mosaic evolution The evolution of different parts of an organism at different rates. For example, many aspects of the human phenotype have evolved relatively slowly or not at all since the hominids diverged from their primate ancestors, one notable exception being the nervous system, which has given humans their overwhelming selective advantage. Similarly, at a molecular level, some proteins evolve very rapidly, while others remain unchanged over millions of years. This high degree of evolutionary independence among different aspects of the phenotype permits flexibility; for example, when a population is faced with new selection pressures in a changing environment, only the most crucial components need to evolve, not the entire phenotype.

mosaic evolution Differential rates of development of various adaptive attributes that occur within the same evolutionary lineage. For example, a particular taxon might show greatly different rates of change with respect to the head, body, and limbs. This is a common phenomenon and makes the reconstruction of transitional fossil types very difficult.

mosaic evolution The differential rates of development of various adaptive attributes within the same evolutionary lineage. For example, a particular taxon might show greatly different rates of change with respect to the leaves, shoots, and roots. This is a common phenomenon and makes the reconstruction of transitional fossil types very difficult.

mosaic evolution Differential rates of development of various adaptive attributes within the same evolutionary lineage. For example, a particular taxon might show greatly different rates of change with respect to the head, body, and limbs. This is a common phenomenon and makes the reconstruction of transitional fossil types very difficult.

mosaic evolution The differential rates of development of various adaptive attributes that occur within the same evolutionary lineage. For example, a particular plant taxon might show greatly different rates of change with respect to the leaves, shoots, and roots and an animal taxon with respect to the head, body, and limbs. This is a common phenomenon and makes the reconstruction of transitional fossil types very difficult.