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Contaminated and Natural Lead Environments of Man
Authors:Clair C. Patterson PhD
Affiliation:1. Department of Geology and Geophysics , Massachusetts Institute of Technology , Cambridge , Mass;2. Division of Geological Sciences , California Institute of Technology , Pasadena , Calif , 91109
Abstract:Eight cases of conjoined twins have been observed to occur among more than 5,000 embryonating zebra fish eggs that had been submitted to elevated water temperature several hours after fertilization. A naturally occurring epidemic of conjoined twins in salmon roe is described, and the principles which may underly the formation of conjoined twins in selected vertebrates and mammals are discussed. It is thought that environmental rather than genetic causes are usually at work in their production.
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