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, June 22, 2022
Chinese scientists help Africa combat land degradation
PAGGW National 30-m spatial resolution LPD Product. Credit: AIR
Chinese scientists released an online tool, the Great Green Wall Big Data Facilitator, to help African countries combat increasingly severe land degradation on June 16, the 28th World Day to Combat Desertification & Drought.
Land degradation is one of the most significant global ecological and environmental challenges. Africa is particularly vulnerable to land degradation and desertification, and it is the most severely affected region. "Up to 65 percent of productive land is degraded, while desertification affects 45 percent of Africa's land area," according to a report of FAO in 2021.
In the United Nations 2030 Agenda for Sustainable Development (the UN 2030 Agenda), UN has described 17 Sustainable Development Goals (SDGs), among which SDG 15 proposes a prospect of "By 2030, combat desertification, restore degraded land and soil, including land affected by desertification, drought, and floods, and strive to achieve a land degradation-neutral world."
To address the data gap in the global land degradation monitoring, a group of Chinese scientists led by Prof. Li Xiaosong from the International Research Center of Big Data for Sustainable Development Goals (CBAS) and the Aerospace Information Research Institute (AIR), Chinese Academy of Sciences (CAS), in partnership with Beijing Normal University, Computer Network Information Center of CAS and Institute of Software of CAS, have developed a 30-meter Land Productivity Dynamics (LPD) calculation tool.
As the world's first 30-meter LPD calculation tool, it can realize the calculation of a 30-meter LPD within the specified global spatial range as well as time period, thereby providing important data support for global land degradation monitoring.
The calculation is built on the SDG Big Data Platform supported by CBAS, which was launched in Beijing in September 2021 to facilitate the implementation of the UN 2030 Agenda.
The "Great Green Wall" is an African-led initiative launched in 2007 with the goal to restore the continent's degraded landscapes and transform millions of lives in the Sahel. To support the development of "Great Green Wall," Chinese scientists use this tool to produce a 30-meter spatial resolution LPD product which covers an area of 9.34 million square kilometers in 11 member countries of the Pan Africa Agency of the Great Green Wall (PAGGW).
The spatiotemporal analysis result shows that from 2013 to 2020, for the PAGGW countries, the land with increasing productivity accounted for 16.25%, and the area with decreasing productivity accounted for 7.36% of the total area.
For the Sahel, the main target area of the Great Green Wall, the land with increasing productivity accounted for 8.45%, while the land with decreasing productivity accounting for 9.24% of the total area, which is not a promising prospect for the development of the Great Green Wall.
The LPD product presented on the Great Green Wall Big Data Facilitator can be used to track the progress of LDN of the target areas. In addition, the platform also provides a knowledge bank about prevention and control of land degradation, which is obtained from successful practices of China's efforts to combat land degradation in Northern China.
Ibrahim Thiaw, Deputy Secretary-General of the U.N. and Executive Secretary of United Nations Convention to Combat Desertification (UNCCD) applauded the launch of this online tool, saying that the results have the potential to facilitate the Great Green Wall of Africa in the future.Image: Desert greenery
Researchers from the Institute of Industrial Science, The University of Tokyo, find that the risk of human—elephant conflict in Thailand is likely to shift with climate change. ]Credit: Institute of Industrial Science, The University of Tokyo
As natural areas become increasingly fragmented, the potential for humans and wildlife to interact is growing. Now, researchers from Japan have found that climate change is altering the risk of such interactions.
In a recent study published in Science of the Total Environment, researchers from the Institute of Industrial Science, The University of Tokyo, examined how the risk of human–elephant conflict could change over time. When humans encroach on natural landscapes, the chances of interactions with wildlife increase. Conflicts can arise when wildlife damages livestock or crops, or when human activities damage animal habitat. For example, forest edges are particularly attractive areas for elephants on the hunt for food, which can bring them into contact with mature crops, or with farmers.
"In Thailand, half of the country's population live in rural areas and rely on agriculture," says lead author Nuntikorn Kitratporn. "Thailand also has about three to four thousand wild elephants and deforestation and the growth of commercial agriculture have pushed elephants into increasingly fragmented patches of habitat, increasing the chance of interactions between humans and elephants."
Climate change is bringing additional complexity to these interactions, as changing environmental conditions lead to changes in the behavior and distribution of elephants. In rural areas where people depend on agriculture to survive, human–elephant conflict may well intensify in the future. To assess the risk of this, the researchers used a risk framework that incorporated different possible scenarios. They used this framework to examine the recent spatial distribution of human–elephant conflict (2000–2019) in Thailand and how it may look in the near future (2024–2044). Different projections of future climate and socioeconomic conditions were incorporated into the framework and the effects on land use were examined.
"We found a spatial shift in risk toward northern areas and higher latitudes," says Kitratporn. "In other areas, habitat is likely to become less suitable over time, which could first increase and gradually decrease the risk of interactions."
Understanding how human–wildlife interactions may change in the future is vital for long-term planning. The results from this study could be used to develop planning strategies in affected communities and raise awareness of ways in which humans and wildlife can coexist.High risk of conflict between humans and elephants and lions
More information:Nuntikorn Kitratporn et al, Human-elephant conflict risk assessment under coupled climatic and anthropogenic changes in Thailand,Science of The Total Environment(2022).DOI: 10.1016/j.scitotenv.2022.155174
Honey bees feed on imidacloprid during a cage experiment. Credit: Mohamed Alburaki, ARS
Winter honey bees, compared to newly emerged summer bees, have a better ability to withstand the harmful effects of a widely-used insecticide in pest management, according to a recent study published in Apidologie.
