Tag Archives: Temperate

Research Suggests Early Primates Thrived in Cold and Temperate Climates

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Textbooks frequently depict primates as having evolved and dispersed exclusively in warm tropical forests, largely based on fossil evidence found in tropical regions. However, a recent study conducted by researchers at the University of Reading indicates that the earliest primates may have thrived in North America’s cold climate, experiencing hot summers and frozen winters.

Primates have transitioned to historically diverse climates: (a) For all primates, transition between the main climates of temperate (top), arid (left), tropical (bottom), and cold (right). The size of the arrows represents the percentage of phylogenetic branches with each transition. (b) Climate transition of early primates living between 650,780,000 years ago. (c) Climate transition of species that lived between 47.8 and 2303 million years ago. (d) Climate transition of species that have lived from 2,303 million years ago to the present. Image credit: Avaria-llautureo et al. , doi: 10.1073/pnas.2423833122.

In this research, Jorge Avalia Lautulo from the University of Reading and his team harnessed statistical modeling alongside fossil data to reconstruct ancient environments and trace where the common ancestors of modern primates existed.

“For decades, the prevailing belief was that primates evolved within warm tropical forests,” stated Dr. Abaria Lautzleo.

“Our findings dramatically overturn this narrative. We discovered that primates did not originate in the lush jungles but in the cold, seasonal environments of the Northern Hemisphere.”

“Understanding how ancient primates adapted to climate change offers insights into how current species might respond to modern shifts in climate and environment.”

Primates, capable of relocating swiftly in response to rapid weather changes, excelled at reproducing, ensuring that offspring survived to establish new species.

As they migrated, primates moved towards entirely different, more stable climates. On average, those remaining in similarly unstable regions were about 561 km apart.

Early primates might have hibernated through the frozen winters, much like today’s bears, sleeping through the coldest months to slow their heart rates and conserve energy.

Some small primates continue this behavior today; for instance, the dwarf lemur in Madagascar digs underground, sleeping for several months during colder periods, shielded from freezing temperatures by layers of roots and leaves.

It wasn’t until millions of years later that primates reached tropical forests.

They began in cold habitats, gradually migrating through temperate zones, arid desert-like areas, and ultimately arriving at today’s hot, humid jungles.

As local temperatures and precipitation fluctuated drastically, primates were compelled to seek new habitats, which facilitated the development of new species.

“Our research indicates that non-tropical, changing environments exerted strong selective pressures on primates with greater dispersal capabilities, encouraging primate diversification and the eventual colonization of tropical climates millions of years post-origination,” the authors concluded.

Their paper was published on August 5th in Proceedings of the National Academy of Sciences.

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Jorge Avalia Rautreo et al. 2025. Radiation and geographical expansion of primates due to diverse climates. PNAS 122 (32): E2423833122; doi: 10.1073/pnas.2423833122

Source: www.sci.news

New fossil discovery suggests that Therapsids originated in the tropics, not temperate regions

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Paleontologists have discovered a new species of early gorgonopsian therapsid that was part of the ancient summer humid biome of equatorial Pangea.

Recreating the life of the Gorgonopsians of Mallorca in a floodplain environment. Image credit: Henry Sutherland Sharpe.

Therapsids were a major component of Permian terrestrial ecosystems around the world, eventually giving rise to mammals in the early Mesozoic Era.

However, little is currently known about when and where it originated.

“Therapsids are a diverse and ecologically successful clade of tetrapods, of which the modern representatives are mammals,” says paleontologist at the Museum of Science and Nature in Barea and the Paleontological Institute of Catalonia. said Dr. Rafel Matamares and colleagues.

“The roots of this clade date back to the late Paleozoic era, when non-mammalian therapsids were important components of terrestrial ecosystems.”

“The oldest distinct therapsids known to date were Laranimus dashankoensisprobably from the Rhodian (Late Middle Permian) deposits of Central East Asia.

“However, phylogenetic analyzes consistently show that therapsids are a sister group to the pterosaur ‘perisaurian’ class monoapsids, which originated in Pennsylvania (about 320 million years ago). It suggests that

“This implies a long lineage of therapsid ghosts spanning about 40 million years.”

The newly discovered therapsid is the oldest of its kind, and possibly the oldest therapsid ever discovered.

This dog-like saber-toothed animal does not yet have a species name, but it belongs to a group of therapsids called gorgonopsids.

