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Monitoring Wildlife For Warning Signs of the Next Pandemic | Earth Wise

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According to the World Health Organization, the coronavirus that causes COVID-19 likely originated in wild bats near Wuhan, China, and may have been passed to a second animal species before infecting people.  Since then, according to data from Johns Hopkins University, more than 13 million people around the world have been infected by COVID-19 and about 600,000 have died. 

But despite the ever-present threat of a new virus sparking the next pandemic, there is currently no global system to screen for viruses in wild animals that could eventually spill over to humans. 

In an article recently published in the journal Science, a group of scientists is calling for the creation of a decentralized global system of wildlife surveillance.  The establishment of this global system could help identify viruses in wild animals that have the potential to infect and sicken people before another global disease outbreak begins. 

According to the scientists, coronaviruses alone have caused outbreaks in humans three times in the last 20 years:  SARS (or Severe Acute Respiratory Syndrome), MERS (or Middle East Respiratory Syndrome), and COVID-19. 

While it’s impossible to know today how often viruses jump from animals to humans, human activity is making such spillover events more and more likely.  For instance, many continue to develop wild animal habitat to build new homes or businesses.  Some catch wild animals and re-sell them either for consumption or as exotic pets.  Parts from these wild animals are often shipped around the world as trinkets or as ingredients for traditional medicines. 

A global system that could identify potentially harmful viruses before they jump to humans is technologically feasible, affordable, and clearly necessary. 

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COVID-19 Dashboard by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU)

Global wildlife surveillance could provide early warning for next pandemic

Photo, posted January 15, 2008, courtesy of Doug Beckers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The United States And Ticks | Earth Wise

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Tiny ticks are a big problem.  Measuring only three to five millimeters in size, ticks are widely distributed around the world.  They are external parasites, feasting on the blood of birds, reptiles, amphibians, and mammals – including humans.

According to estimates from the Centers for Disease Control and Prevention, ticks infect more than 300,000 people with Lyme disease in the United States every year, and the numbers continue to rise.  Other common tick-borne diseases include anaplasmosis, babesiosis, Rocky Mountain Spotted Fever, and powassan encephalitis.

But while the prevalence of tick-borne illnesses has steadily increased in the United States over the past two decades, a new study on tick surveillance and control “has revealed an inconsistent and often under-supported patchwork of programs across the country.”

The study, by university researchers at the CDC’s five Vector-Borne Disease Regional Centers of Excellence, is the first-ever examination of tick management programs in the United States.  The researchers found clear gaps in our public health infrastructure. 

According to the study, which was recently published in the Journal of Medical Entomology, less than 50% of public health and vector-control agencies conduct tick surveillance.  Only 25% test ticks for disease-causing germs.  And only 12% conduct or support tick-control efforts.  Researchers also discovered that the capacity for public tick-control efforts is low, as is the capacity for information and data sharing between agencies on ticks.    

The findings highlight the degree to which tick surveillance and control is lagging in the United States.  According to the research team, greater support for tick-management programs is critical, and they hope their findings will serve as a baseline from which to measure future improvements.  

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Tick surveillance and control lagging in US

Photo, posted May 4, 2009, courtesy of Jerry Kirkhart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

PFAS In The Food Chain | Earth Wise

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Per- and polyfluoroalkyl substances (PFAS) are a family of human-made chemicals that have been manufactured and used in a variety of industries around the globe.  PFOA and PFOS have been the most extensively produced and the most extensively studied of these chemicals. 

Exposure to PFAS has been linked to a host of adverse health effects, including thyroid hormone disruption and cancer.

PFAS compounds can be found in such things as non-stick cookware, stain-resistant carpets, water-repellent outdoor gear, and food packaging, like fast food wrappers and microwave popcorn bags. 

According to a new study, researchers from North Carolina State University have found PFAS substances in every step of the Yadkin-Pee Dee River food chain, even though the river doesn’t have a known industrial input of these compounds. 

