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Readers’ wildlife photos

Why Evolution is True Feed - Fri, 01/03/2025 - 6:15am

We have photos from a new contributor, reader Lesli Sagan. She keeps bees and sends us photos of honeybees.  Lesli’s notes are indented, and you can enlarge her photos by clicking on them.

All of these photos were taken in Ithaca, NY this past summer and fall, 2024. I’ve been keeping bees for decades and tend to garden for them: asters, oregano, mountain mint, coneflowers, and anything else I think they would like are my garden favorites. There’s some question in my mind whether European honey bees (Apis mellifera) are truly “wild,” given that we’ve selectively bred them. However, they are free to go anytime and often do return to the wild by absconding or swarming.

Unused bee equipment is attractive to all sorts of critters, including honey bees who may either be looking for a new home or are attracted, during lean times, to the scent of honey.

These are bees emerging through an opening in the cover of their hive.

Asters bloom until the first hard frost, and so are valuable sources of nectar and pollen for honey bees and all sorts of other insects.

This closer look of a honey bee shows her body is still fuzzy and her wings are whole. Honey bees live about a month in summer and they can be nearly bald and their wings quite ragged towards the end of the lives. This bee is probably a couple of weeks old.

While this bee is likely going for the nectar, we can still see yellow pollen on her face.

In contrast to the young bee above, this old girl has lost much of her fuzziness and her wings have been literally flown to bits. Mountain mint is a favorite of all sorts of bees.

The top bee on mountain mint is Apis mellifera, and the bee below may be as well. Not all domesticated honey bees are the familiar gold and black; darker varieties exist. None of my hives have the darker variety, so if this is Apis mellifera, she’s not from my hives.

This is an unremarkable scene at a hive entrance. Bees are coming and going, and while a few are likely guards, there are no hornets or other predators trying to break in just now.

Another fuzzy young bee, this time on oregano. She is collecting pollen, as you can see from the white pollen ball on her back leg. Pollen colors don’t always match the color of the flowers, but in this case, the petals and pollen are bright white.

This hive has windows, and here you can see the worker bees preparing cells for the honey flow.

If anyone wants to watch a complete hive inspection from this past summer, here’s a link to a GoPro video.

Categories: Science

US teens are using less of every substance – except for one

New Scientist Feed - Fri, 01/03/2025 - 5:00am
Teenagers in the US roughly doubled their use of nicotine pouches in 2024, despite turning away from alcohol and other drugs
Categories: Science

Glowing biological quantum sensor could track how cells form

New Scientist Feed - Fri, 01/03/2025 - 1:00am
A quantum sensor based on a protein from bioluminescent jellyfish can be made by the body itself and it may be able to help us track how cells form or detect disease at an early stage
Categories: Science

NASA Scientists Discover “Dark Comets” Come in Two Populations.

Universe Today Feed - Thu, 01/02/2025 - 7:05pm

On October 19th, 2017, the Panoramic Survey Telescope and Rapid Response System-1 (Pan-STARRS-1) in Hawaii announced the first-ever detection of an interstellar object, named 1I/2017 U1 ‘Oumuamua (the Hawaiin word for “scout”). This object created no shortage of confusion since it appeared as an asteroid but behaved like a comet (based on the way it accelerated out of the Solar System). Since then, scientists have noticed a lot of other objects that behave the same way, known as “dark comets.”

These objects are defined as “small bodies with no detected coma that have significant nongravitational accelerations explainable by outgassing of volatiles,” much like ‘Oumuamua. In a recent NASA-supported study, a team of researchers identified seven more of these objects in the Solar System, doubling the number of known dark comets. Even more important, the researchers were able to discern two distinct populations. They consist of larger objects that reside in the outer Solar System and smaller ones in the inner Solar System.

The study was led by Darryl Z. Seligman, an NSF Astronomy and Astrophysics Postdoctoral Fellow from the Carl Sagan Institute at Cornell University and Michigan State University. He was joined by researchers from the European Space Agency’s Near-Earth Object Coordination Centre (NEOCC), the European Southern Observatory (ESO), the Planetary Science Institute (PSI), Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder, NASA’s Jet Propulsion Laboratory. Their findings were published on December 9th in the Proceedings of the National Academy of Sciences (PNAS).

