It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, November 13, 2024
Extreme weather accelerates nitrate pollution in groundwater
Heavy rains can cause contamination in just 10 days
University of California - Davis
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UC Davis researchers insert a device that continuously collects water samples underground, providing real-time data on nitrate contaminant movement.
Extreme weather spurred by climate change, including droughts and heavy rains, may increase the risk of nitrates from fertilizers ending up in groundwater, according to a recent study from researchers at the University of California, Davis. The study found heavy rains after a drought caused nitrates to seep 33 feet under farm fields in as little as 10 days. The study was published in Water Resources Research.
“The conventional wisdom was that it could take several weeks to years for nitrates to move from the crop root zones to reach groundwater,” said corresponding author Isaya Kisekka, a professor in the Departments of Land, Air and Water Resources and Biological and Agricultural Engineering. “We found these extreme events, such as California’s atmospheric rivers, are going to move nitrate more quickly.”
In this study, different methods were used to measure how much nitrate, a component of nitrogen fertilizer, was seeping down through the soil in a tomato and cucumber crop near Esparto, California. Scientists conducted their research from 2021 until 2023 when California was experiencing periods of drought followed by atmospheric rivers. They measured nitrate during both the growing seasons and the rainy seasons.
Drought can leave more nitrogen in soil
Previous studies have shown about 40% of nitrogen fertilizer used for vegetables isn’t absorbed by the plants but remains in the soil. During droughts, crops don’t use nitrogen efficiently, leading to excess nitrogen in the soil. This study found that if a drought is then followed by heavy rainfall, that sudden burst of water causes nitrate to seep in groundwater more quickly. The nitrate concentration in the shallow groundwater exceeded the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter for drinking water.
“In California, we often say we swing between droughts and floods,” said Kisekka. “These extreme events that come with climate change are going to make the risk of these chemicals ending up in our drinking water much more severe.”
Groundwater is the primary source of drinking water for most of California’s Central Valley. In some regions, such as the Tulare Lake Basin, nearly one-third of drinking and irrigation wells exceed the EPA’s safe nitrate level. High nitrate levels in drinking water can increase health risks, especially for young children. It may also increase the risk of colorectal cancer.
Need for real-time soil nitrate monitoring
Central Valley farmers are required to report to the Regional Water Board how much nitrogen they applied to their field and how much was removed as part of the crop’s yield. The study compared different ways of monitoring when nitrate from fertilizers seep into groundwater. Kisekka said the results highlight the need for affordable, real-time soil nitrate monitoring tools to help farmers manage fertilizer use efficiently.
By using conservation practices that limit leftover nitrates in the crop’s root zone after harvest, farmers can help reduce nitrate contamination in groundwater.
This study's data will also help improve a model called SWAT, which is used to track nitrate seepage into groundwater across California's Central Valley. This effort is part of the Central Valley Water Board’s program to regulate irrigated farmlands.
Other UC Davis authors include Iael Raij Hoffman, Thomas Harter and Helen Dahlke.
The study was supported by the USDA Natural Resource Conservation Service through its Conservation Effects Assessment Project. The national project is designed to assess the effectiveness of conservation practices across different watersheds. The study also had support from the USDA National Institute of Food and Agriculture.
Assessing Nitrate Leaching During Drought and Extreme Precipitation: Exploring Deep Vadose‐Zone Monitoring, Groundwater Observations, and Field Mass Balance
Lehigh partners with North Carolina A&T to enhance flood damage mapping with AI and advanced radar
Universities to collaborate in National Science Foundation-funded effort to transform flood damage assessments through the agency’s “HBCU Excellence in Research” program
Lehigh University
One only needs to glance at the news, social media, or even just out the window to understand the devastation caused by flooding. Recent back-to-back major hurricanes have brought catastrophic rainfall that has devastated communities across the southeastern United States.
With climate change, experts predict these extreme weather events will increasingly become the norm. Among the many ways that researchers are devising strategies to protect and assist vulnerable areas, one such effort involves increasing the speed and accuracy of damage assessments.
“Research shows that if you can save a single day in the initial response phase, it could save thousands of days in the recovery phase because the effect is logarithmic,” says Lehigh University researcher Maryam Rahnemoonfar, an associate professor of computer science and engineering with a joint appointment in the Department of Civil and Environmental Engineering.