United States Department of Agriculture (USDA), Agricultural Research Service (ARS) researchers from the Bee Research Laboratory in Beltsville, Maryland, found winter honey bees' consumption of a nearly lethal, imidacloprid-laced syrup did not affect their survival during the study.
Imidacloprid is an insecticide made to mimic nicotine and is toxic to insects. This powerful insecticide is widely used in agriculture for pest management control. Honey bees are likely to encounter imidacloprid while foraging in the field or through contaminated hive products.
"Although imidacloprid toxicity to honey bees is an important concern for beekeepers, our results provide good news," said Miguel Corona and Mohamed Alburaki, researchers at the ARS Bee Research Laboratory. "Our research shows that winter honey bees have unrecognized physiological mechanisms to counteract the effects of insecticides."
The study assessed differences in diet behaviors for summer and winter honey bees in a controlled laboratory setting. Researchers provided sublethal doses of the imidacloprid-laced syrup to bees as necessary. Winter bees showed a preference to consuming imidacloprid-laced syrup over untreated sugar syrup while summer honey bees made the safe choice and avoided consuming the laced syrup each time.
According to Corona, it is important to study the differences of summer and winter honey bees' diets. Honey bee colonies survive extreme seasonal differences in temperature and forage by producing two seasonal phenotypes of workers: summer and winter bees. These seasonal phenotypes differ significantly in their psychological characteristics as well as their susceptibility to disease and ability to handle poisonous substances.
"Winter bees and summer bees undergo physiological changes to cope with drastic seasonal changes in temperature and the availability of nutritional resources," said Corona and Alburaki. "Our results suggest that long-lived winter bees are especially well-adapted to tolerate higher levels of chemical stressors."
More information:Mohamed Alburaki et al, Influence of honey bee seasonal phenotype and emerging conditions on diet behavior and susceptibility to imidacloprid,Apidologie(2022).DOI: 10.1007/s13592-022-00922-9
Dead oysters seen along a shoreline in Washington state, following a record heat wave in summer 2021. Credit: Blair Paul
It's hard to forget the excruciating heat that blanketed the Pacific Northwest in late June 2021. Temperatures in Oregon, Washington and British Columbia soared to well above 100 degrees Fahrenheit, with Seattle setting an all-time heat record of 108 degrees on June 28.
During the heat wave, also called a heat dome, scientists and community members alike noticed a disturbing uptick of dying and dead shellfish on some beaches in Washington and British Columbia, both in the Salish Sea and along the outer coast. The observers quickly realized they were living through an unprecedented event and they organized to document the shellfish die-offs as they happened in real time.
Now, a team led by the University of Washington has compiled and analyzed hundreds of these field observations to produce the first comprehensive report of the impacts of the 2021 heat wave on shellfish. The researchers found that many shellfish were victims of a "perfect storm" of factors that contributed to widespread death: The lowest low tides of the year occurred during the year's hottest days—and at the warmest times of day. The results were published online June 20 in the journal Ecology.
"You really couldn't have come up with a worse scenario for intertidal organisms," said lead author Wendel Raymond, a research scientist at UW Friday Harbor Laboratories. "This analysis has given us a really good general picture of how shellfish were impacted by the heat wave, but we know this isn't even the full story."
The research team leveraged existing collaborations across tribes, state and federal agencies, academia and nonprofits. They devised a simple survey and five-point rating system (1 = much worse than normal to 5 = much better than normal) and asked participants to provide ratings based on their knowledge of a species in that location. In total, they gathered 203 observations from 108 unique locations, from central British Columbia down to Willapa Bay, Washington.
Joe Williams, front, and Darrell Williams with the Swinomish Indian Tribal Community’s Fisheries Department dig clams on a beach in Skagit Bay as part of a survey that is conducted to estimate clam biomass. Credit: Northwest Indian Fisheries Commission
"The strength of this study and what it really highlights is the value of local knowledge and also the importance of understanding natural history," said co-author P. Sean McDonald, a UW associate teaching professor in environmental studies and aquatic and fishery sciences. "This is the first step and a snapshot, if you will, of what shellfish experienced on the beaches during the heat wave."
The researchers found that each species' ecology contributed to its general success or failure to survive the extreme heat. For example, some shellfish that naturally burrow deep beneath the surface, like butter clams, usually fared better than ones that typically ride out low tide just below the sand's surface, such as cockles.
They also found that location mattered. Shellfish on the outer coast experienced low tide about four hours earlier than shellfish on inland beaches. For inland shellfish, low tide—or when the most shellfish were exposed—hit around solar noon, when the sun was directly overhead.
Additionally, air temperatures were much higher at inland sites compared to the outer coast, causing more stress on inland populations. For example, California mussels, found almost exclusively on the outer coast, mostly survived the heat while bay mussels, found in more inner coastal sites, were more likely to die from heat exposure. More water movement and wave action on the outer coast also likely helped lessen the impacts of the heat on shellfish along those beaches.
Many shellfish don't tend to move much on any given beach, so where they naturally live in the intertidal zone also contributed to their success or failure, the researchers found. For example, acorn barnacles that live higher on the shore generally were more impacted than clams and oysters that are lower on the beach and more likely to remain under water.
