The light trifle of his substance -- Traveling across the face of time -- This race should end with them -- Attagirl -- An evening's revelry -- The sleeping branches -- Individual Z -- Mongrels -- Nine foot high complete -- Ed and Fred -- Ex ovo omnia -- Witches'-broom -- Chimeras -- You, my friend, are a wonderland -- Flowering monsters -- The teachable ape -- Yet did he greatly dare -- Orphaned at conception -- The planet's heirs

Presents a history of the human understanding of heredity and how it has shaped society, chronicling the transitions brought about by genetic research and making predictions about how evolving understandings are likely to impact the future