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human evolution

(Encyclopedia)human evolution, theory of the origins of the human species, Homo sapiens. Modern understanding of human origins is derived largely from the findings of paleontology, anthropology, and genetics, and i...

human papillomavirus

(Encyclopedia)human papillomavirus (HPV), any of a family of more than 100 viruses that cause various growths, including plantar warts and genital warts, a sexually transmitted disease. Genital warts, sometimes cal...

human rights

(Encyclopedia)human rights, universal rights held to belong to individuals by virtue of their being human, encompassing civil, political, economic, social, and cultural rights and freedoms, and based on the notion ...

Hartline, Haldan Keffer

(Encyclopedia)Hartline, Haldan Keffer, 1903–83, American physiologist, b. Bloomsburg, Pa., M.D. Johns Hopkins, 1927. From 1931 to 1949 (except for 1940–41), he was a researcher at the Eldridge Reeves Johnson Fo...

nearsightedness

(Encyclopedia)nearsightedness or myopia, defect of vision in which far objects appear blurred but near objects are seen clearly. Because the eyeball is too long or the refractive power of the eye's lens is too stro...

guide dog

(Encyclopedia)guide dog, a dog trained to lead a blind person. The first school for training such dogs was established by the German government after World War I for the benefit of blinded veterans. Schools now exi...

blindness

(Encyclopedia)blindness, partial or complete loss of sight. Blindness may be caused by injury, by lesions of the brain or optic nerve, by disease of the cornea or retina, by pathological changes originating in syst...

neurology

(Encyclopedia)neurology no͝orŏlˈəjē, nyo͝o– [key], study of the morphology, physiology, and pathology of the human nervous system. As researchers, neurologists carry on investigative and experimental work i...

stereoscope

(Encyclopedia)stereoscope stĕrˈēəskōpˌ [key], optical instrument that presents to a viewer two slightly differing pictures, one to each eye, to give the effect of depth. In normal vision the two eyes, being a...

Zaleucus

(Encyclopedia)Zaleucus zəlo͞oˈkəs [key], fl. c.650 b.c., Greek lawgiver of Locris, in Italy. According to tradition, his was the earliest codification of Greek law. References to Zaleucus' code, which was widel...