Astronomers are discovering more objects that look like asteroids but behave like comets. Credit: N. Bartmann (ESA/Webb), ESO/M. Kornmesser and S. Brunier, N. Risinger (skysurvey.org)

Scientists got their hint that dark comets exist in 2016 when they found that the “asteroid” 2003 RM had deviated slightly from its expected orbit. This behavior could not be explained by the Yarkovsky effect, where asteroids absorb solar energy and re-radiate it into space as heat. Said study co-author Davide Farnocchia of NASA JPL said in a NASA press release:

“When you see that kind of perturbation on a celestial object, it usually means it’s a comet, with volatile material outgassing from its surface giving it a little thrust. But try as we might, we couldn’t find any signs of a comet’s tail. It looked like any other asteroid — just a pinpoint of light. So, for a short while, we had this one weird celestial object that we couldn’t fully figure out.”

The next piece of the puzzle came in 2017 with the detection of the first interstellar object (‘Oumuamua). While it appeared as a single point of light to telescopes and had no coma, its trajectory changed as if it were outgassing volatile material from its surface. “‘Oumuamua was surprising in several ways,” said Farnocchia. “The fact that the first object we discovered from interstellar space exhibited similar behaviors to 2003 RM made 2003 RM even more intriguing.”

By 2023, seven dark comets had been identified, leading the astronomical community to designate them as a distinct category of celestial objects. With this latest study, the authors identified seven more of these objects in the Solar System and noticed some interesting traits among them. “We had a big enough number of dark comets that we could begin asking if there was anything that would differentiate them,” said Seligman. “By analyzing the reflectivity,” or albedo, “and the orbits, we found that our solar system contains two different types of dark comets.”

Artist’s impression of the interstellar object, `Oumuamua, experiencing outgassing as it leaves our Solar System. Credit: ESA/Hubble, NASA, ESO, M. Kornmesser

One group, which the team calls “outer dark comets,” is similar to the “families” of asteroids that orbit Jupiter. In addition to being larger, measuring hundreds of meters or more across, the first group has highly elliptical orbits. The second group, “inner dark comets,” are smaller (tens of meters or less) and travel in nearly circular orbits within the orbits of Mercury, Venus, Earth, and Mars. In addition to expanding astronomer’s knowledge of dark comets, the team’s research raises several additional questions regarding their origin, behavior, and composition.

Of particular interest is whether these objects could contain water ice, which would have implications for our understanding of how water (and possibly life) was distributed throughout the Solar System billions of years ago. “Dark comets are a new potential source for having delivered the materials to Earth that were necessary for the development of life,” said Seligman. “The more we can learn about them, the better we can understand their role in our planet’s origin.”

Further Reading: NASA, PNAS

The post NASA Scientists Discover “Dark Comets” Come in Two Populations. appeared first on Universe Today.

Categories: Science

Could There Be Bacteria Living on Mars Today?

Universe Today Feed - Thu, 01/02/2025 - 3:23pm

Mars is often considered to be the planet most similar to the Earth. Earth however, is capable of supporting life, Mars on the other hand could not. There was once a time when it was warmer and wetter and could support life. Exploring life on Earth shows us that bacteria known as extremophiles can live in the most harsh conditions on Earth, it may just be possible that there are places on Mars that could also support these hardy forms of life. A new paper explores that possibility by studying the most extreme Earth-based bacteria that could survive under ground on Mars. 

Mars, often referred to as the “Red Planet” because of its reddish appearance. It’s the fourth planet from the Sun orbiting at an average distance of 228 million kilometres. It has a thin atmosphere, made up mostly of carbon dioxide with surface temperatures from about -125°C to 20°C. Mars has some fascinating geological features including the largest volcano in the solar system; Olympus Mons, and a vast canyon system; Valles Marineris. Unlike Earth, Mars has two moons Phobos and Deimos which are thought to be captured asteroids. 

A full-disk view of Mars, courtesy of VMC. Credit: ESA

The atmosphere of Mars is thin and, whilst carbon dioxide is the main component, there is also methane in small amounts, around 0.00003% of the whole. It’s origins in the Martian atmosphere are not fully understood and it may be that it is there as a result of biological processes such as the metabolism of microbes. It could also be there due to geological processes such as volcanic eruptions. The presence of methane has also excited researchers who have been exploring whether Mars could in anyway support more extreme forms of primitive life. 

Image of the Martian atmosphere and surface obtained by the Viking 1 orbiter in June 1976. (Credit: NASA/Viking 1)

In a paper recently authored by Butturini A from the University of Barcelona and team, they explore the Martian environment and its suitability to support extremophiles known as methanogens (from the Methanobacteriaceae family.) These primitive forms of bacteria are found in some of the most inhospitable regions of Earth. They have been found thriving in the hot groundwater of Lidy Hot Springs in Idaho, and are based upon methane biology. It raises an interesting possibility that areas of Mars could provide a habitat for them. 