Julie Barber, senior shellfish biologist with the Swinomish Indian Tribal Community, quantifying recent butter clam deaths on a beach in Skagit Bay, Washington, in July 2021, following a record heat wave. Credit: Northwest Indian Fisheries Commission
"Although this event had negative effects on marine life, there is hope that can be found in this work. Not all locations and species were affected equally, offering clues to pathways to resiliency in the future," said co-author Annie Raymond, a shellfish biologist with Jamestown S'Klallam Tribe.
Perhaps most surprisingly, the researchers noticed interesting patterns in survival rates among shellfish on the same beach. In some locations, shellfish in the path of freshwater runoff on one section of beach survived, while others just a few miles away perished. If a tree hung over part of a beach and shaded the sand, those shellfish generally made it while others didn't. Co-author Julie Barber, senior shellfish biologist with the Swinomish Indian Tribal Community, remembers seeing those patterns while walking the beaches of Skagit Bay, and in some locations, being surrounded by dead cockles in every direction.
"It was pretty unsettling, and I've never seen anything like it," Barber said. She remembers exchanging emails with colleagues from around the region as they noticed similar mass die-offs on their local beaches, then realizing that they urgently needed to coordinate and document what was happening.
"This effort was a beautiful demonstration of how collaborators can come together with one common cause—which in our case was trying to understand what happened to these shellfish," Barber said.
Because the heat wave occurred during the time frame when many shellfish are reproducing, the mass die-offs could impact those populations for at least several years, highlighting the need for long-term monitoring, the researchers said. And as climate change continues to produce more frequent extreme heat events, shellfish deaths like those of last summer may become more of a common reality.
Dead cockles seen on a beach after record heat in July 2021 in Skagit Bay, Washington. Credit: James McArdle
"The Swinomish Indian Tribal Community is proud to be a leader in this important scientific research that assessed in real time the devastating impacts to our shellfish resources from the unprecedented heat dome last summer. Shellfish are a priority first food that our tribal community relies on for spiritual and subsistence nourishment. Last summer's extreme weather event reinforced to us that we must act faster to ensure climate resiliency for our community's long-term health and well-being," said Swinomish Tribal Chairman Steve Edwards.
"Once the effects of the heat wave started to become apparent, the collaboration that emerged was amazing as managers and scientists worked quickly to put together a rapid response to capture information," said co-author Camille Speck, Puget Sound intertidal bivalve manager for Washington Department of Fish and Wildlife. "We still have so much to learn about the effects of the heat wave on Salish Sea marine ecosystems, and more work to do as managers to prepare for the next one and develop informed responses. These conversations are happening now, and it is our hope that we will be better prepared for whatever comes next."
Other co-authors are Megan Dethier of the UW; Teri King of UW-based Washington Sea Grant; Christopher Harley of University of British Columbia; Blair Paul of Skokomish Indian Tribe; and Elizabeth Tobin of Jamestown S'Klallam Tribe. More than two dozen individuals contributed data to this project.Yessotoxins produced by phytoplankton caused summer mass shellfish mortality events in Washington
More information:Wendel W. Raymond et al, Assessment of the impacts of an unprecedented heatwave on intertidal shellfish of the Salish Sea,Ecology(2022).DOI: 10.1002/ecy.3798
Microbes taken from surface sediment near Lost Hammer Spring, Canada, about 900 km south of the North Pole, could provide a blueprint for the kind of life forms that may once have existed, or may still exist, on Mars. Credit: Elisse Magnuson.
The extremely salty, very cold, and almost oxygen-free environment under the permafrost of Lost Hammer Spring in Canada's High Arctic is the one that most closely resembles certain areas on Mars. So, if you want to learn more about the kinds of life forms that could once have existed—or may still exist—on Mars, this is a good place to look. After much searching under extremely difficult conditions, McGill University researchers have found microbes that have never been identified before. Moreover, by using state-of-the-art genomic techniques, they have gained insight into their metabolisms
In a recent paper in The ISME Journal, the scientists demonstrate, for the first time, that microbial communities found living in Canada's High Arctic, in conditions analogous to those on Mars, can survive by eating and breathing simple inorganic compounds of a kind that have been detected on Mars (such as methane, sulfide, sulfate, carbon monoxide, and carbon dioxide). This discovery is so compelling that samples of the Lost Hammer surface sediments were selected by the European Space Agency to test the life detection capabilities of the instruments they plan to use on the next ExoMars Mission.
Developing a blueprint for life on Mars
Lost Hammer Spring, in Nunavut in Canada's High Arctic, is one of the coldest and saltiest terrestrial springs discovered to date. The water which travels up through 600 meters of permafrost to the surface is extremely salty (~24% salinity), perennially at sub-zero temperatures (~−5 °C) and contains almost no oxygen (<1ppm dissolved oxygen). The very high salt concentrations keep the Lost Hammer spring from freezing, thus maintaining a liquid water habitat even at sub-zero temperatures. These conditions are analogous to those found in certain areas on Mars, where widespread salt deposits and possible cold salt springs have been observed. And while earlier studies have found evidence of microbes in this kind of Mars-like environment—this is one of a very few studies to find microbes alive and active
To gain insight into the kind of life forms that could exist on Mars, a McGill University research team, led by Lyle Whyte of the Department of Natural Resource Sciences, has used state-of-the-art genomic tools and single cell microbiology methods to identify and characterize a novel, and more importantly, an active microbial community in this unique spring. Finding the microbes and then sequencing their DNA and mRNA was no easy task.
