Monday, April 27, 2020

New tsunami risk identified in Indonesia

by Sarah McDaid, Heriot-Watt University

A team of scientists led by Heriot-Watt University has identified a potential new tsunami risk in Indonesia by mapping below the seabed of the Makassar Strait.

The team says their findings mean that coastal communities currently without tsunami warning systems or mitigation systems could be at risk.

This includes the proposed site of the new Indonesian capital on the island of Borneo.

The researchers used seismic data to map underneath the seafloor of the Makassar Strait, a narrow seaway between the islands of Borneo and Sulawesi.

They found evidence of 19 ancient submarine landslides. Submarine landslides have triggered tsunami waves before, such as the 2018 event on Sulawesi in Indonesia, although most tsunamis are caused by large earthquakes.

Dr. Rachel Brackenridge, now at University of Aberdeen, said: "We found evidence of submarine landslides happening over 2.5million years.

"They happened every 160,000 years or so and ranged greatly in size.

"The largest of the landslides comprised 600 km3 of sediment, while the smallest we identified were five km3.

"There will be many smaller events that we have yet to identify."

Dr. Brackenridge explained how they identified the ancient landslides.

"Seismic data allows us to image the subsurface. The different characteristics of rocks below the seabed allow us to reconstruct the conditions they were deposited in.

"We can see a layered and orderly seabed, then there are huge bodies of sediment that appear chaotic.

"We can tell from the internal characteristics that these sediments have spilled down a slope in a rapid, turbulent manner. It's like an underwater avalanche."

The researchers say that the strong ocean current that flows through the Makassar Strait could be behind the prehistoric events and any potential submarine landslides.

Dr. Uisdean Nicholson, who led the research at Heriot-Watt University, said: "The Makassar Strait is an important oceanic gateway. It's through there the main branch of the Indonesian Throughflow transports water—over 10 million cubic metres a second—from the Pacific to the Indian Ocean.

"The current acts as a conveyor belt, transporting sediment from the Mahakam Delta and dumping it on the upper continental slope to the south, making the seabed steeper, weaker and more likely to collapse.

"We estimate the largest, tsunamigenic events—those that displace 100 km3—occurred every 500,000 years.

"Indonesia has mitigation and early warning measures in place in different parts of the country, but not the area that would be affected by a tsunami wave generated from these landslides.

"This includes the cities of Balikpapan and Samarinda, which have a combined population of over 1.6 million people.

"Such an event could be concentrated and amplified by Balikpapan Bay, the site selected for the new capital city of Indonesia.

"Our next step is to quantify the risk in this area by building various numerical models of landslide events and tsunami generation.

"This could help us predict a threshold size that causes dangerous tsunamis and help inform any mitigation strategies.

"We also plan to visit the coastal areas of Kalimantan to look for physical evidence for historic or prehistoric tsunamis, to test the model outcomes and further improve our understanding of this hazard."

Professor David Tappin of the British Geological Survey and UCL was involved in the study, and is working on the Sulawesi tsunami, which struck the opposite side of the Makassar Strait in September 2018.

Professor Tappin said: "The new study on submarine landslides is important in demonstrating that the tsunami hazard in this region of Indonesia is possibly greater than previously thought, but more research is necessary to confirm this."

Professor Ben Sapiie from Institut Teknologi Bandung, Indonesia, said: "This research enriches the Indonesian geological and geophysical communities' knowledge about sedimentation and landslide hazards in the Makassar Strait. The future of earth sciences research is using an integrated, multi-scientific approach with international collaborators."

Dr. Nicholson recently identified ancient submarine landslides near the Falkland Islands in a separate research project.

Deep-ocean conveyor belt current creates tsunami risk for Falkland Islands

More information: Rachel E. Brackenridge et al. Indonesian Throughflow as a preconditioning mechanism for submarine landslides in the Makassar Strait, Geological Society, London, Special Publications (2020). DOI: 10.1144/SP500-2019-171

Pandemics and pollution: A conversation with an atmospheric scientist

by Robert Perkins, California Institute of Technology

You may have seen the striking before-and-after photos: cities previously blanketed by a dense fog of air pollution now sporting clear skies, as COVID-19 stay-at-home orders bring auto traffic and industry to a halt.

But the issue of improved air quality is not as simple as the photos may suggest, says Caltech's Paul Wennberg, the R. Stanton Avery Professor of Atmospheric Chemistry and Environmental Science and Engineering. Wennberg, an atmospheric chemist and environmental geochemist, studies the influence of human activity on the global atmosphere.

We talked with Wennberg by Zoom to get his take on what we can learn by observing COVID-19's impact on air pollution, and why we are not seeing the same dramatic effects in the Los Angeles area that have been observed elsewhere in the world.

Can you describe the effects on the environment that have been attributed to the COVID-19 stay-at-home orders?

It really depends on where you are. We have seen substantial drops in air-pollution levels as indicated by nitrogen dioxide (NO2) levels, first in China and then in Europe and North America. But there's a lot of nuance in how you interpret those observations because they're very sensitive to things like weather.

