The Neolithic |
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↑ Mesolithic |
↓ Chalcolithic |
The Neolithic decline was a rapid collapse in populations between about 3450 and 3000 BCE [1] [2] during the Neolithic period in western Eurasia. The specific causes of that broad population decline are still debated. [2] While heavily populated settlements were regularly created, abandoned, and resettled during the Neolithic, after around 5400 years ago, a great number of those settlements were permanently abandoned. [2] The population decline is associated with worsening agricultural conditions and a decrease in cereal production. [3] Other suggested causes include the emergence of communicable diseases spread from animals living in close quarters with humans. [2]
The population increase between 5950 and 5550 BP (4000 to 3600 BC) that preceded the decline was catalysed by the introduction of agriculture, [4] [3] along with the spread of technologies such as pottery, the wheel, and animal husbandry. [2] After the Neolithic decline, there were massive human migrations from the Pontic–Caspian steppe into eastern and central Europe, beginning approximately 4800 BP (2850 BC). [2]
An ancient version of the Yersinia pestis has come up from multiple skeletal studies throughout Eurasia, skeletons which have dated back to around the estimated periods of the Neolithic Decline. [2] [3] [5] [4] [6] Additionally, genomes of the plague have been found as far back as 5,000 BP in areas such as Latvia and Sweden.
A tomb in modern-day Frälsegården in Gökhem parish, Falbygden, Sweden, contained 79 corpses buried within a short time of one another about 4,900 years ago. [2] This discovery uncovered fragments of a unique strain of the plague pathogen Yersinia pestis found in two individual's teeth. [2] [3] [4] The strain contained the "plasminogen activator gene that is sufficient to cause pneumonic plague", an extremely deadly form of the plague which is airborne and directly communicable between humans. [4] This strain of plague, researchers claim, alongside high demands of resources whilst living in close proximity to each other, would have allowed a pneumonic plague to quickly spread amongst inhabitants and wipe them out. [2]
Neolithic-era human teeth from Eurasia have also shown evidence of some of the oldest strains of Yersinia pestis . [6] The ages of the skeletons identified between 2,800 and 5,000 years old, with seven of the one hundred and one individuals carrying similar sequences of the bacterium. [6] Additionally, studies of the ancient strains discovered show these ancient strains lack the Yersinia murine toxin (ymt), which would have prevented the strains from using fleas as a vector. [6]
A similar site was found in China in 2011; the site Hamin Mangha in northeast China dates back to approximately 5000 years ago and features a small structure filled with almost 100 bodies. [7] Whilst there are several theories as what the reasons are for so many bodies in one location, such as a geological disaster or a ritual sacrifice, a plague is also considered as a hypothesis. [7] In the case of the plague, despite being the weakest of the hypotheses, the placement of the bodies suggesting others carrying them in, alongside being intact before being burned, and the lack of artifacts alongside the bodies. [7] Two other sites like these have been found in Northeast China: Miaozigou and Laijia, [5] [7] but archaeologists did not speculate as to the causal agent. [8]
Some studies have contested the hypothesis that the plague was responsible for the Neolithic decline. Analysis of the plague bacteria that infected a hunter-gatherer in Latvia during this period indicates that, unlike modern plague strains, the strain which afflicted this man was incapable of causing flea-spread bubonic plague and could only cause septicemic plague via a rodent bite or a largely non-contagious case of pneumonic plague, implying that the disease would have had difficulty spreading across vast distances in a short amount of time. [9] The man identified in this particular case, after being studied, does not have a clear indicator of how much he was actually affected by the bacteria. [9]
Studies of the ancient variations of the bacteria have tried to show connections to the specific strain they studied and the more modern strands, such as ones during the Black Death. [2] [6] Studies in Sweden, on the Gok2 Neolithic Yersinia pestis strain, discovered it to be the basal to all known Y. pestis strains with the use of genome reconstruction, as well as containing plasminogen activators genes that would have allowed it to start a pneumonic plague. [2] Other cases revealed a lack of ability to be able to use fleas as a vector of transmission; the case in Sweden contained Yersinia murine toxin which prevented the use of fleas, alongside a separate case studying late bronze-age bodies revealing the use of fleas in transmission would have occurred around the time after the collapse, being a few hundred years off. [2] [6]
The Black Death was a bubonic plague pandemic that occurred in Europe from 1346 to 1353. It was one of the most fatal pandemics in human history; as many as 50 million people perished, perhaps 50% of Europe's 14th century population. The disease is caused by the bacterium Yersinia pestis and spread by fleas and through the air. One of the most significant events in European history, the Black Death had far-reaching population, economic, and cultural impacts. It was the beginning of the second plague pandemic. The plague created religious, social and economic upheavals, with profound effects on the course of European history.
