12/5/23 bio lecture Flashcards
Taxonomy
science of naming/describing/classifying living & extinct organisms (and viruses)
* Hierarchical (domain through species
Phylogeny
evolutionary relationships/history of a group or species
Systematics
(involves taxonomy + phylogeny)
study of biological diversity & evolutionary relationships
Taxonomic groups are based on
hypotheses regarding evolutionary relationships derived from systematics
phylogenetic trees show the relationships;
taxon
a taxonomic group (domain, phylum, genus, or supergroup)
Domain
All of life belongs to one of 3 domains Bacteria, Archaea, and Eukarya
Binomial nomenclature
standard format for naming organisms (scientific names)
Genus name always
Capitalized
Both genome and species are always
italicized
Understanding monophyletic, paraphyletic, and polyphyletic groupings
remember: organisms are grouped based on morphological, physiological, and molecular data and characteristics; trees are hypotheses that showthese relationships.
paraphyly
common ancestor, but not all descendants.
polyphyly
includes organisms with mixed evolutionary origin but does’nt include most recent common ancestor.
Monophyletic group
Taxon that is a clade
Includes an ancestral organism and all of its descendants;
Systematics is based on
morphological and/or genetic homology
Cladistics
study and classification of species based on evolutionary relationships
cladograms
phylogenetic trees by considering the possible pathways of evolutionary change
symplesiomorphy
Shared primitive character
synapomorphy
Shared derived character
Branch point
where two species differ in a character
ingroup
group we are interested in
outgroup
species or group of species that is assumed to have diverged before the species in the ingroup
An outgroup will lack
ne or more shared derived characters that are found in the ingroup
Molecular systematics
Analysis of genetic data, such as DNA and amino acid sequences, to identify and study genetic homologies and propose phylogenetic trees
When building cladograms,
choose the option that provides the simplest explanation of the data.