The team collected water, sediment, algae, plant, insect, fish, crayfish, and mollusk samples at five sites along the river and analyzed them for 14 different PFAS compounds.  Nearly every sample tested contained PFAS compounds.  Biofilm contained the largest concentrations of 10 of the 14 PFAS compounds measured.  Insects, which primarily eat biofilm, had the greatest accumulation of PFAS compounds of all the living taxa the researchers sampled. 

When PFAS compounds are present at every step of the food chain, the compounds accumulate at each step leading to greater concentrations in animals that sit higher on the food chain – including humans.  This is known as biomagnification. 

Studies like this that reveal how prevalent PFAS can be within ecosystems without an industrial input highlight the need for further research into how these compounds affect the environment and human health.

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PFAS present throughout the Yadkin-Pee Dee river food chain

Photo, posted May 24, 2011, courtesy of the U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

PPE Pollution | Earth Wise

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While the COVID-19 pandemic and its shutdown of so many human activities has reduced many kinds of pollution, it has also managed to create a new source of pollution:  face masks and sanitary gloves.

Divers from a French non-profit organization called Operation Clean Sea are already finding gloves, masks, and hand sanitizer bottles beneath the waves of the Mediterranean, along with the usual litter of disposable cups and aluminum cans. In France, authorities have ordered 2 billion disposable masks. Given that, there may soon be the risk of having more masks in the Mediterranean than jellyfish.  In Hong Kong, face masks have been piling up on beaches and nature trails.  Even in Hong Kong’s isolated and uninhabited Soko Islands, dozens of masks are showing up on a small stretch of beach.

Disposable masks may feel like soft cotton, but almost all of them are made from non-biodegradable material such as polypropylene.  When such masks are discarded into storm drains, they end up in rivers and seas.  With a lifespan of hundreds of years, these masks are an ecological timebomb.  Land-based activity accounts for 80% of ocean pollution, and half of that is a direct result of single-use plastics.  Many of the CDC’s recent recommendations for reopening offices and businesses actually recommend the increased use of them, and for sensible reasons.

The best we can all do is to wear reusable masks and to try to wash our hands more often rather than putting on another pair of latex gloves.  Given that there are alternatives, we don’t need to make plastic the solution to protect us from Covid-19.

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COVID-19 Masks Are Polluting Beaches and Oceans

Photo, posted March 28, 2020, courtesy of Michael Swan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Animals And Social Distancing | Earth Wise

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As the spread of COVID-19 continues throughout the U.S. and around the world, health officials continue to ask people to keep physical space between themselves and others outside their homes.  It’s an important and effective way to slow down and prevent the spread of disease. 

But it’s not just humans who can benefit from social distancing.  It turns out that animals can, too.

Microorganisms living on or inside our bodies are important for both our health and for the development of disease.  Researchers from the University of Texas at San Antonio have found evidence for the importance of social distancing to minimize the spread of microbes among individuals.   The researchers studied wild monkeys to find out what role diet, genetics, social groupings, and distance in a social network play when it comes to the microbes found inside the gut.  The gut microbiome refers to all the microorganisms living in the digestive tract. 

The research team studied the fecal matter of 45 female colobus monkeys that congregated in eight different social groups in a small forest in Ghana.  The researchers observed major differences in gut microbiomes between the eight social groups.  But individual monkeys from different groups that were more closely connected to the population’s social network had more similar gut microbiomes.  The findings, recently published in the journal Animal Behaviour, indicate that microbes may be transmitted between monkeys during occasional encounters with other monkeys from different social groups.

Learning how microorganisms pass among monkeys can help researchers understand how diseases spread.  Understanding how diseases spread can help guide decision making during this pandemic and any future disease outbreaks. 