This collaboration between Lehigh and NCAT grew out of efforts within Lehigh's Interdisciplinary Research Institutes (IRIs) to foster cross-institutional partnerships that address critical challenges.
A ‘more comprehensive picture’ of disaster zones
Current post-disaster damage assessments typically rely on data from time-consuming manual methods, like ground-based gauges, and remote sensing technologies, such as satellite imagery. Although useful, such tools are localized and provide only a fragmented view of affected areas. They also lack multi-resolution data.
“Optical imagery doesn’t allow you to see below the surface, so you can miss critical information about what’s under the water, like roads and bridges,” says Rahnemoonfar. “But with radar sensors, you can detect submerged objects and get a more comprehensive picture.”
The team will combine multi-modal data sources—including satellite, UAV (unmanned aerial vehicle), and various remote-sensing technologies, such as optical, SAR (Synthetic Aperture Radar), and LiDAR (Light Detection and Ranging)—into a novel framework that automatically extracts spatial and temporal features from these data streams. And they’ll combine all of that with an innovative vision language model that the Lehigh team led by Rahnemoonfar will create.
“Vision language models will be built into a flying or ground-based robot that a response team can communicate with,” she says. “First responders might ask questions like, ‘What roads are flooded?’ or ‘Which neighborhoods are under water?’ and based on the robot’s answer, the team could more efficiently allocate their resources. We’re combining the language and visual domains.”
Rahnmoonfar has developed such models in the past for RGB sensors, but the algorithms that powered them are fully supervised, meaning they require a huge amount of labeled training data in order to identify and learn patterns. Her team will develop a self-supervised algorithm that requires far less data and will use information from their multi-modal data sources and from previous floods.
“Ultimately, we want to develop a system that can assist the rapid response and recovery required after weather disasters,” she says.
Lehigh’s IRIs: Seeding collaborations
The partnership between Lehigh and NCAT was initially facilitated by a seed grant from the Institute for Data, Intelligent Systems, and Computation (I-DISC), one of Lehigh’s three Interdisciplinary Research Institutes (IRIs)
“The goal of all Lehigh’s IRIs is to bring faculty from different areas of expertise and different backgrounds together to address major societal problems,” says Himanshu Jain, T.L. Diamond Distinguished Chair in Engineering and Applied Science and a professor of materials science and engineering. Jain recently stepped down as inaugural director of Lehigh’s Institute for Functional Materials and Devices (I-FMD), a role he held since 2018.
In his capacity as a faculty member, Jain has worked with HBCUs for the past 20 years—including a teaching stint at Tuskegee University—and through his work with I-FMD, he connected with Lehigh alum Jagannathan Sankar '83 PhD, a distinguished professor in NCAT’s Department of Mechanical Engineering.
“NCAT’s researchers are highly regarded,” says Jain, “and through our connection with Professor Sankar, we started developing ideas around how we could bring our faculty together.”
The discussions eventually led to Jain organizing “seed interactions”—virtual meetings where faculty from both institutions could brainstorm possible collaborations. Jain also established seed funding within Lehigh’s IRIs to help potential ideas get off the ground.
As a participant in these meetings, Rahnemoonfar met a colleague at NCAT, Leila Hashemi Beni, an associate professor in the Department of Built Environment, whose research area and interests complemented her own. With the seed funding, Rahnemoonfar and Beni were able to refine the idea that eventually led to the funded NSF award.
“What we wanted to demonstrate with these seed interactions is that they’re effective and lead to fruitful collaboration,” says Jain. “It’s the beginning of what we want to establish as a track record of our institutions successfully working together. What we ultimately want from the IRIs is for them to help incubate focused research centers devoted to addressing big, consequential societal issues. With NCAT, we are not only technically interested in each other’s expertise, but we have a scientific synergy that can have a significant impact on some of the world’s biggest problems.”
Most surveyed grocery shoppers report noticing shrinkflation
Fewer consumers check key indicators like unit price and weight compared to total cost
Purdue University
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Bar graph display the rate of household food insecurity by households with children between January 2022 and October 2024. Credit: Purdue University's Center for Food Demand Analysis and Sustainability
Credit: Purdue University's Center for Food Demand Analysis and Sustainability
WEST LAFAYETTE, Ind. — Over three-quarters of surveyed consumers say they have noticed shrinkflation at the grocery store in the previous 30 days, according to the October 2024 Consumer Food Insights Report(CFI).
