(Press-News.org) New research involving Cambridge University has found evidence — locked into an ancient stalagmite from a cave in the Himalayas — of a series of severe and lengthy droughts which may have upturned the Bronze Age Indus Civilization.
The beginning of this arid period — starting at around 4,200 years ago and lasting for over two centuries — coincides with the reorganization of the metropolis-building Indus Civilization, which spanned present-day Pakistan and India.
The research identified three protracted droughts — each lasting between 25 and 90 years — during this arid period. “We find clear evidence that this interval was not a short-term crisis but a progressive transformation of the environmental conditions in which Indus people lived,” said study co-author Prof Cameron Petrie, from Cambridge’s Department of Archaeology.
The researchers charted historic rainfall by examining growth layers in a stalagmite collected from a cave near Pithoragarh, India. By measuring a range of environmental tracers — including oxygen, carbon and calcium isotopes — they obtained a reconstruction showing relative rainfall at seasonal resolution. They also used high-precision Uranium-series dating to get a handle on the age and duration of the droughts.
“Multiple lines of evidence allow us to piece together the nature of these droughts from different angles — and confirm they are in agreement,” said lead author of the research Alena Giesche, who conducted the research as part of her PhD in Cambridge’s Department of Earth Sciences.
Giesche and the team identified distinct periods of below-average rainfall in both the summer and winter seasons. “The evidence for drought affecting both cropping seasons is extremely significant for understanding the impact of this period of climate change upon human populations,” said Petrie. He adds that the droughts during this period increased in duration, to the point where the third would have been multi-generational in length.
The findings support existing evidence that the decline of the Indus megacities was linked to climate change. “But what’s been a mystery until now is information on the drought duration and the season they happened in,” said Giesche. “That extra detail is really important when we consider cultural memory and how people make adaptations when faced with environmental change.”
According to Petrie: “The archaeological evidence indicates that over a 200 year period, the ancient inhabitants took various steps to adapt and remain sustainable in the face of this new normal.” During this transformation, larger urban sites were depopulated in favour of smaller rural settlements towards the eastern extent of the area occupied by Indus populations. At the same time, agriculture shifted towards reliance on summer-crops, especially drought-tolerant millets, and the population transitioned to a lifestyle that appears to have been more self-reliant.
Megadroughts have recently become a popular cause to explain a number of cultural transformations, including the Indus Valley, explains David Hodell, study co-author from Cambridge’s Department of Earth Sciences: “But the links are generally fuzzy because of difficulties involved in comparing climatic and archaeological records.” This is now changing because, “Palaeoclimate records are becoming progressively better at refining changes in rainfall on a seasonal and annual basis, which directly affects people's decision making,” said Hodell.
The team are now looking to expand their climate reconstructions to western parts of the Indus River Region, where the winter rainfall system becomes more dominant than the Indian Summer Monsoon, “What we really need are more records like this, from a west-east oriented transect across the region where the summer and winter monsoons interact — and, crucially, capturing the beginning of this arid period,” said Giesche.
“Currently, we have a huge blind spot on our maps extending across Afghanistan and Pakistan where the Indian summer monsoon and the Westerlies interact,” said Prof Sebastian Breitenbach, co-author and palaeoclimatologist at Northumbria University. “Sadly, the political situation is unlikely to allow for this kind of research in the near future."
“There’s more work to be done by both palaeoclimatologists and archaeologists,” said Hodell. “We are fortunate in Cambridge to have the two departments next door to one another.”
Tracking down how interacting rain zones influenced the Indus Civilisation has been one of the questions at the centre of the TwoRains Project, a collaboration between Cambridge and Banaras Hindu University, which was funded by the European Research Council (ERC).
END
For the rational design of new material compounds, it is important to understand the mechanisms underlying their synthesis. Analytical techniques such as nuclear magnetic resonance and spectroscopy are usually employed to study such mechanisms in molecular reactions. However, reaction pathways governing the formation of solid-state crystalline compounds remain poorly understood. This is partly due to the extreme temperatures and inhomogeneous reactions observed in solid-state compounds. Further, the presence of numerous atoms in solid crystalline compounds ...
