from the world's big
Unraveling the mysteries of adult neurogenesis may have clinical applications.
- Neuroscientists don't know the degree to which adult human brains generate new neurons.
- A new study found that adult-born neurons in lab rats continued to grow and mature long after infant-born ones stopped.
- Understanding the process of neuron birth and death can help scientists understand the causes of neurological disorders.
Getting better with age<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzQxODQ1NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNjQxMjkwN30.eGwCMbptF8egRSgm4wyIBlAvjv6x8tqB5pauGurioHc/img.jpg?width=1245&coordinates=0%2C4%2C0%2C5&height=700" id="5b72b" class="rm-shortcode" data-rm-shortcode-id="50b37ca4d09cd4f1db9136b07810874d" data-rm-shortcode-name="rebelmouse-image" />
Reconstructions of adult-born neurons from rats undergoing maturation. Left to right: 2-weeks old, 4-weeks, 6-weeks, and 24-weeks.
Optimize Your Brain: The Science of Smarter Eating | Dr. Drew Ramsey | Big Think<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a5fc406dabd4e2acb818f68be3378bb5"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/J8BnvIku0kw?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6659986/#:~:text=Neurogenesis%20in%20adult%20humans%20remains%20a%20controversial%20area%20of%20research%20among%20neuroscientists.&text=While%20some%20researchers%20report%20that,brains%20persists%20into%20old%20age." target="_blank">The challenge of measuring adult neurogenesis</a> is difficult, but it's not impossible. A big part of the solution is knowing what to measure and where. While this new study was performed on rats—and therefore may be a poor predictor of what we'll see in humans—it can direct future research by showing neuroscientists where to look and what to look for.</p><p>And unlike the hard problem of consciousness, unraveling <a href="https://bigthink.com/mind-brain/neurogenesis-in-adults" target="_self">the mysteries of adult neurogenesis</a> may have clinical applications. Better the lifecycle of neurons may reveal how neurological disorders such as Parkinson's and Alzheimer's disease emerge. There's <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6091047/" target="_blank">even research</a> linking disorders such as depression and anxiety to neurogenesis activity. </p><p>This knowledge may lead to new treatments, but if not, it could also reveal a better understanding of how our lifestyles and environments support brain health and regeneration <a href="https://bigthink.com/mind-brain/super-agers-brain" target="_self">throughout human life</a>.</p>
The importance of finding and shaping learning communities.
- When considering what the future of learning post-COVID-19 will look like, you have to start with a strong foundation. Daniel Kinzer, educator and founder of Pacific Blue Studios, looks at it like a seed that has to be grown.
- Informed by the culture and geology of Hawaii, Kinzer explains the concept of kipuka: a patch of land, untouched by flowing lava, that provides the DNA to restore life to the landscape.
- Applying that idea to the reshaping of education, he says that we must identify those kipuka, find our teachers, and find and shape our own learning tribes that are better suited for what we deem important moving forward.
Scientists are befuddled by where the shark gets most of its food.
- A University of Sydney research team found that the great white shark spends an unexpectedly large amount of time feeding close to the sea bed.
- The group examined the contents in the stomachs of 40 juvenile white sharks and found the remains of a variety of fish species that typically inhabit the sea floor or are buried in the sand.
- The scientists hope that the information gained from this research will assist conservation and management efforts for the species.
