on Earth has been punctuated by a number of mass extinctions, brief periods of extreme loss of biodiversity. These extinctions are followed by phases during which surviving species recover and diversify.

The End-Permian extinction, which took place between the Permian (299 – 252.6 MY) and Triassic (252.6 – 201.6 MY), is the greatest mass extinction on record, resulting in the loss of 90% of existing species.

It is associated with intensive volcanic activity in China and Siberia. It marks the boundary between the Paleozoic and Mesozoic Eras.




Until now, studies had shown that the biosphere took between 10 and 30 million years to recover the levels of biodiversity seen before the extinction.

Ammonoids are cephalopod swimmers related the nautilus and squid. They had a shell, and disappeared from the oceans at the same time as the dinosaurs, 65 million years ago, after being a major part of marine fauna for 400 MY.

The Franco-Swiss team of paleontologists has shown that ammonoids needed only one million years after the End-Permian extinction to diversify to the same levels as before.

The cephalopods, which were abundant during the Permian, narrowly missed being eradicated during the extinction: only two or three species survived and a single species seems to have been the basis for the extraordinary diversification of the group after the extinction.

It took researchers seven years to gather new fossils and analyze databases in order to determine the rate of diversification of the ammonoids.

In all, 860 genera from 77 regions around the world were recorded at 25 successive time intervals from the Late Carboniferous to the Late Triassic, a period of over 100 million years.

The discovery of this explosive growth over a million years takes a heated debate in a new direction.

Indeed, it suggests that earlier estimates for the End-Permian extinction were based on truncated data and imprecise or incorrect dating.

Furthermore, the duration for estimated recovery after other lesser extinctions all vary between 5 and 15 million years.

The result obtained here suggests that these estimates should probably be revised downwards.

The biosphere is most likely headed towards a sixth mass extinction, and this discovery reminds us that the recovery of existing species after an extinction is a very long process, taking several tens of thousands of human generations at the very least.

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Pass it on: Popular Science

5 Reasons Why Octopuses Are the Weirdest

No matter how well they camouflage, octopuses will always stand out for a variety of crazy reasons — at least to those of us who live above the water line.

Octopuses are really good at blending in. They match their skin color and texture to whatever’s around them until it looks as if they’ve disappeared.

But no matter how hard they try, there are other reasons octopuses still stand out — at least to those of us who live above the water line. Here are a few ways octopuses set themselves apart:

1. They see with their skin.

No, they don’t have a million eyeballs. But scientists at the University of California in Santa Barbara discovered that octopus skin contains the same proteins that are found in eyes.

Just like the pupils of your eyes expand and contract with light, so do the muscles around an octopus’s chromatophores, which are the cells that allow it to change color.

They probably don’t pick up detail very well through their skin, but they definitely see the light!

2. They shape-shift.

Some octopuses are masters of the fake-out. The appropriately named mimic octopus would totally win Halloween with its ability to make itself look like something it’s not.




3. They have three hearts and nine brains.

Two of the hearts pump blood to the gills, and the third pumps blood to the organs in the rest of the octopus. According to Smithsonian, the third heart stops beating while the octopus is swimming.

4. They’re cannibals.

At least the giant Pacific octopus is. Found in the northern Pacific Ocean, adults often weigh more than 50 pounds.

They prefer to live alone until it’s time to mate, which is probably for the best, since they eat almost anything they can get their eight arms on — from small sharks to each other.

5. They manipulate their own RNA.

Scientists may have just discovered how an invertebrate got so smart. It turns out that octopuses can edit their own RNA.

Think about it like this: If you’re building a house, you’re going to get an architect to draw up a blueprint. That blueprint is your DNA.

To build the house, you’re going to have to hire a general contractor to execute what’s on the blueprints.

In humans, the general contractor mostly does what the blueprint says. He knows that putting in a deck when you wanted a pool could end up costing him a lot.

But for some reason, the octopus’s general contractor changes the plan in the heat of the moment. Literally. Scientists have known for a while that octopuses use RNA editing to function in the cold.

But with new information on the extent to which they pull this off, researchers now wonder if this ability will translate to a survival strategy as the oceans warm and acidify.

If humans want to make changes like this, we have to go back to the blueprints. We rely on DNA mutations passed to the next generation.

So what’s the cost to the octopus for the decisions of a headstrong contractor? Its blueprint hasn’t changed much in the last hundred million years.

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180 Million-Year-Old Crocodile Had Dolphin-Like Features, Tells Tale Of ‘Missing Link’

The discovery of an ancient type of crocodile that lived during the Jurassic Period, at the height of the age of dinosaurs, has shed new light on the species.

