David Packouz is a Texan.
In phylogenetics , basal is the direction of the base -LRB- or root -RRB- of a rooted phylogenetic tree or cladogram .. phylogenetics. phylogenetics. rooted phylogenetic tree. phylogenetic tree#Rooted tree. cladogram. cladogram. Clade C may be described as basal within a larger clade D if its root is directly linked -LRB- adjacent -RRB- to the root of D .. Clade. Clade. If C is a basal clade within D that has the lowest taxonomic rank of all basal clades within D , C may be described as the basal taxon of that rank within D .. taxonomic rank. taxonomic rank. taxon. taxon. While there must always be two or more equally basal clades sprouting from the root of every cladogram , those clades may differ widely in rank or species diversity .. cladogram. cladogram. Greater diversification may be associated with more evolutionary innovation , but ancestral characters should not be imputed to the members of a less species-rich basal clade without additional evidence , as there can be no assurance such an assumption is valid .. diversification. Speciation. ancestral characters. Cladistics#Terminology for character states. In general , clade A is more basal than clade B if B is a subgroup of the sister group of A. Within large groups , `` basal '' may be used more loosely to mean ` closer to the root than the great majority of ' , and in this context terminology such as `` very basal '' may arise .. sister group. sister group. A ` core clade ' is a clade representing all but the basal clade of lowest rank within a larger clade .