The 1:1 ratio results from the way the X and Y chromosomes are doled out in sperm and eggs. We know that boys and girls are produced in much the same frequency. But how – and why – is this 1:1 ...

Vivien Lesnik Weisman was born in Havana, Cuba. She graduated from Barnard College with a B.A. in Art History and Political Science and New York Law School with a Doctorate in Jurisprudence. She was ...