“Gorgonopsids are more closely related to mammals than to other modern animals,” said Dr. Ken Angielczyk, a paleontologist at the Field Museum.

“They have no modern descendants and are not our direct ancestors, but they are related to species that were our direct ancestors.”

“The oldest known gorgonopsids lived about 265 million years ago, but the newer fossils date from 270 to 280 million years ago.”

“This is probably the oldest chrysophyte on Earth,” said Dr. Josep Fortuny, a paleontologist at the Miquel Crusafont Catalan Institute of Paleontology.

This fossil was discovered on the Spanish island of Mallorca in the Mediterranean Sea. However, during the time of the Gorgonopsians, Mallorca was part of the supercontinent Pangea.

“The amount of bone remains is surprising,” Dr. Matamares said.

“We found everything from fragments of skulls, vertebrae and ribs to a very well-preserved femur.”

“In fact, when we started this excavation, we did not expect to find so many fossils of this type of animal in Mallorca.”

“If you saw this animal walking down the street, you would think it would look a little like a medium-sized dog, maybe about the size of a husky, but that’s not entirely true,” says Dr. Angielczyk.

“It didn’t have any fur, and it probably didn’t have dog ears.”

“But this is the oldest animal with long, blade-like canine teeth that scientists have ever discovered.”

“These saber-like teeth suggest that this gorgonopsid was the top predator of its time.”

The fact that this gorgonopsian is tens of millions of years older than its closest relatives has changed scientists’ understanding of the evolutionary time of therapsids, key milestones to the emergence of mammals, and, by extension, where we came from. It tells us something about Tanoka.

“Before the age of dinosaurs, there was the age of our ancient mammalian relatives,” Dr. Angielczyk said.

“Most of those ancient mammal relatives looked nothing like what we think of as mammals today.”

“But they were really diverse and had different ecological roles.”

“This new fossil discovery is another piece of the puzzle of how mammals evolved.”

This finding is reported in the following article: paper Published in a magazine nature communications.

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R. Matamares-Andrew others. 2024. Early-Middle Permian Mediterranean gorgonopsids suggest an equatorial origin for therapsids. Nat Commune 15, 10346; doi: 10.1038/s41467-024-54425-5

Source: www.sci.news

Webb captures direct image of a temperate superjupiter orbiting Epsilon Indi A

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Astronomers Webb’s MIRI (Mid-Infrared Instrument) The image was taken of Epsilon Indi Ab, a gas giant several times the mass of Jupiter, located about 12 light years from Earth.

This image of Epsilon Indi Ab was taken with a coronagraph on Webb’s MIRI instrument. Image courtesy NASA / ESA / CSA / Webb / STScI / E. Matthews, Max Planck Institute for Astronomy.

Of the 25 planets that have been directly imaged to date, all are less than 500 million years old, and all but six are less than 100 million years old.

The newly imaged planet orbits Epsilon Indi A (HD 209100, HIP 108870), a K5V type star that is roughly the age of the Sun (3.7 to 5.7 billion years).

“Previous observations of this system have been more indirect measurements of the star, which gave us advance knowledge that there is likely to be a giant planet in the system tugging at the star,” said Dr Caroline Morley, an astronomer at the University of Texas at Austin.

“That’s why our team chose this system as our first observational system at Webb.”

“This discovery is fascinating because the planet is very similar to Jupiter – it’s a little warmer and more massive, but it’s more similar to Jupiter than any other planet imaged so far,” said Dr Elizabeth Matthews, astronomer at the Max Planck Institute for Astronomy.

“The cold planet is very dark and most of its radiation is in the mid-infrared. Webb is ideal for mid-infrared imaging, but it’s very difficult to do from the ground.”

“We also needed good spatial resolution to distinguish planets from stars in the images, and the large Webb mirror helps a lot in this regard.”

Epsilon Indi Ab is one of the coolest exoplanets ever directly detected, with an estimated temperature of 2 degrees Celsius (35 degrees Fahrenheit). This makes it the coolest planet ever imaged outside the solar system, and cooler than all but one free-floating brown dwarf.

The planet is only about 100 degrees Celsius (180 degrees Fahrenheit) warmer than the gas giants in our solar system.

This provides astronomers with a rare opportunity to study the atmospheric composition of a true solar system analogue.

“Astronomers have imagined there could be planets in this system for decades, and fictional planets orbiting Epsilon Indi have been the setting for Star Trek episodes, novels and video games such as Halo,” Dr Morley said.

