According to scientists from the University of Geneva, this organism can form multicellular ... like bacteria or yeast. Animals, however, evolved from single egg cells into multicellular organisms ...

Many species of multicellular organisms differ greatly from each other with respect to the types of developmental mechanisms and traits they have evolved. For instance, by definition every ...

The first life forms to appear on Earth were unicellular, i.e., composed of a single cell, such as yeast or bacteria. Later, ...