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Viruses were expected to be small, but the range of sizes came as a surprise. Some were only a little smaller than the smallest known bacteria, and the smaller viruses were of similar sizes to complex organic molecules. [14] In 1935, Wendell Stanley examined the tobacco mosaic virus and found it was mostly made of protein. [15]
Until the Irish Great Famine of 1845–1852, the commonest cause of disease in potatoes was not the mould that causes blight, it was a virus. The disease, called "curl", is caused by potato leafroll virus, and it was widespread in England in the 1770s, where it destroyed 75 per cent of the potato crop. At that time, the Irish potato crop ...
1600–1650 South America malaria epidemic 1600–1650 South America Malaria: Unknown [citation needed] 1603 London plague (part of the second plague pandemic) 1603 London, England Bubonic plague: 40,000 [64] [65] [66] 1616 New England infections epidemic 1616–1620 Southern New England, British North America, especially the Wampanoag people
The history of biology traces the study of the living world from ancient to modern times. Although the concept of biology as a single coherent field arose in the 19th century, the biological sciences emerged from traditions of medicine and natural history reaching back to Ayurveda, ancient Egyptian medicine and the works of Aristotle, Theophrastus and Galen in the ancient Greco-Roman world.
Epidemics of the 19th century were faced without the medical advances that made 20th-century epidemics much rarer and less lethal. Micro-organisms (viruses and bacteria) had been discovered in the 18th century, but it was not until the late 19th century that the experiments of Lazzaro Spallanzani and Louis Pasteur disproved spontaneous generation conclusively, allowing germ theory and Robert ...
Paleovirology is the study of viruses that existed in the past but are now extinct. In general, viruses cannot leave behind physical fossils, [1] therefore indirect evidence is used to reconstruct the past. For example, viruses can cause evolution of their hosts, and the signatures of that evolution can be found and interpreted in the present ...
The findings, published in a series of articles in Current Archaeology, come from one of the largest ancient DNA projects in Europe involving 460 people who were buried in graves between 200AD and ...
[11]: 810 Once called "jumping genes", transposons are examples of mobile genetic elements and could be the origin of some viruses. They were discovered in maize by Barbara McClintock in 1950. [12] This is sometimes called the "vagrancy hypothesis", [8]: 16 [9]: 11–12 or the "escape hypothesis". [10]: 24 Co-evolution hypothesis