Extinction of steam locomotives derails assumptions about biological evolution

The Union Pacific Big Boy Steam Engine (one of the largest steam engines ever built and still functioning) visited Lawrence on Sept. 2, 2021.
Photo Credit: Bruce Lieberman

When the Kinks’ Ray Davies penned the tune “Last of the Steam-Powered Trains,” the vanishing locomotives stood as nostalgic symbols of a simpler English life. But for a paleontologist at the University of Kansas, the replacement of steam-powered trains with diesel and electric engines, as well as cars and trucks, might be a model of how some species in the fossil record died out.

Bruce Lieberman, professor of ecology & evolutionary biology and senior curator of invertebrate paleontology at the KU Biodiversity Institute & Natural History Museum, sought to use steam-engine history to test the merits of “competitive exclusion,” a long-held idea in paleontology that species can drive other species to extinction through competition.

Working with former KU postdoctoral researcher Luke Strotz, now of Northwest University in Xi’an, China, Lieberman found the fossil record largely lacks the detailed data verifying competitive exclusion found in the history of steam engines: “It's really hard to actually see any evidence that competition does play a big role in evolution,” Lieberman said.

Their findings have just been published in the paper “The end of the line: competitive exclusion and the extinction of historical entities2” in the peer-reviewed journal Royal Society Open Science.

Tur­bu­lence: Decades-old the­ory gets a major remake

Ivana Stiperski and the students from the Field Course in Alpine Meteorology setting up the instruments at the “Hochhäuser” i-Box station in the Inn Valley.
Photo Credit: Tobias Posch

Turbulence plays an essential role in weather and climate, and correctly representing its effects in numerical models is crucial for accurate weather forecasts and climate projections. However, the theory describing the effect of turbulence has not changed since its conception in 1950s, despite the fact that it is not representative for the majority of the Earth’s land surface, especially over mountains and polar regions. The Innsbruck meteorologist Ivana Stiperski has now extended the turbulence theory to complex atmospheric conditions. The researcher thus paves the way for the first generalized turbulence theory over complex terrain.

Turbulence is the most important exchange mechanism between the Earth's surface and the overlying atmosphere. However, this mechanism remains one of the last great puzzles of classical physics and mathematics. Ivana Stiperski, head of the research group "Atmospheric Turbulence" at the Department of Atmospheric and Cryospheric Sciences at the University of Innsbruck, has dedicated her work to the study of turbulence over mountains, and since 2020 her team is working on the topic within the framework of an ERC Consolidator Grant. "Turbulence affects phenomena as diverse as climate, storm systems, air pollution and glacier melt. Accurate weather forecasts and climate predictions therefore require a precise description of turbulence, and over the complex terrain of mountainous regions this is particularly difficult as very little is known about how complex terrain modifies turbulence, and no major advance has happened over the past 70 years", Stiperski explains. Until now, the understanding of atmospheric turbulence and how it is included in weather and climate models has been based on the so-called similarity theory, more specifically the "Monin-Obukhov similarity theory " first postulated in 1954. This decades-old theory of turbulence, however, assumes that the Earth’s surface is flat and horizontally homogeneous (i.e., has uniform characteristics in the horizontal, such as for example infinite grasslands or corn fields), and therefore it is not representative for the majority of the Earth’s land surface. This incorrect representation of turbulence adds uncertainty to weather prediction and climate projections.

Earth’s first plants likely to have been branched, study finds

Selaginella
Photo Credit: Vicky Spencer

A new discovery by scientists at the University of Bristol changes ideas about the origin of branching in plants.

By studying the mechanisms responsible for branching, the team have determined what the first land plants are likely to have looked like millions of years ago. 

Despite fundamentally different patterns in growth, their research has identified a common mechanism for branching in vascular plants.

Dr Jill Harrison from Bristol’s School of Biological Sciences explained: “Diverse shapes abound in the dominant flowering plant group, and gardeners will be familiar with ‘pinching out’ plants’ shoot tips to stimulate side branch growth, leading to a bushier overall form.

“However, unlike flowering plants, other vascular plants branch by splitting the shoot apex into two during growth, a process known as ‘dichotomy’.

As an ancient vascular plant lineage that formed coal seams during the Carboniferous era, lycophytes preserve the ancestral pattern of dichotomous branching.

Surprise effect: Methane cools even as it heats

Annual mean near-surface air temperature response to methane, decomposed into (a) longwave and shortwave effects; (b) longwave effects only; and (c) shortwave effects only.
Full size Image
Illustration Credit: Robert Allen / University of California, Riverside

Most climate models do not yet account for a new UC Riverside discovery: methane traps a great deal of heat in Earth’s atmosphere, but also creates cooling clouds that offset 30% of the heat. 

