Macroevolution and Phylogeny

What is macroevolution

evolutionary change above the species level, including the origin of new taxonomic groups, evolutionary trends, adaptive radiation, and mass extinctions

What is phylogeny

the evolutionary history and relationships among species or groups of organisms

What is a phylogenetic tree

a diagram that represents evolutionary relationships among organisms based on common ancestry

What is adaptive radiation

the rapid evolution of diversely adapted species from a common ancestor in response to new ecological opportunities

What are homologous traits

traits that are shared due to common ancestry, even if they serve different functions

What are analogous traits

traits that have similar function but evolved independently, often due to convergent evolution

What is convergent evolution

the independent evolution of similar traits in different lineages due to similar environmental pressures

What are the main causes of mass extinctions

catastrophic events such as asteroid impacts, volcanic eruptions, and climate change

What is punctuated equilibrium

a theory suggesting that species experience long periods of stability interrupted by brief periods of rapid evolutionary change

What is gradualism in evolution

the idea that evolution occurs slowly and continuously over long periods

Taxonomy

the ordered division and naming of organisms

Basal taxon

diverged early in the history of a group and originates near the common ancestor of the group

Sister taxa

groups that share an immediate common ancestor

Polytomy

a branch from which more than two groups emerge

Homoplasy

analogous structures or molecular sequences that evolved independently (bats and cats)

Shared ancestral character

a character that originated in an ancestor of the taxon

Shared derived character

an evolutionary novelty unique to a particular clade

Cladistics

classifies organisms by common descent

Clade

group of species that includes an ancestral species and all its descendants

Outgroup

a species or group of species that is closely related to the ingroup

Ingroup

the various species being studies

Maximum Parsimony

the tree that requires the fewest evolutionary events (appearances of shared derived characters) is the most likely