For example, Los Angeles had a very rainy period following the start of the stay-at-home orders, and the rain helps clear the air by removing a lot of the soluble pollutants such as aerosols and particles. Linkages between the reduction in emissions and improvements in the air quality are much easier to make in places like India and China than in a place like Los Angeles.

Why is that?

People sometimes don't realize it, but in Los Angeles cars are thought to contribute only a small fraction of the air pollution. Compared to decades past, cars have gotten incredibly clean. We anticipate that the reduction in car traffic reduced the emissions of major pollutants by maybe 10 percent, which is substantial, but pretty small overall. These days, NOx [nitrogen oxide] emissions in Los Angeles come primarily from trucks and other diesel-fueled engines. If you just go out on the highway now, you'll see there are still plenty of trucks.

What about elsewhere in the world?

In other places, the connection between the reduction in traffic associated with COVID-19 and a reduction in air pollution is easier to establish. In Europe, there are far more diesel cars, which emit a lot of NOx. Taking them off of the road has made a much more noticeable impact.

In India, there's been a substantial reduction in electricity demand—a 26 percent drop in just 10 days—so they're turning off coal plants, which also leads to cleaner air. You can contrast that with California, where electricity consumption is down, but not that much. We're down maybe 5 to 10 percent. We're all at home here, but we're still online, using our computers. A lot of the activities that demand electricity just really haven't changed in the way that they would have in a place like India or China, where the manufacturing sector is so dominant.

Will global weather patterns eventually have a homogenizing effect, causing cleaner air everywhere?

To an extent. We anticipate seeing the background levels of ozone in the atmosphere decrease in a more global way, which is a good thing. But a lot of particulate matter doesn't travel far, so the environment's response to this is still going to be pretty localized.

What impact will the changes in air quality have on cloud formation?

Two aspects of this are being tracked. We are interested in quantifying the role of aircraft in producing high-altitude cirrus clouds, which can be found above 16,500 feet and warm the earth. Studies done following 9/11 tried to pin that down using the lack of aircraft in that week following the attack, and these studies suggested that cirrus-cloud creation accounts for perhaps half of the total climate impact of aviation, trapping heat and contributing to global warming.

With the number of flights worldwide decreasing by about two thirds from the end of February to the end of March, we're seeing the 9/11 effect on a global scale. This will be much easier to interpret because it's persisting for a long time, and because it varies by region. For the most part, air travel decreased in China first, and then in Europe, and then in the United States. Presumably the return to aviation will also be heterogeneous, allowing one to try to disentangle the local effects from the effects of the airplanes themselves.

We're also interested in low-altitude clouds, which occur below 6,500 feet. Every cloud droplet has, at its core, a particle that was pre-existing in the atmosphere, so it has been suggested that aerosol pollution has led to changes in cloudiness, and that this has been an important component of climate forcing. Clouds can trap heat, warming the earth. The reduction in aerosol pollution associated with the COVID-19 situation should provide a very, very useful test of those theories which are hard to evaluate in other ways, because effectively both the climate and the pollution story have been co-evolving over 50 years.

What other research opportunities does this represent?

Right before this happened, we had submitted a proposal to the National Science Foundation to study what Los Angeles and the United States would look like, from an air-quality perspective, if we didn't have emitting vehicles anymore. Now we have a better idea based on hard data. As a side project to that proposal, the Resnick Sustainability Institute and the Ronald and Maxine Linde Center for Global Environmental Science commissioned an air-quality station for campus, and it was assembled by one of my staff members, John Crounse [Ph.D. '11], in January and February, just in time to start observing this.

What other tools will be useful for analyzing this?

Right now, we aren't able to get access to a lot of the national science assets that you'd use to track air quality. Normally, you can say, "Let's go take that National Science Foundation airplane and go fly over and have a look and see what's going on." Now, those planes are grounded.

However, we do have a number of remote-sensing instruments, such as the Orbiting Carbon Observatories, OCO-2 and OCO-3. Most of the images that you'll see in the newspaper and on Twitter come from a Dutch instrument called Tropomi, which is a sensor that was launched just a couple of years ago and maps a number of criteria of pollutants, as we call them, from space at pretty high resolution. In addition, there are a couple of other JPL instruments [JPL is managed by Caltech for NASA] that are tracking changes in, for example, carbon monoxide pollution.

Is this going to have a long-term impact, or will air pollution just go back to where it was when the stay-at-home orders lift?

That's actually more of a social than an environmental question. Once you restart the activities that cause air pollution, it'll come roaring back. But there are places that have historically had really bad air pollution and a lot of the population has never really experienced clean air. Suddenly they're experiencing it, and I just can't believe that won't have an effect. People will have seen something different, and I wouldn't be surprised if they will then demand it. We've shown in the U.S. that you can have both good air quality and substantial economic activity. I think people haven't experienced this in a lot of the rest of the world.

What is next?

Springtime weather in Los Angeles is highly variable, making it complicated to interpret the air-quality data we're gathering now. If the stay-at-home orders go on through the summer—and let's hope they don't—we'll have a much better answer to the scientific question of what happens when you reduce car traffic by a factor of two, or three, or four, or whatever we've done.