Greenhouse gases like methane create a kind of blanket in the atmosphere, trapping heat from Earth’s surface, called longwave energy, and preventing it from radiating out into space. This makes the planet hotter. 

“A blanket doesn’t create heat, unless it’s electric. You feel warm because the blanket inhibits your body’s ability to send its heat into the air. This is the same concept,” explained Robert Allen, UCR assistant professor of Earth sciences.

In addition to absorbing longwave energy, it turns out methane also absorbs incoming energy from the sun, known as shortwave energy. “This should warm the planet,” said Allen, who led the research project. “But counterintuitively, the shortwave absorption encourages changes in clouds that have a slight cooling effect.”

Mapping Migration

Avian research often focuses on forests as breeding habitats, but scientists are now working to understand the vital role that small forest patches play in migration. For the first time, a team of researchers from Princeton University and the University of Delaware has created a comprehensive map of migratory pathways and stopover locations in the Eastern United States.
Illustration Credit: Jeffrey C. Chase

Researchers release first comprehensive map of migratory bird patterns in Eastern U.S.

When the song pauses in a game of musical chairs, everyone jostles for one of the remaining seats. Bird migration today is much the same. When it’s time for a break in their biannual travels, songbirds descend to rest and refuel, searching for respite in a dwindling number of forest patches.

Avian research often focuses on forests as breeding habitats, but scientists are working to understand the role that small forest patches play in migration — a vital portion of a bird’s lifecycle when you consider that some species spend as much as half the year in transit. Now, for the first time, a team of researchers from Princeton University and the University of Delaware has created a comprehensive map of migratory pathways and stopover locations in the Eastern United States.

“Small pockets of deciduous forest are often neglected in conservation planning because birds have low breeding success in these spaces,” said Princeton University doctoral candidate Fengyi Guo, lead author of the study. “But the entire population moves across the continent twice annually. Many of them depend on food and shelter in these forest pockets to complete their migration and a chain is only as strong as its weakest link. Successful conservation of migratory bird populations requires enough habitat to be protected at all stages of its annual cycle.”

Parasites alter likelihood of fish being caught by anglers

Itsuro Koizumi (second from left) and Ryota Hasegawa (first from right), authors of the paper, with Taro Matsuda of Setsunan University (center), and Masashiro Naka (first from left) and Chiharu Furusawa (second from right) of the Koizumi lab
Photo Credit: Itsuro Koizumi

Parasitic infections in salmonid fish can increase or decrease their vulnerability to angling, depending on their body condition.

Angling, a type of fishing, is a popular pastime across the world, and is known to be 40,000 years old. Angling usually takes place in natural bodies of water, which may have populations of wild fish, or be stocked with cultured fish. Fish caught by angling may either be consumed, or may be immediately released.

Parasites are very common in nature, found everywhere that their hosts are found. Parasites are known to alter the susceptibility of fish to predators. Angling can be considered predation of fish; however, there has been almost no in-depth research on how parasites affect the susceptibility of fish to angling.

Associate Professor Itsuro Koizumi at the Faculty of Environmental Earth Science, Hokkaido University, and graduate student Ryota Hasegawa have investigated how a mouth and gill parasite of the whitespotted char, a salmonid fish, affects its vulnerability to angling. Their findings were published in the journal The Science of Nature.

New Study Provides First Comprehensive Look at Oxygen Loss on Coral Reefs

Coral reefs at a study site off Taiping Island, South China Sea.
Photo Credit: Yi Bei Liang

Scripps Oceanography scientists and collaborators provide first-of-its-kind assessment of hypoxia, or low oxygen levels, across 32 coral reef sites around the world

A new study is providing an unprecedented examination of oxygen loss on coral reefs around the globe under ocean warming. Led by researchers at UC San Diego’s Scripps Institution of Oceanography and a large team of national and international colleagues, the study captures the current state of hypoxia—or low oxygen levels—at 32 different sites, and reveals that hypoxia is already pervasive on many reefs.

The overall decline of oxygen content across the world’s oceans and coastal waters—a process known as ocean deoxygenation—has been well documented, but hypoxia on coral reefs has been relatively underexplored. Oxygen loss in the ocean is predicted to threaten marine ecosystems globally, though more research is needed to better understand the biological impacts on tropical corals and coral reefs.

The study, published March 16 in the journal Nature Climate Change, is the first to document oxygen conditions on coral reef ecosystems at this scale.