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Even animals benefit from social distance to prevent disease, research shows

Photo, posted January 10, 2007, courtesy of Silke Baron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastic Hotspots In The Ocean | Earth Wise

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Many of us are aware of the infamous ocean “garbage patches” of floating plastic.  The Great Pacific Garbage Patch is roughly the size of Texas.  But over 10 million tons of plastic waste enter the oceans each year and the floating patches only account for 1% of that total.  The remaining 99% of the plastic ends up in the deep ocean, generally in the form of microplastics – tiny fragments of large plastic debris that have broken down as well as manufactured polyethylene beads used in various products.

According to a new study published in the journal Science, there are actually microplastic hotspots on the ocean floor, formed by deep-sea currents that act as conveyer belts moving the tiny plastic fragments around.  One of these hotspots – in the Tyrrhenian Sea off the west coast of Italy – contained 1.9 million microplastic pieces in just one square meter of seafloor.  This is the highest reported value for any place in the world.

Because of their small size, microplastics can be ingested by organisms across all levels of the marine food chain and eventually find their way into human diets. 

The spatial distribution and ultimate fate of ocean microplastics are strongly controlled by near-bed thermohaline currents.  These are deep-ocean currents driven by differences in water density, which is controlled by temperature and salinity.  Thermohaline currents are known to supply oxygen and nutrients to the flora and fauna found at the ocean bottom.  As a result, deep sea biodiversity hotspots are likely to be in same places where there are microplastic hotspots.

The discovery of these deep- sea hotspots is just another reason why we need behavior and policy interventions to limit the flow of plastics into natural environments.

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Seafloor microplastic hotspots controlled by deep-sea circulation

Photo, posted September 6, 2012, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Living In Extreme Heat | Earth Wise

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Global climate change has already left observable effects on the planet.  Glaciers have shrunk, trees are flowering sooner, plant and animal ranges have shifted, and so on. Many effects of climate change that scientists had predicted in the past are now occurring.  The loss of sea ice, intensifying heat waves, and accelerating sea level rise are some examples.

According to a new study recently published in the journal Proceedings of the National Academy of Sciences, climate change is going to affect humans earlier, harder, and more widely than previously projected.  The research team found that one billion people will be either displaced or endure insufferable heat for every one degree Celsius rise in global temperatures.  

Under a worst case climate scenario, land that one third of the world’s population currently calls home will be as hot as the hottest parts of the Sahara desert within 50 years.  Even under a more optimistic climate outlook, 1.2 billion people will still be exposed to temperatures outside the climate niche in which humans have thrived for at least 6,000 years.

The majority of the human population has always lived in regions where the average annual temperatures were between 43 degrees Fahrenheit and 82 degrees Fahrenheit.  These are ideal temperatures for human health and for food production.  But this temperature range is shrinking and shifting as a result of climate change. 

The study’s authors predict there will be more change in the next 50 years than there has been in the past 6,000 years.  They hope their findings will convince policymakers to accelerate their plans for emissions reductions and other climate mitigation strategies.   

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Future of the human climate niche

One billion people will live in insufferable heat within 50 years – study

Photo, posted November 22, 2008, courtesy of Ronnie Finger via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildlife Reclaims Yosemite National Park | Earth Wise

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Our stories often discuss how human activities change the natural environment.  With most of us confined to our homes, the lack of human activities is having profound effects on the environment.  We are talking about some of these this week.

Yosemite National park is normally awash in humanity – there were over 300,000 visitors in April of 2019 and typically 4 million people visit each year.  But as of March 20, the park was closed to tourists to prevent the spread of the coronavirus.  Only a skeleton crew of employees remains in the park.

Without all the people, wildlife is coming out of hiding.  It did so in previous park closures during government shutdowns, but those closures were pretty short.  This one is expected to be the longest on record.

The bear population within the park has quadrupled and many larger animals – such as bobcats and coyotes – are congregating outside of cabins and other buildings and prowling empty roads and walkways instead of hanging back at the edges of human settlements. 