It takes an unusual life form to survive in difficult conditions
"It took a couple of years of working with the sediment before we were able to successfully detect active microbial communities," explains Elisse Magnuson, a Ph.D. student in Whyte's lab, and the first author on the paper. "The saltiness of the environment interferes with both the extraction and the sequencing of the microbes, so when we were able to find evidence of active microbial communities, it was a very satisfying experience."
The team isolated and sequenced DNA from the spring community, allowing them to reconstruct genomes from approximately 110 microorganisms, most of which have never been seen before. These genomes have allowed the team to determine how such creatures survive and thrive in this unique extreme environment, acted as blueprints for potential life forms in similar environments. Through mRNA sequencing, the team were able to identify active genes in the genomes and essentially identify some very unusual microbes actively metabolizing in the extreme spring environment.
No need for organic material to support life
"The microbes we found and described at Lost Hammer Spring are surprising, because, unlike other microorganisms, they don't depend on organic material or oxygen to live," adds Whyte. "Instead, they survive by eating and breathing simple inorganic compounds such as methane, sulfides, sulfate, carbon monoxide and carbon dioxide, all of which are found on Mars. They can also fix carbon dioxide and nitrogen gasses from the atmosphere, all of which makes them highly adapted to both surviving and thriving in very extreme environments on Earth and beyond."
The next steps in the research will be to culture and further characterize the most abundant and active members of this strange microbial ecosystem, to better understand why and how they are thriving in the very cold, salty, muck of the Lost Hammer Spring. The researchers hope that this, in turn, will help in the interpretation of the exciting but enigmatic sulfur and carbon isotopes that were very recently obtained from the NASA Curiosity Rover in the Gale Crater on MarsAstrophysicists investigate the possibility of life below the surface of Mars
More information:Elisse Magnuson et al, Active lithoautotrophic and methane-oxidizing microbial community in an anoxic, sub-zero, and hypersaline High Arctic spring,The ISME Journal(2022).DOI: 10.1038/s41396-022-01233-8
Here’s why pumpkin toadlets are such clumsy jumpers
Tiny inner ear canals may make it hard for the frogs to orient themselves in space Tiny Brachycephalus frogs from southern Brazil can leap into the air but have trouble landing. LUIZ F. RIBEIRO
After launching into a leap, pumpkin toadlets careen through the air as if flung from a toddler’s fist. They roll, cartwheel or backflip and then plummet to the ground, often belly flopping or crash-landing on their backs.
“I’ve looked at a lot of frogs and these are the weirdest things I’ve ever seen,” says Richard Essner, Jr., a vertebrate zoologist at Southern Illinois University Edwardsville.
Essner and colleagues now propose an explanation for why the tiny frogs are such clumsy jumpers. The animals lack the proper gyroscopic equipment to sense small changes in rotation, the team suggests June 15 in Science Advances. Brachycephalus pernix frogs have trouble sensing small changes in rotation, which makes landing jumps difficult, a new study suggests. The frogs can roll, cartwheel or backflip through the air, and then hit the ground on their backs or bellies.
When Essner saw videos of Brachycephalus frogs’ awkward aerial maneuvers, he was so shocked that he hopped on a plane to study the animals with his colleagues in Brazil. Small enough to fit on a person’s thumbnail, the frogs are tricky to find in the wild. Scientists listen for the amphibians’ high-pitched, buzzy calls and then scoop leaf litter into a bag, hoping to find a few toadlets.
In the lab, the team used high-speed video to record more than 100 tiny frog jumps. The klutzy tumbles suggested that the toadlets have trouble orienting themselves in space.
Typically, fluid sloshing through bony tubes in the inner ear help vertebrates sense their body’s position. CT scans revealed that the frogs’ tubes are the smallest ever recorded for adult vertebrates. Studies of other tiny animals suggest that the tubes don’t work so well in miniature. It’s difficult for the fluid to flow freely, Essner says. That means the frogs probably can’t sense how they’re twirling through the air, making it tough to prep for landing.
It’s possible that bony back plates offer some species crash protection, but the animals may stay grounded for safety (SN: 4/3/19). As Essner observed, the frogs are “almost always crawling really slowly.”
The spindly parts seem to be a magnet for birds and may break off easily, facilitating escape The sail swallowtail (Iphiclides podalirius) has tail-like projections on its
hind wings that may divert attacking birds away from the butterfly’s vital parts. CAROLINE GAUVIN/MOMENT/GETTY IMAGES PLUS
On some butterfly wings, “tails” may be more than just elegant adornments. They’re survival tools too, a study suggests.
The tails seem to attract the attention of attacking birds, keeping them away from a butterfly’s more vital body parts, researchers report May 25 in the Proceedings of the Royal Society B. The finding could help explain why wing tails have independently evolved multiple times across different moth and butterfly groups.
Evolutionary biologist Ariane Chotard of the National Museum of Natural History in Paris studies the wings of swallowtail butterflies, which make up the hundreds of species in the family Papilionidae. “A lot of these butterflies display tails,” Chotard says. “And we don’t really know why.”
Some butterfly species with false head or eyespot patterns on their wings are known to receive more attacks from predators in those regions. And Chotard and her colleagues wondered if tails were also a target.
So in the summer of 2020, the researchers collected 138 sail swallowtail butterflies (Iphiclides podalirius) from the wild in Ariege, France. Sail swallowtails — found throughout Eurasia — sport two, conspicuous black tails on hind wings with some blue and orange spotting, contrasting greatly with the rest of the insects’ yellow, striped coloration.