The conditions on the surface of Mars are well understood. With high energy radiation from cosmic rays and solar radiation, along with dry and cold conditions and a high temperature differential between day and night, the surface is not conducive to any known forms of life. Look a little deeper however and the conditions seem a little more favourable. Lower levels on Mars however may be more habitable than the surface. A few metres underground and the surface material offers protection from the incoming radiation. Temperatures lower down would be higher and less variable too giving the possibility that liquid water may be present. It has already been seen that subsurface water has in some areas of Mars found its way to the surface only to evaporate when met with the surface conditions. With the presence of salt too the subsurface water can be present as liquid at a lower temperature. 

The team conclude that methanogens seem to be thriving in hostile environments on Earth which are analogous to some areas of Mars. They identify the southern area of Acidalia Planitia as somewhere to search due to the high levels of radiogenic heat producing elements which suggest subsurface water may be present. It raises the interesting possibility that, theoretically at least, primitive life could exist on Mars, even today, we just need to find it!

Source:  Potential habitability of present-day Mars subsurface for terrestrial-like methanogens

The post Could There Be Bacteria Living on Mars Today? appeared first on Universe Today.

Categories: Science

AI can improve ovarian cancer diagnoses

Computers and Math from Science Daily Feed - Thu, 01/02/2025 - 1:26pm
A new international study shows that AI-based models can outperform human experts at identifying ovarian cancer in ultrasound images.
Categories: Science

How good are AI doctors at medical conversations?

Computers and Math from Science Daily Feed - Thu, 01/02/2025 - 1:26pm
Researchers design a new way to more reliably evaluate AI models' ability to make clinical decisions in realistic scenarios that closely mimic real-life interactions. The analysis finds that large-language models excel at making diagnoses from exam-style questions but struggle to do so from conversational notes. The researchers propose set of guidelines to optimize AI tools' performance and align them with real-world practice before integrating them into the clinic.
Categories: Science

How does a hula hoop master gravity? Mathematicians prove that shape matters

Computers and Math from Science Daily Feed - Thu, 01/02/2025 - 1:26pm
Hula hooping is so commonplace that we may overlook some interesting questions it raises: 'What keeps a hula hoop up against gravity?' and 'Are some body types better for hula hooping than others?' A team of mathematicians explored and answered these questions with findings that also point to new ways to better harness energy and improve robotic positioners.
Categories: Science

How does a hula hoop master gravity? Mathematicians prove that shape matters

Matter and energy from Science Daily Feed - Thu, 01/02/2025 - 1:26pm
Hula hooping is so commonplace that we may overlook some interesting questions it raises: 'What keeps a hula hoop up against gravity?' and 'Are some body types better for hula hooping than others?' A team of mathematicians explored and answered these questions with findings that also point to new ways to better harness energy and improve robotic positioners.
Categories: Science

Water treatment: catching steroid hormones with nanotubes

Matter and energy from Science Daily Feed - Thu, 01/02/2025 - 1:26pm
Steroid hormones are among the most widespread aquatic micropollutants. They are harmful to human health, and they cause ecological imbalances in aquatic environments. Researchers investigated how steroid hormones are degraded in an electrochemical membrane reactor with carbon nanotube membranes. They found that adsorption of steroid hormones on the carbon nanotubes did not limit the hormones' subsequent degradation.
Categories: Science

Artificial intelligence: Algorithms improve medical image analysis

Computers and Math from Science Daily Feed - Thu, 01/02/2025 - 1:26pm
Artificial intelligence has the potential to improve the analysis of medical image data. For example, algorithms based on deep learning can determine the location and size of tumors. This is the result of AutoPET, an international competition in medical image analysis. The seven best autoPET teams report on how algorithms can detect tumor lesions in positron emission tomography (PET) and computed tomography (CT).
Categories: Science

Big leap forward for environmentally friendly 'e-textiles' technology

Matter and energy from Science Daily Feed - Thu, 01/02/2025 - 1:25pm
A research team has shown wearable electronic textiles (e-textiles) can be both sustainable and biodegradable.
Categories: Science

Chemists create eco-friendly method to make chlorine-based materials for drugs and chemicals

Matter and energy from Science Daily Feed - Thu, 01/02/2025 - 1:25pm
Chlorine plays an essential part in daily life, from keeping pools clean to preserving food. Now, a team of chemists developed a more environmentally friendly way to integrate chlorine into chemical building blocks for medications, plastics, pesticides and other essential products while reducing costs.
Categories: Science