In addition, the air at Yosemite is cleaner due to the lack of exhaust and diesel, and Yosemite Valley is nearly silent, apart from natural sounds from the river and the wind.  According to some observers, the park’s current condition is probably similar to what visitors in the 19th century witnessed. 

The few park employees sheltering in place are taking advantage of the virtually unimpeded natural amenities of the park.  Many are hiking to its lakes and waterfalls, enjoying trails that are empty apart from animals.  As some of the people staying in the park have noted, one could not ask for a better place to be isolated.

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Coyotes, bobcats and bears: Wildlife is reclaiming Yosemite National Park

Photo, posted October 30, 2019, courtesy of Ania Mendrek via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coronavirus Shutdowns And The Environment | Earth Wise

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Our stories often discuss how human activities change the natural environment.  With most of us confined to our homes, the lack of human activities is having profound effects on the environment.  We are talking about some of these this week.

The COVID-19 pandemic is a global catastrophe, but it has ironically been a boon for the environment.  By taking billions of people off the streets around the globe and slashing all forms of travel, the global environment has seen dramatic changes.

Sea turtles in many countries are prospering by not having to compete with humans for precious beach space.  Animals everywhere have more freedom to roam and are taking advantage of the opportunity. The Himalayas are visible from parts of India for the first time in decades.

Satellite imagery has shown dramatic drops in nitrogen dioxide emissions in China, where pollution from vehicles is a serious public health problem.  Similar reductions in air pollution are evident in India, Italy and even in Los Angeles.  The city that is notorious for its smog suddenly has pristine air.

In Venice, water in the canals has become clear in the absence of heavy boat traffic stirring up sediments from the bottom.  Wildlife that normally is invisible such as jellyfish are being spotted.

Not all the changes to animal behavior are desirable.  Some wildlife that have become dependent on humans as a source of food are becoming aggressive and are taking to the streets of cities to look for food.  Monkeys in Thailand are mobbing towns and brawling, hunting for things to eat.  Rats in New York City are fighting over suddenly meager food supplies.

In many ways, the natural world is reacting to much of humanity sheltering in place.

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On Earth Day 2020, coronavirus shutdowns are a gift to the environment

Photo, posted April 2, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Too Many Bison | Earth Wise

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The population of large herbivores in Yellowstone National Park has undergone many dramatic changes over the course of time.  The numbers of both the iconic Rocky Mountain elk and bison have gone up and down as a result of human interactions.

Bison, of course, once were a dominant species from east of the Appalachians to west of the Rocky Mountains, with most of an estimated 30 million living on the Great Plains.  As the west was settled, bison populations plummeted and by the late 1800s, they were nearly extinct.

When Yellowstone was established, there were exactly 22 bison in the park.  By 1925, there were more than 750 in the park and culling of the herd in the park’s Lamar Valley was practiced for the next four decades.

The elimination of predators like grey wolves and cougars in the early 1900s caused both elk and bison populations to mushroom and both underwent culling.  When culling was ended in 1968, there were 4,000 elk and 100 bison.  Within 20 years, those numbers were 20,000 and 1,000.   Reintroducing wolves and cougars reduced the elk population to about 5,000, but bison numbers have continued to grow, now reaching about 4,000.

While the long-term recovery of the Yellowstone bison herd is a major conservation success story, the fact is that bison are powerful ecosystem engineers.  Large numbers of them disrupt species distribution across scrub steppe and grasslands because of what they eat, trample, and rub their horns and bodies on.  They have a tremendous capacity to limit the structure and composition of ecosystems.

Park administrators have complicated management decisions to make to take into account the often wide range of ecological effects that abundant large herbivores can have on ecosystems.

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Bison in northern Yellowstone proving to be too much of a good thing

Photo, posted August 10, 2016, courtesy of Brian Gratwicke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Boutique Hotels For Birds | Earth Wise

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The changing Arctic climate has had a drastic effect on its seabirds.  In fact, seabirds worldwide are in crisis, with global populations plummeting nearly 70% over the past 70 years as a result of climate change, over-fishing, habitat loss, and other human impacts on their environment.

