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Marmots could have the solution to a long-running debate in evolution

New Scientist Feed - Thu, 11/07/2024 - 10:00am
When it comes to the survival of animals living in the wild, the characteristics of the group can matter as much as the traits of the individual, according to a study in marmots
Categories: Science

Plastic device aids robot-assisted heart surgery

Matter and energy from Science Daily Feed - Thu, 11/07/2024 - 8:54am
A team has developed a plastic surgical field expansion plate that can help surgeons during robot-assisted heart surgery.
Categories: Science

Plastic device aids robot-assisted heart surgery

Computers and Math from Science Daily Feed - Thu, 11/07/2024 - 8:54am
A team has developed a plastic surgical field expansion plate that can help surgeons during robot-assisted heart surgery.
Categories: Science

GPS system for microorganisms could revolutionize police work

Matter and energy from Science Daily Feed - Thu, 11/07/2024 - 8:52am
A research team developed an AI tool that traces back the most recent places you have been to. The tool acts like a satellite navigation system, but instead of guiding you to your hotel, it identifies the geographical source of microorganisms. This means you can use bacteria to determine whether someone has just been to the beach, got off the train in the city center or taken a walk in the woods. This opens up new possibilities within medicine, epidemiology and forensics.
Categories: Science

Off-the-shelf thermoelectric generators can upgrade CO2 into chemicals: The combination could help us colonize Mars

Matter and energy from Science Daily Feed - Thu, 11/07/2024 - 8:52am
Readily available thermoelectric generators operating under modest temperature differences can power CO2 conversion, according to a proof-of-concept study by chemists. The findings open up the intriguing possibility that the temperature differentials encountered in an array of environments -- from a typical geothermal installation on Earth to the cold, desolate surface of Mars -- could power the conversion of CO2 into a range of useful fuels and chemicals.
Categories: Science

Off-the-shelf thermoelectric generators can upgrade CO2 into chemicals: The combination could help us colonize Mars

Space and time from Science Daily Feed - Thu, 11/07/2024 - 8:52am
Readily available thermoelectric generators operating under modest temperature differences can power CO2 conversion, according to a proof-of-concept study by chemists. The findings open up the intriguing possibility that the temperature differentials encountered in an array of environments -- from a typical geothermal installation on Earth to the cold, desolate surface of Mars -- could power the conversion of CO2 into a range of useful fuels and chemicals.
Categories: Science

Microplastics impact cloud formation, likely affecting weather and climate

Matter and energy from Science Daily Feed - Thu, 11/07/2024 - 8:52am
Scientists have spotted microplastics, tiny pieces of plastic smaller than 5 millimeters, in some of the most pristine environments on Earth, from the depths of the Mariana Trench to the snow on Mt. Everest to the mountaintop clouds of China and Japan. Microplastics have been detected in human brains, the bellies of sea turtles and the roots of plants. Now, research reveals that microplastics in the atmosphere could be affecting weather and climate.
Categories: Science

The real reason VAR infuriates football fans and how to fix it

New Scientist Feed - Thu, 11/07/2024 - 8:10am
The controversies surrounding football’s video assistant referee (VAR) system highlight our troubled relationship with uncertainty – and point to potential solutions
Categories: Science

Carbon emissions from private jets have exploded in recent years

New Scientist Feed - Thu, 11/07/2024 - 8:00am
The climate impact of flights taken by the super-rich rose sharply from 2019 to 2023, fuelling calls for a carbon tax on private aviation
Categories: Science

Chinese rover finds further evidence for an ancient ocean on Mars

New Scientist Feed - Thu, 11/07/2024 - 8:00am
Data collected by the Zhurong rover and orbiting satellites suggests the existence of an ancient shoreline in the Utopia Planitia region of Mars
Categories: Science

DNA analysis rewrites the stories of people buried in Pompeii

New Scientist Feed - Thu, 11/07/2024 - 8:00am
Genetic analysis of five individuals preserved as plaster casts in the ruins of Pompeii contradicts established beliefs about the people and their relationships
Categories: Science

Readers’ wildlife photos

Why Evolution is True Feed - Thu, 11/07/2024 - 6:15am

If you have good wildlife photos, please send them in, as we always need more.  Today we have a word-and-picture post on butterflies contributed by Athayde Tonhasca Júnior. His words are indented, and you can enlarge the photos by clicking on them:

Fluttering souls

We may be unsympathetic to celebrities who moan about the encumbrances of being gorgeous, but not the Greek princess Psyche. Her striking beauty sent the goddess of love Aphrodite (Venus to the Romans) into a not so loving fit of jealousy. She devised a cunning plan; to dispatch her son Eros (Cupid) on a mission to make Psyche fall in love with the ugliest, wickedest man he could find. But Aphrodite should have taken a hint from her son’s name: Eros spoiled mum’s revenge by falling in love with Psyche. That didn’t work too well for the princess; she became separated from Eros and fell into the clutches of a resentful Aphrodite, who imposed upon her a series of terrible tasks. After many twists and turns worthy of a Mexican telenovela – you can read it all in Metamorphoses – the lovers were reunited. Zeus, Heaven’s Big Cheese, took pity on Psyche. He made her immortal and gave her in marriage to Eros. A happy ending.

