Once a week.
Subscribe to our weekly newsletter.
Climate change may bring acidic oceans full of jellyfish
One often-neglected result of climate change is ocean acidification. If this process continues, we may start to see fewer fish and more jellyfish.
- Since the beginning of the industrial era, humanity has been pumping out unprecedented levels of CO2 into the atmosphere.
- A significant portion of this CO2 is sucked back into the ocean, where it reacts with water to produce carbonic acid.
- Most species fair poorly in the newly acidic ocean. Jellyfish, however, seem to resist ocean acidification more than others.
Human beings don't do well when they try to understand things past a certain scale. When you consider the 7.5 billion people on the planet, you don't think of them in the same way as, say, the people who you meet walking your dog or your extended family. People can't conceive of how small the Earth is in comparison with the Sun, and people can't conceive of how broad and ubiquitous climate change really is — which is why some folks scoff at the idea when the Northeast US experiences record snowfall.
Most of us limit our understanding of climate change to the impact that CO2 has on our atmosphere and the resulting warming of the planet. But climate change is a multifaceted phenomenon. As we change our planet's chemistry, all environments experience a subsequent change, not just through the air we breathe but also in the oceans. The oceans of the future won't just be bigger from melting sea ice; they will become acidic seas where the jellyfish reign supreme.
Why the ocean you know and love won’t exist in 50 years
How CO2 turns oceans acidic
CO2 released into the atmosphere traps heat, driving the bulk of climate change's obvious effects. But not all of that CO2 stays in the atmosphere. Since the beginning of the industrial age, the world's oceans have absorbed 525 billion tons of CO2. Today, oceans suck up about 22 million tons per day, roughly a quarter of all the man-made CO2 released into the atmosphere.
In a way, this is helpful. If more CO2 was retained in the atmosphere, the faster the planet would heat up from the greenhouse gas effect. There's no such thing as a free lunch, however. As CO2 mixes with the oceans' H2O, the two molecules combine to form carbonic acid (H2CO3), lowering the oceans' pH and increasing its acidity. Under normal circumstances, natural processes from the dissolved minerals deposited into the oceans by rivers help to keep the oceans' pH levels in balance, but the rate at which oceans are absorbing our CO2 means this process has not been sufficient.
Life under ocean acidification
PHILIPPE LOPEZ/AFP/Getty Images
Nearly all forms of life are extremely sensitive to pH levels. You can imagine how difficult it would be for humanity if all of our air was slightly acidic — such is the case in the oceans. But, like any environmental change, there are losers and winners.
The most obvious loser in this new environment are species that build shells, like oysters, clams, and corals. Any disruption to a food chain puts an ecosystem in danger, but the increased difficulty that corals face when building their shells is particularly worrisome. Corals are a foundation species, meaning that they create and maintain a habitat for other species. Without them, an estimated 4,000 species will be at risk.
While many species of shell-building animals and fish are negatively impacted by ocean acidification, jellyfish don't seem to struggle much at all. One of the ways scientists discovered this was by looking at places in the ocean where CO2 levels are naturally higher, such as nearby volcanic seeps in the Mediterranean. In these locations, jellyfish and other "nuisance" species like dangerous algae exist in much higher numbers than elsewhere. Additional research, too, has demonstrated that as pH levels drop in the ocean, jellyfish numbers rise.
It's unclear how jellyfish will fare as the oceans become even more acidic in the future. So far, it seems they are resistant to acidification, but not immune to it. Some researchers believe that the selectivity of this damage — that ocean acidification seems to affect other species more — is what's leading to the jellyfish's rise. As their competitors and prey becomes less fit, jellyfish capitalize by ramping up their consumption.
As an example, one study looked at how well copepods and jellyfish fared in tanks of normal ocean water and tanks of acidified ocean water. Copepods are small, abundant crustaceans that are critical to ocean ecology, serving as a food source for nearly every species. When box jellyfish were added to the copepod tanks that contained normal ocean water, the jellyfish consumed 37% of the copepods. When added to the acidified tanks, jellyfish ate 83% of the copepods. However, it's not clear whether this occurred because the copepods had been weakened by the acidification, whether the jellyfish became hungrier under the strain of acidification, or some combination of the two.Jellyfish numbers appear to be on the rise, and it looks like ocean acidification is to blame. Unless we learn to curb our CO2 outputs, it may be that our future oceans may become more gelatinous than we'd like.
- Juli Berwald — Our Jellyfish Overlords — Think Again - a Big Think ... ›
- Your home could be lit by jellyfish in the future | World Economic ... ›
A man's skeleton, found facedown with his hands bound, was unearthed near an ancient ceremonial circle during a high speed rail excavation project.
- A skeleton representing a man who was tossed face down into a ditch nearly 2,500 years ago with his hands bound in front of his hips was dug up during an excavation outside of London.
- The discovery was made during a high speed rail project that has been a bonanza for archaeology, as the area is home to more than 60 ancient sites along the planned route.
- An ornate grave of a high status individual from the Roman period and an ancient ceremonial circle were also discovered during the excavations.
