Lab Notes

Aging is, at least for now, inevitable, and our eyes are not immune to those changes. Vision loss is, in fact, one of the top 10 causes of disability in the US. A new study, however, shows that this might be reversible in the future. 

A large team of geneticists, ophthalmologists, and other scientists used a group of molecules called Yamanaka factors to turn cells in the eyes of mature mice back to a youthful state. This reversed the damage done by aging, and the cells were then able to regenerate, connect back to the brain, and vision was restored in both models of normal aging and glaucoma.

Yamanaka factors are nothing new in neuroscience. They are named after the 2012 Nobel Prize for Medicine after Shinya Yamanaka led research using those factors to convert mature adult cells back to stem cells, kickstarting the field of induced pluripotent stem cells — cells reprogrammed with the ability to generate other types of cells. 

Normal aging makes cells more prone to damage through chemical alterations to DNA modifications called epigenetic changes. By using a subset of the Yamanaka factors, researchers reversed epigenetic changes. 

Although this is a study completely done in mice, there is hope that similar treatments could be used in humans to restore vision. Lastly, one of the most exciting aspects of the use of these factors to regenerate retinal ganglion cells (eye cells), is that they are by definition neurons, meaning that this study can potentially be translatable to other areas of the nervous system.

Plants are not the only organisms that photosynthesize using chloroplasts. Elysia, a genus of sea slugs, are notorious for stealing chloroplasts from green algae and using photosynthesis to feed themselves. These “solar-powered sea slugs” have been objects of intrigue since the late 1800s. 

Scientists have worked out a lot about how and why these sea slugs steal chloroplasts (rightfully called kleptoplasts in this context). Kleptoplasts — from the Greek kleptes, meaning thief — help slugs tide over difficult times when algae might not be readily available, letting them generate their own energy from light. One question that has been keeping scientists awake at night, though, is how the slugs manage to keep these kleptoplasts functional in their own bodies for up to months on end.

Algal chloroplasts are not designed to work efficiently in slug bodies. Within algae, chloroplasts are protected from light-induced damage by several mechanisms, but these processes seem to be absent in slugs. So what are the slugs doing to protect their stolen goods from damage? A new study published in the journal eLife has some answers.

By comparing how algal chloroplasts and slug kleptoplasts function under different light and oxygen conditions, the researchers found that the slugs have devised their own strategies to keep the kleptoplasts safe. The slugs essentially tweak the chemistry of certain kleptoplast components to reduce the formation of harmful molecules called reactive oxygen species. When exposed to light, the slugs also convert any extra energy to heat, again protecting the kleptoplasts from light-induced damage. 

Although the scientists are still working to find the molecules that help Elysia use their kleptoplasts more efficiently, this study helps us understand how these animals evolved their selective thievery. In the long run, the researchers hope to figure out how chloroplasts came to be in the first place, as they are thought to have originated from endosymbiotic cyanobacteria.

Human activity can change how and what predators eat. Niche partitioning – the way that animals divvy up resources like food and habitat spaces – allows different predator species to coexist while avoiding conflict. But as humans expand into new environments, these carefully balanced scales can tip and force animals into competing with each other instead of living in harmony. 

Researchers from the University of Wisconsin-Madison investigated how human activity impacted the feeding behaviors of predators within the Great Lakes region of the United States. They examined the diets of seven species (wolves, coyotes, bobcats, red foxes, gray foxes, fishers, and American martens) living in areas impacted by varying levels of human disturbances, ranging from protected areas to urban landscapes.

They discovered that human activity caused predators to alter their diets and feeding behaviors. As human activity increased, the predators' diets more frequently overlapped. They also ate crops and preyed on domestic animals more often.

Predators reacted to human activity differently depending on their dietary preferences: Flexible species with generalist diets, like foxes and coyotes, took advantage of readily available crops and domestic animals. Specialized species with restricted diets, like bobcats, were unable to alter their behavior, so their diets more frequently overlapped with other predators. Small predators (like martens) completely shifted their diets to avoid competition with larger species. 

Human disturbances that simultaneously change food and habitat availability force species to compete over limited resources. As animals incorporate humans' food resources into their diets, they increase the likelihood of human-wildlife conflicts. The researchers warn that by altering predator behaviors, human activities could unhinge the established order and function of entire ecosystems.