The 180 million-year-old fossil, named Magyarosuchus fitosi, shows that some ancient crocodiles evolved to have dolphin-like features.

The fossil was analyzed recently and found to have abnormal vertebra in its tail fin, effectively combining two different families of crocodiles – one that had limbs for walking on the surface and a bone-like protective armor on its back and one that had tail fins and flippers to aid with swimming in the ancient seas.




This fossil provides a unique insight into how crocodiles began evolving into dolphin and killer whale-like forms more than 180 million years ago,” Dr. Mark Young, of the University of Edinburgh’s School of GeoSciences, said in a statement.

The presence of both bony armour and a tail fin highlights the remarkable diversity of Jurassic-era crocodiles.

The new finding was made after the team of paleontologists analyzed the bones, which had been kept at a museum in Budapest. The fossil was originally discovered in Hungary in the Gerecse Mountains.

With an estimated body length of 4.67–4.83 m [15 feet – 16 feet] M. fitosi is the largest known non-metriorhynchid metriorhynchoid,” the study’s abstract reads.

The abstract continues: “The combination of retaining heavy dorsal and ventral armors and having a slight hypocercal tail is unique, further highlighting the mosaic manner of marine adaptations in Metriorhynchoidea.”

In addition, the newly-discovered species had large, pointed teeth, used to grasp prey, the statement added.

The study was published on May 10, in PeerJ, a peer-reviewed scientific journal.

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Meet The Snot-Dwelling Sea Creatures Who Help Move Food Through The Ocean

Hundreds of feet below the ocean’s surface, animals smaller than the palm of your hand make their houses out of snot.

These bizarro creatures called larvaceans keep the oceans teeming with life by gobbling up anything nutritious that’s floated down from the surface.

These little guys, which are shaped like tadpoles, filter a truly shocking amount of water in a single hour — between two and four of those giant five-gallon water jugs that get delivered to your office, according to a study in the journal Science Advances.




Giant larvaceans could push all of the water around them in Monterey Bay through their filters within 500 days; if a lot of them were all together and working as hard as they could, they could filter that same volume of water in just 13 days.

In order to find out exactly how these mysterious mucus-dwellers work, scientists at the Monterey Bay Aquarium Research Institute outfitted a remote-controlled vehicle with an arm wielding a laser to light up the food particles, and trained it on the giant larvaceans as they pumped water through their mucus and into their mouths.

A video camera on the vehicle recorded the flow, and the scientists published their findings today in the journal Science Advances.

The nutrients that don’t go toward keeping these creatures alive and in luxurious mucus homes get pooped onto the seafloor. And if the snot houses get too clogged up, the larvaceans simply drop them.

There, the poop and old mucus-shrouds feed bottom-dwelling sea creatures. It’s like a giant, oceanic, digestive system where nothing gets wasted — and where food gets grosser as it travels downward.

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5 Hard-Shelled Facts About Horseshoe Crabs

The plodding sea creatures have weird blood, weirder swimming habits, and a secret weapon that’s probably saved your life.

1. HORSESHOE CRABS ARE INCREDIBLY OLD.

Discovered in 2008, the 25 millimeter-wide Lunataspis aurora crawled over Manitoba 445 million years ago. This makes it the world’s oldest-known horseshoe crab.

Four species are with us today, all of which closely resemble their long-extinct ancestors.

Supposedly frozen in time, horseshoe crabs are often hailed as “living fossils” by the media.




Yet, appearances can be misleading. Evolution didn’t really leave these invertebrates behind. They’ve transformed quite a bit over the past half-billion years.

For instance, some prehistoric species had limbs that split out into two branches, but today’s specimens have only one.

2. THEY’RE NOT CRABS.

In fact, they aren’t even crustaceans. Unlike real crabs and their kin, horseshoe “crabs” lack antennae.

So, where do the strange ocean-dwellers belong on the arthropod family tree? Biologists classify them as chelicerates, a subphylum that also includes arachnids.

Members possess two main body segments and a pair of unique, pincer-like feeding appendages called chelicerae.

3. EACH ONE HAS A HUGE ARRAY OF SIGHT ORGANS.

Large compound eyes rest on the sides of their shells. Come mating season, these bean-shaped units help amorous crabs locate a partner. Behind each one, there’s a small, primitive photoreceptor called a lateral eye.

Towards the front of the shell are two tiny median eyes and a single endoparietal eye. On its underside, a horseshoe has two “ventral eyes,” which presumably help it navigate while swimming.