The survey-based report out of Purdue University’s Center for Food Demand Analysis and Sustainability(CFDAS) assesses food spending, consumer satisfaction and values, support of agricultural and food policies, and trust in information sources. Purdue experts conducted and evaluated the survey, which included 1,200 consumers across the U.S.
The latest CFI survey included questions about product information that consumers most look for when buying food at the store. The survey showed that 82% of consumers “often” or “always” check the price of food items before buying.
Fewer consumers “often” or “always” check for unit price (51%) or weight (44%). “The unit price and weight in particular are key indicators of shrinkflation. Without checking weight or unit price, consumers may not notice reductions in the quantity or value of their typical grocery products,” Balagtas said.
Most consumers (82%) think shrinkflation is a common practice used by food companies and 76% believe it is a result of trying to increase profits even when costs are not rising.
“It is interesting yet not entirely surprising to see this sentiment as articles about grocery prices, accusations of corporate greed and shrinkflation continue to circulate in popular news media,” Balagtas said. National Public Radio and USA Today, for example, both covered the topic in September.
“Our research on food values shows that price and affordability are among the top concerns for food shoppers, and one way for food manufacturers to reduce the price is to reduce the size of a product. But reducing product size could cause consumer resentment,” he said. Around 74% of consumers agree there should be requirements in place that make product size reductions more transparent to the consumer, such as prominent labeling.
Food satisfaction remained high among most American adults, with 69% of consumers classified as “thriving” on the diet well-being index. Food insecurity remained unchanged from last month at 13%.
“Notably, households with children are more likely to experience food insecurity, with 17% of consumers in these households reporting difficulties accessing adequate amounts of nutritious foods,” said Elijah Bryant, a survey research analyst at CFDAS and a co-author of the report. Households without children report a lower food insecurity rate (13%).
Questions about consumer awareness, experience and perceptions of shrinkflation were new to the CFI survey. With shrinkflation, food companies reduce the quantity or size of a food product while keeping the same price.
“A variety of factors may influence a producer’s decision to downsize a product’s size, such as rising costs in the supply chain and inflationary pressures,” said the report’s lead author, Joseph Balagtas, professor of agricultural economics at Purdue and director of CFDAS. “The goal is to better understand how consumers perceive these reductions and if they have noticed them happening at all.”
The new CFI survey sorted consumer responses into two groups: households with children and those without children. Of the consumers who noticed shrinkflation, 78% say they have observed it in snack foods and 53% in packaged desserts and sweets. Just under half, 48%, also said they have observed shrinkflation in frozen foods. Those with children report seeing shrinkflation in a wider variety of food products.
The CFDAS researchers saw no significant changes in consumer estimates of food inflation (5.4%) or expectations for future food inflation (3%). Overall weekly food spending rose to $197 per week, 5.9% higher than this time last year and 11.2% higher than two years ago.
“Households with children report eating more meals from restaurants, fast food places or cafeterias than households without children, and much of their budget for food away from home goes toward delivery or takeout options,” Bryant said.
“Consumers living with children report choosing foods that are commonly labeled as ‘sustainable’ or ‘ethical,’ such as wild-caught fish, cage-free eggs, plant-based proteins or organic foods more frequently than childless adults,” Bryant said. Similarly, those with children tend to check labels for food origin, recalls, genetically modified organism ingredients or natural/clean labels.
“Somewhat surprisingly, consumers with children in their households report engaging in risky food behaviors — eating rare meat, unwashed produce or raw dough, for example,” Bryant said. Consumers with children are also more likely to throw away food that is past the use-by date.
“The largest differences we observe between households with and without children come in the agreement with health-related claims,” Bryant said. Those with children are more likely to agree that organic food is more nutritious and that both gluten-free food and plant-based milk are healthier.
“Consumer beliefs about these statements and the frequency at which consumers report choosing these nonconventional foods when grocery shopping suggest that those with children are a potential target demographic for food companies looking to bring alternative, health and sustainability-focused foods to market,” Bryant noted.
The Center for Food Demand Analysis and Sustainability is part of Purdue’s Next Moves in agriculture and food systems and uses innovative data analysis shared through user-friendly platforms to improve the food system. In addition to the Consumer Food Insights Report, the center offers a portfolio of online dashboards.