Above the Arctic circle in Norway, seabird behavior has changed dramatically.  Black-legged kittiwakes – which are the most seafaring member of the gull family – used to nest in cliffs over the ocean and seldom ventured inland.  But in recent years, that has changed.  Because of a warming ocean, increased storminess and other changes that are decimating chick populations in their normal habitat, the birds have been setting up housekeeping in places like shopping centers and office buildings in Tromsø and other towns along Norway’s north coast.

Tromsø, Hammerfest and other towns at the very north end of Norway have become very popular with tourists seeking the Northern Lights and wanting to see glaciers before they disappear.  The booming tourism has been put on hold for the moment as it has elsewhere, but when it returns, the regions growing hotels and shopping areas are facing a problem.

The birds taking up residence on these buildings are unpleasant neighbors.  They are especially noisy during the breeding season and people are having to put up nets or spikes on buildings to discourage the kittiwakes from settling there.

Local ecologists are now building boutique hotels just for kittiwakes. Using abandoned buildings on piers, they are adding ledges for nesting, materials for nest-building, and electronic speakers that croon kittiwake songs.  The hope is that the birds will stay in their own hotels and leave the other ones for the human tourists.

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Norwegians are building boutique hotels for threatened Arctic birds

Photo, posted April 14, 2018, courtesy of Charlie Jackson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Devastating Threat To Coral Reef Habitats | Earth Wise

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According to new research from scientists at the University of Hawaii Manoa, the warming and acidifying oceans could wipe out nearly all existing coral reef habitats by 2100.  In fact, the researchers predict that 70-90% of coral reefs will disappear over the next 20 years alone as a consequence of climate change and pollution. 

Some organizations are attempting to save coral habitats by transplanting live corals from labs to reefs.  The idea is that the new young corals will help revive the reefs.  But after mapping where such restoration efforts would be most successful, the research indicates that there will be little to no suitable habitat remaining for corals by 2100.  Small portions of Baja California and the Red Sea are two of the sites that could remain viable by 2100, although neither are ideal due to their proximity to rivers.  Sea surfaces temperature and acidity are two of the most important factors in determining the viability of a site for restoration.  

Warming ocean waters stress corals, which cause them to expel the symbiotic algae living inside them.  This turns the often colorful corals white – an event known as coral bleaching.  Bleached corals are not dead corals, but they are at a higher risk of dying.  These coral bleaching events are becoming more frequent as a result of the changing climate. 

The projected increases in human pollution will only play a minor role in the future elimination of coral reef habitats.  Ironically, that’s because humans have already caused such extensive damage to coral reefs that there aren’t many locations left to impact.

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Warming, acidic oceans may nearly eliminate coral reef habitats by 2100

Photo, posted September 28, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coastal Plants And Climate Change | Earth Wise

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Rising sea levels and the increased frequency and intensity of extreme weather events are leaving observable effects on beaches, cliffs, and coastal infrastructures all around the world.  But a new study suggests that the impact of climate change on coastal plant communities needs more attention. 

According to research recently published in the journal Annals of Botany, coastal plants are a critical element of global sea defense.  But coastal plants are increasingly under threat from flooding, erosion, and other human-induced effects of climate change.  Habitats like salt marshes, mangrove forests, sand dunes, and kelp beds make important contributions  to coastal protection.

The research was led by scientists from the University of Plymouth, in conjunction with researchers at Utrecht University and Manchester Metropolitan University.

The study follows a recent assessment by the Intergovernmental Panel on Climate Change, which found that anthropogenic climate change poses a severe threat to estuaries and coastal ecosystems.  

Conservative estimates of the capital investments needed to combat rising seas and intensifying storms run into the hundreds of billions of dollars in the coming decades.  However, coastal vegetation could offer a dynamic, natural, and relatively low-cost defense strategy at a fraction of the cost when compared with the cost of so-called hard defenses like concrete walls and barriers. 