Extinction is a natural process. Our world has experienced different waves of mass extinctions, the most widely known being the extinction of the dinosaurs. But now, due to extensive human activity and destruction, species are rapidly blinking out of existence, and extinction rates have increased to about 1000 times their expected amount. 

But conservation biologists around the world have dedicated their lives to keeping as many species as possible on the planet. In a recent study published in Conservation Letters, a group of these scientists joined forces to assess if their work was paying off. 

They focused on 73 species, 48 birds and 25 mammals, which were well documented by the International Union for Conservation of Nature and Natural Resources (IUCN), and estimated the probabilities that these species would have disappeared forever without any conservation actions. 

They calculated that between 21 and 32 bird species and 7 to 16 mammal species had been saved from extinction from 1993 to the present — with nine to 18 bird species and two to seven mammal species saved over the past decade. Since 1993, 10 bird and five mammal species are known to have gone extinct, so the researchers estimated that without conservation intervention the extinction rate for birds and mammals would have been up to 4.2 times higher since 1993, and 12 to 26 times higher since 2010. 

Contrary to many conservation stories these days, the message of this study was clear and optimistic: conservation actions are working. With more focused efforts between governments, NGOs, zoos/aquaria, and other stakeholders, we can save even more species from extinction in the future. 

By late March 2020, nearly every state in the US had adopted some form of social distancing measures in order to slow the spread of COVID-19. Almost overnight, with schools and business closed, many people were left with nothing to do but stay home. As a result, cities witnessed a sharp decrease in car traffic. The air quality in these cities seemed to rapidly improve.

But how big of an impact did the coronavirus pandemic have on our air pollution? A new study published in the Bulletin of Atmospheric Science and Technology has quantified exactly that.

Using publicly-available data, they compared the measurements of nitrogen dioxide and PM_2.5 (fine particulate matter) measurements from April 2020 to data from 2015-2019. Nitrogen dioxide, which is emitted from exhaust produced by motor vehicles, is a good proxy for car traffic. PM_2.5 is particulate matter less than 2.5 micrometers in diameter, thinner than human hair. Its small size allows it to travel deep into your lungs and it causes many negative health effects. PM_2.5 is also emitted by vehicles, but its levels are more connected to commercial diesel trucks than passenger cars.

The researchers found that nitrogen dioxide levels decreased during the COVID-19 lockdowns, corresponding to the decreased car travel. However, in contrast to nitrogen dioxide, concentrations of PM_2.5 didn’t seem to be correlated with the decrease in human travel, and were actually more likely to be higher than the daily averages from the previous five years.

The researchers attribute this partly to the fact that commercial trucks didn’t experience the same decline in usage as passenger cars. Similarly, the other common emission sources of PM_2.5, such as power plants and residential heating, also didn’t experience a decline, and may also factor into these findings. 

The mucus lining our intestines is decorated with sugars, which are an important food source for bacteria living in the gut. However, friendly gut microbes aren’t the only ones who devour mucus-derived sweets. The diarrhea-inducing bacterium, Clostridioides difficile (C.diff), also consumes sugars to survive in the gut. 

Normally, resident gut bacteria resist C. diff infection (CDI) by hogging nutrients this nasty bug needs to live. Antibiotic treatment is a major risk factor for CDI, as it depletes the populations of these resident gut bacteria. While it is known that restoring beneficial members of the gut bacterial community can help fight CDI, the use of microbes that specifically inhibit C. diff mucus consumption is an area of untapped therapeutic potential. 

However, a recent study published in Nature Communications suggests such therapies might be worth pursuing.

Researchers incubated mouse poop with various mucosal sugars suspended in “heavy water”, a form of H₂O in which hydrogen is replaced by its heftier sibling, deuterium. This allowed researchers to track which bacteria were eating the sugars in the mouse poop by looking at which contained deuterium and which did not. Five bacteria that specifically consumed C. diff-preferred mucosal sugars were combined to create a consortium of bacteria that could prevent C. diff from accessing its food. The researchers called this group, "BacMix." 

They found that when C. diff was incubated with its preferred food sugars in the presence of BacMix, it grew worse than if incubated alone. The researchers treated mice with BacMax and then infected them with C. diff, and saw a similar trend. The mice exhibited a gradual decrease in C. diff intestinal levels over time, indicating that this bacterial “cocktail” capable of resisting C.diff colonization. 