About Purdue Agriculture
Purdue University’s College of Agriculture is one of the world’s leading colleges of agricultural, food, life and natural resource sciences. The college is committed to preparing students to make a difference in whatever careers they pursue; stretching the frontiers of science to discover solutions to some of our most pressing global, regional and local challenges; and, through Purdue Extension and other engagement programs, educating the people of Indiana, the nation and the world to improve their lives and livelihoods. To learn more about Purdue Agriculture, visit this site.
About Purdue University
Purdue University is a public research institution demonstrating excellence at scale. Ranked among top 10 public universities and with two colleges in the top four in the United States, Purdue discovers and disseminates knowledge with a quality and at a scale second to none. More than 105,000 students study at Purdue across modalities and locations, including nearly 50,000 in person on the West Lafayette campus. Committed to affordability and accessibility, Purdue’s main campus has frozen tuition 13 years in a row. See how Purdue never stops in the persistent pursuit of the next giant leap — including its first comprehensive urban campus in Indianapolis, the Mitch Daniels School of Business, Purdue Computes and the One Health initiative — at https://www.purdue.edu/president/strategic-initiatives.
Writer: Steve Koppes
Method of Research
Survey
Subject of Research
People
Article Title
Consumer Food Insights Report October 2024
Article Publication Date
13-Nov-2024
The secrets of fossil teeth revealed by the synchrotron: a long childhood is the prelude to the evolution of a large brain
Could social bonds be the key to human big brains?
European Synchrotron Radiation Facility
video:
3D reconstruction of the fossil skull of the sub-adult early Homo from the Dmanisi site in Georgia. The green, orange and red colors represent the preserved teeth (imaged respectively with the synchrotron at 5um, with the synchrotron at 47um, and with an industrial scanner at 250um). The blue teeth are missing ones added by mirroring their symmetrical counterparts. The purple first lower incisors have not been recovered, and have been extrapolated form the second lower incisor. Then the right upper canine is showed at 5um resolution to illustrate the visibility of growth lines on its surface, as well as on virtual slices in its enamel and dentine. A second level of zoom is done to reach the 0.7umm resolution that shows the daily lines increments in enamel. All the teeth are then virtually extracted from the skull and disposed in order to show the final dentition state at the death of this individual. Based on the dental increments observed in all the teeth, a virtual growth series has been computed every 6 months from the birth to the death of this sub-adult individual that occurred at 11.42 years.
Credit: Credit: ESRF/Paul Tafforeau, Vincent Beyrand
The secrets of fossil teeth revealed by the synchrotron: a long childhood is the prelude to the evolution of a large brain
Could social bonds be the key to human big brains? A study of the fossil teeth of early Homo from Georgia dating back 1.77 million years reveals, thanks to the European Synchrotron (ESRF) in Grenoble, a prolonged childhood despite a small brain and an adulthood comparable to that of the great apes. This discovery suggests that an extended childhood, combined with cultural transmission in three-generation social groups, may have triggered the evolution of a large brain like that of modern humans, rather than the reverse. The study is published in Nature.
Summary
An international team of researchers from the University of Zurich (Switzerland), the European Synchrotron Radiation Facility (ESRF, Grenoble, France), and the Georgian National Museum (Georgia) has challenged the hypothesis that the long childhood of modern humans (Homo sapiens) is linked to their big brains, by studying a fossil of early Homo from Georgia dating back 1.77 million years. Using synchrotron imaging to analyse the dental development of an almost adult individual, the scientists observed that although this species reached adulthood as quickly as the great apes (around 12 years), it exhibited a sequence of tooth development similar to that of modern humans, suggesting a longer duration of childhood, and longer dependence on adults, than in the great apes.
Because the brain of early Homo was only slightly larger than that of a chimpanzee, the researchers hypothesise that this slower development was linked to the intensified cultural transmission across the generations, where the elders pass on their knowledge to the young. A longer childhood in a three-generation social context would have enabled immature group members to assimilate a growing amount of knowledge more effectively. Once this evolutionary process had been set in motion, natural selection would have acted on the traits that made cultural transmission within social groups increasingly efficient. Only in a second phase, and with increasing social information transfer, evolution would have favoured the development of ever-larger brains, which would have led to the late adulthood and long life spans characteristic of modern humans. This study published in Nature demystifies the role of large brains for the evolution of a long childhood, suggesting instead that the long childhood together with the three-generation social structure eventually led to larger brains.
