What is the difference between a clade and a lineage?

What is the difference between a clade and a lineage?

A lineage is a single line of descent or linear chain within the tree, while a clade is a (usually branched) monophyletic group, containing a single ancestor and all its descendants.

What is the Phenetic species concept?

Informally, the phenetic species concept defines a species as a set of organisms that look similar to each other and distinct from other sets. More formally, it would specify some exact degree of phenetic similarity, and similarity would be measured by a phenetic distance statistic.

What is cohesion species concept?

Cohesion species concept. A cohesion species is “an evolutionary lineage that serves as the arena of action of basic micro evolutionary forces, such as gene flow (when applicable), genetic drift and natural selection” (Templeton, 1994).

What does least inclusive clade mean?

phylogenetic definitions as “the least inclusive clade comprising C and D” and its components “C” and “D” are not properties of anything, they just refer to an ontological individual ‘CD’ in the actual world. That is, they fix the reference of the name.

What do you call the place where two branches split apart?

The point where a split occurs, called a branch point, represents where a single lineage evolved into a distinct new one. A lineage that evolved early from the root and remains unbranched is called basal taxon. When two lineages stem from the same branch point, they are called sister taxa.

What do clades have in common?

A clade (from Ancient Greek κλάδος (kládos) ‘branch’), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree.

What is the major difference between monophyletic and non monophyletic groups?

A monophyletic group, sometimes called a clade, includes an ancestral taxon and all of its descendants. A monophyletic group can be separated from the root with a single cut, whereas a non-monophyletic group needs two or more cuts.

What is a sister group in phylogeny?

Two descendents that split from the same node are called sister groups. In the tree below, species A & B are sister groups — they are each other’s closest relatives. Many phylogenies also include an outgroup — a taxon outside the group of interest.