Plague is an infectious disease caused by the bacterium Yersinia pestis. Symptoms include fever, weakness and headache. Usually this begins one to seven days after exposure. There are three forms of plague, each affecting a different part of the body and causing associated symptoms. Pneumonic plague infects the lungs, causing shortness of breath, coughing and chest pain; bubonic plague affects the lymph nodes, making them swell; and septicemic plague infects the blood and can cause tissues to turn black and die.
Yersinia pestis is a gram-negative, non-motile, coccobacillus bacterium without spores that is related to both Yersinia enterocolitica and Yersinia pseudotuberculosis, the pathogen from which Y. pestis evolved and responsible for the Far East scarlet-like fever. It is a facultative anaerobic organism that can infect humans via the Oriental rat flea. It causes the disease plague, which caused the Plague of Justinian and the Black Death, the deadliest pandemic in recorded history. Plague takes three main forms: pneumonic, septicemic, and bubonic. Yersinia pestis is a parasite of its host, the rat flea, which is also a parasite of rats, hence Y. pestis is a hyperparasite.
Septicemic plague is one of the three forms of plague, and is caused by Yersinia pestis, a gram-negative species of bacterium. Septicemic plague is a systemic disease involving infection of the blood and is most commonly spread by bites from infected fleas. Septicemic plague can cause disseminated intravascular coagulation and is always fatal when untreated. The other varieties of the plague are bubonic plague and pneumonic plague.
The plague of Justinian or Justinianic plague was an epidemic that afflicted the entire Mediterranean Basin, Europe, and the Near East, severely affecting the Sasanian Empire and the Byzantine Empire, especially Constantinople. The plague is named for the Byzantine Emperor Justinian I, who according to his court historian Procopius contracted the disease and recovered in 542, at the height of the epidemic which killed about a fifth of the population in the imperial capital. The contagion arrived in Roman Egypt in 541, spread around the Mediterranean Sea until 544, and persisted in Northern Europe and the Arabian Peninsula until 549. By 543, the plague had spread to every corner of the empire. As the first episode of the first plague pandemic, it had profound economic, social, and political effects across Europe and the Near East and cultural and religious impact on Eastern Roman society.
The Andronovo culture is a collection of similar local Late Bronze Age cultures that flourished c. 2000–1150 BC, spanning from the southern Urals to the upper Yenisei River in central Siberia and western Xinjiang in the east. In the south, the Andronovo sites reached Tajikistan and Uzbekistan. It is almost universally agreed among scholars that the Andronovo culture was Indo-Iranian. Some researchers have preferred to term it an archaeological complex or archaeological horizon.
Yersinia pseudotuberculosis is a Gram-negative bacterium that causes Far East scarlet-like fever in humans, who occasionally get infected zoonotically, most often through the food-borne route. Animals are also infected by Y. pseudotuberculosis. The bacterium is urease positive.
Bubonic plague is one of three types of plague caused by the bacterium Yersinia pestis. One to seven days after exposure to the bacteria, flu-like symptoms develop. These symptoms include fever, headaches, and vomiting, as well as swollen and painful lymph nodes occurring in the area closest to where the bacteria entered the skin. Acral necrosis, the dark discoloration of skin, is another symptom. Occasionally, swollen lymph nodes, known as "buboes", may break open.