Foul play?<p>A skeleton representing a man who was tossed face down into a ditch nearly 2,500 years ago with his hands bound in front of his hips was dug up during a high speed rail excavation.</p><p>The positioning of the remains have led archaeologists to suspect that the man may have been a victim of an ancient murder or execution. Though any bindings have since decomposed, his hands were positioned together and pinned under his pelvis. There was also no sign of a grave or coffin. </p><p>"He seems to have had his hands tied, and he was face-down in the bottom of the ditch," <a href="https://www.livescience.com/iron-age-murder-victim-england.html" target="_blank">said archaeologist Rachel Wood</a>, who led the excavation. "There are not many ways that you end up that way."</p><p>Currently, archaeologists are examining the skeleton to uncover more information about the circumstances of the man's death. Fragments of pottery found in the ditch may offer some clues as to exactly when the man died. </p><p>"If he was struck across the head with a heavy object, you could find a mark of that on the back of the skull," Wood said to <a href="https://www.livescience.com/iron-age-murder-victim-england.html" target="_blank">Live Science</a>. "If he was stabbed, you could find blade marks on the ribs. So we're hoping to find something like that, to tell us how he died."</p>
Other discoveries at Wellwick Farm<p>The grim discovery was made at Wellwick Farm near Wendover. That is about 15 miles north-west of the outskirts of London, where <a href="https://www.hs2.org.uk/building-hs2/hs2-green-corridor/" target="_blank">a tunnel</a> is going to be built as part of a HS2 high-speed rail project due to open between London and several northern cities sometime after 2028. The infrastructure project has been something of a bonanza for archaeology as the area is home to more than 60 ancient sites along the planned route that are now being excavated before construction begins. </p><p>The farm sits less than a mile away from the ancient highway <a href="http://web.stanford.edu/group/texttechnologies/cgi-bin/stanfordnottingham/places/?icknield" target="_blank">Icknield Way</a> that runs along the tops of the Chiltern Hills. The route (now mostly trails) has been used since prehistoric times. Evidence at Wellwick Farm indicates that from the Neolithic to the Medieval eras, humans have occupied the region for more than 4,000 years, making it a rich area for archaeological finds. </p><p>Wood and her colleagues found some evidence of an ancient village occupied from the late Bronze Age (more than 3,000 years ago) until the Roman Empire's invasion of southern England about 2,000 years ago. At the site were the remains of animal pens, pits for disposing food, and a roundhouse — a standard British dwelling during the Bronze Age constructed with a circular plan made of stone or wood topped with a conical thatched roof.</p>
Ceremonial burial site<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzMTk0Ni9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NDgwNTIyMX0.I49n1-j8WVhKjIZS_wVWZissnk3W1583yYXB7qaGtN8/img.jpg?width=1245&coordinates=0%2C82%2C0%2C83&height=700" id="44da7" class="rm-shortcode" data-rm-shortcode-id="46cfc8ca1c64fc404b32014542221275" data-rm-shortcode-name="rebelmouse-image" alt="top down view of coffin" data-width="1245" data-height="700" />
A high status burial in a lead-lined coffin dating back to Roman times.
Photo Credit: HS2<p>While these ancient people moved away from Wellwick Farm before the Romans invaded, a large portion of the area was still used for ritual burials for high-status members of society, Wood told Live Science. The ceremonial burial site included a circular ditch (about 60 feet across) at the center, and was a bit of a distance away from the ditch where the (suspected) murder victim was uncovered. Additionally, archaeologists found an ornately detailed grave near the sacred burial site that dates back to the Roman period, hundreds of years later when the original Bronze Age burial site would have been overgrown.</p><p>The newer grave from the Roman period encapsulated an adult skeleton contained in a lead-lined coffin. It's likely that the outer coffin had been made of wood that rotted away. Since it was clearly an ornate burial, the occupant of the grave was probably a person of high status who could afford such a lavish burial. However, according to Wood, no treasures or tokens had been discovered. </p>
Sacred timber circle<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzMTk0Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY2MDAwOTQ4Mn0.eVJAUcD0uBUkVMFuMOPSgH8EssGkfLf_MjwUv0zGCI8/img.jpg?width=1245&coordinates=0%2C149%2C0%2C149&height=700" id="9de6a" class="rm-shortcode" data-rm-shortcode-id="ee66520d470b26f5c055eaef0b95ec06" data-rm-shortcode-name="rebelmouse-image" alt="An aerial view of the sacred circular monument." data-width="1245" data-height="700" />
An aerial view of the sacred circular monument.
Photo Credit: HS2<p>One of the most compelling archaeological discoveries at Wellwick Farm are the indications of a huge ceremonial circle once circumscribed by timber posts lying south of the Bronze Age burial site. Though the wooden posts have rotted away, signs of the post holes remain. It's thought to date from the Neolithic period to 5,000 years ago, according to Wood.</p><p>This circle would have had a diameter stretching 210 feet across and consisted of two rings of hundreds of posts. There would have been an entry gap to the south-west. Five posts in the very center of the circle aligned with that same gap, which, according to Wood, appeared to have been in the direction of the rising sun on the day of the midwinter solstice. </p><p>Similar Neolithic timber circles have been discovered around Great Britain, such as one near <a href="https://bigthink.com/culture-religion/stonehenge-sarsens" target="_blank">Stonehenge</a> that is considered to date back to around the same time. </p>
Research reveals a new evolutionary feature that separates humans from other primates.
- Researchers find a new feature of human evolution.
- Humans have evolved to use less water per day than other primates.
- The nose is one of the factors that allows humans to be water efficient.
A model of water turnover for humans and chimpanzees who have similar fat free mass and body water pools.
Credit: Current Biology
Being skeptical isn't just about being contrarian. It's about asking the right questions of ourselves and others to gain understanding.
- It's not always easy to tell the difference between objective truth and what we believe to be true. Separating facts from opinions, according to skeptic Michael Shermer, theoretical physicist Lawrence Krauss, and others, requires research, self-reflection, and time.
- Recognizing your own biases and those of others, avoiding echo chambers, actively seeking out opposing voices, and asking smart, testable questions are a few of the ways that skepticism can be a useful tool for learning and growth.
- As Derren Brown points out, being "skeptical of skepticism" can also lead to interesting revelations and teach us new things about ourselves and our psychology.