Fresh findings<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzM5MjMyNC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYwNjY5NDExM30.3JLqvvn4iB0F29jWuRMnEdmSwY6avTsmo6AP3LgXMxQ/img.jpg?width=1245&coordinates=0%2C333%2C0%2C334&height=700" id="362cb" class="rm-shortcode" data-rm-shortcode-id="f21b84cc3825bf4ac53454c6c4bbb09f" data-rm-shortcode-name="rebelmouse-image" />black shark in blue waterPhoto by Gerald Schömbs on Unsplash<p>A research team from the University of Sydney looked at sharks off the east coast of Australia and found that in their stomachs were remains from a variety of fish species that typically inhabit the sea floor or are buried in the sand. Specifically, the group examined the contents in the stomachs of 40 juvenile white sharks, scientifically known as <em>Carcharodon carcharias</em>, who were caught in the NSW Shark Meshing Program. </p><p>"This indicates the sharks must spend a good portion of their time foraging just above the seabed," explained lead author Richard Grainger, a Ph.D. candidate at the Charles Perkins Centre and School of Life and Environmental Sciences at the University of Sydney, <a href="https://phys.org/news/2020-06-great-white-shark-diet-scientists.html" target="_blank">in a press release</a>. "The stereotype of a shark's dorsal fin above the surface as it hunts is probably not a very accurate picture." </p><p>The study was published on June 8, World Oceans Day, in the journal Frontiers in Marine Science<em>. </em>It's an important step forward for scientists trying to better understand the great white's diet and migratory behavior. </p><p>"We discovered that although mid-water fish, especially eastern Australian salmon, were the predominant prey for juvenile white sharks in NSW, stomach contents highlighted that these sharks also feed at or near the seabed," <a href="https://phys.org/news/2020-06-great-white-shark-diet-scientists.html" target="_blank">said Vic Peddemors</a>, Ph.D., a co-author from the NSW Department of Primary Industries (Fisheries). </p><p>The research team compared this new dietary information with published data on great white feeding habits from other parts of the world where the sharks make home, mostly South Africa. From there they were able to establish a nutritional framework for the species. </p>
What's in a great white's diet?<p><a href="https://www.frontiersin.org/files/Articles/532445/fmars-07-00422-HTML/image_m/fmars-07-00422-t001.jpg" target="_blank">According to the research</a>, the juvenile great white sharks' diets relied primarily on pelagic — mid-water ocean swimming — fish, such as Australian salmon. This made up 32.2 percent of the shark's diet. Bottom-dwelling fish like stargazers, sole or flathead made up 17.4 percent; batoid fish such as stingrays 14.9 percent; and reef fish, like eastern blue gropers, 5 percent.</p><p>The remaining species eaten by the sharks were unidentified fish or less abundant prey. Grainger pointed out that other marine mammals, sharks, and cephalopods — squid and cuttlefish — were eaten at lower rates. </p><p>"The hunting of bigger prey, including other sharks and marine mammals such as dolphins, is not likely to happen until the sharks reach about 2.2 meters in length," <a href="https://phys.org/news/2020-06-great-white-shark-diet-scientists.html" target="_blank">Grainger said</a>.</p><p>Another discovery was that bigger sharks tended to have diets that were higher in fat. Similarly to other animals, this is likely an adaptation to their higher energy needs for migration. Great white's migrate seasonally along Australia's east coast, traveling from southern Queensland to northern Tasmania. The range of distance covered increases with age. </p><p>"This fits with a lot of other research we've done showing that wild animals, including predators, select diets precisely balanced to meet their nutrient needs," said co-author Professor David Raubenheimer, Chair of Nutritional Ecology in the School of Life and Environmental Sciences.</p>
Species conservation and management<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="7bb54774f7a5b923690ad15c2e979aca"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/O2FInaOCqoo?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>Ultimately, the scientists hope that the information gained from this research will assist conservation and management efforts for the sharks, who are considered a vulnerable and declining species due to overfishing and accidental catching in gill nets.</p>Of particular interest to scientists is better management of relations between humans and great whites. According to <a href="https://www.nationalgeographic.com/animals/fish/g/great-white-shark/" target="_blank">National Geographic</a>, of the over 100 annual shark attacks that happen worldwide, a whopping one-third to half can be attributed to great whites. Yet, research has found that the sharks, who tend to have a curious disposition, are often just taking sample nibble before releasing their human prey. So, at least we know humans aren't a great white delicacy.