“It’s exciting to actually see the planet out there and start measuring its properties.”

Epsilon Indi Ab is the 12th closest exoplanet currently known to Earth and the closest planet with a mass greater than Jupiter.

Astronomers chose to study Epsilon Indi A because the system suggested the possibility of planets, using a technique called radial velocity, which measures the back and forth wobble of the host star along the line of sight.

“We expected there to be a planet in this system because the radial velocity suggested its presence, but the planet we found was different to what we expected,” Dr Matthews said.

“It’s about twice as massive, it’s a little farther from its star, and its orbit is different from what we would expect. We don’t yet know what causes this discrepancy.”

“The planet’s atmosphere also seems to differ slightly from what the models predict.”

“So far, only a few atmospheric photometry measurements have been made, making it difficult to draw any conclusions, but the planet is fainter than expected at shorter wavelengths.”

“This could mean that there is a lot of methane, carbon monoxide and carbon dioxide in the planet’s atmosphere, absorbing shorter wavelengths of light. It could also suggest a very cloudy atmosphere.”

a paper The findings were published in the journal. Nature.

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E.C. Matthews othersA temperate superjupiter photographed in mid-infrared by JWST. NaturePublished online July 24, 2024, doi: 10.1038/s41586-024-07837-8

This article has been edited based on the original NASA release.

Source: www.sci.news

Uncovering the Impact of Climate Change on Exoplanets: Transitioning from Temperate to Fear

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Researchers have conducted a new study on the runaway greenhouse effect, revealing how a critical threshold of water vapor could cause catastrophic climate change on Earth and other planets. This study reveals key cloud patterns contributing to this irreversible climate change and provides insight into exoplanets’ climates and their potential to support life. Credit: SciTechDaily.com

The UNIGE team, in collaboration with CNRS, successfully simulated an entire runaway greenhouse effect that could render Earth completely uninhabitable.

Earth is a wonderful blue and green dot covered with oceans and life, Venus It is a yellowish sterile sphere that is not only inhospitable but also sterile. However, the temperature difference between the two is only a few degrees.

A team of astronomers from the University of Geneva (UNIGE) and members of the National Center for Research Competence (NCCR) PlanetS achieved a world first by managing the entire simulation, with support from the CNRS laboratories in Paris and Bordeaux. Achieved. A runaway greenhouse process that could change Earth’s climate from an idyllic environment perfect for life to a harsh and more than hostile place.

Scientists have also demonstrated that from the early stages of the process, atmospheric structure and cloud cover change significantly, making reversing the nearly uncontrollable and runaway greenhouse effect extremely complex. On Earth, an increase in the average temperature of the Earth by a few tens of degrees after a slight increase in the sun’s brightness is enough to start this phenomenon and make our planet habitable.

A runaway greenhouse effect could transform a temperate, habitable planet with oceans of liquid water on its surface into a planet dominated by hot steam hostile to all life. Credit: © Thibaut Roger / UNIGE

Greenhouse effect and runaway scenario

The idea of ​​a runaway greenhouse effect is not new. In this scenario, the planet could evolve from an Earth-like temperate state to a true hell with surface temperatures exceeding her 1000 degrees. Cause? Water vapor is a natural greenhouse gas. Water vapor prevents solar radiation absorbed by the Earth from being re-emitted into space as thermal radiation. It traps some heat like a rescue blanket. A little greenhouse effect would be helpful, but without it, the average temperature of Earth would drop below the freezing point of water, making it a ball of ice and hostile to life.

Conversely, if the greenhouse effect is too strong, it increases evaporation in the oceans and increases the amount of water vapor in the atmosphere. “There is a critical threshold for this amount of water vapor, beyond which the Earth can no longer cool down. From there, everything ramps up until the oceans completely evaporate and temperatures reach hundreds of degrees.” , explains Guillaume Chabelo, a former postdoctoral researcher in the Department of Astronomy at the Faculty of Science at UNIGE and lead author of the study.

Groundbreaking research on climate change

“Other important studies in climatology to date have focused solely on either temperate states before the runaway or habitable states after the runaway,” says a study from the CNRS Institute in Paris and Bordeaux. Martin Tarbet, author and co-author of this paper, explains: study. “This is the first time a research team has used a 3D global climate model to study the transition itself and see how the climate and atmosphere evolve during the process.”