From a climate-change standpoint, it's as though we've been conducting a centuries-long global experiment by slowly adding more and more carbon dioxide and particulate pollution into the atmosphere. Our knowledge of the impacts of those emissions is challenged by the lack of historical records. But now we've done the reverse—especially for particulate pollution—in a very dramatic and direct way, and at a time when we have better tools to understand it. Seeing how this plays out should be quite a bit more straightforward.Virus lockdown makes big dent in Paris air pollution: report

Are bats to blame for the coronavirus crisis?

by Diana Yates, University of Illinois at Urbana-Champaign

Horseshoe bats in China are a natural wildlife reservoir of SARS-like coronaviruses. Some health experts think wildlife markets—specifically in Wuhan, China—led to the spillover of the new coronavirus into human populations. Though not confirmed, the hypothesis has given bats around the world a bad rap, and public fears of exposure to bats are on the rise. Illinois Natural History Survey wildlife biologist Tara Hohoff, the project coordinator of the Illinois Bat Conservation Program, spoke to News Bureau life sciences editor Diana Yates about bat biology and conservation, and the flying mammals' role in human health.

Are bats a danger to humans?

Generally, no, bats do not endanger people. Bats can be carriers of diseases such as coronaviruses and rabies, but these diseases are not a danger to humans unless people come into contact with bat blood or saliva—a rare occurrence in the U.S. Rabies can be contracted from almost any mammal species, but is commonly reported in bats, raccoons, skunks and foxes. Because bat species are able to withstand and survive infection with many viruses, there is a lot of interest in researching how their immune systems respond to these infections.

What are other common misconceptions about bats?

People tend to believe that bats are like rodents, that all bat species are similar, that they commonly carry dangerous diseases and that they seek to interact with humans—for example, by flying into their hair. But bats are not closely related to rodents and they are an incredibly diverse order of animals. They range from very tiny bumblebee bats that live in caves to large flying foxes. Bat species worldwide eat a wide range of food, including fruit, nectar, insects and fish.

Most bats try to stay as far away from humans as possible, but this is made more challenging as we continue to take away their habitat. Many bat species here in the Midwest prefer to roost in the shaggy bark of dead trees, but as there are fewer trees available, the bats may find their only shelter in people's attics, sheds and garages. This puts them in close proximity to humans where unwanted interactions may occur.

What is the relationship between wildlife markets and the emergence of diseases like the new coronavirus?

Wildlife markets commonly have numerous types of animals that have been harvested from the wild kept in very close proximity to one another. These are animals that would not naturally come into contact with one another. Sometimes live and dead animals are stacked on top of one another, making the transfer of blood or saliva commonplace. People who work in these markets or who purchase animals for the exotic animal trade or for culinary uses are at high risk of exposure to a multitude of diseases.

What is a spillover event? What factors influence whether this occurs?

A spillover event occurs when a pathogen is transferred from its host species to a new species, typically through unnatural contact such as occurs in a wildlife market. The historical host species may have evolved some immunity to the pathogen, while the newly affected species will likely have no natural resistance, making it susceptible to an outbreak.

Some factors that influence the potential for spillover in a wildlife market include the level of infection, sanitary conditions, food preparation methods and the pathogen's compatibility with the newly exposed species. Another interesting factor that influences whether an exposure will turn into an outbreak is how deadly the pathogen is. Diseases that quickly kill their hosts have reduced opportunities to infect new individuals, while less deadly diseases can spread to more individuals.

Is there a solution to this problem?

It is important to reiterate that bats do not choose to interact with humans. We put ourselves at risk when we take animals from the wild and bring them into contact with humans—as occurs, for example, in the Netflix documentary series "Tiger King." We also endanger ourselves when we don't think carefully about how we source animal-derived products, when we destroy habitat, when we live in close proximity to wildlife and when we feed and habituate wildlife to humans. We need to respect wildlife for what it should be, which is wild.

How do bat research and conservation aid human health and society?

Bats are an incredible group of organisms for research because they are so diverse. Their evolution of flight, echolocation (in many species) and adaptations for being nocturnal are all fascinating areas for research. Many species of bats are very long-lived considering their size, so scientists are interested in studying how they age. As mentioned earlier, species such as horseshoe bats have unique immune systems that allow them to survive infectious diseases that are detrimental to other species. We have a lot to learn about how that is possible.

Also, many species of bats perform vital ecosystem services that are useful to human health and economics, such as eating insects, pollinating plants by feeding on nectar and dispersing fruit seeds. For example, researchers at Southern Illinois University estimated that insectivore bat species provide about $1 billion globally in suppression of insects that damage corn crops. Here in Illinois, the suppression of agricultural pests is incredibly important, but we also benefit when local bats consume backyard pests like mosquitoes.Spillover: Why germs jump species from animals to people

Provided by University of Illinois at Urbana-Champaign

Homelessness will worsen due to COVID-19 outbreak—but there are solutions

by Joan Brasher, Vanderbilt University

Eradicating homelessness in America is possible, but it will take "political will," according Vanderbilt University research professor and author Marybeth Shinn.

"The inequality that leads some to live in mansions while others live on the streets is not an inexorable consequence of market forces; it is a consequence of social policies," says Shinn, Cornelius Vanderbilt Professor at Vanderbilt Peabody College of education and human development. "We can choose differently. We can put an end to it."