Among the collected swallowtails, 65, or 41 percent, had damaged wings, all of which had at least one tail damaged. When all 130 wings in this group of damaged butterflies were counted, more than 82 percent of the wings had damaged tails, suggesting that predators may be targeting the spindly parts
To test that idea, the team kept wild-caught songbirds called great tits (Parus major) in cages. The researchers then showed the birds dummy butterflies made from gluing real swallowtail wings to a fake body made of small pieces of black cardboard, and filmed the birds’ attacks on the faux insects.
Forty-three out of 59 beak strikes, or nearly 73 percent, were on the hind wings. Twenty-three, or 39 percent, of the strikes touched both a tail and colored areas on the upper part of a hind wing simultaneously, more than any other body area on the dummies. A captive great tit (Parus major) attacks the hind wings and “tails” of a dummy made with real wings from a sail swallowtail butterfly (Iphiclides podalirius). A new study suggests that the tails deflect attacks away from key body parts to brittle extensions that easily tear off, allowing the insect to flee.
Chotard and her colleagues also measured how much force was needed to tear various sections of the swallowtail wing. They found that the vein of the hind wing tail was the most fragile part of the wing and is probably the location most apt to break off in a hungry bird’s beak.
Taken together, the findings suggest that swallowtail tails deflect attacks away from the butterfly’s vulnerable body to brittle extensions that easily tear off, allowing the insect to escape, the researchers say. This may be similar to the strategy some lizards use when sacrificing their detachable tails to hungry predators.
It’s unclear if there are any costs to losing one or two tails, Chotard says. “You survived, you escaped from a predator, but maybe there’s a trade-off and maybe your flight will be [slower].”
Some moth tails can deflect the attacks of echolocating bats (SN: 2/16/15). “Now we have evidence that butterfly tails provide a similar benefit against visual predators,” says evolutionary biologist Juliette Rubin of the University of Florida in Gainesville who was not involved with the study.
Future work determining the survival benefits of the tails could be one next step, Rubin says. “It would be informative to see how live swallowtail butterflies — both with and without tails — fare against bird predators.”
Ancient ‘smellscapes’ are wafting out of artifacts and old texts
ID’ing odor molecules and brewing Cleopatra’s perfume are part of new research on past scents The spectrum of smells in ancient societies, and their possible cultural meanings, are being explored by scientists who study odor molecules, old documents and other archaeological finds. Here, a carved relief of an ancient Egyptian queen smelling a lotus flower represents the fragrant world that pharaohs and their families inhabited. ALAIN GUILLEUX/ALAMY STOCK PHOTO
Ramses VI faced a smelly challenge when he became Egypt’s king in 1145 B.C. The new pharaoh’s first job was to rid the land of the stench of fish and birds, denizens of the Nile Delta’s fetid swamps.
That, at any rate, was the instruction in a hymn written to Ramses VI upon his ascension to the throne. Some smells, it seems, were considered far worse than others in the land of the pharaohs.
Surviving written accounts indicate that, perhaps unsurprisingly, residents of ancient Egyptian cities encountered a wide array of nice and nasty odors. Depending on the neighborhood, citizens inhaled smells of sweat, disease, cooking meat, incense, trees and flowers. Egypt’s hot weather heightened demand for perfumed oils and ointments that cloaked bodies in pleasant smells.
“The written sources demonstrate that ancient Egyptians lived in a rich olfactory world,” says Egyptologist Dora Goldsmith of Freie Universität Berlin. A full grasp of ancient Egyptian culture requires a comprehensive examination of how pharaohs and their subjects made sense of their lives through smell, she contends. No such study has been conducted.
Archaeologists have traditionally studied visible objects. Investigations have reconstructed what ancient buildings looked like based on excavated remains and determined how people lived by analyzing their tools, personal ornaments and other tangible finds.
Rare projects have re-created what people may have heard thousands of years ago at sites such as Stonehenge (SN: 8/31/20). Piecing together, much less re-creating, the olfactory landscapes, or smellscapes, of long-ago places has attracted even less scholarly curiosity. Ancient cities in Egypt and elsewhere have been presented as “colorful and monumental, but odorless and sterile,” Goldsmith says.
Changes are in the air, though. Some archaeologists are sniffing out odor molecules from artifacts found at dig sites and held in museums. Others are poring over ancient texts for references to perfume recipes, and have even cooked up a scent much like one presumably favored by Cleopatra. In studying and reviving scents of the past, these researchers aim to understand how ancient people experienced, and interpreted, their worlds through smell.
Molecular odors
A growing array of biomolecular techniques is enabling the identification of molecules from ancient aromatic substances preserved in cooking pots and other containers, in debris from city garbage pits, in tartar caked on human teeth and even in mummified remains.
Take the humble incense burner, for instance. Finding an ancient incense burner indicates only that a substance of some kind was burned. Unraveling the molecular makeup of residue clinging to such a find “can determine what exactly was burned and reconstruct whether it was the scent of frankincense, myrrh, scented woods or blends of different aromatics,” says archaeologist Barbara Huber.
That sort of detective work is exactly what Huber, of the Max Planck Institute for the Science of Human History in Jena, Germany, and her colleagues did in research on the walled oasis settlement of Tayma in what’s now Saudi Arabia.
Researchers generally assume that Tayma was a pit stop on an ancient network of trade routes, known as the Incense Route, that carried frankincense and myrrh from southern Arabia to Mediterranean destinations around 2,300 to 1,900 years ago. Frankincense and myrrh are both spicy-smelling resins extracted from shrubs and trees that grow on the Arabian Peninsula and in northeastern Africa and India. But Tayma was more than just a refueling oasis for trade caravans.
