Free Republic

A new technique for finding and characterizing microbes has boosted the number of known bacteria by almost 50 percent, revealing a hidden world all around us.It used to be that to find new forms of life, all you had to do was take a walk in the woods. Now it’s not so simple. The most conspicuous organisms have long since been cataloged and fixed on the tree of life, and the ones that remain undiscovered don’t give themselves up easily. You could spend all day by the same watering hole with the best scientific instruments and come up with...

The recent surge in interest in the origins of multicellular animals (metazoans) is fueled by new evidence from three major sources: molecular sequencing, the study of evolutionary development and the discovery of exceptionally preserved fossils of Precambrian and Cambrian age, particularly from China. Genetic sequences provide a means of analyzing how the major animal groups are related and of estimating their time of origin (using the molecular clock) — a means that is independent of morphological data and the record of evolutionary events the fossils reveal. The study of developmental processes in an evolutionary framework ("evo-devo") provides the link between...