According to the research team, identifying the key species and habitats for coastal defense and how coasts can be protected and promoted is critical.  More long-term monitoring is also needed in order to better understand and predict where and how storms and other effects of climate change will impact coastal ecosystems. 

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The gathering storm: optimizing management of coastal ecosystems in the face of a climate-driven threat

Losing coastal plant communities to climate change will weaken sea defences

Photo, posted September 14, 2018, courtesy of Dennis Jarvis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

What Is An Endangered Species? | Earth Wise

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Biodiversity is declining rapidly throughout the world and people are mostly the reason.  Species are disappearing because of changes in land and sea use, the direct exploitation of organisms, climate change, pollution, and invasive alien species resulting from globalization.  The challenges of conserving the world’s species are many and difficult.  Among these challenges are determining which species are endangered and how and when to protect them.

What constitutes an endangered species is not necessarily obvious. 

Extinction risk increases as a species is driven to extinction from portions of its natural range.  Most mammal species have already been driven to extinction from half or more of their historic ranges because of human activities.

According to a recent survey of ordinary Americans, three-quarters of participants said that a species deserves special protections if it had been driven to extinction from any more than 30% of its historic range.  This compares with the language of the U.S. Endangered Species Act that defines an endangered species as one that is “in danger of extinction throughout all or a significant portion of its range.”

Experts and decision-makers are more accepting of risks and losses because they believe greater protection would be impossibly expensive.  Decision-makers tend to be influenced by special interest groups with a vested interest in not instituting protections.

Before human activities began elevating extinction risk, a typical vertebrate species would have experienced an extinction risk of 1% over a 10,000-year period.  Current policies consider a 5% risk over 100 years to be acceptable.  Policies consider whether we can afford to protect species.  Given the dangers of declining biodiversity, we should ask whether we can afford not to.

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What Is An Endangered Species?

Photo, posted July 29, 2018, courtesy of Sergio Boscaino via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Engineering Mosquitoes | Earth Wise

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Tropical regions grapple with the spread of diseases – such as dengue, yellow fever, zika, chikungunya, and malaria – by mosquitoes.  A fairly successful strategy has been the Sterile Insect Technique, which is essentially insect birth control. The process involves rearing large quantities of sterilized male mosquitoes in dedicated facilities, and then releasing them to mate with females in the wild. As they do not produce any offspring, the insect population declines over time.

A problem with this approach is that while mosquitoes create health problems for people, they also play important roles in various ecosystems, such as providing food for bats and other animals.  Eliminating mosquito populations on a large scale can trigger major changes in ecosystems.

Recently, an international team of scientists has synthetically engineered mosquitoes that halt the transmission of the dengue virus.  They genetically engineered mosquitoes with an antibody “cargo” that gets expressed in the female mosquitoes that spread the dengue virus.  Once the female mosquito takes in blood, the antibody is activated which hinders the replication of the virus and prevents its dissemination throughout the mosquito, thereby preventing its transmission to humans. Essentially, what the researchers have done is transfer genes from the human immune system to confer immunity to mosquitoes.  The researchers are testing methods to neutralize mosquitoes against other viruses they spread.

This opens up a whole new approach to interrupt mosquito-borne human diseases.  Mosquitoes are among the deadliest killers on the planet because they are the messengers that transmit deadly diseases.  Until now, the only real solution has been to kill the messenger.  The new approach may be a better way to deal with a serious problem.

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Mosquitoes engineered to repel dengue virus

Photo, posted June 20, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conspicuous Consumption

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Human civilization consumes vast amounts of material.   The Circle Economy think tank actually puts some numbers on it.  According to their latest report, the amount of material consumed by humanity has passed 100 billion tons every year.  So, on average, every person on Earth uses more than 13 tons of materials per year.