Despite an abundance of social programs and interventions, large numbers of people continue to live on the streets and in shelters. According to the U.S. Department of Housing and Urban Development, there are more than 550,000 people who are homeless on any given night and far more over the course of a year. These numbers "will likely rise in the wake of the COVID-19 outbreak," she says.

Shinn believes we must address key drivers of homelessness: a lack of affordable housing options; wages that have not kept pace with skyrocketing rent; and discriminatory housing practices. In her new book with Abt Associates researcher Jill Khadduri, "In the Midst of Plenty: Homelessness and What to Do About It" (Wiley-Blackwell 2020), she advocates for long-term subsidies that hold housing costs to 30 percent of income.

"Short term subsidies may be a cheaper and quicker solution, but when they run out, families often end up back in the cycle of homelessness," Shinn says. "Longer-term subsidies not only end homelessness but have radiating benefits for other aspects of family well-being."

The authors advocate for a massive expansion of the Housing Choice Voucher program, with deeper targeting to the neediest households; and robust enforcement of the Affirmatively Furthering Fair Housing mandate.

"Some people will need additional supports," Shinn says. "For people with serious mental illnesses, housing first programs that offer voluntary supportive services without requirements for sobriety or participation in treatment work well. But everyone needs housing."

Especially in times of economic uncertainty, funding and policy changes are needed. But there also must be a change of perception around homelessness in order to end it, Shinn believes.

"Homelessness should not be viewed as a permanent trait or condition. Like unemployment, it's a state that people pass through," she says. "Ultimately, we have the wealth and the knowledge to end homelessness; we need to find the political will. Homelessness is a choice—not a choice by people sleeping on the streets, but a choice by the rest of us to look the other way.

We must act on homelessness before COVID-19 winter

More information: In the Midst of Plenty: Homelessness and What To Do About It. https://www.wiley.com/en-us/In+the+Midst+of+Plenty%3A+Homelessness+and+What+To+Do+About+It-p-9781119

Among the reasons COVID-19 is worse for black communities: Police violence

by Ivan Natividad, University of California - Berkele y

There are various reasons COVID-19 is killing black people at six times the rate of white people, including a lack of access to health care, and poor environmental conditions in black communities.

But one largely unexamined contributor to the disparity, according to a panel of UC Berkeley experts, is the trauma and stress caused by police violence in those communities, and the physical toll of that violence.

"There are levels of chronic stress associated with living in an environment that has more police violence, and the threat of that force on its residents," said Denise Herd, a professor at the School of Public Health who recently examined how that stress can lead to disease in her paper "Cycles of Threat: Graham V. Connor, Police Violence and African American Health Inequities," which will be published in an upcoming issue of the Boston University Law Review.

With the world still in the grips of the pandemic, there is no specific research relating COVID-19 cases to police violence, but Herd said the connection between the chronic stress caused by persistent police-related trauma, and diseases like asthma, diabetes, hypertension and heart disease, which has led to COVID-19 mortality, is clear.

"Those mental health issues often go untreated in African American communities and can lead to diseases that make them more compromised to COVID-19," she added.

Another potentially complicating factor is that asking black people, especially black men, to wear masks, as many public health authorities are requiring, may invite unwarranted attention from police, who have falsely profiled black men as criminals.

"It's a corollary to the 'hoodie' argument from a few years ago, where it is not uncommon for racial minorities wearing hoodies to be considered a threat, while others freely wear them without fear of harassment," said Osagie Obasogie, a Berkeley professor of bioethics.

"Everyday racism continues to be a more immediate concern to communities of color than a pandemic, so some people may decline to wear masks," he added.

"Two Americas, two epidemics'

Herd, who is also associate director of Berkeley's Othering and Belonging Institute, pointed to an array of studies showing black people are more likely to face poor treatment from law enforcement that includes being stopped, injured or even killed by police.

One study, conducted from 2001 to 2014, analyzed 683,000 injuries caused by police that prompted treatment in emergency rooms across the country. The data found that black people were nearly five times more likely to experience police-related injuries than white people, and they also experienced a mortality rate from those injuries twice as high as white patients.

Moreover, Herd said the use of so-called Terry stops, or stop-and-frisk policies, that allow police officers to question, search or detain people they suspect are involved in criminal activity, have been used as a way to hyper-police black communities, creating chronic stress that lowers a person's resistance to disease.

Herd referenced data from the New York Civil Liberties Union that showed between 2004 and 2012, four million Terry stops were conducted predominantly on black and Latino pedestrians. In 2011 alone, 90% of pedestrians stopped were either black or Latino, and 20% of the time police used physical force.

Another study found that men who reported a high number of police stops in their lifetimes were also three times more likely to exhibit post-traumatic stress disorder symptoms and high levels of anxiety and stress.

There isn't just one reason for the health problems in these communities, said Herd. Access to green spaces, affordable housing and other economic factors also play a role. But forms of discrimination and unfair treatment by law enforcement are linked with higher rates of disease in black communities, she said.