Full text
Compared to the great apes, humans have an exceptionally long childhood, during which parents, grandparents and other adults contribute to their physical and cognitive development. This is a key developmental period for acquiring all the cognitive skills needed in the complex social environment of a human group. The current consensus is that the very long growth of modern humans has evolved as a consequence of the increase in brain volume, since such an organ requires significant energy resources to grow. However, the ‘big brain - long childhood’ hypothesis may need to be revised, as shown by an international team of researchers in the journal Nature, based on an analysis of the dental growth of an exceptional fossil.
Teeth are the key
The research team, made up of scientists from the University of Zurich (Switzerland), the European Synchrotron Radiation Facility (ESRF, Grenoble, France), and the Georgian National Museum (Georgia), used synchrotron imaging to study the dental development of a near-adult fossil of early Homo from the Dmanisi site in Georgia, dated to around 1.77 million years ago.
“Childhood and cognition do not fossilise, so we have to rely on indirect information. Teeth are ideal because they fossilise well and produce daily rings, in the same way that trees produce annual rings, which record their development”, explains Christoph Zollikofer from the University of Zurich and first author of the publication. “Dental development is strongly correlated with the development of the rest of the body, including brain development. Access to the details of a fossil hominid's dental growth therefore provides a great deal of information about its general growth”, adds Paul Tafforeau, scientist at the ESRF and co-author of the study.
18 years of research
The project was launched in 2005, following the initial success of non-destructive analyses of dental microstructures using phase contrast synchrotron tomography at the ESRF. This technique enabled scientists to create virtual microscopic slices through the teeth of this fossil. The exceptional quality of preservation of the growth structures in this specimen has made it possible to reconstruct all the phases of its dental growth, from birth to death, with unprecedented precision. In a way, the scientists have virtually regrown the teeth of this hominid.
This project took almost 18 years from its initial conception in 2005 to the finalisation of the results in 2023. The scientists scanned the teeth for the first time in 2006, and the first results on the fossil’s age at death were obtained in 2007.
“We expected to find either dental development typical of early hominids, close to that of the great apes, or dental development close to that of modern humans. When we obtained the first results, we couldn’t believe what we saw, because it was something different that implied faster molar crown growth than in any other fossil hominin or living great ape”, explains Paul Tafforeau. Over the next few years, five series of experiments and four complete analyses using different approaches were carried out as technical advances were made in dental synchrotron imaging. With the results all pointing in the same direction, and potentially having a strong impact on the ‘big brain - long childhood’ hypothesis, the scientists had to think outside the box to understand this fossil. “It's been a slow maturation, both technically and intellectually, to finally arrive at the hypothesis we are publishing today” concludes Paul Tafforeau.
Milk teeth used for longer
“The results showed that this individual died between 11 and 12 years of age, when his wisdom teeth had already erupted, as is the case in great apes at this age,” explains Vincent Beyrand, co-author of the study. However, the team found that this fossil had a surprisingly similar tooth maturation pattern to humans, with the back teeth lagging behind the front teeth for the first five years of their development.
“This suggests that milk teeth were used for longer than in the great apes and that the children of this early Homo species were dependent on adult support for longer than those of the great apes,” explains Marcia Ponce de León from the University of Zurich and co-author of the study. “This could be the first evolutionary experiment of prolonged childhood”.
How teeth can give clues about brain evolution
This is where the ‘big brain - long childhood’ hypothesis is put to the test. Early Homo individuals did not have much bigger brains than great apes or australopithecines, but they possibly lived longer. In fact, one of the skulls discovered at Dmanisi was that of a very old individual with no teeth left during its last few years of life. “The fact that such an old individual was able to survive without any teeth for several years indicates that the rest of the group took good care of him,” comments David Lordkipadnize of the National Museum of Georgia and co-author of the study. The older individuals are the ones with the greatest experience, so it's likely that their role in the community was to pass on their knowledge to the younger individuals. This three-generation structure is a fundamental aspect of the transmission of culture in humans.
It is well known that young children can memorise an enormous amount of information thanks to the plasticity of their immature brains. However, the more there is to memorise, the longer it takes.