That number has quadrupled since 1970, which is far faster than the population, which has only doubled during that time.  In the past two years alone, consumption has jumped by more than 8%.  While this has been going on, the proportion being recycled has been falling.

Of the 100 billion tons of materials, half of the total is sand, clay, gravel, and cement used for building, along with other minerals used for fertilizer.  Coal, oil and gas make up 15% and metal ores 10%. The final quarter are plants and trees used for food and fuel.  About 40% of all materials are turned into housing.  A third of the annual materials consumed remain in use, such as in buildings or vehicles.  But 15% is emitted into the atmosphere as greenhouse gases and a third is treated as waste.

The global emergencies of climate change and disappearing wildlife have been driven by the unsustainable extraction of fossil fuels, metals, building materials, and trees.  The authors of the report warn that if we continue to treat the world’s resources as limitless, we are heading for a global disaster.

The Circle Economy think tank promotes the idea of a circular economy in which renewable energy supports systems where waste and pollution are reduced to zero.  Some nations are taking steps towards circular economies, while others are not.  This is a problem we can’t allow to be unaddressed.

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World Consumes 100 Billion Tons of Materials Every Year, Report Finds

Photo, posted March 13, 2015, courtesy of Joyce Cory via Flickr.

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Narwhal Tusks And Stories Teeth Can Tell | Earth Wise

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Teeth and particularly narwhal tusks are getting some unusual press recently when one of them was the weapon of choice to fend off the London Bridge attacker, which was a good choice according to Harvard dental researcher Dr. Martin Nweeia.  Turns out that narwhal tusks have some pretty amazing physical features.  They exhibit both extreme strength and flexibility at the same time.  The narwhal is known as the unicorn of the sea, a pale-colored, medium-sized whale found in Arctic coastal waters and rivers.  In males, the more prominent tooth grows into a sword like, spiral tusk up to 8.8 feet long.

Changes in the shape of teeth over time can tell us about climate change. Adaptations in horse teeth 55 million years ago from North America were observed and caused by changes in climate, favoring different food sources.  The horses changed their diets from fruit to more favorable grasses and their teeth changed in response. For this same reason, the teeth of elephants adapting in different environments of Asia and Africa have different tooth forms.  Both eat plants but Asian elephants, with more ridges on their teeth, eat larger amounts of grasses while African elephants, with wider spread ridges, eat more leaves. 

Teeth have been used to link land mass theories like the Bering Land Strait Theory, hypothesizing that North America and Asia were once one land mass. The teeth shape and form of people on both sides of the Bering Land Bridge shared a common “mongoloid dentition” with unique features. And so, can the narwhal tusk tell us something about a changing Arctic?  Scientists have discovered that the narwhal tusk is a giant sensory organ that is able to continually monitor its environment and has the ability to detect ice formation, and melt, both capabilities helpful for surviving in a changing Arctic.

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–Earth Wise acknowledges script contribution from Dr. Martin Nweeia of Harvard University.

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Fossil teeth reveal new facts about a mass extinction 260 million years ago

From the Horse’s Mouth: Teeth Reveal Evolution

Photo, posted April 3, 2019, courtesy of James St. John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Much More Microplastics In The Ocean | Earth Wise

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We’ve been hearing more and more about plastic contamination (microplastics) in the ocean.  It is pulled from the nostrils of sea turtles, found in Antarctic waters, and tracked in increasing quantities in sedimentary layers dating back to the 1940s.  A new study by researchers from the Scripps Institution of Oceanography suggests that there could be a million times more pieces of plastic in the ocean than previously estimated.

Oceanographers found that some of the tiniest countable microplastic particles in seawater occur at much higher concentrations than previously measured.  Apparently, the traditional way of counting marine microplastics most likely misses the smallest particles, and therefore underestimates the number of particles by a factor of anywhere from 10,000 to a million.

The new measurements estimate that the oceans may be contaminated by 8 million pieces of so-called mini-microplastics per cubic meter of water.  Earlier studies that only looked at larger pieces of plastic found only 10 pieces per cubic meter. 