The human flea – once also called the house flea – is a cosmopolitan flea species that has, in spite of the common name, a wide host spectrum. It is one of six species in the genus Pulex; the other five are all confined to the Nearctic and Neotropical realms. The species is thought to have originated in South America, where its original host may have been the guinea pig or peccary.
The Black Death was one of the most devastating pandemics in human history, resulting in the deaths of an estimated 75 to 200 million people in Eurasia, and peaking in Eurasia from 1321 to 1353. Its migration followed the sea and land trading routes of the medieval world. This migration has been studied for centuries as an example of how the spread of contagious diseases is impacted by human society and economics.
Theories of the Black Death are a variety of explanations that have been advanced to explain the nature and transmission of the Black Death (1347–51). A number of epidemiologists from the 1980s to the 2000s challenged the traditional view that the Black Death was caused by plague based on the type and spread of the disease. The confirmation in 2010 and 2011 that Yersinia pestis DNA was associated with a large number of plague sites has led researchers to conclude that "Finally, plague is plague."
The Black Death was a bubonic plague pandemic, which reached England in June 1348. It was the first and most severe manifestation of the second pandemic, caused by Yersinia pestis bacteria. The term Black Death was not used until the late 17th century.
The 1994 plague in India was an outbreak of bubonic and pneumonic plague in south-central and western India from 26 August to 18 October 1994. 693 suspected cases and 56 deaths were reported from the five affected Indian states as well as the Union Territory of Delhi. These cases were from Maharashtra, Gujarat, Karnataka, Uttar Pradesh, Madhya Pradesh and New Delhi. There are no reports of cases being exported to other countries.
Plasminogen activator Pla is an enzyme. This enzyme catalyses the following chemical reaction
The 1924 Los Angeles pneumonic plague outbreak was an outbreak of the pneumonic plague in Los Angeles, California that began on September 28, 1924, and was declared fully contained on November 13, 1924. It represented the first time that the plague had emerged in Southern California since plague outbreaks had previously surfaced in San Francisco and Oakland. The suspected reason for this outbreak was a rat epizootic where squirrels that were found to be plague infected were secondarily infected by rats. Due to the evidence of infected squirrels near San Luis Obispo County as late as July 1924 and the migration habits of both squirrels and rats, it is thought that squirrels were the original source of the plague outbreak in Los Angeles.
Madagascar has experienced several outbreaks of bubonic and pneumonic plague in the 21st century. In the outbreak beginning in 2014, 71 died; in 2017, 202 died. Smaller outbreaks occurred in January 2008, and December 2013.
Globally about 600 cases of plague are reported a year. In 2017 and November 2019 the countries with the most cases include the Democratic Republic of the Congo, Madagascar, and Peru.
Kirsten Bos is a Canadian physical anthropologist. She is Group Leader of Molecular Palaeopathology at the Max Planck Institute for Evolutionary Anthropology in Leipzig. Her research focuses on ancient DNA and infectious diseases.
Ancientpathogengenomics is a scientific field related to the study of pathogen genomes recovered from ancient human, plant or animal remains. Ancient pathogens are microorganisms, now extinct, that in the past centuries caused several epidemics and deaths worldwide. Their genome, referred to as ancient DNA (aDNA), is isolated from the burial's remains of victims of the pandemics caused by these pathogens.
In archaeogenetics, the term Western Steppe Herders (WSH), or Western Steppe Pastoralists, is the name given to a distinct ancestral component first identified in individuals from the Chalcolithic steppe around the turn of the 5th millennium BC, subsequently detected in several genetically similar or directly related ancient populations including the Khvalynsk, Repin, Sredny Stog, and Yamnaya cultures, and found in substantial levels in contemporary European, Central Asian, South Asian and West Asian populations. This ancestry is often referred to as Yamnaya ancestry, Yamnaya-related ancestry, Steppe ancestry or Steppe-related ancestry.