Next lecture: the human microbiome, health and disease. Friday"s lecture: the other members of the microbiome. This represents a pubmed search for human microbiome, human microbiota, human flora, human microflora. Whether you"re working in cancer or the environment etc, there will be some relevance with respect to the human microbiome. 1683: comparison of bacteria from teeth of several individuals van leeuwenhoek: called them animalcules. 1865: louis pasteur shows that microbes cause disease in french silkworms: organisms that we cannot see cause disease. Germ theory: anthrax, leprosy, gonorrhoea, typhoid, tuberculosis, cholera, diphtheria, tetanus, plague. Development of antiseptic techniques, sanitation improvement, food preservation methods. 1888: martinus beijerinck discovers that bacteria transform nitrogen into ammonia making it readily available for plants. 1909: arthur kendall describes bacteria in the healthy human gut and suggest their importance for human health: he didn"t go very far into this explanation.