In her paper, Herd pointed to research showing that in neighborhoods where pedestrians were more likely to be questioned by police, there was a prevalence of high blood pressure, diabetes, asthma and obesity; health outcomes proven to cause severe COVID-19 symptoms in patients infected with the disease.

"We don't have all the data in yet, but it looks like it's two Americas, two epidemics," said Herd. "In the profile that we saw with affluent white people who had the disease first, it was because of international travel, and the cases tended to be within the older population. I don't think that's going to be true for the African American population. We do also see younger African American people dying."

Wearing a face mask while black

While wearing a face mask in public to stop the spread of COVID-19 may seem like common sense for some, for people of color, particularly black men, wearing or not wearing a mask while out can be a double-edged sword.

Erin Kerrison, an assistant professor at Berkeley's social welfare school who studies how law and legal institutions operate as social determinants of health, said that because of the distrust black people have toward law enforcement, they may not wear masks in public to avoid being viewed as criminals.

"Due to the psychological harm and damage done in those stop-and-frisk encounters, and often the unwarranted harassment, there is a feeling that the police treat them as guilty until proven innocent," Kerrison said,

For example, following the 2012 shooting and killing of Trayvon Martin, a young black teenager walking around his Florida neighborhood, some people said the killing was justified because "he looked shady," Kerrison said.

"What law enforcement views as a public-safety threat is deeply racialized," said Kerrison. "So, it is a common practice for black citizens to limit, if not altogether avoid, any sort of trigger that would lead to an encounter with a police officer."

Study suggests increasing community connection between police and young black men could reduce violent encounters

Provided by University of California - Berkeley

Fins from endangered hammerhead sharks in Hong Kong market traced mainly to Eastern Pacific

by Angela Nicoletti, Florida International University

Credit: Stan Shea

For the first time, researchers have traced the origins of shark fins from the retail market in Hong Kong back to the location where the sharks were first caught. This will allow them to identify "high-risk" supply chains for illegal trade and better enforce international trade regulations.

Marine Scientist Demian Chapman from Florida International University in Miami, led a team based in the United States and Hong Kong—the Special Administrative Region of the People's Republic of China—to conduct DNA analysis on shark fins from scalloped hammerhead sharks (Sphyrna lewini). One of the most common and valuable species in the trade, these sharks face an increasing risk of overexploitation—and possibly extinction.

Many female sharks go "home" to a specific region to give birth. This makes it possible for researchers to identify where a shark was born from the DNA it inherits from its mother. This DNA is present in dried, processed shark fins. The team compared the DNA from fin trimmings collected from dried seafood shops in Hong Kong to a global database of genetic samples collected by scientists from all over the world and were able to determine where the sharks originally came from.

Testing revealed the majority of fins originated from the Eastern Pacific—the coastal strip extending from Baja California to Northern Peru—where vanishing scalloped hammerhead populations are listed as "Endangered" under the U.S. Endangered Species Act. The Eastern Pacific also includes famous island chains like Galapagos and Cocos where tourists go to dive with schools of scalloped hammerheads.

For a species like the scalloped hammerhead, where certain populations in different parts of the world are in severe decline, location information is key for implementing trade restrictions and conducting better fisheries management.

Scalloped hammerhead in Hawaii. Credit: Deron Verbeck

"The shark fin trade is a global market and international trade regulations are part of the solution to better manage threatened species like the scalloped hammerhead" Chapman said. "DNA detective work like this helps us understand which regions in the world are most heavily fishing this species and can narrow down where conservation interventions are needed most."

In 2013, scalloped hammerhead sharks received protection by Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)—an international agreement protecting animals and plants from over-exploitation in international trade. Listed in Appendix II, all trade of these sharks requires permits certifying they were legally caught and traceable through the supply chain.

Shortly afterward, Chapman and the team conducted DNA testing on more than 9,200 shark fin trimmings and found threatened species continue to be found in the Hong Kong retail market. Scalloped hammerheads were the fourth most common out of more than 80 shark species found and the team estimated that around 60% of them came from the Pacific coast of South and Central America.

This study highlights the global nature of the fin trade and emphasizes the need for increased monitoring and better implementation of CITES regulations throughout the world, particularly in the Eastern Pacific. Chapman also points out that the United States plays an important role in intercepting illegal shipments, since many shipments from the Eastern Pacific pass through major U.S. ports before reaching Asia.

The research is supported by the Pew Charitable Trusts, The Pew Fellowship Program and the Roe Foundation. The findings were published this week in Animal Conservation.

Explore further US moves to protect scalloped hammerhead sharks

More information: A. T. Fields et al. DNA Zip‐coding: identifying the source populations supplying the international trade of a critically endangered coastal shark, Animal Conservation (2020). DOI: 10.1111/acv.12585

Provided by Florida International University

Researchers offer glimpse into dinosaur ecosystems
by Jeffrey Renaud, University of Western Ontario

About 75 million years ago, southern Alberta was a lush and warm coastal floodplain rich in plant and animal life, similar to Louisiana’s environment today. Credit: Luke Dickey // Special to Western News

By casting an eye into the daily lives of dinosaurs millions of years in the past, Western researchers may be helping humanity get a glimpse of its future.