Some things are related, others are not. Suppose you randomly select a person from a crowd who is significantly taller than the average. In that case, there is a good chance that they will also weigh more than the average. Statistically, one quantity also contains some information about the other.
Quantum physics allows for even stronger links between different quantities: different particles or parts of an extensive quantum system can "share" a certain amount of information. There are curious theoretical predictions about this: surprisingly, ...
Farming is one of the oldest activities in the world and has always been at the forefront of technological innovation. With mechanized equipment, modified seeds, and digital devices, every aspect of farming, from planting to harvesting is gradually getting optimized. These benefits have also translated to better crop yield estimation for crops such as soybean. Deep learning-based yield estimation models use approaches like regression, traditional bounding boxes, or density maps to make counting of seeds easier. Compared ...
Using hydrophones to eavesdrop on a reef off the coast of Goa, India, researchers have helped advance a new low-cost way to monitor changes in the world’s murky marine environments.
Reporting their results in the Journal of the Acoustical Society of America (JASA), the scientists recorded the duration and timing of mating and feeding sounds – songs, croaks, trumpets and drums – of 21 of the world’s noise-making ocean species.
With artificial intelligence and other pioneering techniques to discern ...
Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer. It’s also one of the deadliest. More than 90% of PDAC patients die within five years of diagnosis. Usually, by the time the cancer is identified, it has already spread.
“PDAC is often found too late for treatments like chemotherapy and surgery to be very effective,” Cold Spring Harbor Laboratory (CSHL) Professor Adrian Krainer says. “But if we can clearly understand the underlying genetic mechanisms of PDAC, this might lead to earlier diagnoses and new types of therapies.”
Krainer ...
Modern cameras and sensors, together with image processing algorithms and artificial intelligence (AI), are ushering in a new era of precision agriculture and plant breeding. In the near future, farmers and scientists will be able to quantify various plant traits by simply pointing special imaging devices at plants. However, some obstacles must be overcome before these visions become a reality. A major issue faced during image-sensing is the difficulty of combining data from the same plant gathered from multiple image sensors, also known as ‘multispectral’ or ‘multimodal’ ...
Metagenomic sequencing (mNGS) is a powerful diagnostic tool to detect causative pathogens in clinical microbiological testing. Rapid and accurate classification of metagenomic sequences is a critical procedure for pathogen identification in the dry-lab step of mNGS tests. However, this crucial step may be improved by classifying sequences within a clinically relevant timeframe.
To address this challenge, a BGI Genomics team led by Xuebin Wang has recently launched GPMeta, an ultra-fast pathogen detection approach, and published these highlights ...
In the United States suicide has become the second leading cause of premature death among those ages 10 to 24; it is the leading cause of death among teens ages 13 to 14.
Researchers from Florida Atlantic University’s Schmidt College of Medicine and collaborators conducted a study exploring trends in rates of suicide among 13 to 14 year olds in the U.S. from 1999 to 2018. They also explored possible modifications by sex, race, level of urbanization, census region, month of the year and day of the week.
Results, published online ahead of print in the journal Annals of Pediatrics and Child Health, showed that among children ages 13 to 14, suicide rates ...
Researchers from University of Notre Dame and The Ohio State University published a new Journal of Marketing study that examines how the use of unconventional spellings of a brand name impacts consumers’ inferences about and willingness to support the brand.
The study, forthcoming in the Journal of Marketing, is titled “‘Choozing’ the Best Spelling: Consumer Response to Unconventionally Spelled Brand Names” and is authored by John P. Costello, Jesse Walker, and Rebecca Walker Reczek.
Choosing a brand ...
Development of vaccines against SARS-CoV-2 has been rapid, but the rise of variants forces scientists to frequently modify treatments. Ideally, therapies would target mutation-resistant viral proteins, but this has proven difficult. Researchers reporting in ACS Central Science, however, have now developed a system that directly targets and degrades the viral RNA genome, reducing infection in mice. The method could be adapted to fight off many viruses, as well as treat various diseases.
Vaccines and antiviral drugs typically target proteins critical to viral infection and replication. This ...