These findings suggest that barring C. diff from the proverbial candy store may help prevent or treat CDI. More broadly, this study forms a basis for identifying gut bacteria with specific functions (e.g. sugar-eating) to inform the design of effective microbe-based therapeutics. 

Many people think that humans and chimpanzees are the only primates that eat meat. But scientists have known about widespread meat-eating in primates for decades. And, a recent review paper published in the Journal of Human Evolution has summarized all the data on meat-eating in primates to date. 

Over 89 species from 12 of the 17 families of of primates eat meat. These 89 species are scattered all over the world. Birds, including their eggs, are the most common primate prey, followed by reptiles, amphibians, mammals and even fish. Chimpanzees are the kings of variety, with 45 different vertebrate species appearing in their diets. 

But why to eat meat? Primates seem to be better off covering their calorie and protein needs by eating plants and invertebrates than by hunting. 

Most primates feed on meat sporadically, and it represents less than the 1 percent of the diet in almost all 89 species. There is no evidence that primates rely on meat for energy when other resources are scarce. The most likely explanation for meat-eating by primates at present is that meat provides micronutrients, such as vitamins and minerals, that are found in plants in only very small amounts. 

Human meat-eating is quite different from that of other primates. Meat is a key source of energy for many of us modern humans and our ancestors. And while other primates feed on prey much smaller than themselves, we hunt animals larger than ourselves. 

Throwing-weapons and other hunting tools play a considerable role in achieving this human feat. Some chimpanzees and capuchin monkeys do use tools like sticks for hunting. However, big game hunting from a distance seems to be exclusive to the human lineage.

CRISPR-Cas9 is the most precise and efficient gene editing system that exists. Now, researchers working with golden rice are focused on developing a Cas9 system that can insert a desired gene, rather than simply delete or mutate an existing one. 

As part of their study, published in Nature Communications, they successfully inserted a carotenoid-production gene into the plant. Carotenoids are the orange pigments found in carrots, bell peppers, and other similarly colored plants. They also give golden rice its color.

The researchers first needed to find locations in the golden rice genome where an insertion does not change the plant’s growth and development. They looked for plants that had extra piece of DNA but a normal phenotype relative to a normal golden rice plant. They found a few good candidates and used one of them to create a guide RNA, which tells the Cas9 enzyme where to cut the plant's DNA and insert the desired gene.

The researchers confirmed that the desired carotene gene had indeed been inserted by sequencing the plant's genome and comparing it to to the unaltered golden rice genome. They found one line of plants that had the gene and produced more carotene than its wild type counterpart.

If used to insert other types of genes into food crops, this approach could go a long way toward producing drought-tolerant, pest-resistant, and eco-friendly plants. 

Plastic is everywhere. Scientists have found tiny bits of microplastic even in the extremes of the Earth – from the deep-sea of the Mariana Trench to the peaks of the Pyrenees – and damaging life around us. While source reduction can be one of the most effective ways to reduce plastic waste, how do we deal with all of the plastic that already exists, polluting our oceans and overflowing out of landfills?

Polyethylene terephthalate, also known as PET and one of the most common types of plastic, is unfortunately notoriously difficult to break down. In 2016 however, scientists found a new species of bacteria outside of a bottle-recycling facility capable of decomposing plastic. The discovery revealed that the bacteria’s abilities depend on two specific enzymes. These enzymes work together in a two-step process to break plastic down into smaller molecules that the bacteria can turn into energy.

A new study published in the Proceedings of the National Academy of Sciences demonstrates a way to improve the two-enzyme system. While naturally existing as two separate enzymes – PETase and MHETase – the researchers physically linked them together. The attached enzymes worked together more efficiently than the same two enzymes when unlinked. Depending on the length of the linking segment between them, the attached enzymes were able to release almost double the amount or more of the final broken down product.

With this process, PET, could be broken down by the bacteria in days, a process which would take hundreds of years in the environment. 

But breaking down plastic only deals with part of the issue of plastic waste. Recovering the plastic waste already in the ocean and other corners of the planet to deliver to recycling or decomposing facilities remains a daunting challenge. And even faced with the knowledge that we need to reduce plastic, the world has only been ramping up its production levels. Although these results are exciting, we’re still far from solving our growing plastic problem.

