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Neanderthals had the capacity to perceive and produce human speech

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Neanderthals had the capacity to perceive and produce human speech

Neanderthals — the closest ancestor to modern humans — possessed the ability to perceive and produce human speech, according to a new study published by an international multidisciplinary team of researchers including Binghamton University Associate Professor of Anthropology Rolf Quam and graduate student Alex Velez.

“This is one of the most important studies I have been involved in during my career,” said Quam. “The results are solid and clearly show the Neanderthals had the capacity to perceive and produce human speech. This is one of the very few current, ongoing research lines relying on fossil evidence to study the evolution of language, a notoriously tricky subject in anthropology.””

The evolution of language, and the linguistic capacities in Neanderthals in particular, is a long-standing question in human evolution.

“”For decades, one of the central questions in human evolutionary studies has been whether the human form of communication, spoken language, was also present in any other species of human ancestor, especially the Neanderthals,” said coauthor Juan Luis Arsuaga, professor of paleontology at the Universidad Complutense de Madrid and co-director of excavations and research at the Atapuerca archaeological sites in northern Spain. The latest study has reconstructed how Neanderthals heard to draw some inferences about how they may have communicated.

The study relied on high resolution CT scans to create virtual 3D models of the ear structures in Homo sapiens and Neanderthals as well as earlier fossils from the site of Atapuerca that represent ancestors of the Neanderthals. Data collected on the 3D models were entered into a software-based model, developed in the field of auditory bioengineering, to estimate the hearing abilities up to 5 kHz, which encompasses most of the frequency range of modern human speech sounds. Compared with the Atapuerca fossils, the Neanderthals showed slightly better hearing between 4-5 kHz, resembling modern humans more closely.

In addition, the researchers were able to calculate the frequency range of maximum sensitivity, technically known as the occupied bandwidth, in each species. The occupied bandwidth is related to the communication system, such that a wider bandwidth allows for a larger number of easily distinguishable acoustic signals to be used in the oral communication of a species. This, in turn, improves the efficiency of communication, the ability to deliver a clear message in the shortest amount of time. The Neanderthals show a wider bandwidth compared with their ancestors from Atapuerca, more closely resembling modern humans in this feature.

“This really is the key,” said Mercedes Conde-Valverde, professor at the Universidad de Alcalá in Spain and lead author of the study. “The presence of similar hearing abilities, particularly the bandwidth, demonstrates that the Neanderthals possessed a communication system that was as complex and efficient as modern human speech.”

“One of the other interesting results from the study was the suggestion that Neanderthal speech likely included an increased use of consonants,” said Quam. “Most previous studies of Neanderthal speech capacities focused on their ability to produce the main vowels in English spoken language. However, we feel this emphasis is misplaced, since the use of consonants is a way to include more information in the vocal signal and it also separates human speech and language from the communication patterns in nearly all other primates. The fact that our study picked up on this is a really interesting aspect of the research and is a novel suggestion regarding the linguistic capacities in our fossil ancestors.”

Thus, Neanderthals had a similar capacity to us to produce the sounds of human speech, and their ear was “tuned” to perceive these frequencies. This change in the auditory capacities in Neanderthals, compared with their ancestors from Atapuerca, parallels archaeological evidence for increasingly complex behavioral patterns, including changes in stone tool technology, domestication of fire and possible symbolic practices. Along these lines, the study provides strong evidence in favor of the coevolution of increasingly complex behaviors and increasing efficiency in vocal communication throughout the course of human evolution.

The team behind the new study has been developing this research line for nearly two decades, and has ongoing collaborations to extend the analyses to additional fossil species. For the moment, however, the new results are exciting.

“These results are particularly gratifying,” said Ignacio Martinez, a professor at Universidad de Alcalá in Spain. “We believe, after more than a century of research into this question, that we have provided a conclusive answer to the question of Neanderthal speech capacities.”

The study, “Neandertals and modern humans had similar auditory and speech capacities,” was published in Nature Ecology and Evolution.

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Large wildfires create weather that favors more fire

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Neanderthals had the capacity to perceive and produce human speech


A new UC Riverside study shows soot from large wildfires in California traps sunlight, making days warmer and drier than they ought to be.

Many studies look at the effect of climate change on wildfires. However, this study sought to understand the reverse — whether large fires are also changing the climate.

“I wanted to learn how the weather is affected by aerosols emitted by wildfires as they’re burning,” said lead study author and UCR doctoral candidate James Gomez.