4. BABIES CAN SWIM UPSIDE DOWN.

Walking around on the ocean floor is generally how horseshoe crabs get from point A to point B.

Nevertheless, young ones will often flip over and start propelling themselves through the water, using their gills as extra paddles. With age, they do this less frequently.

5. THE SPIKED TAIL HAS SEVERAL USES.

Stinging isn’t one of them, despite what many falsely believe. Among its uses are assuming rudder duties and helping the arthropod right itself after getting stuck on its back.

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Is There Still Time To Save The Great Barrier Reef?

New research published today in the scientific journal Global Change Biology shows that adopting best management practices can help the Great Barrier Reef in a time of climate change.

The study models a range of predicted outcomes for the Reef out to 2050 under different scenarios of future climate change and local management action.

There is significant potential for coral recovery in the coming decades,” said Dr Nick Wolff, Climate Change Scientist at The Nature Conservancy.

But under a scenario of unmitigated greenhouse gas emissions and business-as-usual management of local threats, we predict that after this recovery, average coral cover on the Reef is likely to rapidly decline by 2050.”




The research involved scientists from The Nature Conservancy; The University of Queensland; James Cook University; the UK’s Centre for Environment, Fisheries and Aquaculture; and the Australian Institute of Marine Science (AIMS).

It modelled changes to corals that make up the Great Barrier Reef in the presence of a range of threats including cyclones, Crown-of-Thorns Starfish, nutrient runoff from rivers and warming events that drive mass coral bleaching.

The study provides much-needed clarity around how conventional management actions can support the resilience of the world’s largest coral reef ecosystem.

The $60M package announced recently by the Federal Government including $10.4M for Crown-of-Thorns Starfish control and $36.6M for measures to reduce river pollution is a positive step.

This could buy us some critical time,” said Dr Wolff.

The Queensland and Federal Governments have the right strategy in pursuing ambitious targets for water pollution reduction by 2025.

Further large-scale investments from both the private and public sectors should now be mobilised to expand and accelerate a range of innovative and tailored solutions to ensure targets are met.

Importantly though, the positive signs for the future shown in the research also depend strongly on whether the world meets the ambitious carbon emission targets of the Paris Climate Agreement.

The study shows that in a world of unmitigated carbon emissions, the increased frequency and severity of coral bleaching events will overwhelm the capacity of corals to recover and the benefits of good management practices could then be lost.

The study’s results also come with an important warning: not all coral reefs can be protected by good management under climate change, even if global warming can be kept below 1.5°C.

To protect the most climate sensitive species in the hardest-hit places, we would need to consider additional and unconventional management interventions beyond carbon mitigation AND intensified management.

“A new innovative R&D program to develop such interventions, including ways to boost the spread of warm-adapted corals to naturally cooler parts of the Great Barrier Reef, is included in the Australian Government’s recent $60M announcement. It’s a big step in the right direction,” concluded Dr Anthony.

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How Much Water Pressure Can The Human Body Take?

Depending on how you look at it, the human body is either one of the most vulnerable things on the planet, or one of the most resilient.

It’s true we can do amazing things — heal where we once were bleeding, attack and destroy unfriendly microbial invaders, even knit our own bones back together.

But despite our many abilities, we’re still pretty delicate when you consider the universe around us.

There’s only a tiny window of conditions in which we can thrive, and things that are rather inconsequential in the universe — a dip in oxygen, shocking cold, a flare of nuclear radiation — would mean the end of us in the blink of an eye.

But what exactly can we take? What are the limits of our survival, and what happens to our body if we cross them?

Here we explore the body’s (many) breaking points. First up: water pressure.




What is pressure?

Pressure can generally be defined as the force, per unit area, applied to the surface of something. We’re always under a certain amount of pressure, we just don’t notice.

We hear about air pressure on the weather channel, but we actually have our own pressure in air-filled spaces of our body like our lungs, stomach, and ears.

Our internal pressure is usually equal to the outside air pressure (the weight of the atmosphere pushing down on us.)

We become uncomfortable whenever we venture away from sea level; our internal pressure is no longer equal to the ambient pressure. This is why our ears hurt when we go up in a plane or when we dive too deep underwater.

Underwater Pressure

Ever wonder why we can’t just create extra-long snorkels to breathe underwater? Seems like an obvious and easy solution for breathing without an oxygen tank, but there’s a good reason this can’t work.

For every 33 feet a diver descends the weight of the water above them increases by 15 pounds per square inch.

At only a few feet below the surface, the water pressure is already too great for the muscles that expand and contract our lungs to work, making it extremely difficult for us to draw breath.