Banded mongooses — which live in south-central Africa and look like a combination of a raccoon and a meerkat – are known for their violent intergroup battles. These conflicts are common. As many as three occur per month, often leading to injury, and sometimes death. But for a long time, scientists didn’t know why these little mammals were so prone to warfare.

A recent study analyzed 16 years of observational data to find out. Researchers found that males were more likely to shoulder the costs of battle — males made up almost all of the deaths in from intergroup fights. Females, on the other hand, almost never died in these skirmishes. While managing to avoid the negative effects of conflict, females did reap the rewards: the more conflicts her group engaged in, the more offspring she had whose fathers were not part of her own group. Since members of mongoose groups are often closely related, if the father belongs to a different group, the offspring are less inbred and more likely to survive.

Male mongooses practice mate-guarding: after mating with a female, they follow her around to make sure she doesn’t mate with anyone else. The authors suggest that because of this mate-guarding practice, the females will actually instigate fights so that, in the mayhem of battle, they can mate with the other groups’ males. While this practice is costly for the males, it’s an evolutionary advantage for females because it results in healthier offspring.

While pharmaceutical company Biogen continues fighting for FDA approval for their much-discussed Alzheimer's drug Aducanumab, a new drug may actually present a better option. Researchers at Nankai University and Peking Union Medical College recently showed that a synthetic molecule called 9i not only stops the physical manifestations of Alzheimer’s disease, but also restores the damage it causes to the brain in mice.

Alzheimer’s disease is a type of dementia that impacts brain structure, shape and function, to the point that patients lose significant portions of their memory and struggle to perform daily activities. As we still cannot pinpoint the cause of the disease, developing treatments remains difficult, notably in how to stop the disease and restore brain function, instead of only slowing the progressive memory loss. 

The scientists of this study created 9i from the base structure of tacrine, a compound previously sold under the name Cognex to treat mild to moderate Alzheimer's disease. Scientists eventually realized that tacrine caused fatal liver damage. Though no longer sold in the US, researchers occasionally use it to develop new compounds that they hope will keep the same positive effects but lose the negative effects. One daughter compound, 9i, seems to be following in its parent’s footsteps but with a much lower chance of causing tacrine’s liver toxicity.

The researchers fed 9i in low doses to Alzheimer’s disease-afflicted mice. Even at these low doses, they saw that the mice remembered new objects and navigated water mazes, two behavioral tests that evaluate object and spatial memory, significantly better than the placebo group. In addition, when examining the brains of these mice, 9i significantly decreased the number and severity of amyloid-beta fibrils, one of the physical signatures of Alzheimer’s. Most importantly, 9i boosted the amount of synapse-related proteins that are typically decreased in Alzheimer's and encouraged a greater density of dendritic spines, cell structures that contribute to memory. 

In essence, 9i seems to do what Aducanumab can, but with the added bonus of restoring the cellular structure of memory. 

These preliminary results show that it is possible to stop the disease and recover from its adverse effects. However, the real test will be if human clinical trails can replicate these findings and provide hope for those affected by Alzheimer’s disease.

Pre-eclampsia is a pregnancy complication characterized by high blood pressure and possible organ damage and is the second leading cause of maternal mortality. Though symptoms generally manifest late in pregnancy, low-dose aspirin therapy at 12-28 weeks can reduce risk but is only recommended for those with risk factors. However, most patients who develop pre-eclampsia do not have risk factors or a family history of the complication.

Therefore, identifying patients without known risk factors who may develop pre-eclampsia is an important advance, both for preventative treatment and for potentially enrolling patients in clinical trials for pre-eclampsia.

A recent paper published in the journal Cell has done just this. The researchers used extracellular RNA, which are small RNAs that are loaded onto proteins or into small packets of information called vesicles and released into body fluids, to identify women with a risk of developing pre-eclampsia. 

Using a technique called small RNAseq, they sequenced RNA in the blood samples of 212 women, 73 of whom had developed pre-eclampsia and 139 controls. They looked for RNAs that were present only in women who developed pre-eclampsia, then checked if those RNAs were found in the control cohort. They identified several miRNAs (one of many small RNA types) which could separate women who went on to develop pre-eclampsia from those who did not.

