BIOL 1030 Chapter 26 Vocab

Biodiversity

The variety of life on Earth

Taxonomy

The naming and grouping of organisms

Systematics

The science of figuring out relationships between organisms

Phylogeny

The evolutionary history and relationship of a group of organisms

Taxon

Any named group (ex. Mammalia, Panthera, etc.)

Clade

A special group — an ancestor plus all its descendants

Binomial nomenclature

Two-part name, Genus + species epithet

Order of taxonomic hierarchies

Domain → Kingdom → Phylum → Class → Order → Family → Genus → species || Dear King Phillip Came Over For Great Soup

The 3 Domains of Life

Bacteria = diverse prokaryotes

Archaea = prokaryotes genetically distinct from Bacteria and more closely related to Eukarya

Eukarya = eukaryotes; protists, fungi, plants, animals

Anatomy of a Phylogenetic Tree

Root = Ancestral population from which all the other species originate

Node = Branching point representing the most recent common ancestor of descent lineages

Branch = Lineage

Morphology

Using fossils and anatomy to understand evolutionary relationships

Molecular Data

Using DNA, RNA, and proteins to understand evolutionary relationships

Biochemistry

Using metabolic pathways to understand evolutionary relationships

Homologies

Phenotypic and genetic similarities due to shared ancestry

Analogies

Similarities between organisms that are due to convergent evolution

Convergent Evolution

Similar environmental pressures / natural selection leading to evolution of similar structures in different evolutionary lineages

Monophyletic Group

Common ancestor + ALL descendants

True clades

Polyphyletic Group

Organisms from different lineages grouped together WITHOUT their most recent common ancestor

Paraphyletic

Common ancestor + SOME, but not all, descendants

Ancestral Character

A trait that was already present in an earlier ancestor (“older model“)

Derived Character

A trait that evolved later from the ancestral condition (“newer model“)

Shared Ancestral Trait

Ancestral trait shared by multiple taxa

Shared Derived Trait

Derived trait shared by multiple descendants of a common ancestor

Most useful for identifying clades

Plesiomorphy

An ancestral trait retained in a lineage

Apomorphy

A derived trait that evolved from the ancestral condition

Newly evolved character

Synapomorphy

Shared derived trait inherited from a common ancestor

Most important for tree-building

Autopomorphy

Derived trait unique to one lineage

Distinguishes the lineage but doesn’t group it with another organism

Homoplasy

Similar trait that evolved independently in different lineages

Convergent evolution

Outgroup

Closely related species or group that is outside the group being studied (ingroup)

Maximum Parsimony

Favors the tree that requires fewest evolutionary changes

Simplest explanation for observed character data

Why Phylogeny Matters

• Classification

• Conservation

• Research

• Prediction