Climate change creates ‘win-win’ between bald eagles and farmers

Bald eagle
Photo Credit: Brian E. Kushner/Lab of Ornithology 

As they seek new foods because climate change has altered their traditional diet of salmon carcasses, bald eagles in northwestern Washington state have become a boon to dairy farmers, deterring pests and removing animal carcasses from their farms, a new study finds.

The mutually beneficial relationship is described in “A Win-Win Between Farmers and an Apex Predator: Investigating the Relationship Between Bald Eagles and Dairy Farms,” which published March 10 in the journal Ecosphere.

“The narrative around birds of prey and farmers has traditionally been negative and combative, mainly due to claims of livestock predation,” said lead author Ethan Duvall, a doctoral student in ecology and evolutionary biology. “However, dairy farmers in northwestern Washington do not consider the eagles threats. In fact, many farmers appreciate the services that the eagles provide such as carcass removal and pest-deterrence.”

QUT rock stars solve long-standing diamond conundrum

Professor Balz Kamber and Carl Walsh
Photo Credit: Courtesy of Queensland University of Technology

Two QUT researchers have used a standard laptop computer and a humble piece of rock - from the ‘waste pile’ of a diamond mine - to solve a long-held geological conundrum about how diamonds formed in the deep roots of the earth’s ancient continents.

The paper Deep, ultra-hot-melting residues as cradles of mantle diamond has been published in the prestigious academic journal Nature by lead author QUT PhD student Carl Walsh, along with QUT Professor Balz Kamber and Emma Tomlinson from Trinity College, Ireland.

Mr. Walsh said the study, for his MSc research, involved computer modelling on a rock from the African continent and recovered from the bottom of the lithosphere, the outer part of the Earth between about 30km and 250km below the surface.

Mr. Walsh said the dominant part of a continent was the part that you never see. 

“If you think of an iceberg – the visible part – if you just had an iceberg floating on the ocean surface it would tip over like a boat. This is like the keel of an iceberg,” Mr. Walsh said.

“Denoising” a Noisy Ocean

Study lead author Ella Kim (pink helmet) helps deploy a HARP instrument package.
Photo Credit: Ana Širović

Come mating season, fishes off the California coast sing songs of love in the evenings and before sunrise. They vocalize not so much as lone crooners but in choruses, in some cases loud enough to be heard from land. It’s a technique of romance shared by frogs, insects, whales, and other animals when the time is right.

For most of these vocal arrangements, the choruses are low-frequency. They’re hard to distinguish from the sounds of ships passing in the night among others.

Biologists, however, have long been interested in listening in on them in the name of understanding fish behavior toward an ultimate goal: They can help preserve fish populations and ocean health by identifying spawning seasons to inform fisheries management.

Now scientists at Scripps Institution of Oceanography at UC San Diego and colleagues have developed a way for computers to sift through sounds collected by field acoustic recording packages known as HARPs and process them faster than even the most trained human analysts. The method represents a major advance in the field of signal processing with uses beyond marine environments.

Extinction vulnerability during ancient biodiversity crises is unpredictable

Jurassic marine fossils
Photo Credit: Dr James Witt

Evidence from past extinctions cannot be used as a definitive way of predicting future biodiversity loss, scientists have found by using AI.

A team of researchers including Dr James Witts of the University of Bristol’s School of Earth Sciences and led by Dr William Foster from Hamburg University used fossils from previous mass extinctions to see if AI-generated models can accurately predict extinction vulnerability.

Despite expectations, this research found that mass extinctions could not be used to generate predictive models for other biodiversity crises, with no common cause flagged. This is because marine communities are constantly evolving and no two mass extinctions are impacting the same marine ecosystem.

Co-author Dr Witts explained: “In a time of increasing extinction risk, knowing whether we can make predictions about the vulnerabilities of different organisms to extinction is essential.”

Dr Foster continued: “The scale of environmental change currently affecting our planet is unprecedented in human history, and so the best source of evidence we have for comparable environmental change lies in the deep past, accessible via analysis of the fossil record.

Why are mammals more likely to go extinct on islands than on the mainland?

Illustration of Sardinian Dwarf Mammoth, Sardinian Giant Otter, Deer, Sardinian Dhole and Giant Pica
 Illustration Credit: Peter Schouten

Islands are "laboratories of evolution" and home to animal species with many unique features, including dwarfs that evolved to very small sizes compared to their mainland relatives, and giants that evolved to large sizes. A team of researchers from the German Centre of Integrative Biodiversity Research (iDiv) and Martin Luther University Halle-Wittenberg (MLU) has now found that species that evolved to more extreme body sizes compared to their mainland relatives have a higher risk of extinction than those that evolved to less extreme sizes. Their study, which was published in Science, also shows that extinction rates of mammals on islands worldwide increased significantly after the arrival of modern humans.