Creating this simple blood test could affect the outcomes of all patients without known risk factors for pre-eclampsia. Normally, they would be unaware of their risks and would not take preventative measures. The researchers are hopeful that this will eventually make its way into the clinic, where it could save many women's lives.

Why do teenagers take so many risks, and how does schizophrenia work in the brain? These two questions may share a common answer: they are possibly due to a type of brain cell called "in-between neurons." 

The brain still holds many mysteries; one of these is the in-between neurons. They are neither grey matter, the information processing center of the brain, nor are they white matter, where neurons are surrounded by a myelin sheath, a fatty layer needed for speedy signal transmissions.

In-between neurons are technically referred to as superficial white matter (SWM). They are special because they only have a thin layer of myelin, but not enough to make them visible under a microscope. Strangely enough, even though SWM only has a thin layer of fat, it is one of the last parts of the brain to fully develop.

Until now, scientists have been unable to view these lightweight neurons through a microscope. However, a European research group has now devised a simple solution to see them up close. They used ultra-high resolution brain imaging and found that iron was a good indicator of where SWM is located in the brain. They then developed a mathematical model to map the location of iron in SWM throughout the human brain, enabling them to non-invasively "see" these in-between neurons. 

Being able to get a more detailed picture of these SWM neurons will allow for greater understanding of the brain. Areas of the brain with SWM are important to the normal functioning of the brain and also in conditions such as schizophrenia and Alzheimer's. Finding out more about SWM's role in these conditions could help improve symptoms in those who have them.

The relationship between sound waves and human physiology is intricate. Immediately upon hearing a loud noise, a neurohormonal cascade of events is triggered inside of our bodies, and our stress hormone levels rise.

Evolutionarily, this is quite advantageous. If the sound was caused by lightning hitting the tree next to you, those stress hormones pumping through your body might save your life. 

But these fight-or-flight systems can be overstimulated. Living next to a noisy highway, for example, could keep stress hormones chronically elevated.

A recent review published in the journal Redox Biology showed a definite link between so-called “noise pollution” and the generation of molecules called reactive oxygen species (ROS) in our bodies. ROS can act on the thin lining of blood vessels by depleting nitric oxide, which keeps the vessels healthy by limiting constriction and preventing immune cells from aggregating along vessel walls. A lack of nitric oxide can increase a person's risk of high blood pressure, diabetes, and arterial plaque formation — all of which can contribute to cardiovascular and metabolic disease.

This research suggests that limiting exposure to noise pollution may be important in human health and longevity.

While many assume that early human societies had a stark division of labor — men were hunters, women were gatherers — new findings contradict this hypothesis. Researchers identified a 9,000-year-old burial site in the Andean highlands containing many tools that would have been used to hunt big game, likely Andean deer and vicuña (an animal similar to an alpaca). By analyzing peptides in the individual’s tooth enamel, researchers determined that the remains belonged to a young woman.

But was this female hunter an anomaly or was she one of many? Researchers turned to previously published studies to look for clues. They found 27 cases during a similar time period in the Americas in which individuals whose sex had been reliably determined were buried with hunting tools. Of these 27 hunters, 11 were female. Based on this, researchers estimated that women made up between 30 and 50 percent of the hunters during this time.

While scientists continue to study the effect of SARS-CoV-2 on humans, less work has focused on how susceptible other primates are to the virus. 

New research explored the likelihood that our primate relatives are susceptible to SARS-CoV-2 infection. The SARS-CoV-2 virus binds to a cellular receptor protein, the ACE2 protein. ACE2 resides on the surface of cells throughout the human body. When SARS-CoV-2 binds to ACE2, it overtakes the cell’s protein mechanisms, makes copies of itself, and the infection begins. 

This new research studied the characteristics of the ACE2 protein in 29 primate species, as well as four non-primate species for comparison. The researchers found that catarrhines, a group of monkeys and apes that live in Africa and Asia, are likely to be susceptible to a SARS-CoV-2 infection because their ACE2 proteins are similar to ours. This is supported by findings that biomedical populations of catarrhines, specifically rhesus monkeys, long-tailed macaques, and vervet monkeys have become infected with SARS-CoV-2 and expressed COVID-19-like symptoms. 

The platyrrhines (monkeys that live in the Americas) and  strepsirrhines (lemurs, lorises, and tarsiers) are generally less susceptible to contracting the disease. 

