Latest news with #UniversityofMontpellier
The Star
17-07-2025
- Science
- The Star
Alpha males are rare among our fellow primates: scientists
During the research, it showed that for most primates, including lemurs, the females dominated the males. — Pixabay New research has contradicted the commonly held idea that males dominate females among primates, revealing far more nuanced power dynamics in the relationships of our close relatives. 'For a long time we have had a completely binary view of this issue. We thought that a species was either dominated by males or females – and that this was a fixed trait,' said Elise Huchard, a primatologist at the University of Montpellier in France. 'Recently, this idea has been challenged by studies showing that the truth is much more complicated,' said the lead author of a new study published in the journal PNAS. The French-German team of researchers combed through scientific literature for interactions between male and female primates that revealed their hierarchical relationships. These included aggression, threats and signs of dominant or submissive behaviour, such as when one primate spontaneously moved out of the way of another. Over five years, the team gathered data from 253 populations across 121 primate species, including a range of monkeys, lemurs, tarsiers and lorises. They found that confrontations between members of the opposite sex were much more frequent than had been previously thought. On average, more than half of these interactions within a group involved a male and a female. Males clearly dominating females – which was defined as winning more than 90% of these confrontations – was only observed in 17% of the populations. Among this minority were baboons and chimpanzees, which are the closest living relatives to humans. Clear female domination was recorded in 13% of the primate populations, including lemurs and bonobos. This meant that for 70% of the primates, either males or females could be at the top of the pecking order. Male baboons guard ovulating females so that other males can't get close. Battle of the sexes When male domination was particularly pronounced, it was usually in a species where males have a clear physical advantage, such as bigger bodies or teeth. It was also more common among ground-bound species, in which females are less able to run and hide compared to their relatives living in the trees. Females, meanwhile, tended to dominate over societies when they exerted control over reproduction. For example, the genitals of female baboons swell when they are ovulating. Males jealously guard females during these few days of their menstrual cycle, making sure that other competitors cannot mate with them. However in bonobos, this sexual swelling is less obvious. 'Males never know when they are ovulating or not. As a result, (the female bonobos) can mate with whoever they want, whenever they want, much more easily,' Huchard said. Female dominance is also more common when females compete with each other, and when males provide more care for the young. In these species, females are often solitary or only live in male-female pairs. This means that monogamy is closely linked to female dominance. Can these results be extrapolated to our own species? There are a great many differences between humans and our fellow primates, Huchard emphasised. But we would broadly fall into the middle category in which neither males nor females always have strict dominance over the other. 'These results corroborate quite well with what we know about male-female relationships among hunter-gatherers, which were more egalitarian than in the agricultural societies that emerged later' in human history, Huchard said. – AFP
The Guardian
14-07-2025
- Science
- The Guardian
Killer in the nest: how young storks are being strangled by plastic
On a late spring morning in the farmlands of southern Portugal, Dr Marta Acácio set her ladder against a tree and began to climb. Four metres up, she reached the giant white stork nest that was her goal. She knew from telescopic camera shots there was a healthy looking chick inside – and now she wanted to ring it. But when Acácio, an ecologist from University of Montpellier in France, tried to scoop up the chick, it would not come away: it was tethered to the nest by a piece of plastic baler twine. She turned the chick over and recoiled: its belly was a mass of maggots. 'It was being eaten alive from underneath,' says Acácio. With the pocketknife she now carries for dealing with this increasingly common situation, she cut the twine away, put the chick in a carrier bag and climbed back down. She and her colleagues cleaned and disinfected the wound before returning the chick to the nest. 'I was hopeful that the chick would survive,' she says. 'But unfortunately it did not recover from the wounds.' The nest was one of 93 a team of ecologists inspected weekly during the 2023 breeding season. Storks build gigantic nests over decades, weighing up to 1,000kg (2,200lb). They balance not just on branches, but on structures such as telephone poles. Many other bird species, including sparrows, starlings and kestrels, live within the nests. 'The stork nest is actually a colony of other species. It's a fantastic species,' says prof Aldina Franco, an ecologist at the University of East Anglia (UEA) and member of the research team. The scientists were following a hunch that they – and ecologists around the world – were missing a hidden death toll from plastic that birds incorporated into their nests. Scientists tend to inspect nests only at fledging time, yet dead chicks can be swiftly discarded by parents, so those killed by plastic early in their lives might go uncounted. Over four years, the researchers from UEA and Lisbon University photographed nearly 600 white stork (Ciconia ciconia) nests. Then, in each week of the 2023 breeding season, Acácio and Ursula Heinze of UEA physically inspected a selection of nests. The results, published in the journal Ecological Indicators on Monday, are alarming. About 90% of the 600 photographed nests contained plastic. In those the scientists climbed up to, more than a quarter – 27% – contained entangled chicks. Most were only two weeks old. The chief culprit was baler twine, a plastic string used to secure hay bales: either the twine or its wrapping was responsible for almost all the entangled chicks. A few were caught up in domestic plastics such as bags or milk containers. The chicks died from strangulation, amputation and infected wounds. 