To find his answers, Gomez analyzed peak fire days and emissions from every fire season over the past 20 years. Of these fire days, he examined a subset that occurred when temperatures were lower, and humidity was higher. “I looked at abnormally cool or wet days during fire season, both with and without fires. This mostly takes out the fire weather effects,” Gomez said.

Published in the journal Atmospheric Chemistry and Physics, the study found that large fires did have an effect. They made it hotter and drier than usual on the days the fires burned. The extra heat and aridity may then make conditions favorable for more fire.

“It appears these fires are creating their own fire weather,” Gomez said.

The most intense fires occurred in Northern California, where fire-fueling vegetation is denser than elsewhere in the state. On average, temperatures were about 1 degree Celsius warmer per day during the fires.

There are likely two reasons for this. One — soot traps heat, and two — the extra heat reduces humidity in the atmosphere, making it more difficult for clouds to form.

“Fires emit smoke with black carbon, or soot. Since it is very dark, the soot absorbs sunlight more readily than bright or reflective things,” Gomez said.

There are two types of aerosols: reflective and absorptive. Sulfate aerosols, which are byproducts of fossil fuel burning, are reflective and can cool the environment. These particles reflect the sun’s energy back into space, keeping it out of the atmosphere.

Recent UCR research points to an unfortunate byproduct of improving air quality by reducing sulfate aerosols. Since these particles have a cooling effect, removing them makes climate change more severe and leads to an increase in wildfires, especially in northern hemisphere forests.

Sulfate aerosols can also help make clouds brighter, more reflective, and more effective at cooling the planet.

The researchers note that the only way to prevent additional wildfires when cleaning up reflective sulfate air pollution is to simultaneously reduce emissions of greenhouse gases like carbon dioxide and methane.

Absorptive aerosols have the opposite effect. They trap light and heat in the atmosphere, which can raise temperatures. Black carbon, the most common aerosol emission from wildfires, is an absorbing aerosol. They not only directly make temperatures hotter, but indirectly as well by discouraging cloud formation and precipitation.

“What I found is that the black carbon emitted from these California wildfires is not increasing the number of clouds,” Gomez said. “It’s hydrophobic.” Fewer clouds mean less precipitation, which is problematic for drought-prone states.

While some studies have shown an association between fires and brighter, more numerous clouds, this one did not.

Notably, the study found that days with fewer fire emissions had a more muted effect on the weather. “If the aerosols are coming out in smaller amounts and more slowly, the heating effect is not as pronounced,” Gomez said.

Gomez is hopeful that mitigating CO2 emissions, alongside better land management practices, can help reduce the number of large wildfires.

“There is a buildup of vegetation here in California. We need to allow more frequent small fires to reduce the amount of fuel available to burn,” Gomez said. “With more forest management and more prescribed burns, we could have fewer giant fires. That is in our control.”



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Astronomers see a massive black hole awaken in real time

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Neanderthals had the capacity to perceive and produce human speech


In late 2019 the previously unremarkable galaxy SDSS1335+0728 suddenly started shining brighter than ever before. To understand why, astronomers have used data from several space and ground-based observatories, including the European Southern Observatory’s Very Large Telescope (ESO’s VLT), to track how the galaxy’s brightness has varied. In a study out today, they conclude that they are witnessing changes never seen before in a galaxy — likely the result of the sudden awakening of the massive black hole at its core.

Imagine you’ve been observing a distant galaxy for years, and it always seemed calm and inactive,” says Paula Sánchez Sáez, an astronomer at ESO in Germany and lead author of the study accepted for publication in Astronomy & Astrophysics. “Suddenly, its [core] starts showing dramatic changes in brightness, unlike any typical events we’ve seen before.” This is what happened to SDSS1335+0728, which is now classified as having an ‘active galactic nucleus’ (AGN) — a bright compact region powered by a massive black hole — after it brightened dramatically in December 2019 [1].

Some phenomena, like supernova explosions or tidal disruption events — when a star gets too close to a black hole and is torn apart — can make galaxies suddenly light up. But these brightness variations typically last only a few dozen or, at most, a few hundreds of days. SDSS1335+0728 is still growing brighter today, more than four years after it was first seen to ‘switch on’. Moreover, the variations detected in the galaxy, which is located 300 million light-years away in the constellation Virgo, are unlike any seen before, pointing astronomers towards a different explanation.