Building better infrared sensors

Matter and energy from Science Daily Feed - Thu, 01/02/2025 - 1:23pm
Researchers developed a type of infrared photodiode that is 35% more responsive at 1.55 m, the key wavelength for telecommunications, compared to other germanium-based components.
Categories: Science

Building better infrared sensors

Computers and Math from Science Daily Feed - Thu, 01/02/2025 - 1:23pm
Researchers developed a type of infrared photodiode that is 35% more responsive at 1.55 m, the key wavelength for telecommunications, compared to other germanium-based components.
Categories: Science

New method turns e-waste to gold

Matter and energy from Science Daily Feed - Thu, 01/02/2025 - 1:23pm
A research team has developed a method for extracting gold from electronics waste, then using the recovered precious metal as a catalyst for converting carbon dioxide (CO2), a greenhouse gas, to organic materials.
Categories: Science

Detecting disease with only a single molecule

Matter and energy from Science Daily Feed - Thu, 01/02/2025 - 1:22pm
Scientists have developed a nanopore-based tool that could help diagnose illnesses much faster and with greater precision than current tests allow, by capturing signals from individual molecules.
Categories: Science

Could Habitable White Dwarf Planets Retain Their Oceans? Maybe.

Universe Today Feed - Thu, 01/02/2025 - 12:22pm

Potentially habitable exoplanets are so incredibly common that astronomers have started to consider more unusual situations where life might arise. Perhaps life can be found on the moon of a hot Jupiter or lingering in the warm ocean of a rogue planet. Recently, there has even been the idea that habitable worlds might orbit white dwarfs. We know some white dwarfs have planets, and despite lacking nuclear fusion, white dwarfs do emit enough light and heat to have a habitable zone. But the question remains whether a planet could retain a water-rich environment through the red giant stage of a star before it becomes a white dwarf. This is the focus of a new study on the arXiv.

The study starts by stating the obvious. Any habitable world around a main-sequence star will likely be stripped of its atmosphere and water as the star swells to a red giant. By the time the star becomes a white dwarf, any planet that was habitable will be barren, if not consumed by its star. The work then goes on to consider more distant worlds in a system. Perhaps a cold and icy hycean world might become habitable in the white dwarf stage.

It turns out there are two critical stages. The first is that an ocean world would need to retain a large portion of its water during the dying stage of the main sequence star. As you might expect, the more distant a planet is from its star, the more water it retains. For a sunlike star, an ocean world would need to be more than three times Earth’s distance to retain water. To retain vast oceans similar to Earth, the planet would have to be about 10 AU away, or roughly the distance of Saturn.

Water retention for planets at different distances. Credit: Becker, et al

The second critical stage is orbital migration. Once the star becomes a white dwarf, an ocean world at Saturn’s orbit would be an ice planet far beyond the habitable zone. To become a living world, it would need to move inward to a close, warm orbit. This is possible both through interaction with the nebula formed during the red giant stage, as well as through gravitational interactions between planets. Our own solar system, for example, had a migration phase in its youth. As the study shows, however, the timing of this migration is critical. If the inward migration of a world happens too soon, then much of the water will boil off. If it happens too late, then the system will have stabilized to the point that the world won’t be able to enter the habitable zone.

Overall, the study finds that most worlds around a white dwarf will either be dry before entering the habitable zone, or retain water and remain at the outer edge of the system. But as the authors point out, it is *possible* for an outer hycean world to migrate at just the right time to retain water and become a warm Earth-like world. Not likely, but possible.

So finding a habitable planet around a white dwarf is a long shot. But given how easy it might be to study the atmospheres of these worlds, it’s certainly worth taking a look.

Reference: Becker, Juliette, Andrew Vanderburg, and Joseph Livesey. “The Fate of Oceans on First-Generation Planets Orbiting White Dwarfs.” arXiv preprint arXiv:2412.12056 (2024).

The post Could Habitable White Dwarf Planets Retain Their Oceans? Maybe. appeared first on Universe Today.

Categories: Science

Is There a Fundamental Logic to Life?

Universe Today Feed - Thu, 01/02/2025 - 12:12pm

One of the more daunting questions related to astrobiology—the search for life in the cosmos—concerns the nature of life itself. For over a century, biologists have known that life on Earth comes down to the basic building blocks of DNA, RNA, and amino acids. What’s more, studies of the fossil record have shown that life has been subject to many evolutionary pathways leading to diverse organisms. At the same time, there is ample evidence that convergence and constraints play a strong role in limiting the types of evolutionary domains life can achieve.