Seventy-five-million years ago, North America was divided into western and eastern landmasses by a shallow inland sea. The west was home to an extremely rich diversity of dinosaurs; it has been a mystery as to how so many big animals co-existed in such a small area.

Researchers have proposed that diversity was maintained by dividing up the landscape and food sources. For example, horned dinosaurs (ceratopsians) may have stuck to coastal areas, while duck-billed dinosaurs (hadrosaurs) preferred more inland habitats.

This idea remained untested, however, as researchers cannot directly observe dinosaur behavior and ecosystems.

To solve this conundrum, a team including Western researchers has now compared the compositions of stable isotopes in fossil teeth from these dinosaurs.

Stable isotopes are naturally occurring varieties of chemical elements (like carbon or oxygen) that do not change into other elements over time. When animals consume food and water, the stable isotopes of the elements that make up those resources are passed to the animal's tissues, including tooth enamel.

The stable carbon and oxygen isotope compositions of these herbivorous dinosaurs were measured using various methods. The primary approach was laser gas chromatography isotope ratio mass spectrometry conducted at Western's Laboratory for Stable Isotope Science (LSIS) by Anthropology professor Fred Longstaffe, Western research scientist Li Huang and project lead Thomas Cullen of the Field Museum.

"This approach allowed us to analyze very small samples and, because of that, extend the science of isotope ecology back into the time of the dinosaurs," said Longstaffe, Canada Research Chair in Stable Isotope Science. "Normally, my isotope ecology work is focused on Ice Age animals and the reasons for their disappearance or survival. To attempt to reach back much deeper to the time when the dinosaurs lived was both challenging and exciting."

The study, "Large-scale stable isotope characterization of a Late Cretaceous dinosaur-dominated ecosystem," was recently published in the journal Geology.

The researchers compared results for numerous individuals of each dinosaur species to those of other animals in this ancient ecosystem. While multiple ecological patterns are evident in the results, and differences found in some species, the stable carbon and oxygen isotope ranges for large herbivorous dinosaurs were found to strongly overlap, providing direct evidence against the habitat use hypothesis.

"Measuring the ratios of the different isotopes of elements such as carbon or oxygen in tissues like tooth enamel gives us a unique window into the diet and habitat of an animal who has been extinct for millions of years," Cullen said.

"Dinosaurs lived in a weird world: broad-leafed and flowering plants were much less common; it was warm enough in high latitudes to support crocodilians; carbon dioxide in the atmosphere was higher than it is today; and there was little to no ice at the poles.

"It's not like anything we, as humans, have any direct experience with—but it may be the direction we are headed. It's critical that we understand how ecosystems and environments function under those sorts of conditions so we can better prepare ourselves for the future."

The new study is one of the largest ever conducted on a dinosaur ancient ecosystem, involving more than 350 isotopic measurements from 17 different species whose fossils had all accumulated in a single ancient wetland deposit. Even more uniquely, the authors combined this information with measurements from 16 living species that the team previously sampled from a modern coastal wetland in Louisiana.

About 75 million years ago, southern Alberta was a lush and warm coastal floodplain rich in plant and animal life, similar to Louisiana's environment today.

Explore furtherLate cretaceous dinosaur-dominated ecosystem

More information: T.M. Cullen et al. Large-scale stable isotope characterization of a Late Cretaceous dinosaur-dominated ecosystem, Geology (2020). DOI: 10.1130/G47399.1
Journal information: Geology

New species of turtle discovered

by Senckenberg Research Institute and Natural History Museum

Based on genetic analyses, a second species of mata mata turtle was discovered.

Credit: Rune Midtgaard

Together with an international team, Senckenberg scientist Uwe Fritz described a new species of mata mata turtle based on genetic analyses. Until now, it had been assumed that the genus Chelus only contained a single species. The new description also necessitates a reassessment of the conservation status of these species, which are frequently sold in the illegal animal trade. The study was recently published in the scientific journal Molecular Phylogenetics and Evolution.

There is a good reason for the bizarre appearance of the mata mata turtle: hidden in the mud under water, the up to 53-centimeter-long animals look like algae-covered rocks. But when a prey animal approaches, the turtle sucks it in by suddenly opening its large mouth and swallows it whole. "Although these turtles are widely known due to their bizarre looks and their unusual feeding behavior, surprisingly little is known about their variability and genetics," explains Professor Dr. Uwe Fritz of the Senckenberg Natural History Collections in Dresden, and he continues, "Until now, we assumed that there is only one species of this armored reptile that ranges widely across South America."

But such supposedly widespread species, which are not considered endangered, can be full of surprises—based on genetic analyses, they are often split into two or more independent species. "Several studies have pointed out individual mata mata turtles look differently in the Orinoco River compared to the Amazon Basin. Based on this observation, we decided to take a closer look at these animals' genetic makeup," adds the scientist from Dresden.

The newly described species Chelus orinocensis is found in the Orinoco and Río Negro basins. Credit: Mónica A. Morales-Betancourt

Using 75 DNA samples, the researchers were able to show that, contrary to previous assumptions, there are two genetically and morphologically well-differentiated species of mata mata turtles. The newly described species Chelus orinocensis inhabits the Orinoco and Río Negro basins, while the species known as Chelus fimbriata is restricted exclusively to the Amazon basin.