A couple feet of water pressure isn’t enough to do serious damage yet, but looking at deeper levels shows how pressure affects us a little more gradually.

At a depth of around 100 feet, the spongy tissue of the lung begins to contract, which would leave you with only a small supply of air that was inhaled at the surface.

An ancient “dive-response” is then triggered in our body, which constricts the limbs and pushes blood toward the needier heart and brain.

If you somehow got stuck in the middle of an oceanic abyss, the deepest part of the ocean, you’d have a few things to worry about.

The lack of breathable oxygen, freezing cold, and these charming creatures, to name a few, but the huge amount of water pressure pressing down on you would definitely be the immediate threat.

Since your body’s internal pressure is so much less than the ambient pressure, your lungs would not have the strength to push back against the water pressure.

At a deep enough level, the lungs would collapse completely, killing you instantly.

This is the most extreme consequence of underwater pressure, but thankfully most of us will never have to deal with ocean depths of this magnitude.

So, how deep can we go? Scientists haven’t yet determined a hard limit for how deep we can survive underwater.

There have been a few instances of divers surviving ridiculous depths (not without side effects), but most professional free divers don’t go past 400 feet deep.

The only way to test a limit would be to test on a real, live human, so obviously there are no handy studies to help us formulate an answer.

Scientists do know, however, what would happen to a diver who crossed their body’s limit. A diver could die from bleeding into the lungs, or pass out from the strain the redistribution of blood lays on the heart.

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Sea Level Rise in the San Francisco Bay Area Just Got a Lot More Dire

If you move to the San Francisco Bay Area, prepare to pay some of the most exorbitant home prices on the planet. Also, prepare for the fact that someday, your new home could be underwater—and not just financially.

Sea level rise threatens to wipe out swaths of the Bay’s densely populated coastlines, and a new study out today in Science Advances paints an even more dire scenario: The coastal land is also sinking, making a rising sea that much more precarious.

Considering sea level rise alone, models show that, on the low end, 20 square miles could be inundated by 2100. But factor in subsiding land and that estimate jumps to almost 50 square miles. The high end? 165 square miles lost.

The problem is a geological phenomenon called subsidence. Different kinds of land sink at different rates.

Take, for instance, Treasure Island, which resides between San Francisco and Oakland. It’s an artificial island made of landfill, and it’s sinking fast, at a rate of a third of an inch a year.




San Francisco Airport is also sinking fast and could see half its runways and taxiways underwater by 2100, according to the new analysis.

Now, subsidence is nothing new to climate scientists. “People have been aware that this is an issue,” says UC Berkeley’s Roland Burgmann, coauthor of the paper.

What was missing was really data that has high enough resolution and accuracy to fully integrate” subsidence in the Bay Area.

To get that data, the researchers took precise measurements of the landscape from lidar-equipped aircraft.

They combined this with data from satellites, which fire radar signals at the ground and analyze the return signals to estimate how fast land is moving either toward the spacecraft or away from them.

By comparing data from 2007 to 2011, the team showed that most of the Bay’s coastline is subsiding at a rate of less than 2 millimeters a year.

Which may not seem like much, but those millimeters add up, especially considering a study that came out last month suggested sea level rise is accelerating.

The developing world is nowhere near ready to deal with subsidence and rising seas, but neither is the developed world.

This is a problem that defies human ingenuity. It’s not like the San Francisco Bay Area can build one giant sea wall to insulate itself.

And it’s not like low-lying Florida can hike itself up, or New York City can move itself inland a few hundred miles.

Save for keeping seas from rising in the first place.

That, of course, would require a tremendous global effort to cut back emissions. But even conservative projections suggest future sea level rise could be dramatic.

Which means we as a species have to seriously reconsider the idea of a coastal town, or in case of the Bay Area, a sprawling coastal metropolis. Because the sea is coming to swallow us, and there’s nothing we can do to stop it.

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Pass it on: New Scientist

Sea Urchins Can Scrape Their Way Through Solid Rock To Make Themselves Homes

The sea urchin is well known for its many outward-pointing spines. However, five symmetric teeth at the center of its body are even more impressive than the spines.

These teeth are able to chew through solid rock, making a cavity in which the sea urchin hides and withstands the surge of water currents.

Scientists have long wondered how sea urchin teeth can withstand grinding and scraping against rock surfaces. After all, the teeth are made of calcite (CaCO3) which is just average in mineral hardness.

Close study reveals some of the sea urchin’s secrets of success. The calcite of its teeth is in the form of a cemented mosaic of plates and fibers.