The team tried to understand these brightness variations using a combination of archival data and new observations from several facilities, including the X-shooter instrument on ESO’s VLT in Chile’s Atacama Desert [2]. Comparing the data taken before and after December 2019, they found that SDSS1335+0728 is now radiating much more light at ultraviolet, optical, and infrared wavelengths. The galaxy also started emitting X-rays in February 2024. “This behaviour is unprecedented,” says Sánchez Sáez, who is also affiliated with the Millennium Institute of Astrophysics (MAS) in Chile.

“The most tangible option to explain this phenomenon is that we are seeing how the [core] of the galaxy is beginning to show (…) activity,” says co-author Lorena Hernández García, from MAS and the University of Valparaíso in Chile. “If so, this would be the first time that we see the activation of a massive black hole in real time.”

Massive black holes — with masses over one hundred thousand times that of our Sun — exist at the centre of most galaxies, including the Milky Way. “These giant monsters usually are sleeping and not directly visible,” explains co-author Claudio Ricci, from the Diego Portales University, also in Chile. “In the case of SDSS1335+0728, we were able to observe the awakening of the massive black hole, [which] suddenly started to feast on gas available in its surroundings, becoming very bright.”

“[This] process (…) has never been observed before,” Hernández García says. Previous studies reported inactive galaxies becoming active after several years, but this is the first time the process itself — the awakening of the black hole — has been observed in real time. Ricci, who is also affiliated with the Kavli Institute for Astronomy and Astrophysics at Peking University, China, adds: “This is something that could happen also to our own Sgr A*, the massive black hole (…) located at the centre of our galaxy,” but it is unclear how likely this is to happen.

Follow-up observations are still needed to rule out alternative explanations. Another possibility is that we are seeing an unusually slow tidal disruption event, or even a new phenomenon. If it is in fact a tidal disruption event, this would be the longest and faintest such event ever observed. “Regardless of the nature of the variations, [this galaxy] provides valuable information on how black holes grow and evolve,” Sánchez Sáez says. “We expect that instruments like [MUSE on the VLT or those on the upcoming Extremely Large Telescope (ELT)] will be key in understanding [why the galaxy is brightening].”

Notes

[1] The SDSS1335+0728 galaxy’s unusual brightness variations were detected by the Zwicky Transient Facility (ZTF) telescope in the US. Following that, the Chilean-led Automatic Learning for the Rapid Classification of Events (ALeRCE) broker classified SDSS1335+0728 as an active galactic nucleus.

[2] The team collected archival data from NASA’s Wide-field Infrared Survey Explorer (WISE) and Galaxy Evolution Explorer (GALEX), the Two Micron All Sky Survey (2MASS), the Sloan Digital Sky Survey (SDSS), and the eROSITA instrument on IKI and DLR’s Spektr-RG space observatory. Besides ESO’s VLT, the follow-up observations were conducted with the Southern Astrophysical Research Telescope (SOAR), the W. M. Keck Observatory, and NASA’s Neil Gehrels Swift Observatory and Chandra X-ray Observatory.



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Bedtime battles: 1 in 4 parents say their child can’t go to sleep because they’re worried or anxious

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Many bedtime battles stem from children’s after dark worries, suggests a new national poll.

And while most families have bedtime rituals to help their little ones ease into nighttime, many rely on strategies that may increase sleep challenges long term, according to the University of Michigan Health C.S. Mott Children’s Hospital National Poll on Children’s Health.

Overall, one in four parents describe getting their young child to bed as difficult — and these parents are less likely to have a bedtime routine, more likely to leave on a video or TV show, and more likely to stay with their child until they’re asleep.

“Our report reinforces the common struggle of getting young children to sleep. When this transition to bedtime becomes a nightly conflict, some parents may fall into habits that work in the moment but could set them up for more sleep issues down the road,” said Mott Poll co-director Sarah Clark, M.P.H.

“Establishing a consistent bedtime routine is crucial. When children don’t get enough rest, it can impact their physical development, emotional regulation and behavior.”

Nearly one in five parents say they have given their kids melatonin to help with sleep while a third stay in the room until their child completely dozes off, according to the nationally representative poll that includes responses from 781 parents of children ages one to six surveyed in February.

Nighttime worries interfere with sleep

Parents share common reasons behind bedtime struggles, with nearly a quarter saying their child’s sleep is often or occasionally delayed due to being worried or anxious.

A particular challenge, parents say, is when children don’t stay asleep. More than a third of parents say their child wakes up upset or crying, with more than 40% saying their child moves to their parents’ bed and about 30% saying children insist that the parent sleep in their room.

“Many young children go through stages when they become scared of the dark or worry that something bad might happen, causing them to delay bedtime or become distressed by parents leaving the room. Bad dreams or being awakened in the middle of the night can also disrupt sleep,” Clark said.

