Ethical commitments in anthropology include noticing and documenting genocide, infanticide, racism, mutilation (including circumcision and subincision), and torture. Topics like racism, slavery, and human sacrifice attract anthropological attention and theories ranging from nutritional deficiencies to genes to acculturation have been proposed, not to mention theories of colonialism and many others as root causes of Man's inhumanity to man. To illustrate the depth of an anthropological approach, one can take just one of these topics, such as "racism" and find thousands of anthropological references, stretching across all the major and minor sub-fields.