This is where the new hypothesis comes in. Children's growth would have slowed down at the same time as cultural transmission increased, making the amount of information communicated from old to young increasingly important. This transmission would have enabled them to make better use of available resources while developing more complex behaviours, and would thus have given them an evolutionary advantage in favour of a longer childhood (and probably of a longer lifespan).
Once this mechanism was in place, natural selection would have acted on cultural transmission and not just to biological traits. Then, as the amount of information to be transmitted increased, evolution would have favoured an increase in brain size and a delay in adulthood, allowing us both to learn more in childhood and to have the time to grow a larger brain despite limited food resources.
Therefore, it may not have been the evolutionary increase in brain size that led to the slowdown in human development, but the extension of childhood and the three-generation structure that favoured bio-cultural evolution. These mechanisms, in turn, led to an increase in brain size, a later adulthood and a longer life span. Studying the teeth of this exceptional fossil could therefore encourage researchers to reconsider the evolutionary mechanisms that led to our own species, Homo sapiens.
3D reconstruction of the fossil skull of the sub-adult early Homo from the Dmanisi site in Georgia. The green, orange and red colors represent the preserved teeth (imaged respectively with the synchrotron at 5um, with the synchrotron at 47um, and with an industrial scanner at 250um). The blue teeth are missing ones added by mirroring their symmetrical counterparts. The purple first lower incisors have not been recovered, and have been extrapolated form the second lower incisor. Credit: ESRF/Paul Tafforeau, Vincent Beyrand
Credit
Credit: ESRF/Paul Tafforeau, Vincent Beyrand
Fossil of the near-adult Homo from the Dmanisi site in Georgia, dated to around 1.77 million years ago, scanned at the European synchrotron (ESRF). Credit: Georgian National Museum
Dental evidence for extended growth in early Homo from Dmanisi
Article Publication Date
13-Nov-2024
Bird brain from the age of dinosaurs reveals roots of avian intelligence
University of Cambridge
image:
A ‘one of a kind’ fossil discovery could transform our understanding of how the unique brains and intelligence of modern birds evolved, one of the most enduring mysteries of vertebrate evolution.
Researchers have identified a remarkably well-preserved fossil bird, roughly the size of a starling, from the Mesozoic Era. The complete skull has been preserved almost intact: a rarity for any fossil bird, but particularly for one so ancient, making this one of the most significant finds of its kind.
A ‘one of a kind’ fossil discovery could transform our understanding of how the unique brains and intelligence of modern birds evolved, one of the most enduring mysteries of vertebrate evolution.
Researchers have identified a remarkably well-preserved fossil bird, roughly the size of a starling, from the Mesozoic Era. The complete skull has been preserved almost intact: a rarity for any fossil bird, but particularly for one so ancient, making this one of the most significant finds of its kind.
The extraordinary three-dimensional preservation of the skull allowed the researchers, led by the University of Cambridge and the Natural History Museum of Los Angeles County, to digitally reconstruct the brain of the bird, which they have named Navaornis hestiae. Navaornis lived approximately 80 million years ago in what is now Brazil, before the mass extinction event that killed all non-avian dinosaurs.
The researchers say their discovery, reported in the journal Nature, could be a sort of ‘Rosetta Stone’ for determining the evolutionary origins of the modern avian brain. The fossil fills a 70-million-year gap in our understanding of how the brains of birds evolved: between the 150-million-year-old Archaeopteryx, the earliest known bird-like dinosaur, and birds living today.
Navaornis had a larger cerebrum than Archaeopteryx, suggesting it had more advanced cognitive capabilities than the earliest bird-like dinosaurs. However, most areas of its brain, like the cerebellum, were less developed, suggesting that it hadn’t yet evolved the complex flight control mechanisms of modern birds.
“The brain structure of Navaornis is almost exactly intermediate between Archaeopteryx and modern birds – it was one of these moments in which the missing piece fits absolutely perfectly,” said co-lead author Dr Guillermo Navalón from Cambridge’s Department of Earth Sciences.