According to the study, the two species split during the late Miocene, around 13 million years ago. During this period, the former Amazon-Orinoco Basin began separating into the two river basins known today. Numerous aquatic animal species were thus spatially separated and began to diverge genetically.

The description of the new species also necessitates a reassessment of the mata mata's conservation status. "To date, this species was not considered endangered, based on its widespread distribution. However, our results show that, due to the split into two species, the population size of each species is smaller than previously assumed. In addition, every year, thousands of these bizarre-looking animals end up in the illegal animal trade and are confiscated by the authorities. We must protect these fascinating animals before it is too late," adds the study's lead author, Professor Mario Vargas-Ramírez, a former researcher of Senckenberg who now works at the National University of Colombia in Bogotá.

Explore furtherNewly discovered turtle species is facing extinction

More information: Mario Vargas-Ramírez et al. Genomic analyses reveal two species of the matamata (Testudines: Chelidae: Chelus spp.) and clarify their phylogeography, Molecular Phylogenetics and Evolution (2020). DOI: 10.1016/j.ympev.2020.106823

Journal information: Molecular Phylogenetics and Evolution

Provided by Senckenberg Research Institute and Natural History Museum
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Video: The muddle in the middle-Pleistocene
by Wits University

Credit: CC0 Public Domain

During the late middle Pleistocene—between 400 000 and 150 0000 years ago—the populations occupying Earth, and Africa specifically, looked very differently from what they do now. There is evidence for at least three forms of human relatives inhabiting Africa, including Homo heidelbergensis, Homo naledi and Homo sapiens (modern humans).

Some, or all of these hominids made tools such as those associated with the middle stone age culture that began around 305 000 years ago. The question is, which of these human relatives got so crafty? Traditionally, it is thought that the larger brained species like Homo heidelbergensis and Homo sapiens should be associated with more complicated tool kits. But the answers may not be so simple. With three forms of early human relatives around, things are much more complicated, explains Professor Lee Berger.

Fossil skull casts doubt over modern human ancestry

'Dino Cave' reveals dinosaur crouch walkers

by University of Queensland

Old photos from Mount Morgan's sealed off "Dino Cave' have shed light onto new and unusual Aussie dinosaur behaviours, thanks to University of Queensland research.

For a decade, a Mount Morgan cave in central Queensland known for the highest dinosaur track diversity on the entire eastern half of Australia has been closed to the public, restricting research to the site.

Although UQ palaeontologist Dr. Anthony Romilio has had success searching for images of the tracks, he has only recently been provided with new images of different dinosaur's footprints at the site by the Mount Morgan Historical Museum.

"These photographs of fossil footprints have been on museum-display for years," Dr. Romilio said.

"Up until now, it was unknown what type of dinosaurs made these tracks or what the tracks meant.

"A typical dinosaur track of this kind look like those made by birds, but these are shaped like broad-handled forks."

Upon further inspection, Dr. Romilio revealed that the dinosaur must have created the tracks while crouched.

"It's very strange behaviour, and we don't yet know why it did this," Dr. Romilio said.

"You can rule out predatory stalking behaviour, as this set of tracks was made by a two-legged plant eater called an ornithopod.

"And interestingly, this crouching dinosaur was taking bigger steps than other 'normal' walking dinosaurs.

"This unusual posture likely made the prehistoric animal more stable allowing them to quickly cross the muddy shore of an ancient lake."

Dr. Romilio is keen to investigate this mysterious dinosaur despite all of the unknowns.

"There are nine sites in the "Dinosaur Caves' that contain fossil footprints," Dr. Romilio said.

"Where exactly these photos were taken, and when, we just don't know.

"Many of the Mount Morgan track sites were mapped in the early 2000s, although these footprints don't appear on any of them.

"It may be that these fossils had already eroded, making these, and other old photos like them, so incredibly important, as they're our only record of these creature's existence."

The research has been published in Historical Biology.

Solved: The mystery surrounding dinosaur footprints on a cave ceiling

More information: Anthony Romilio. Additional notes on the Mount Morgan dinosaur tracks from the Lower Jurassic (Sinemurian) Razorback beds, Queensland, Australia., Historical Biology (2020). DOI: 10.1080/08912963.2020.1755853

Tomanowos: The meteorite that survived mega-floods and human folly

by Daniel Garcia-Castellanos, The Conversation

Surface detail of the Tomanowos meteorite, showing cavities produced by dissolution of iron. Credit: Eden, Janine and Jim/Wikipedia, CC BY

The rock with arguably the most fascinating story on Earth has an ancient name: Tomanowos. It means "the visitor from heaven" in the extinct language of Oregon's Clackamas Indian tribe.

The Clackamas revered the Tomanowos—also known as the Willamette meteorite – believing it came to unite heaven, earth and water for their people.

Rare extraterrestrial rocks like Tomanowos have a kind of fatal attraction for us humans. When European Americans found the pockmarked, 15-ton rock near the Willamette River more than a century ago, Tomanowos went through a violent uprooting, a series of lawsuits and a period under armed guard. It's one of the strangest rock stories I've come across in my years as a geoscientist. But let me start the tale from its real beginning, billions of years ago.