These results are important for our understanding of the novel coronavirus and for primate conservation during the COVID-19 pandemic. The endangered status of many non-human primates means that contracting the virus could be disastrous. For example, there are about 1000 mountain gorillas alive today and should that population become infected with SARS-CoV-2, the effect would be devastating. 

Over 250 million people live with depression. Unfortunately, the drugs used to treat depression also kill beneficial gut bacteria, and this may cause unpleasant side effects, including nausea, vomiting or diarrhea. People may even stop taking their medication because of these effects.

In a new study published in Scientific Reports, scientists examined the antimicrobial properties of different antidepressant drugs on common gut microbes. Studies continuing from this research could enable us to minimize these unpleasant side effects. Looking at someone's gut bacteria might also allow clinicians to select the ideal antidepressant treatment.

The scientists grew common gut bacteria on petri dishes and added varying doses of different antidepressants to measure how the drugs affected these gut bacteria. They found that different types of antidepressants inhibited the growth of common, and important, gut bacteria, and that desipramine and aripiprazole had the greatest effects on the bacteria.

There is growing recognition that future clinical trials will need to assess the effects of drugs on gut microbes. Tracking these effects in large clinical samples could help us determine why some antidepressants cause digestive problems. Long-term, these discoveries could enable the development of better treatments for depression with fewer side effects. 

Human communities rely on their relationships with the ocean. Marine systems provide humans with ecosystem services such as pollution filtration and shore protection. Societies living in marine areas also benefit economically through fisheries and tourism. However, humans are indirectly harming marine ecosystems through increased carbon dioxide emissions. When the ocean takes up carbon dioxide from the atmosphere, pH levels drop and the ocean becomes more acidic. This process is called ocean acidification.

A recent review paper in Annual Reviews of Environment and Resources synthesized the harmful effects of ocean acidification and how these effects impact human communities. They found that two types of marine ecosystems important for humans, oyster reefs and coral reefs, are particularly susceptible to ocean acidification. The oysters that make up oyster reefs will not be able to grow as thick of shells as usual in acidic ocean water and their offspring will struggle to survive. Coral reefs will also suffer as coral skeletons grow weaker and pH-tolerant algal species compete with corals.

These findings show that ocean acidification is a serious threat to marine ecosystems. The researchers conclude with several suggestions on how to lessen the effects of ocean acidification, the foremost being a reduction in carbon dioxide emissions. They also advocate for disaster risk reduction and flexible policies to protect vulnerable coastal human communities. 

Following the harassment of Christian Cooper in Central Park in May 2020, Black birders created #BlackBirdersWeek to celebrate Black nature enthusiasts and highlight their belonging in outdoor spaces. Since then, dozens of campaigns have emerged to amplify and appreciate Black academics, scientists, and naturalists. 

Next up is #BlackInMarineScienceWeek, running from November 29th to December 5th. Led by founder Dr. Tiara Moore and organizers Amani Webber-Schultz, Dr. Camille Gaynus, Carlee Jackson, Al Troutman, Jasmin Graham, Jeanette Davis, Kris Howard, Leslie Townsell, Kaylee Arnold, and Jaida Elcock, this week represents an opportunity for community building and improved representation.

“There are few Black folks in ecology and even fewer in marine ecology,” says Arnold, a science communicator and disease ecologist. “The network that I’ve gained through organizing this week is phenomenal. Meeting other Black marine scientists and showing that to the world, especially young Black folks, is a way to say we exist, we’re here. We have a full day dedicated to young kids, which is unique and exciting.” 

The organizers hope that the week will help normalize Black folks doing marine research, inspire younger generations, and remind everyone to check their preconceived notions.

"When I say I study sharks people seem concerned about my swimming or my hair, [and] sometimes respond with 'Oh, that’s super interesting'... I don’t know if that's because it's unusual for people to study sharks or because I’m Black and I study sharks,” recalls Elcock, an elasmobranch movement ecologist, science communicator, and co-founder of Minorities in Shark Science. “Science is for everybody. People say there isn't diversity because [Black] people aren’t interested... that’s clearly not true… there’s a whole week dedicated [to it]."

Discussion this week will address the fact that exclusion, not lack of interest, led to today’s lack of representation. Centuries of segregation and underinvestment in Black neighborhood pools led to, and are perpetuated by, these incorrect and harmful ideas.