For astrobiologists, this naturally raises questions about extraterrestrial life, which is currently constrained by our limited frame of reference. For instance, can scientists predict what life may be like on other planets based on what is known about life here on Earth? An international team led by researchers from the Santa Fe Institute (SFI) addressed these and other questions in a recent paper. After considering case studies across various fields, they conclude that certain fundamental limits prevent some life forms from existing.

The research team was led by Ricard Solé, the head of the ICREA-Complex Systems Lab at the Universitat Pompeu Fabra and an External Professor at the Santa Fe Institute (SFI). He was joined by multiple SFI colleagues and researchers from the Institute of Biology at the University of Graz, the Complex Multilayer Networks Lab, the Padua Center for Network Medicine (PCNM), Umeå University, the Massachusetts Institute of Technology (MIT), the Georgia Institute of Technology, the Tokyo Institute of Technology, and the European Centre for Living Technology (ECLT).

Artist’s impression of Earth during the Archean Eon. Credit: Smithsonian National Museum of Natural History

The team considered what an interstellar probe might find if it landed on an exoplanet and began looking for signs of life. How might such a mission recognize life that evolved in a biosphere different from what exists here on Earth? Assuming physical and chemical pre-conditions are required for life to emerge, the odds would likely be much greater. However, the issue becomes far more complex when one looks beyond evolutionary biology and astrobiology to consider synthetic biology and bioengineering.

According to Solé and his team, all of these considerations (taken together) come down to one question: can scientists predict what possible living forms of organization exist beyond what we know from Earth’s biosphere? Between not knowing what to look for and the challenge of synthetic biology, said Solé, this presents a major challenge for astrobiologists:

“The big issue is the detection of biosignatures. Detecting exoplanet atmospheres with the proper resolution is becoming a reality and will improve over the following decades. But how do we define a solid criterion to say that a measured chemical composition is connected to life? 

“[Synthetic biology] will be a parallel thread in this adventure. Synthetic life can provide profound clues on what to expect and how likely it is under given conditions. To us, synthetic biology is a powerful way to interrogate nature about the possible.”

The sequence where amino acids and peptides come together to form organic cells. Credit: peptidesciences.com

To investigate these fundamental questions, the team considered case studies from thermodynamics, computation, genetics, cellular development, brain science, ecology, and evolution. They also consider previous research attempting to model evolution based on convergent evolution (different species independently evolve similar traits or behaviors), natural selection, and the limits imposed by a biosphere. From this, said Solé, they identified certain requirements that all lifeforms exhibit:

“We have looked at the most fundamental level: the logic of life across sales, given several informational, physical, and chemical boundaries that seem to be inescapable. Cells as fundamental units, for example, seem to be an expected attractor in terms of structure: vesicles and micelles are automatically formed and allow for the emergence of discrete units.”

The authors also point to historical examples where people predicted some complex features of life that biologists later confirmed. A major example is Erwin Schrödinger’s 1944 book What is Life? in which he predicted that genetic material is an aperiodic crystal—a non-repeating structure that still has a precise arrangement—that encodes information that guides the development of an organism. This proposal inspired James Watson and Francis Crick to conduct research that would lead them to discover the structure of DNA in 1953.

However, said Solé, there is also the work of John von Neumann that was years ahead of the molecular biology revolution. He and his team refer to von Neumann’s “universal constructor” concept, a model for a self-replicating machine based on the logic of cellular life and reproduction. “Life could, in principle, adopt very diverse configurations, but we claim that all life forms will share some inevitable features, such as linear information polymers or the presence of parasites,” Solé summarized.

The first implementation of von Neumann’s self-reproducing universal constructor. Three generations of machines are shown: the second has nearly finished constructing the third. Credit: Wikimedia/Ferkel

In the meantime, he added, much needs to be done before astrobiology can confidently predict what forms life could take in our Universe:

“We propose a set of case studies that cover a broad range of life complexity properties. This provides a well-defined road map to developing the fundamentals. In some cases, such as the inevitability of parasites, the observation is enormously strong, and we have some intuitions about why this happens, but not yet a theoretical argument that is universal. Developing and proving these ideas will require novel connections among diverse fields, from computation and synthetic biology to ecology and evolution.”

The team’s paper, “Fundamental constraints to the logic of living systems,” appeared in Interface Focus (a Royal Society publication).

Further Reading: Santa Fe Institute, Interface Focus

The post Is There a Fundamental Logic to Life? appeared first on Universe Today.

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