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Biologists’ Consensus on ‘When Life Begins’ by Steven Andrew Jacobs


Many Americans disagree on when life begins because they have different interpretations of the phrase:

     1.) descriptive (i.e., when a fetus is classified as a human)

     2.) normative (i.e., when a fetus is worthy of ethical and legal consideration).

To determine which is more prevalent, 2,899 American adults were surveyed and asked to select the group most qualified to determine when a human’s life begins. 81% selected biologists as the most qualified because they are scientists who objectively study life. This suggests Americans likely have a descriptive interpretation of ‘when life begins’. Biologists were then recruited to participate in a study. A sample of 5,502 biologists from 1,058 academic institutions assessed statements representing the biological view ‘a human’s life begins at fertilization’. A consensus affirmed each of the three statements representing that view (75-91%). Overall, 95% of biologists affirmed the view (5212 out of 5502). These findings suggest the descriptive view on when life begins centers on the biological classification of a fetus as a human at fertilization. These findings do not necessitate legal consideration of fetuses because it is not known if fetuses deserve rights or how those rights would be balanced against women’s reproductive rights. However, these findings can lead to such discussions. Biologists’ consensus on the descriptive view can help Americans move past the factual dispute on when life begins and focus on the normative issues in the abortion debate.