The desert outpost’s residents purchased aromatic plants for their own uses during much of the settlement’s history, a team led by Huber found. Chemical and molecular analyses of charred resins identified frankincense in cube-shaped incense burners previously unearthed in Tayma’s residential quarter, myrrh in cone-shaped incense burners that had been placed in graves outside the town wall, and an aromatic substance from Mediterranean mastic trees in small goblets used as incense burners in a large public building.
Fragrances of various kinds that must have had special meanings permeated a range of daily activities at ancient Tayma, Huber’s group reported in 2018 in Munich at the 11th International Conference on the Archaeology of the Ancient Near East.
In a more recent study, published March 28 in Nature Human Behavior, Huber and her colleagues outlined ways to detect chemical and genetic traces of ancient scents.
Incense burners found at an Arabian Peninsula settlement called Tayma, represented by this cone-shaped artifact, contain clues to a range of fragrances used in daily activities roughly 2,000 years ago.A.D. RIDDLE/BIBLEPLACES.COM
Other researchers have gone searching for molecular scent clues in previously excavated pottery. Analytical chemist Jacopo La Nasa of the University of Pisa in Italy and his colleagues used a portable version of a mass spectrometer to study 46 vessels, jars, cups and lumps of organic material.
These artifacts were found more than a century ago in the underground tomb of Kha and his wife Merit, prominent nonroyals who lived during Egypt’s 18th dynasty from about 1450 B.C. to 1400 B.C. The spectrometer can detect the signature chemical makeup of invisible gases emitted during the decay of different fragrant plants and other substances that had been placed inside vessels.
Analyses of residue from inside seven open vessels and of one lump of unidentified organic material detected oil or fat, beeswax or both, the scientists report in the May Journal of Archaeological Science. One open vessel yielded possible chemical markers of dried fish and of a possible aromatic resin that could not be specified. The remaining containers were sealed and had to stay that way due to museum policy. Measurements taken in the necks of those vessels also picked up signs of oils or fats and beeswax in some cases. Evidence of a barley flour appeared in one vessel’s neck.
Museum-based studies such as La Nasa’s have great potential to unlock ancient scents. But that’s true only if researchers can open sealed vessels and, with a bit of luck, find enough surviving chemical components of whatever was inside to identify the substance, Goldsmith says.
Luck did not favor La Nasa’s group, she says. “Their analyses did not detect any [specific] scents.”
Oils, fats and beeswax in the seven open vessels could only have constituted neutral-smelling base ingredients for ancient Egyptian perfumes and ointments, Goldsmith says. Starting with mixtures of those substances, Egyptian perfume makers added a host of fragrant ingredients that included myrrh, resin and bark from styrax and pine trees, juniper berries, frankincense and nut grass. The heating of these concoctions produced strongly scented ointments.
Re-creating Cleopatra’s perfume
A tradition of fragrant remedies and perfumes began as the first Egyptian royal dynasties assumed power around 5,100 years ago, Goldsmith’s research suggests. Ancient Egyptian hieroglyphic and cursive documents describe recipes for several perfumes. But precise ingredients and preparation methods remain unknown.
That didn’t stop Goldsmith and historian of Greco-Roman philosophy and science Sean Coughlin of the Czech Academy of Sciences in Prague from trying to re-create a celebrated Egyptian fragrance known as the Mendesian perfume. Cleopatra, a perfume devotee during her reign as queen from 51 B.C. to 30 B.C., may have doused herself with this scented potion. The perfume took its name from the city where it was made, Mendes.
Excavations conducted since 2009 at Thmouis, a city founded as an extension of Mendes, have uncovered the roughly 2,300-year-old remains of what was probably a fragrance factory, including kilns and clay perfume containers (SN: 11/27/19). Archaeologist Robert Littman of the University of Hawaii at Manoa and anthropological archaeologist Jay Silverstein of the University of Tyumen in Russia, who direct the Thmouis dig, asked Goldsmith and Coughlin to try to crack the Mendesian perfume code by consulting ancient writings.
After experimenting with ingredients that included desert date oil, myrrh, cinnamon and pine resin, Goldsmith and Coughlin produced a scent that they suspect approximates what Cleopatra probably wore. It’s a strong but pleasant, long-lasting blend of spiciness and sweetness, they say.
Ingredients of a re-creation of an ancient fragrance called the Mendesian perfume consist of pine resin, cinnamon cassia, true cinnamon, myrrh and moringa oil (shown from left to right). Cleopatra herself may have worn the ancient scent.
D. GOLDSMITH AND S. COUGHLIN
A description of the Thmouis discoveries and efforts to revive the Mendesian scent — dubbed Eau de Cleopatra by the researchers — appeared in the Sept. 2021 Near Eastern Archaeology.
Goldsmith has re-created several more ancient Egyptian perfumes from written recipes for fragrances that were used in everyday life, for temple rituals and in the mummification process.
Ancient smellscapes
Odor molecules unearthed in archaeological digs and reconstituted perfumes from the past, however, offer only a partial view of the scents of thousands of years ago. To get a more complete picture of an ancient city’s or town’s range of smells — its smellscape — some archaeologists are combing ancient written texts for references to smell.
That’s what Goldsmith did to come up with what she thinks is a smellscape typical of ancient Egyptian cities. Here’s what a “smellwalk” through one of these cities would entail, she says.