Psyche’s tribulations and eventual redemption spoke of mortals’ aspirations, so in her newly acquired divine status, the princess became the goddess of the human soul. For the ancient Greeks, a dying person would breathe out his or her soul, which would fly to the underworld in the form of flickering shadows or spirits. In his History of Animals, Aristotle (384–322 BC) wrote that a butterfly’s cocoon was like a tomb, and the adult insect emerging from it was like the soul fluttering away from a human body after death. It’s no surprise then that the Greek word ψυχή (Psykhe) was used for ‘soul’ and ‘butterfly’. The representation of the soul as a butterfly was an appropriate symbol of the fragility and shortness of life, and that connection explains why goddess Psyche was often represented as a butterfly or as a maiden with butterfly wings.

Psyche, by Pietro Tenerani (1789-1869) © Paolobon140, Wikimedia Commons:

Butterflies have much more to do with humans than merely representing the wanderings of our soul. Their colours and wing patterns, their gentleness and fragility and amazing life cycles have long enthralled naturalists, artists and writers. More books have been written about butterflies than any other insect. Butterflies don’t share the PR problem facing wasps, spiders and other invertebrates that are commonly lumped together as creepy crawlies. Most people like butterflies. Sometimes the attraction is excessive: over-collecting by amateurs, naturalists, and biologists menaces many butterfly species.

The butterfly hunter, by Carl Spitzweg (1808–1885) © Museum Wiesbaden, Wikimedia Commons:

Butterflies are among our commonest and certainly most flamboyant garden visitors. We see them gracefully hopping from flower to flower, probing them with their conspicuous proboscis (tubular, flexible and elongated mouthparts specialised for sucking) for a sip of nectar. So, reasonably, we may assume these plant-insect associations are evidence for psychophily (pollination by butterflies). But that would be a too-hasty conclusion.

Psykhe brought us words such as psychology, psychedelic, psychopath, psycho, psychosomatic, psychomotor and psychophily – the latter illustrated by this pollen-carrying skipper butterfly © Raju Kasambe, Wikimedia Commons:

 

It has long been known that flower visitation does not necessarily result in pollination. That will happen only when pollen grains from the stamen (the male part of the plant) are transferred to the stigma (the female part). But many factors interfere with this process: the visitor may only collect nectar, bypassing the all-important pollen. If pollen is collected, it may be dropped before reaching a receptive stigma, eaten, or taken away to feed the visitors’ brood. Pollen grains passively attached to the visitors’ body may be too few, or located on the wrong part of the body so that it does not contact a stigma. For a variety of reasons, most flower visitations have no bearing of plant fertilisation.

Butterflies are largely nectar drinkers, tapping flowers’ abundant reserves of sugars and amino acids. Some species get their nutrition from ripe or rotten fruit, tree sap, wet soil, animal carcasses and even tears. But with the exception of pollen-munching Heliconius spp. (Young & Montgomery, 2020), butterflies stick to a liquid diet. They rely on their proboscis, an intricate feeding apparatus that works as a drinking straw ranging in length from around 6 mm to a record 52.7 mm for the immaculate ruby-eye skipper (Damas immaculata) (Bauder et al., 2014).

The coiled proboscis of a butterfly © Atudu, Wikimedia Commons:

Pollen is inconsequential to most butterflies. They don’t collect it willingly and their bodies are not adapted to unintentionally transport significant amounts of pollen grains like bees and flies. And that is a problem for plants: they invest a lot of energy producing nectar to attract pollinators. If a visitor goes away with a bellyful of nectar but no pollen, the plant has been a victim of nectar theft (when visitors take nectar without pollinating the flower). Butterflies as a group may have evolved to be nectar thieves, which from the plants’ point of view is nothing short of parasitism (Wiklund et al., 1979). This form of larceny is not restricted to butterflies: bees, flies, birds and most other visitors will steal nectar if given the opportunity (Irwin et al., 2010). But most of the 20,400 or so described species of butterflies don’t compensate their thievery by pollinating their victims.

