A Greek text, attributed to Polybus, argues that the human body is composed of four humours

The Greek author Theophrastus writes On the History of Plants, the earliest surviving work on botany

German botanist Otto Brunfels publishes Living images of plants, the first serious work of natural history with printed illustrations

Tobacco is grown in Europe's physic gardens for its medicinal qualities

Swiss botanist Gaspard Bauhin begins work classifying 6000 plants on a new binomial system of nomenclature

Italian doctor Marcello Malpighi discovers the capillaries, thus completing the evidence for the circulation of the blood

The Dutch scientist Anton van Leeuwenhoek builds a microscope powerful enough for him to observe and describe the red corpuscles in blood

With his powerful new microscope Leeuwenhoek observes spermatozoa in the semen of a dog

English naturalist John Ray begins publication of his Historia Plantarum, classifying some 18,600 plants in 'mutual fertility' species

Swedish naturalist Carolus Linnaeus publishes a 'system of nature', capable of classifying all living things

Captain Cook's distinguished passengers, Joseph Banks and Daniel Solander, collect valuable specimens of Pacific flora

James Hutton describes to the Royal Society of Edinburgh his studies of local rocks , launching the era of scientific geology

English surveyor William Smith compiles a manuscript, Order of the Strata, revealing chronology through fossils in rocks

French biologist Jean-Baptiste Lamarck argues in Zoological Philosophy that creatures can inherit acquired characteristics

A 12-year-old Dorset child, Mary Anning, discovers at Lyme Regis a 21 ft (6.4m) fossil of an icthyosaur

French scientist Georges Cuvier introduces scientific palaeontology with his Research on the Fossil Bones of Quadrupeds

HMS Beagle sails from Plymouth to survey the coasts of the southern hemisphere, with Charles Darwin as the expedition's naturalist

French zoologist Félix Dujardin identifies protoplasm, the viscous translucent substance common to all forms of life

HMS Beagle reaches Falmouth, in Cornwall, after a voyage of five years, and Charles Darwin brings with him a valuable collection of specimens

Louis Agassiz builds a hut on the Aar glacier in Switzerland and succeeds in recording gradual movement of the ice

Swiss scientist Louis Agassiz argues, in his Study on Glaciers, that much of Europe was recently in the grip of an ice age

Swiss naturalist Louis Agassiz completes his pioneering Poissons Fossiles ('Fossil Fish'), classifying more than 1500 categories

An American clergyman, L.L. Langstroth, discovers the 'bee space', which becomes a standard feature of the modern beehive

Austrian monk Gregor Mendel begins his study of pea plants in the garden of the Abbey of St Thomas in Brno

English physician John Snow proves that cholera is spread by infected water (from a pump in London's Broad Street)