One of the key points of the study explains the emergence of very unique cloud patterns, increasing the runaway effect and making the process irreversible. “From the beginning of the transition, we can observe the development of very dense clouds in the upper atmosphere. In fact, the latter are responsible for the separation of the Earth’s atmosphere and its two main layers, the troposphere and the stratosphere. It no longer exhibits the characteristics of a temperature inversion. The structure of the atmosphere has changed significantly,” points out Guillaume Chavelot.

Serious consequences of searching for life elsewhere

This discovery is an important feature for studying the climate of other planets, especially exoplanets orbiting stars other than the Sun. “By studying the climates of other planets, one of our most powerful motivations is to determine the likelihood of them harboring life,” said Dr. said Emmeline Bolmont, director and co-author of “Extraterrestrial Research” study.

LUC leads cutting-edge interdisciplinary research projects on the origins of life on Earth and the search for life elsewhere in the solar system and beyond planetary systems. “After previous studies, we had already suspected the existence of a water vapor threshold, but the appearance of this cloud pattern is a real surprise!” reveals Emmeline Bolmont. “We also studied in parallel how this cloud pattern produces specific signatures, or ‘fingerprints’, that can be detected when observed. exoplanet atmosphere. The next generation of equipment should be able to detect it, ”he reveals Martin Turbet. The team also doesn’t aim to stop there. Guillaume Chabelo received a research grant to continue this work at the Grenoble Institute for Planetary Observation and Astrophysics (IPAG). This new phase of the research project will focus on specific cases from Earth.

Earth in fragile equilibrium

Using a new climate model, scientists have shown that a very small increase in solar radiation of just a few tens of degrees, leading to a rise in global temperatures, is enough to trigger this irreversible runaway process on Earth. I calculated that. It would make our planet as inhospitable as Venus. One of the current climate goals is to limit global warming caused by greenhouse gases to just 1.5 degrees Celsius by 2050. One of the problems with Guillaume Chavelot’s research grant is to determine whether a small increase in greenhouse gases could cause a runaway process. The brightness of the sun may be enough. If so, the next question becomes determining whether the threshold temperatures for both processes are the same.

Therefore, Earth is not far from this apocalyptic scenario. “Assuming this runaway process begins on Earth, evaporation of just 10 meters of ocean surface would raise atmospheric pressure at the surface by 1 bar. Within just a few hundred years, surface temperatures would exceed 500°C. Then the surface pressure would rise to 273 bar, the temperature would exceed 1500 degrees, and eventually all oceans would completely evaporate,” concludes Guillaume Chavelot.

Reference: “First Exploration of Runaway Greenhouse Transitions Using 3D General Circulation Models” by Guillaume Chaverot, Emeline Bolmont, and Martin Turbet, December 18, 2023. astronomy and astrophysics.

Exoplanets in Geneva: 25 years of expertise wins Nobel Prize

The first exoplanet was discovered in 1995 by two University of Geneva researchers, Michel Mayor and Didier Queloz, who won the 2019 Nobel Prize in Physics. With this discovery, Department of Astronomy, University of Geneva The construction and installation of has put us at the forefront of research in this field. harp upon ESO3.6 meter telescope at La Silla in 2003.

For 20 years, this spectrometer was the world’s most powerful at determining the masses of exoplanets. However, HARPS was surpassed in 2018 by ESPRESSO, another Earth-based spectrometer built in Geneva. very large telescope (VLT) Paranal, Chile.

Switzerland is also working on space-based exoplanet observations with the CHEOPS mission. This is the result of the expertise of two countries. University of Bern, the on-ground experience of the University of Geneva in collaboration with the universities of Geneva and with the support of the universities of the Swiss capital. These two areas of scientific and technical expertise are PlanetS National Center for Research Capability (NCCR).

Life in the Universe Center (LUC): A pillar of interdisciplinary excellence

of Life in the Universe Center (LUC) is an interdisciplinary research center at the University of Geneva (UNIGE), established in 2021 following the 2019 Nobel Prize in Physics awarded to Professors Michel Mayor and Didier Quelot. Thanks to advances over the past decade in both the fields of solar system exploration, exoplanets, and the organic structure of life, it is now possible to address the question of the emergence of life on other planets in a concrete way. Ta. It’s no longer just a guess. Located at the intersection of astronomy, chemistry, physics, biology, and the earth and climate sciences, LUC aims to understand the origin and distribution of life in the universe. Led by the Department of Astronomy, LUC brings together researchers from numerous institutes and departments at UNIGE, as well as from our international partner universities.

Source: scitechdaily.com