In the royal palace, for instance, the perfumed smell of rulers and their family members would have overpowered that of court officials and servants. That would perhaps have denoted special ties to the gods among those in charge, Goldsmith wrote in a chapter of The Routledge Handbook of the Senses in the Ancient Near East, published in September of 2021
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Smells of aromatic substances ignited in incense burners (such as the one held here by the pharaoh Ramses II in a temple wall carving at the Karnak Temple Complex near Luxor, Egypt) held deep meaning for ancient Egyptians, researchers say.
PRISMA ARCHIVO/ALAMY STOCK PHOTO
In temples, priests anointed images of gods with what was called the 10 sacred oils. Though their ingredients are mostly unknown, each substance apparently had its own pleasing scent and ritual function. Temples mixed smells of perfumes, flowers and incense with roasted meat. Written sources describe the smell of fatty meat being grilled as especially pleasing and a sign of peace as well as authority over enemies.
In other parts of an ancient Egyptian city, Goldsmith says, scribal students lived in a special building where they learned Egyptian script. Achieving such knowledge required total devotion and the avoidance of perfume or other pleasant scents. One ancient source described aspiring scribes as “stinking bulls.” That name speaks, and reeks, for itself.
Meanwhile, in workshops, sandal-makers mixing tan to soften hides and smiths making metal weapons at the mouths of furnaces probably developed their own distinctive, foul smells, Goldsmith says.
Stinky odors get far fewer mentions than sweet aromas in many of the written accounts from ancient Egypt that Goldsmith reviewed. Goats and other domestic animals, butchered carcasses, open latrines and garbage in the streets, for example, get no mention in these surviving texts.
An awareness that such texts may represent only an elite perspective — and thus not reveal the entire smellscape of the time or how it was perceived by everyday folks — is crucial when compiling the scents of ancient history, Goldsmith says.
Cultured noses
Once researchers come up with a reasonable reconstruction of an ancient city’s smellscape, the challenge shifts to figuring out how the ancients interpreted those smells.
Scent is a powerful part of the human experience. Today, scientists know that smells, which humans might discriminate surprisingly well, can instantly trigger memories of past experiences (SN: 3/20/14). And social and ritual meanings also get attached to specific odors — there’s nothing like the smell of freshly mown grass and grilled hot dogs to evoke memories of summer days at the ballpark.
People in modern settings probably perceive the same smells as nice or nasty as folks in ancient Egypt or other past societies did, says psychologist Asifa Majid of the University of Oxford. In line with that possibility, members of nine non-Western cultures, including hunter-gatherers in Thailand and farming villagers in highland Ecuador, closely agreed with Western city dwellers when ranking the pleasantness of 10 odors, Majid and her colleagues report April 4 in Current Biology.
Smells of vanilla, citrus and floral sweetness — dispensed by pen-sized devices — got high marks. Odors of rancid oiliness and a fermented scent like that of ripe cheese or human sweat evoked frequent “yech” responses.
A collective “yech” in response to the Nile Delta’s moist, stinky emissions may have inspired the hymn that instructed Ramses VI to rid the land of its swampy fish and fowl smell. But Goldsmith argues that the hymn’s meaning is deeper and hinges on what ancient Egyptians saw as a conflict between sweet and evil smells.
In a 2019 review of texts written during the reigns of various ancient Egyptian kings, Goldsmith was struck by frequent references to this odiferous opposition. She concluded that ancient Egyptians’ largely unexplored views about what exemplified good and bad smells could provide insights into their world view. Researchers have long noted that concepts known as isfet and ma’at helped ancient Egyptians determine what was good or bad in the world. Isfet referred to a natural state of chaos and evil. Ma’at denoted a world of order and justice.
Signature odors were associated with isfet and ma’at, Goldsmith proposed in a chapter in Sounding Sensory Profiles in the Ancient Near East. In Nile societies, the smelly fish and birds best represented isfet’s nasal assault. Fish, in particular, signified not only stench but also the danger of unfamiliar places outside the pharaoh’s command, she concludes. Meanwhile, the ancient documents equated scented ointments and perfumes with the ma’at of civilized, pharaoh-ruled cities, she says.
Thus, an Egyptian pharaoh’s first duty was to erase the social and physical stink of isfet and institute the sweet smell of ma’at, Goldsmith contends. In his welcoming hymn, Ramses VI got a friendly reminder to make Egypt politically strong and olfactorily fresh.
Explicit beliefs connecting isfet with evil smells and ma’at with sweet smells throughout ancient Egyptian history haven’t yet been established but deserve closer scrutiny, says UCLA Egyptologist Robyn Price.
Price thinks that, rather than being fixed, values that were applied to scents fluctuated over time. For instance, some ancient texts describe the “marsh,” where fish and fowl flourished, as a place of divine creation, she says. And documents from southern Egypt often spoke negatively about northern Egyptians, perhaps influencing claims that northern marshes stunk of isfet during periods when the two regions were under separate rule.
So, even if the ancients tagged the same odors as pleasurable or offensive as people do today, culture and context probably profoundly shaped responses to those smells.
Working-class Romans living in Pompeii around 2,000 years ago — before Mount Vesuvius’ catastrophic eruption in A.D. 79 — provide one example. Archaeological evidence and written sources indicate that patrons of small taverns throughout the city were bombarded with strong smells, says archaeologist Erica Rowan of Royal Holloway, University of London. Diners standing or sitting in small rooms and at outdoor counters whiffed smoky, greasy food being cooked, body odors of other customers who had been toiling all day and pungent aromas wafting out of nearby latrines.