Islands are hotspots for biodiversity - they cover less than 7% of the Earth’s land area, but account for up to 20% of all terrestrial species on the planet. However, islands are also hotspots for species extinction as 50% of today’s IUCN threatened species are native to islands. 

A pool at Yellowstone is a thumping thermometer

The interval of thumps at Doublet Pool offers insight into the fluctuations of energy in the Yellowstone hydrothermal system.
Photo Credit: Jacob W. Frank / U.S. National Park Service

While the crowds swarm around Old Faithful to wait for its next eruption, a little pool just north of Yellowstone National Park’s most famous geyser is quietly showing off its own unique activity, also at more-or-less regular showtimes. Instead of erupting in a towering geyser, though, Doublet Pool cranks up the bass every 20 to 30 minutes by thumping. The water vibrates and the ground shakes.

Doublet Pool’s regular thumping is more than just an interesting tourist attraction. A new study led by University of Utah researchers shows that the interval between episodes of thumping reflects the amount of energy heating the pool at the bottom, as well as in indication of how much heat is being lost through the surface. Doublet Pool, the authors found, is Yellowstone’s thumping thermometer.

“By studying Doublet Pool, we are hoping to gain knowledge on the dynamic hydrothermal processes that can potentially be applied to understand what controls geyser eruptions,” said Fan-Chi Lin, an associate professor in the department of geology and geophysics at the U and a study co-author, “and also less predictable and more hazardous hydrothermal explosions.”

The study is published in Geophysical Research Letters.

Pioneering study shows flood risks can still be considerably reduced if all global promises to cut carbon emissions are kept

Maps show historical expected annual flood damage (EAD) in GBP billion at 2020 values, and calculated EAD percentage increase with 1.8 degrees global warming.
Illustration Credit: University of Bristol and Fathom

Annual damage caused by flooding in the UK could increase by more than a fifth over the next century due to climate change unless all international pledges to reduce carbon emissions are met, according to new research.

The study, led by the University of Bristol and global water risk modelling leader Fathom, reveals the first-ever dataset to assess flood hazard using the most recent Met Office climate projections which factor in the likely impact of climate change.

Its findings show the forecasted annual increase in national direct flood losses, defined as physical damage to property and businesses, due to climate change in the UK can be kept below 5% above recent historical levels. But this is only on the proviso that all countries fulfil the ambitious pledges they signed up to at COP26 and also that countries, including the UK, which made further Net Zero commitments, actually achieve these on time and in full.

Red Deer Natural Habitat Recreated Over the Past 50,000 Years

During the period of global cooling (33,000 years ago), the range of the species declined and reached a minimum of around
Photo Credit: Alexis B

The natural habitat of the European Red deer over the last 50,000 years has been recreated and described by a team of scientists from Russia, Poland, Ukraine, the UK and Italy. An article summarizing the research has been published in The Journal of Archaeological Science.

The details of how reindeer ecology changed with climate warming during the Pleistocene to Holocene transition allow an assessment of the species' adaptive capacity. As reindeer have been widespread in Europe for tens of thousands of years, the data can be used for the study of human life and diet in this part of the world since the Late Pleistocene.

"At the beginning of the study period, the European Red deer tended to feed on plants inherent to open landscapes such as tundra, steppe, and meadows. During this stage, particularly with the maximum cold snap, 26-19 thousand years ago, the Red deer, as well as their ungulate neighbors (the reindeer and horses), were affected by prolonged low temperatures and lack of nutrients. The exception included some territories of modern Spain and Italy," says Pavel Kosintsev, Head Specialist of the UrFU Laboratory of Natural Science Methods in Humanities, Senior Researcher of the Institute of Plant and Animal Ecology of the Russian Academy of Sciences (Ural Branch), and co-author of the article.

Climate change raises the threat of multiple hurricanes

Princeton researchers explored the increasing risk of multiple destructive storms hitting locations on the Atlantic and Gulf coasts. In this image, three storms formed in the Atlantic basin in 2017. 
Photo Credit: NASA

Getting hit with one hurricane is bad enough, but new research from Princeton Engineering shows that back-to-back versions may become common for many areas in coming decades.

Driven by a combination of rising sea levels and climate change, destructive hurricanes and tropical storms could become far more likely to hit coastal areas in quick succession, researchers found. In an article published Feb. 27 in the journal Nature Climate Change, the researchers said that in some areas, like the Gulf Coast, such double hits could occur as frequently as once every three years.