It looks like a busy hurricane season ahead. Probably.
- Before the hurricane season even started in 2020, Arthur and Bertha had already blown through, and Cristobal may be brewing right now.
- Weather forecasters see signs of a rough season ahead, with just a couple of reasons why maybe not.
- Where's an El Niño when you need one?
Welcome to Hurricane Season 2020. 2020, of course, scoffs at this calendric event much as it has everything else that's normal — meteorologists have already used up the year's A and B storm names before we even got here. And while early storms don't necessarily mean a bruising season ahead, forecasters expect an active season this year. Maybe storms will blow away the murder hornets and 13-year locusts we had planned.
NOAA expects a busy season
According to NOAA's Climate Prediction Center, an agency of the National Weather Service, there's a 60 percent chance that we're embarking upon a season with more storms than normal. There does, however, remain a 30 percent it'll be normal. Better than usual? Unlikely: Just a 10 percent chance.
Where a normal hurricane season has an average of 12 named storms, 6 of which become hurricanes and 3 of which are major hurricanes, the Climate Prediction Center reckons we're on track for 13 to 29 storms, 6 to 10 of which will become hurricanes, and 3 to 6 of these will be category 3, 4, or 5, packing winds of 111 mph or higher.
What has forecasters concerned are two factors in particular.
This year's El Niño ("Little Boy") looks to be more of a La Niña ("Little Girl"). The two conditions are part of what's called the El Niño-Southern Oscillation (ENSO) cycle, which describes temperature fluctuations between the ocean and atmosphere in the east-central Equatorial Pacific. With an El Niño, waters in the Pacific are unusually warm, whereas a La Niña means unusually cool waters. NOAA says that an El Niño can suppress hurricane formation in the Atlantic, and this year that mitigating effect is unlikely to be present.
Second, current conditions in the Atlantic and Caribbean suggest a fertile hurricane environment:
- The ocean there is warmer than usual.
- There's reduced vertical wind shear.
- Atlantic tropical trade winds are weak.
- There have been strong West African monsoons this year.
Here's NOAA's video laying out their forecast:
ArsTechnica spoke to hurricane scientist Phil Klotzbach, who agrees generally with NOAA, saying, "All in all, signs are certainly pointing towards an active season." Still, he notes a couple of signals that contradict that worrying outlook.
First off, Klotzbach notes that the surest sign of a rough hurricane season is when its earliest storms form in the deep tropics south of 25°N and east of the Lesser Antilles. "When you get storm formations here prior to June 1, it's typically a harbinger of an extremely active season." Fortunately, this year's hurricanes Arthur and Bertha, as well as the maybe-imminent Cristobal, formed outside this region. So there's that.
Second, Klotzbach notes that the correlation between early storm activity and a season's number of storms and intensities, is actually slightly negative. So while statistical connections aren't strongly predictive, there's at least some reason to think these early storms may augur an easy season ahead.
Image source: NOAA
Batten down the hatches early
If 2020's taught us anything, it's how to juggle multiple crises at once, and layering an active hurricane season on top of SARS-CoV-2 — not to mention everything else — poses a special challenge. Warns Treasury Secretary Wilbur Ross, "As Americans focus their attention on a safe and healthy reopening of our country, it remains critically important that we also remember to make the necessary preparations for the upcoming hurricane season." If, as many medical experts expect, we're forced back into quarantine by additional coronavirus waves, the oceanic waves slamming against our shores will best be met by storm preparations put in place in a less last-minute fashion than usual.
Ross adds, "Just as in years past, NOAA experts will stay ahead of developing hurricanes and tropical storms and provide the forecasts and warnings we depend on to stay safe."
Let's hope this, at least, can be counted on in this crazy year.
Maybe you've been wondering if you're seeing one persistent squirrel or a rotating cast of characters.
Watching the wildlife outside your window can boost your mental well-being, and it's something lots of people have been doing a lot more of lately.