'They roll and roll and they go around and it's almost as if they tie the rope around their legs even harder as they move,' Franco says. Acácio likes to talk about successful rescues, too. Once, she peered into a nest built on the stump of a cork oak tree to find two three-week-old siblings, their limbs coiled in spirals of blue baler twine. 'I thought the chicks were so badly entangled that neither would survive,' says Acácio, 'Unfortunately the smaller chick did not survive but the larger one, which still has the marks of the entanglement, survived and fledged.' Birds on every continent use plastic and other human litter in their nests. The downsides of plastic debris are well known in the marine world, with graphic images of plastic harming turtles, seabirds and fish. But less is known about its effect on land-based birds. 'This is not a Portuguese problem or even a white stork problem,' says Dr Inês Catry, an avian ecologist at the University of Lisbon who led the project. 'Baler twine is widespread in many areas in many countries.' The few other studies that have been done, in the Americas and Europe, have not involved weekly nest visits and have found lower entanglement rates, of 0.3% to 5.6%. This study found a nestling entanglement rate of 12%. Sign up to Global Dispatch Get a different world view with a roundup of the best news, features and pictures, curated by our global development team after newsletter promotion In Montana in the US, Marco Restani, a wildlife biologist for the power company NorthWestern Energy, has been working with volunteers to monitor ospreys that nest along 600km of the Yellowstone River. Restani says that while plastic entanglement is not yet a population-level threat to ospreys, the cases he does find are 'gruesome'. 'It's a horrible way to die. And it's horrible for people who are discovering it as well.' In Argentina, Dr María Soledad Liébana, a raptor biologist at the Institute of Earth and Environmental Sciences of La Pampa, has studied plastic entanglement among baby southern caracaras, a type of raptor. 'Plastic entanglement does appear to be a serious and growing threat to a wide range of bird species, across many different regions of the world,' she says. For birds already under threat from other factors, a 12% entanglement rate could 'apply a lot of pressure', says Dr Neil James, an ecologist at Scotland's University of the Highlands and Islands. James founded a website in 2019, to which anyone can report entanglements and human debris found in nests. So far, the nests of an 'alarming' 160 species globally have been reported to contain human debris and two-thirds of these are terrestrial, he says. Baler twine is accumulating in the landscape at a formidable rate, say Heinze's team. The market was worth $300m (£220m) globally in 2023 and 80,000 tonnes were being used annually across Europe as of 2019. How much of this leaks into the environment is unknown. While farmers play a crucial role in preventing plastic leaking into the environment – for example by ensuring no plastic debris is left in the field – many aspects of the plastic footprint are out of their control, such as whether there are recycling facilities nearby or whether there are any biodegradable alternatives. Collection schemes are patchy across Europe but research has found that where they are offered they have been successful. Scientists are researching how to replace polypropylene twine, and some biodegradable twines are already on the market. In the meantime, for some of the white storks, there is one simple step that could help, says Heinze: mow under their nests. This provides the birds with a convenient abundance of natural nesting material and reduces the amount of plastic they use. Find more age of extinction coverage here, and follow the biodiversity reporters Phoebe Weston and Patrick Greenfield in the Guardian app for more nature coverage
LeMonde
13-07-2025
- Science
- LeMonde
AI's turbulent history, from the calculator to ChatGPT
On an internet forum, a slightly confused student asked a not-so-silly question: "Did the definition of AI [artificial intelligence] change?" Another replied, sounding disillusioned: "I just don't really regard this as an academic term [that I'd use] anymore (…) it may not be clear to a person reading it." The use of the term "artificial intelligence" has indeed never been fully consistent. Experts generally agree on a preliminary definition: AI is a machine capable of carrying out tasks previously thought to require human intelligence. "But what is human intelligence?" asked Anne Laurent, a computer science researcher and director of the Inria branch at the University of Montpellier. "Philosophers, engineers and cognitive scientists do not agree. Its definition changes over time." If we look at the broad history of AI, it may have been in the 19 th century that the first human intelligence skill fell, conquered by calculating machines capable of multiplying and dividing. But a narrower view often prevails, placing the birth of AI in the 1940s with the emergence of the computer. 1940s: The foundation One of the very first electronic computers, the Colossus, was used by the British military to break the encrypted communications of the German high command. It was far more powerful than the electromechanical machines that came before it. The machines that followed would be easier to program and capable of running complex and varied algorithms, finally making it possible to experiment with theories about "thinking" machines, which began to circulate at the time. As early as 1943, Walter Pitts and Warren McCulloch imagined the concept of artificial neurons, a simplified model of how human neurons function.