History of a rock

Tomanowos is a 15-ton meteorite made, as most metal meteorites are, of iron with about 8% nickel mixed in. These iron and nickel atoms were formed at the core of large stars that ended their lives in supernovae explosions.

Those massive explosions spattered outer space with the products of nuclear fusion—raw elements that then ended up in a nebula, or cloud of dust and gas.

Eventually the elements were forced together by gravity, forming the earliest planet-like orbs, or protoplanets of our solar system.

Supernovae disperse the iron produced in heavy stars. Credit: NASA

Some 4.5 billion years ago, Tomanowos was part of the core of one of these protoplanets, where heavier metals like iron and nickel accumulate.

Some time after that, this protoplanet must have collided with another planetary body, sending this meteorite and an unknowable number of other chunks back out into space.

Riding the flood

Subsequent impacts over billions of years eventually pushed Tomanowos' orbit across that of the Earth. As a result of this cosmic billiards game, the Tomanowos meteorite entered Earth's atmosphere around 17,000 years ago and landed on an ice cap in Canada.

Over the following decades, flowing ice slowly transported Tomanowos southwards, towards a glacier in the Fork River of Montana in what is now the United States. This glacier had created a 2,000-foot-high ice dam across the river, impounding the enormous Lake Missoula upstream.

The ice dam crumbled when Tomanowos was nearing it, releasing one of the largest floods ever documented: the Missoula Floods, which shaped the Scablands of Washington State with the power of several thousand Niagara Falls.

Trapped in ice and rafted down river by the flood, Tomanowos crossed modern-day Idaho, Washington and Oregon along the swollen Columbia River at speeds sometimes faster than 40 miles per hour, according to simulations by modern geologists. While floating near what's now the city of Portland, the meteorite's ice case broke apart, and Tomanowos sank to the river bottom.

It is one of hundreds of other "erratic" rocks—rocks made of elements that do not match the local geology—that have been found along the Columbia River. All are souvenirs from the cataclysmic Missoula floods, but none is as rare as Tomanowos.
Geological evidence of the Missoula Flood includes prairie ripple marks and layered silt deposits.

A rock worth suing for

As flood waters ebbed, Tomanowos was exposed to the elements. Over thousands of years, rain mixed with iron sulfide in the meteorite. This produced sulfuric acid that gradually dissolved the exposed side of the rock, creating the cratered surface it bears today.

Several thousand years after the Missoula floods, the Clackamas arrived to Oregon and discovered the meteorite. Did they know it came from the heavens, despite the lack of a crater? The name Tomanowos, or Visitor from the Sky, suggests that they may have suspected the rock's extraterrestrial origins.

Millennia of peaceful rest in the Willamette valley ended in 1902 when an Oregon man named Ellis Hughes secretly moved the iron rock to his own land and claimed it as his property.

Hauling a 15-ton rock on a wooden cart for nearly a mile without being noticed wasn't easy, even in the Wild West. Hughes and his son labored for three back-breaking months. Once the meteorite was on his land, he began charging admission to view the "Willamette Meteorite."

In fact, however, the legitimate owner of the iron rock turned out to be the Oregon Iron and Steel Company, which owned the land where Hughes had found the meteorite and sued for its return. While the suit worked its way through the courts, the company hired a guard who sat atop Tomanowos 24 hours a day with a loaded gun. They won the case in 1905, and sold Tomanowos to the American Museum of Natural History in New York a year later.

Present display of the Tomanowos meteorite, American Museum of Natural History. Credit: Daniel Garcia-Castellanos, CC BY-ND

Floods

Today Tomanowos can be seen in the museum's Hall of the Universe exhibition, which still refers to it as the Willamette Meteorite. In 2000 the museum signed an agreement with descendants of the Clackamas tribe, recognizing the meteorite's spiritual significance to the Native people of Oregon.

The Confederated Tribes of Grand Ronde hold an annual ceremonial visit with the ancient rock that, as their ancestors so aptly observed, brought the sky and the water together here on Earth. In 2019 several fragments of the meteorite that had been held separately were returned to the tribe.

But the museum's written display tells only some of the rock's long story. It omits the Missoula Floods, despite the significance of this event for modern earth science.

Decades after geologists J. Harlen Bretz and Joseph T. Pardee separately posited the theory of the Missoula floods in the early 20th century, their research was used to explain how Tomanowos reached Oregon, where it was found. Their work also triggered one of the most significant paradigm shifts in recent geoscience: the recognition that catastrophic flooding events significantly contribute to the erosion and evolution of landscape

Previously, scientists had followed Lyell's principle of uniformitarianism, which held that Earth's landscape was sculpted by regular, natural processes distributed evenly over long times. Normal floods fit into this theory, but the notion of swift, catastrophic events like the Missoula Floods were somewhat heretic.

The idea of huge Ice Age floods helped geologists a century ago prevail over pre-scientific, religious explanations for unusual finds—such as how marine fossils could be found at high elevation, and how a giant metal rock from outer space came to rest in Oregon.

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Provided by The Conversation

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