“Rising sea levels and climate change make sequential damaging hurricanes more likely as the century progresses,” said Dazhi Xi, a postdoctoral researcher and a former graduate student in civil and environmental engineering and the paper’s lead author. “Today’s extremely rare events will become far more frequent.”

Could Space Dust Help Protect the Earth from Climate Change?

Illustration Credit: Ben Bromley/University of Utah

On a cold winter day, the warmth of the Sun is welcome. Yet as humanity emits more greenhouse gases, the Earth's atmosphere traps more and more of the Sun's energy, which steadily increases the Earth's temperature. One strategy for reversing this trend is to intercept a fraction of sunlight before it reaches our planet.

For decades, scientists have considered using screens or other objects to block just enough of the Sun’s radiation — between 1 or 2 percent — to mitigate the effects of global warming. Now, a new study led by scientists at the Center for Astrophysics | Harvard & Smithsonian and the University of Utah explores the potential of using dust to shield sunlight.

The paper, published today in the journal PLOS Climate, describes different properties of dust particles, quantities of dust and the orbits that would be best suited for shading Earth. The team found that launching dust from Earth to a way station at the "Lagrange Point" between Earth and the Sun would be most effective but would require an astronomical cost and effort.

The team proposes moondust as an alternative, arguing that lunar dust launched from the Moon could be a low-cost and effective way to shade the Earth.

Climate Trends in the West, Today and 11,000 Years Ago

UC Davis students hike in the Grand Canyon, a landscape that has changed dramatically over the past thousands and millions of years.
Photo Credit: Joe Proudman/UC Davis

People often say things like Phoenix has always been dry; Seattle has always been wet; and San Francisco has always been foggy. But “always” is a strong word. 

A study from the University of California, Davis, synthesizes climate trends across the Western U.S. during a relatively young period of Earth’s history — the Holocene Era, which stretches from the present day to the past 11,000 years. This look at the really Old West shows that the hallmarks of California’s climate — the foggy coastlines that gave rise to towering redwoods, the ocean upwelling that spawned productive fisheries, the warm summers and mild winters — began around 4,000 years ago. 

It also reveals a time when the Pacific Northwest was warm and dry and the Southwest was warm and wet.

Mysteries of the Earth: FSU researchers predict how fast ancient magma ocean solidified

An illustration of Earth as it existed during part of its formation billions of years ago, when an ocean of magma covered the surface of the planet and stretched thousands of miles deep into the core. A typical cell from a simulation conducted by FSU researchers with the relative positions of atoms are shown in the left
Illustration Credit: Courtesy of Suraj Bajgain / Lake Superior State University

Early in the formation of Earth, an ocean of magma covered the planet’s surface and stretched thousands of miles deep into its core. The rate at which that “magma ocean” cooled affected the formation of the distinct layering within the Earth and the chemical makeup of those layers.

Previous research estimated that it took hundreds of million years for that magma ocean to solidify, but new research from Florida State University published in Nature Communications narrows these large uncertainties down to less than just a couple of million years.

“This magma ocean has been an important part of Earth’s history, and this study helps us answer some fundamental questions about the planet,” said Mainak Mookherjee, an associate professor of geology in the Department of Earth, Ocean and Atmospheric Science.

When magma cools, it forms crystals. Where those crystals end up depends on how viscous the magma is and the relative density of the crystals. Crystals that are denser are likely to sink and thus change the composition of the remaining magma. The rate at which magma solidifies depends on how viscous it is. Less viscous magma will lead to faster cooling, whereas a magma ocean with thicker consistency will take a longer time to cool.

London falcons ate fewer pigeons during lockdowns

Peregrine falcon
Photo Credit: Jasmin777

The study by King’s researchers suggests that predatory birds in urban spaces are vulnerable to changes in human activities that support prey populations.

Changes in peregrine falcon diets during COVID-19 lockdowns highlight the impact of human behavior on urban predators. The findings are from a new study co-authored by King’s researchers published in the British Ecological Society journal, People and Nature.

Researchers from King’s College London and University of Bristol found that during lockdowns, peregrine falcons in London were forced to change their diet away from pigeons since fewer of these birds were being drawn in by human food supplies such as discarded food waste or direct feeding.

Brandon Mak, a PhD student in the Department of Geography who co-led the study with Ed Drewitt from the University of Bristol, said: “Our results indicate that peregrines in larger, highly urbanized cities like London may be more dependent on, and hence more vulnerable to changes in, human activities which support their prey populations, particularly feral pigeons.”