“Although this is a normal part of a child’s development, it can be frustrating when parents already feel tired themselves at the end of the day. Parents should find a balance between offering reassurance and comfort while maintaining some boundaries that help ensure everyone — both kids and adults — get adequate sleep.”

More findings from the report, plus Clark’s recommendations for helping young children fall and stay asleep:

Stick to a regular bedtime routine

Most parents polled report having a bedtime routine for their child, often including brushing teeth, reading bedtime stories and/or bathing. Less than half also say their child has a drink of water or snack, turns off devices, prays and talks about their day.

Other bedtime habits include holding a blanket or stuff animal or sucking a pacifier or fingers.

Not only does having a consistent bedtime routine help make the nighttime transition smoother, Clark says, it also provides one-on-one time, allowing the child to get their parent’s full attention.

“A predictable bedtime routine provides a sense of security and comfort and signals to the child that it’s time to slow down,” she said.

“Knowing what to expect next can reduce anxiety and help children feel safe and relaxed. Having this dedicated time with parents also promotes bonding and emotional connection, creating positive associations with bedtime.”

Nearly two-thirds of parents also said children staying up to play was a major factor in delaying sleep. Clark says, highlighting the need to wind down at least an hour before bed.

Promote an environment conducive to sleep

A little less than half of parents polled say their child sleeps in their own bedroom while less than a quarter share a bedroom with siblings or in the parents’ bedroom. One in 10 kids spend part the night in their own bedroom and part of the night with parents.

More than two-fifths of parents polled said noise from other rooms interfered with their child’s sleep.

“The sleep environment can have a major effect on a child’s sleep quality, including getting to sleep and staying asleep through the night,” Clark said.

“When possible, children should have their own bed in a room that is quiet, without a lot of noise from other family members.”

Many parents polled also use a nightlight or crack the bedroom door so the child isn’t in complete darkness, Clark says, but parents should make sure the light does not shine directly at the child’s face.

Some parents also play calming music or stories to help their child go to sleep, while others use a white noise machine or app. However, Clark cautions to keep white noise machines at no more than 50 decibels and placed at least seven feet from the child’s bed to prevent unintended damage to the child’s hearing.

Talk to a doctor before using aids like melatonin

Many types of melatonin products are advertised as being appropriate for children but these products have not undergone rigorous testing for safety and effectiveness, and their side effects and long term impact on a child’s growth and development are unknown, Clark says.

“Although melatonin is a natural hormone that regulates sleep-wake cycles and may be fine to use occasionally, parents shouldn’t rely on it as a primary sleep aid,” Clark said.

“Parents who are considering giving melatonin to their young child should consult with their pediatrician to discuss options and rule out other causes of sleep problems first.”

If using melatonin, parents should also start with the lowest dose possible.

In addition, it’s important to keep electronics such as tablets or televisions out of children’s bedroom, as the blue light emitted by many of these screens interferes with the natural production of melatonin.

Offer comfort but enforce boundaries

Parents can help ease little ones’ anxiety by allowing extra time to let them talk about their day, which might draw out specific worries and give parents a chance to provide compassion and reassurance, Clark said.

Rather than remaining in the room, parents can also offer to check on the child every few minutes, which acknowledges the child’s fears and offers a reassuring presence, but still maintains a calm sleep environment and promotes sleep independence.

“Families can incorporate comforting rituals to help transform nighttime fears into a calming experience,” Clark said.

Have a consistent approach when children wake up in the night

Some children are prone to vivid dreams or nightmares and may have difficulty getting back to sleep. Parents should decide on their approach to this situation and stick with it, Clark says, whether it’s taking the child back to bed or allowing them to stay in the parents’ room.

“Being consistent in carrying out that approach will help the child adjust and be more likely to return to sleep,” Clark said.

Ease into changes in sleep patterns, such as dropping naps

For young children, a major sleep-related transition is discontinuing daytime naps. In general, children ages one to two should get 11-14 hours of sleep with naps while the amount of recommended sleep decreases slightly from ages three to six.

If children are taking longer to fall asleep at nap time, resisting naps or suddenly having difficulty falling asleep at night or waking up earlier than usual in the morning, it may be time to drop the nap, Clark says.

“Parents may need to adjust sleep routines gradually to transition to changes to a child’s sleep patterns,” Clark said.

Other changes that can affect a child’s sleep include transitioning from a crib to a toddler bed, starting school, having a change in their daytime routine, or being outdoors for longer than usual.



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