Mosaic evolution

Mosaic evolution is evolutionary change in which different traits within an organism or lineage evolve at different rates, producing combinations of ancestral and derived features.

Evolutionary modularity: The organization of biological systems into semi-independent units that can evolve with limited effects on one another. Semi-independent modules let one anatomical or behavioral trait change while others remain comparatively stable.
Evolution: Change in heritable characteristics of populations across generations. Mosaic evolution is a pattern within the broader process of evolutionary change.
Australopithecus afarensis: An extinct hominin species from East Africa, including the fossil skeleton known as Lucy. Its bipedal adaptations coexisted with a small brain, illustrating uneven change across traits.
Adaptive radiation: The diversification of a lineage into multiple species adapted to different ecological niches. It concerns diversification among lineages, rather than unequal change among traits within a lineage.
Developmental constraint: A limitation imposed by an organism’s development on the range or direction of possible evolutionary changes. Development can restrict change in some traits more than in others.
Phenotype: The observable characteristics of an organism, shaped by its genes and environment. Mosaic patterns concern differences in how particular phenotypic traits change.
Ardipithecus ramidus: An early hominin species from Ethiopia, known from fossils dating to about 4.4 million years ago. Its anatomy combines evidence of terrestrial bipedality with traits suited to climbing.
Convergent evolution: The independent evolution of similar traits in separate lineages. Similarity across lineages differs from the uneven trait histories within a lineage.
Natural selection: The differential survival and reproduction of organisms due to heritable variation in traits. Distinct environments and functions impose different selective pressures on separate traits.
Phylogenetic comparative methods: Statistical approaches that compare traits across species while accounting for shared evolutionary ancestry. These methods help distinguish independent trait histories from similarities inherited from common ancestors.

Linked from 14 pages