Butterfly visitors are detrimental or indifferent for a wide range of flowering plants. But, as invariably is the case in biology, things are not simple or straightforward. Butterflies are abundant flower visitors and some species are long distance flyers, therefore with great potential for pollen dispersal. Some plants have not let these traits go to waste: they adopted psychophily as their main or sometimes only means of sexual reproduction. A few plants do that by producing reproductive structures that facilitate pollen transfer by butterfly wings. Others, like the Carthusian pink (Dianthus carthusianorum), hide their nectar at the bottom of narrow, tubular flowers that exclude most visitors, but not butterflies with long proboscises. While moths can take nectar while hovering over a flower, butterflies need to land to feed. The Carthusian pink obliges them with flowers shaped with a flat rim, which is a convenient landing platform for butterflies. This European plant is found in dry, grassy habitats of altitudes of up to 2,500 m, and it depends entirely on butterflies for pollination (Bloch et al., 2006).

Carthusian pink:

In some cases, butterflies intending to commit thievery have the table turned around on them, so that the would-be cheaters become the cheated.

Crucifix orchids (Epidendrum spp.) comprise over 1,400 species distributed from the southeastern United States to northern Argentina. This group of plants is highly diverse morphologically and ecologically, but most investigated species share one feature: a dry cuniculus. This structure is concealed in the column (the fused reproductive parts characteristic of orchids) and normally functions as a nectar reservoir. The majority of crucifix orchids have no nectar to bargain, but that doesn’t deter a range of butterflies. Probably attracted by the orchid’s scents, they probe the flower’s column and cuniculus in search of a non-existent reward. Ending up empty-handed is not the butterflies’ sole unpleasant surprise: the floral tube is narrow and bent, so that a visitor has to struggle to retract its proboscis. This temporary detainment – which could last for over one hour – increases the chances of a butterfly leaving the flower with pollinia (a blob of pollen) attached to its proboscis. This stratagem works very well for the orchids, so that butterflies and some day-flying moths are their only or main pollinators.

(A) Epidendrum densiflorum inflorescence; (B) Dissected flower and detail of column; (C) Flower in longitudinal section, showing the empty cuniculus © Silveira et al., 2023.

Butterflies do not belong to pollinators’ Premier League, but the Carthusian pink, crucifix orchids and several other plants demonstrate that psychophily is not that rare. Butterflies fly over large distances, are attracted to a variety of plants and make repeated visits to flowers. These features must compensate for some of their shortcomings, and we surely have much more to discover about their role in plant reproduction.

Themisto amberwing (Methona themisto), an orchid pollinator © Evaldo Resende, Wikimedia Commons:

Categories: Science

#Oatzempic – The viral oat-based alternative to Ozempic?

Science-based Medicine Feed - Thu, 11/07/2024 - 5:00am

Can the Oatzempic diet deliver Ozempic-like weight loss?

The post #Oatzempic – The viral oat-based alternative to Ozempic? first appeared on Science-Based Medicine.
Categories: Science

Power grids supplied largely by renewable sources experience lower intensity blackouts

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 2:18pm
New research into the vulnerability of power grids served by weather-dependent renewable energy sources (WD-RESs) such as solar and wind paints a hopeful picture as various countries around the globe attempt to meet their climate emissions targets -- with the research showing grids with high penetration of WD-RESs tend to have reduced blackout intensities in the US.
Categories: Science

Scientists calculate predictions for meson measurements

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 2:18pm
Calculations of charge distribution in mesons provide benchmark for experimental measurements and validate widely used 'factorization' method for imaging the building blocks of matter.
Categories: Science

Ancient Egyptians shaped sheep's horns – and we don't know why

New Scientist Feed - Wed, 11/06/2024 - 2:05pm
The earliest evidence of livestock with modified horns has been discovered in ancient Egypt – sheep skulls with horns that point in unnatural directions suggest humans forced them to grow that way
Categories: Science

Knots made in a weird quantum fluid can last forever

New Scientist Feed - Wed, 11/06/2024 - 12:15pm
Shapes created by vortices in water often fall apart, but an odd quantum fluid made from ultracold atoms could support vortex knots that never lose their knottiness
Categories: Science

A new approach to modeling complex biological systems

Computers and Math from Science Daily Feed - Wed, 11/06/2024 - 11:27am
Biological engineers developed a computational approach to extracting useful information from large biological datasets. They showed they could unravel interactions that determine how the immune system responds to tuberculosis vaccination and infection.
Categories: Science

Pathogens which cling to microplastics may survive wastewater treatment

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 11:26am
Wastewater treatment fails to kill several human pathogens when they hide out on microplastics in the water, according to a new study.
Categories: Science

'Shallow' sports and 'deep' social hierarchies: Not all pecking orders are created equal

Computers and Math from Science Daily Feed - Wed, 11/06/2024 - 11:26am
Researchers have added a new dimension to the mathematics used to predict the outcomes of all manner of competitions, including sports, games and social hierarchies in both humans and animals.
Categories: Science

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