This composite structure greatly increases tooth durability. Between the calcite plates is a weaker organic material which functions as the ‘weak link’.

It is at these plate boundaries where the tooth eventually breaks, similar to perforations on a roll of paper towels.

The tooth continues to grow at a rate which just compensates for the loss due to surface breakage. In addition, the fracture occurs in an angular way which keeps the edge of the tooth sharp for cutting into rock.

Measurement on one type of sea urchin found tooth growth at 0.006 inches per day, or about 0.2 inches per month.

Close up look of Sea Urchin’s teeth.

The renewable urchin teeth suggest application in industry: Self-sharpening blades for tools.

On the scale of everyday tools, an analogy could consist of a slow-moving metal rod with a variable composition. On the scale of nanotechnology, cutting tools may be possible which continually grow and sharpen themselves.

Sea urchins are said to have evolved their rock-boring ability over 200 million years of evolutionary history.

However, their fossils appear fully modern and functional, similar to living urchins. In truth, similar to all living creatures, sea urchins were part of supernatural biblical creation which occurred just thousands of years ago, not millions or billions of years.

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Rare Deep-Sea Creatures May Use Underwater Chimneys To Keep Their Eggs Warm

Nearly two centuries ago, among the crystalline waters and jagged volcanic outcrops of the Galapagos Islands, a young British naturalist noticed something special: Each inhabitant of these islands was so perfectly adapted to its landscape that one could tell where an animal came from just by glancing at it.

Marveling at the diversity of the area’s finches, he wrote in his diary, “one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.”

It was the kernel of the idea that would turn Charles Darwin into one of the most famous names in biology and “On the Origin of Species” into one of the most influential texts of all time.

From a simple single-cell organism sitting in a primordial soup, life has adapted, diversified, evolved and endured.

But little did Darwin know that an even more impressive testament to life’s stunning versatility was unfolding 30 miles out to sea and 5,500 feet below the waves.




There in the utter darkness and crushing pressures of the deep ocean, a rare stingray-like creature called a Pacific white skate today lays its eggs among the hot plumes that gush from hydrothermal vents.

This seems daring — the underwater equivalent of a bird building its nest at the mouth of a volcano — but it may be a stunningly sophisticated maneuver, scientists say.

Eggs incubate faster when they’re warm, increasing the likelihood that the offspring will survive to perpetuate their parents’ DNA.

I think it’s phenomenal,” said Dave Ebert, program director of the Pacific Shark Research Center at Moss Landing Marine Labs in California and co-author of a new study about the discovery.

As far as he is aware, it is the first time any marine animal has been seen exploiting the hydrothermal vent environment for this purpose.

This is a very complex behavior pattern,” Ebert said, “and it gets into why there are so many different species” of skate.

Skates, sometimes called “flat sharks,” are a diverse family within the class of fish called Elasmobranchs, which also includes sharks and rays. Like their cousins, skates are ancient, boneless and predatory.

Their kite-shaped bodies have been seen soaring over the bottoms of every ocean in the world.

The Pacific white skate is the deepest-dwelling species in this group. Ranging between half a mile to nearly two miles below the surface, they are an enigma to scientists — beyond the reach of all but the sturdiest submersibles.

Almost nothing is known about them,” said Pelayo Salinas de Léon, a marine biologist at the Charles Darwin Foundation. Only half a dozen specimen have ever been studied in a lab.

On a warm June morning, the researchers dropped their remote-operated underwater vehicle, or ROV, into the azure waters of the Pacific.

For 90 minutes it sank deeper and deeper, the ocean around it darkening to cobalt, then navy, then black. A long fiber-optic cable tethered the craft to the ship where scientists watched a live feed of the descent.

No sooner had the ROV reached the sea floor than they spotted a cluster of rectangular pouches clustered near the base of one of the black-smoker chimneys.

It was instant jackpot,” Salinas recalled.

The egg cases were about the size of iPhones and the color of banana peels, with tails at the corners that give them their common name — “mermaid’s purse.”

More than half were spotted within 65 feet of a chimney, and nearly 90 percent were in places where the water temperature was higher than its average of 37 degrees Fahrenheit.

The researchers’ report of their discovery was published Thursday in the journal Scientific Reports.

They continue to work on their analysis of the biodiversity survey at Iguanas-Pinguinos, with Salinas estimating that they identified about 30 new species.

There probably are hundreds, if not thousands more, to be found. The ocean floor is the largest habitat on Earth, but the surfaces of the moon and Mars are better known.

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