Microplastic studies typically trawl or pull a fine net behind a ship to collect samples.  But the meshes previously used could only capture plastics as small as 333 microns.  The new study found plastic particles as small as 10 microns, which is less than the width of a human hair.

Plastics keep breaking down into smaller and smaller particles, but they are so chemically strong that their chemical bonds don’t break down. They remain bits of plastic.  Scientists are concerned that these particles can get small enough to enter the human bloodstream.  The potential effects on human health are not well known and not extensively studied.

The problem of plastics just keeps getting bigger.

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Microplastics a million times more abundant in the ocean than previously thought

Photo courtesy of UC San Diego.

Earth Wise is a production of WAMC Northeast Public Radio.

How Environmentally Friendly Are We? | Earth Wise

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Many of us are very concerned about the environment and want to try to do the right things as we go about our daily lives.  New research from the University of Gothenburg shows that we tend to overestimate just how much we are actually doing.

A study of over 4,000 people in United States, England, India, and Sweden revealed that most people are convinced that they act more environmentally friendly than the average person.  Their actions might include buying eco-labelled products, saving household energy, recycling, driving a hybrid or electric car, and reducing purchases of plastic bags.  Participants in the survey rated themselves as more environmentally active than other people, including both unknown people as well as their own friends.

The results are in keeping with a general tendency people have to overestimate their own abilities.  Studies over the years have shown that most people consider themselves, for example, to be more honest, more creative, and better drivers than others.  This sort of over-optimism apparently also applies to environmentally friendly behaviors.

The data from the survey revealed that the participants were more likely to overestimate their engagement in activities they perform often and draw the faulty conclusion that the things they do often, they in fact do more often than others.

A consequence of thinking that you are more environmentally friendly than other people is that it can reduce the motivation to act environmentally friendly in the future.  In fact, when we think we are more environmentally friendly than others, we actually end up becoming less environmentally friendly.

Logically speaking, the majority of people cannot be more environmentally friendly than the average person.  We are not living in Lake Wobegone where all children are above average.

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The majority consider themselves more environmentally friendly than others

Photo, posted March 6, 2014, courtesy of Karlis Dambrans via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mealworms And Plastic | Earth Wise

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Mealworms are widely cultivated beetle larvae that people feed to pets and to wild birds.  But it turns out, they may have an even more valuable purpose:  they can eat plastic and even plastic containing dangerous chemical additives.

Four years ago, researchers at Stanford discovered that mealworms can actually subsist on a diet of various types of plastic.  They found that microorganisms in the worms’ guts actually biodegrade the plastic.  It might be possible to cultivate the worms using unrecyclable plastic, rather than feeding them grains and fruits.   However, there is the issue of whether it would be safe to feed the plastic-eating worms to other animals, given the possibility that harmful chemicals in plastic additives might accumulate in the worms over time.

Recently, the Stanford researchers studied what happens when the worms ingested Styrofoam or polystyrene.  The plastic commonly used for packaging and insulation typically contains a flame retardant called hexabromocyclododecane, or HBCD.  Studies have shown that HBCD can have significant health and environmental impacts, ranging from endocrine disruption to neurotoxicity.

According to the study, mealworms in the experiment excreted about half of the polystyrene they consumed as tiny, partially degraded fragments and the other half as carbon dioxide.  With it, they excreted the HBCD.  Mealworms fed a steady diet of HBCD-laden polystyrene were as healthy as those eating a normal diet.  And shrimp fed a steady diet of the HBCD-ingesting mealworms also had no ill effects.

It is true that the HBCD excreted by the worms still poses a hazard and must be dealt with in some manner, but mealworms may have a role to play in dealing with unrecyclable plastics like Styrofoam.

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Stanford researchers show that mealworms can safely consume toxic additive-containing plastic

Photo, posted May 11, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)