Navaornis is named after William Nava, director of the Museu de Paleontologia de Marília in Brazil’s São Paolo State, who discovered the fossil in 2016 at a site in the neighbouring locality of Presidente Prudente. Tens of millions of years ago, this site was likely a dry area with slow-flowing creeks, which enabled the fossil’s exquisite preservation. This preservation allowed the researchers to use advanced micro-CT scanning technology to reconstruct the bird’s skull and brain in remarkable detail.
“This fossil is truly so one-of-a-kind that I was awestruck from the moment I first saw it to the moment I finished assembling all the skull bones and the brain, which lets us fully appreciate the anatomy of this early bird,” said Navalón.
“Modern birds have some of the most advanced cognitive capabilities in the animal kingdom, comparable only with mammals,” said Professor Daniel Field from Cambridge’s Department of Earth Sciences, senior author of the research. “But scientists have struggled to understand how and when the unique brains and remarkable intelligence of birds evolved—the field has been awaiting the discovery of a fossil exactly like this one.”
Before this discovery, knowledge of the evolutionary transition between the brains of Archaeopteryx and modern birds was practically non-existent. “This represents nearly 70 million years of avian evolution in which all the major lineages of Mesozoic birds originated - including the first representatives of the birds that live today,” said Navalón. “Navaornis sits right in the middle of this 70-million-year gap and informs us about what happened between these two evolutionary points.”
While the skull of Navaornis somewhat resembles that of a small pigeon at first glance, closer inspection reveals that it is not a modern bird at all but instead a member of a group of early birds named enantiornithines, or the ‘opposite birds.’
‘Opposite birds’ diverged from modern birds more than 130 million years ago, but had complex feathers and were likely competent flyers like modern birds. However, the brain anatomy of Navaornis poses a new question: how did opposite birds control their flight without the full suite of brain features observed in living birds, including an expanded cerebellum, which is a living bird’s spatial control centre?
“This fossil represents a species at the midpoint along the evolutionary journey of bird cognition,” said Field, who is also the Strickland Curator of Ornithology at Cambridge’s Museum of Zoology. “Its cognitive abilities may have given Navaornis an advantage when it came to finding food or shelter, and it may have been capable of elaborate mating displays or other complex social behaviour.”
“This discovery shows that some of the birds flying over the heads of dinosaurs already had a fully modern skull geometry more than 80 million years ago,” said co-lead author Dr Luis Chiappe from the Natural History Museum of Los Angeles County.
While Navaornis is one of the best-preserved bird fossils ever found from the Mesozoic Era, the researchers believe many more finds from the Brazilian site where it was found could offer further insights into bird evolution.
“This might be just one fossil, but it’s a key piece in the puzzle of bird brain evolution,” said Field. “With Navaornis, we’ve got a clearer view of the evolutionary changes that occurred between Archaeopteryx and today’s intelligent, behaviourally complex birds like crows and parrots.”
While the discovery is a significant breakthrough, the researchers say it is only the first step in understanding the evolution of bird intelligence. Future studies may reveal how Navaornis interacted with its environment, helping to answer broader questions about the evolution of bird cognition over time.
Navaornis is the most recent in a quartet of Mesozoic fossil birds described by Field’s research group since 2018, joining Ichthyornis, Asteriornis (the ‘Wonderchicken’), and Janavis. The group’s work on new fossil discoveries combined with advanced visualisation and analytical techniques have revealed fundamental insights into the origins of birds, the most diverse group of living vertebrate animals.
The research was supported in part by UK Research and Innovation (UKRI). Daniel Field is a Fellow of Christ’s College, Cambridge.
A ‘one of a kind’ fossil discovery could transform our understanding of how the unique brains and intelligence of modern birds evolved, one of the most enduring mysteries of vertebrate evolution.
Researchers have identified a remarkably well-preserved fossil bird, roughly the size of a starling, from the Mesozoic Era. The complete skull has been preserved almost intact: a rarity for any fossil bird, but particularly for one so ancient, making this one of the most significant finds of its kind.
Credit
Guillermo Navalón
Skeleton of Navaornis, a fossil bird from the age of dinosaurs.
Credit
Stephanie Abramowicz
Navaornis fills a ~70-million-year gap in our knowledge of the evolution of the unique bird brain. Navaornis hestiae (centre) documents a previously unknown intermediate stage in the evolution of the central nervous system between the earliest birds (e.g., Archaeopteryx, left) and living birds (e.g., Tangara seledon, right). Artwork from Júlia d’Oliveira.