“My grandparents and my mom said there were just no pools for her to go to... I had a very different experience. Despite people trying to push us out of the water and science, we persevered, and now we get to break down those stereotypes,” notes Arnold.

Black in Marine Science Week is here to do just that, showcasing organizers and participants from every imaginable marine science niche, all shaping how society views the oceans and its inhabitants.

“There's more Black folks than even we know and are showcasing. I hope that if the media picks up on the number of us as well, and has better representation. Seminar series are extremely white, and now you have a resource of people you can invite instead,” emphasizes Arnold, pointing to the necessity of non-Black marine scientists to step up and ensure representation continues beyond this joyous and educational week.

Human encroachment into wildlife habitat, especially streams and small rivers, is not good news for turtles. But one group of turtles may actually be making the best of a sticky situation: Eastern snapping turtles (Chelydra serpentina), a species of freshwater turtles commonly found across North America, have found a way to use culverts to their advantage. They use these tight spaces to ambush passing migratory fish.

A recent study tracked the predation habits of snapping turtles in and around culverts constructed near the Herring River in Massachusetts. The area sees seasonal migrations of river herring. Like salmon, river herring are born in freshwater, live their lives in the ocean, and return to freshwater to spawn. All this back and forth movement means that the herring have to cross many culverts, which act as bottlenecks and slow down the passage of fish. 

At the Herring River culverts, researchers used video cameras to track the movements of fish and the predation habits of turtles. Along with the migratory herring, they also tracked the resident fish that live in these rivers all year round and are familiar with the culverts. 

The scientists found that resident fish avoided the center of the tunnels in culverts where snapping turtles lay in wait, successfully avoiding becoming a turtle's meal. The herring, on the other hand, did not learn to avoid the turtles and were caught more often. The turtles, in turn, preferred to target the herring, which tended to swim lower and were easier for them to catch.

The study showed how the snapping turtles used the culverts and quickly learned to target the naïve herring over the experienced resident fish. The turtles also seemed to slow down the overall movement of herring as these fish eventually started avoiding culverts that had turtles. Although the culverts might allow good eating for the turtles, the researchers caution that this could potentially delay fish migration in the long term if the herring are scared off of culverts altogether.

Due to increasing global trade and travel, non-native species have arrived on every continent. Some of these species become invasive, and they have long been thought to possess special traits allowing them to flourish in their new environment.

As climate change shifts the parameters of our environment, species — invasive and otherwise — must adapt to new challenges. Though researchers have long believed that invasive species are better able to adapt to novel climate conditions, a recent study finds that invasive alien ant species showed less colonization of new climate types than non-invasive alien species.

If the set of climate, habitat, and resource conditions an organism exists in is its niche, then a niche shift is an expansion or contraction of those conditions. By analyzing a global database of ant range information, scientists in Switzerland and France found that the greatest predictor of niche shifts for ants is not their invasiveness, but their native range and niche size.

This study paints a more hopeful picture of the dual threats of climate change and invasive species — two of the greatest threats to biodiversity worldwide. If climate change does not accelerate invasive species’ range expansion, as previously thought, the interaction of these two factors may not be as dire. 

However, these findings point back to the evergreen question: Which factors make a species invasive? For ants, at least, it seems as though the ability to niche shift is not one of them.

Wind power is a promising renewable source of energy and wind farms are becoming increasingly more common. However, there is a concern for their impact on wildlife, in particular as collisions with them cause the deaths of thousands of bats and birds every year.

Based on previous work, a team of researchers led by Roel May from the Norwegian Institute for Nature Research set out to test whether painting one of the blades of the turbines would increase their visibility and reduce avian fatalities. They tested their prediction at a wind-power plant in the Smøla archipelago in Norway, an area designated to be Important Bird Area by Birdlife International, where researchers have collected avian fatality data since 2006.

Out of four turbines, one was painted black and the other three were left unpainted. Fatality data from searches at the base of the turbines over three-and-a-half years showed that black paint reduced the annual rotor blade fatality rate by 70 percent.

Birds of prey, such as the white-tailed eagle, benefited the most and accounted for the largest observed decline in death. The authors attribute this to the species' excellent vision.

Their data does not indicate that birds became familiar with the painted turbines. They say this is a good thing, as fatalities could increase if birds habituate to the changes.

