In his 1987 book, “The Evolution of Individuality,” Leo Buss addressed a fundamental biological question: “How could individual multicellular animals (known as metazoans), like sea anemones, insects, frogs, and humans arise?” Buss focused on a key challenge...
The placenta is the unique organ of therian mammals, key to their evolution and viability. The chorion is the outermost of the extra-embryonic membranes, and in birds and reptiles it is a simple membrane in contact with the shell allowing gas exchange. But in...