Miami Herald
11-07-2025
- Science
- Miami Herald
Invasive carnivore plaguing Florida can completely absorb skeletons, study says
The invasive Burmese pythons plaguing Florida have an almost supernatural ability to absorb skeletons and scientists say they have finally found out how it's done. Turns out the intimidating predators have 'previously unknown cell type' in the walls of their intestines that completely dissolves skeletons, according to a study published June 25 in the Journal of Experimental Biology. The revelation helps explain why the giant snakes — which can grow to 18 feet in Florida — are not afraid to swallow creatures that are nearly equal in size, experts say. Professor Jehan-Hervé Lignot of the University of Montpellier in France is credited with making the discovery, using captive juvenile pythons as his test subjects. It has long been known that bones went into pythons and never came out the other end, but the 'mechanisms that enable them to do this have remained mysterious until now,' Lignot told Eureka Alert! To solve the mystery, researchers fed three types of meals to young pythons: Whole rodents, rodents with no bones, and boneless rodents injected with calcium carbonate, the study reports. It became clear that the intestines of the snakes reacted differently when they were fed whole rodents or rodents injected with calcium, the researchers said. Not only were they able to completely dissolve the skeletons, but they also were able to excrete excess calcium in cases where too much bone was consumed, tests showed. Not even fragments of bones showed up in their feces, the team found. 'This study revealed the presence of a new type of cell along the intestine that is involved in the production of large particles made from calcium, phosphorus and iron,' a July 9 news release says. 'When fed with boneless prey, these calcium and phosphorus-rich particles were not produced.' The newly discovered 'bone-digesting cell' has since been found in other species of pythons and boas, along with venomous Gila monsters native to the Southwestern United States and Mexico, the study reports. 'Marine predators that eat bony fish or aquatic mammals must face the same problem,' Lignot said in the release. 'Birds that eat mostly bones, such as the bearded vulture, would be fascinating candidates too.' Native to Southeast Asia, burmese pythons were introduced to South Florida 'due to accidental or intentional release of captive pet animals,' the Florida Fish and Wildlife Conservation Commission reports. The snakes have no natural enemies in Florida and they are creating havoc with the ecosystem by preying on native wildlife, including deer and alligators, experts say. In 2022, the Conservancy of Southwest Florida discovered a 115-pound python in the process of swallowing a 77-pound deer, which amounted to 66.9% of the snake's body mass, officials said. A study published in 2024 also revealed the predators are capable of eating each other, McClatchy News reported.
Time of India
10-07-2025
- Health
- Time of India
Burmese pythons have bone-digesting cells that allow them to convert entire prey into nutrition; scientists reveal
Source: Joel Sartore In a remarkable discovery that deepens our understanding of how predators digest whole prey, scientists have found that Burmese pythons (Python bivittatus) possess specialised intestinal cells that help process calcium from the bones of their meals. This research not only explains how these large snakes handle mineral-rich diets but also hints at a broader evolutionary adaptation among whole-prey eaters. The study, published on June 25 in the Journal of Experimental Biology , uncovers the mechanism behind how pythons manage the calcium overload that results from consuming entire animals—bones and all. How burmese pythons digest whole prey: Study explains Burmese pythons, native to Southeast Asia and invasive in parts of Florida, are ambush predators that feed on birds and small mammals. Uniquely, they swallow their prey whole and then retreat for days while their powerful digestive systems do the work. Though they may go weeks without eating, when they do feast, they must digest everything—including bones, which provide essential nutrients like calcium and phosphorus. However, this introduces a challenge: too much calcium can be toxic. To investigate this, researchers from the University of Montpellier in France, including co-author Jehan-Hervé Lignot, fed Burmese pythons three different diets: Whole prey (with bones) Boneless prey (low calcium) Boneless prey + calcium supplements They then studied the snakes' intestinal tissue to examine how each diet impacted calcium processing. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like An engineer reveals: One simple trick to get internet without a subscription Techno Mag Learn More Undo Source: Live Science Bone-digesting intestinal cells discovery The team discovered narrow, specialised cells in the snakes' intestinal lining that appear to manage the digestion of bones. In snakes fed either whole prey or boneless prey with calcium supplements, these cells contained tiny particles made of calcium, phosphorus, and iron. However, these mineral particles were absent in snakes that were fed boneless prey only—confirming the link between these particles and calcium intake. The researchers believe these cells help remove excess calcium by forming solid particles, which are later expelled through the feces. This adaptation allows the snake to benefit from the nutrients in bones without suffering from calcium toxicity. Are these cells found in other animals Interestingly, after finding these cells in Burmese pythons, scientists also observed similar cells in other whole-prey reptiles, including: Other species of pythons Boas Gila monsters (Heloderma suspectum) These reptiles share one thing in common: they swallow prey whole. However, scientists have not yet found similar calcium-processing cells in animals like dolphins or fish-eating birds, despite their similar feeding habits. What bone-eating predators might reveal next This discovery opens the door for further research into how different predators manage mineral overloads from consuming bones. As study co-author Lignot pointed out, animals such as marine mammals and bone-eating birds (e.g., the bearded vulture, Gypaetus barbatus) could possess similar adaptations—or entirely different mechanisms. Understanding these differences could help scientists learn how digestion, mineral processing, and evolutionary pressures shape feeding strategies across species. Also Read | Chihuahua becomes 'Glacier Hero' after saving owner from 26-foot fall into icy crevasse in Switzerland