These findings still need to be replicated in other studies. However, the authors suggest that such a strategy could be more easily put in practice before building the turbines, because painting blades with the turbines already set in place was a demanding task. As wind-power plants become more common, their impact should be reduced as much as possible. Painting their blades may be one way to go.

Exercise is hard. It’s even harder if your muscles can't get the oxygen they need. This physiologic challenge is known as hypoxia. When muscles are hypoxic, they often can’t work as hard. Atop a mountain in Colorado, atmospheric pressure is much less than it is at sea level. Even though the percent of oxygen molecules found in the air is the same, there is less driving force for that oxygen to get into the body.

If an individual has a physical condition, such as congestive heart failure or COPD, which impedes the body’s ability to capture and transport oxygen to exercising muscle, similar hypoxia could occur. Sports scientists and doctors can simulate these conditions in healthy participants by restricting the amount of oxygen they breathe through special masks or low-oxygen chambers.

New research shows that these two causes of hypoxia have different effects on exercise performance. Researchers combined 21 previously published studies which evaluated exercise capacity under the simulated normobaric hypoxia (NH) and high-altitude hypobaric hypoxia (HH) in athletic men. These studies included two different exercise methods: running and cycling.

As expected, participants’ maximal exercise capacity was impaired under both NH and HH conditions. However those in HH performed slightly better than those in NH — perhaps because of lower air resistance making it easier to breathe. And between those who ran or cycled, those who ran had lower blood-oxygen levels and lower heart rates. There was no difference between running and cycling seen in NH. 

These insights may allow athletes and doctors to better predict how they or their patients will respond to exercise in low oxygen environments.

Bees are critical to the survival of myriad ecosystems around the world, and their pollination is worth billions of dollars every year in the U.S. and abroad. Their populations have been declining for decades due to climate change and habitat loss, posing a threat to global food security.

Agricultural yields can be threatened by a simple decrease in bee populations, as well as by changes to the crops' growing seasons and the bees' flight and pollination seasons. If the crops are ready to be pollinated but the bees aren't around to do the job — no luck.

While changes to bee species' abundances and diversity have been well-studied, biologists don't yet know how in sync bees are with crops from region to region, or how that's changed over time. A new study in Global Change Biology examined how wild bee populations in Belgium have shifted when and how long they're active — their "flight period" — over the past 70 years.

The study found that 61 percent of Belgium's wild bees declined over that time span, but not all bee species had the same response to climate and land-use changes. There are "winners" and "losers": southern bees adapt more readily to warmer temperatures, and bees with bigger ranges can cope better with land-use change. That makes generalizing predictions about future changes tricky.

Additionally, two of the bees' behaviors, flight period and occupancy (range), varied by species. Those behaviors are affected by temperature changes and agricultural expansion, both of which increased over 70 years. As a result, the bees' pollination season was 9-15 days shorter and started a few days earlier.

With an estimated 11 percent of crops in Belgium depending on pollination for success, that's a significant shift. The timing of crops' growing season and bees' pollination is a delicate balance. While wild bees' pollinating can be supplemented with domestic hives, it can be less efficient than wild pollination and, because wild bees are free, it's always more expensive.

Bees' critical role in agriculture isn't new, but scientists are just beginning to understand their complex responses to climate change and agriculture, and what that means for pollination seasons. Until more research is done, changes to pollination seasons will remain up in the air.

Last week, Utah's Division of Wildlife Resources released a video of the state's first ever wildlife overpass. The project, which allows animals to move across a landscape increasingly covered in roads, appears to be a success.

Roads, especially busy, high-speed ones, pose an enormous risk to animals such as coyotes, moose, and bears. Traffic accidents are a leading cause of death for large mammals in North America, in addition to being very dangerous for people driving the vehicles that collide with these animals. Roads and private lands also slam the door on vital animal movement corridors, keeping populations of animals restricted to smaller ranges. This restriction leads to less genetic diversity and greater susceptibility to local natural disasters, such as fires.  

Human-made corridors are a popular solution allowing wildlife to travel safely across human-impacted landscapes. In this case, Utah DWR's video shows an highway's abandoned overpass converted to safe walkway for the state's abundant wildlife.

The full video is worth a watch, but here are some fun screengrabs for your pleasure as well, all courtesy of Utah DWR's public video.