The smells and noises that filled Pompeii’s taverns provided a familiar and comforting experience for everyday Romans, who made these establishments successful, Rowan suspects. Excavations have uncovered 158 of these informal eating and drinking spots throughout Pompeii.
Pompeii residents eating at small taverns such as this one around 2,000 years ago may have whiffed a range of nice and nasty odors that the residents experienced as familiar and comforting.
AP PHOTO/GREGORIO BORGIA
Roman cities generally smelled of human waste, decaying animal carcasses, garbage, smoke, incense, cooked meat and boiled cabbage, Classical historian Neville Morley of the University of Exeter in England wrote in 2014 in a chapter of Smell and the Ancient Senses. That potent mix “must have been the smell of home to its inhabitants and perhaps even the smell of civilization,” he concluded.
Ramses VI undoubtedly regarded the perfumed world of his palace as the epitome of civilized life. But at the end of a long day, Egyptian sandal-makers and smiths, like Pompeii’s working stiffs, may well have smelled home as the air of city streets filled their nostrils.
N. Morley. Urban smells and Roman noses. In M. Bradley, ed., Smell and the Ancient Senses. New York, December 2014.
Lucy Cooke’s new book ‘Bitch’ busts myths about female animals
Sexism in biology has left females misunderstood
Female ring-tailed lemurs provide most territorial defense in their social groups, challenging stereotypes about male and female roles. RAIMUND LINKE/THE IMAGE BANK/GETTY IMAGES PLUS
To Charles Darwin, nature had a certain order. And in that order, males always came out on top. They were the leaders, the innovators, the wooers and the doers.
“The males of almost all animals have stronger passions than the females,” Darwin wrote in 1871. “The female, on the other hand, with the rarest of exceptions, is less eager.” The founder of evolutionary theory posited that throughout the animal kingdom, males are active, females are passive, and that’s pretty much that. Females, in sum, are boring.
That’s poppycock, Lucy Cooke writes in her latest book, Bitch. This blinkered view of nature as a man’s world was conceived and promulgated by Victorian men who imposed their values and world view on animals, she says. Cooke, a documentary filmmaker and the author of The Truth About Animals and two children’s books (SN: 4/14/18, p. 26), has traveled the world and met scientists who are exposing the truth about the sexes. She takes readers on a wild ride as she observes the ridiculous mating rituals of sage grouse, searches for orca poop (to monitor sex hormones) and watches female lemurs boss around males.
Through such adventures, Cooke learns that females are anything but boring. “Female animals are just as promiscuous, competitive, aggressive, dominant and dynamic as males,” she writes.
That may not sound radical to today’s feminists, but in the field of evolutionary biology, such a pronouncement has long bordered on the heretical. Generations of biologists have focused on male behavior and physiology, on the assumption that females are little more than baby-making machines to be won over by the strongest, showiest males.
Historically, when females did something potentially interesting, like exercise leadership over their social groups, many scientists scratched their heads and chalked it up as an aberration. When behavior didn’t fit the mold, like female-dominant spotted hyenas or peaceable male pinyon jays, it was either ignored or shoehorned into existing theory. For instance, ornithologists posited that aggressive female pinyon jays must suffer “the avian equivalent of PMS,” Cooke writes. The reality is that pinyon jays have a complex social hierarchy that doesn’t include the “alpha male” that scientists had expected. In recent years, scientists (many, but not all of them, female themselves) have begun to challenge Darwinian dogma about the sexes and submit it to rigorous testing.
Cooke draws on this recent science to systematically take down myths about females. She begins by asking what biological sex actually is — what makes a male a male, and a female a female — and shows that it’s far less black-and-white than we’ve been led to believe. Take the case of the European mole, in which the female sports gonads called ovotestes that produce eggs during the short breeding season, and testosterone the rest of the time. As a result, the female’s genitalia look just like the male’s, with a penislike clitoris and a vagina that vanishes after the breeding season.
The mole is just one example of sexual ambiguity among many that Cooke outlines. As the science of recent decades has revealed, even the genetics of sex is far more complicated than having either XX or XY chromosomes (which themselves are just one of many genetic systems for determining sex across the animal kingdom). In humans, males and females have the same set of about 60 sex-determining genes, which can create either testes or ovaries. Because of shared biology, the sexes are far more alike than they are different, and they exist in more of a continuum of bodies and behaviors than many people may be comfortable with.
Cooke also takes on many other ways scientists have misread sexual dynamics over the years, such as the myth that males benefit evolutionarily from promiscuity and females from monogamy. She addresses misconceptions about sexual cannibalism and animal genitals, complete with silicone replicas of animal vaginas. And she challenges ideas about the maternal instinct. As Cooke points out, males and females share the same neural circuitry, leading to fascinating experiments that stimulate certain nerve cells to flip male mice from infanticidal to doting dads.
In short, Cooke demolishes much of what you probably learned about the sexes in biology class. This may be disconcerting, even confronting for those who feel comfortable in the warm embrace of Darwinian order. But it’s also exciting, and fascinating, and very well might change the way you see the world.
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About Erika Engelhaupt Erika Engelhaupt is a freelance science writer and editor based in Knoxville, Tenn.
Ingredients of a re-creation of an ancient fragrance called the Mendesian perfume consist of pine resin, cinnamon cassia, true cinnamon, myrrh and moringa oil (shown from left to right). Cleopatra herself may have worn the ancient scent.
