Taxonomy/Systematics Flashcards
what is etymology
the study or word origins
etymos =
true sense
logos =
word
what is taxonomy
the practive (and a little theory) of a classifying organisms
taxo =
arrange
nomos =
knowledge/ science of
what is systematics
the theory (and a little practice) of classifying organisms
what is nomenclature
system of rules for naming things
nomen =
name
what is ethnotaxonomy
examines how different cultures classify plants and animals
what is a common name
name for organisms that are not based on Linnaean system
what are some problems with common names
- common names can differ for a species
- same name for different species
- common name may imply incorrect relationships
who made the linnaean system
Carl Linnaeus
what book series did Carl Linnaeus write
Systema Naturae
What are the two proposals in Systema Naturae
- use of Latin as a universal language for nomenclature
- use of unique binomen (2 parts for each name)
What does a binomen have
genus name and a specific epithet
Within the Linnaean system, what are groups of organisms called?
Taxa
What are nested subsets within the Linnaean system?
taxonomic levels or ranks
All animals must be placed into the following taxonomic ranks:
Kingdom, Phylum, Class, Order, Family, Genus, Species
In 1990, what higher taxonomic rank was formed?
Domain - Archaea, Bacteria, Eukarya
what are the three formatting rules for scientific names
- genus and specific epithet always italicized
- Taxon name (expect epithet) capitalized when used as nouns
- A genus name may be abbreviated (Alces alces = A. alces)
when was the ICZN created
1905
what does the ICZN stand for
international code of zoological nomenclature
what do the ICZN rules determine
they determine how animal taxon anems should be formed and when they should be changed
when was the first day of the published binomial species names are considered official (first rule of ICZN)
january 1, 1758
why is the oldest published name of a taxon considered the correct one? (second rule of ICZN)
because it has priority, also called senior synonym. any recent ones are called junior synonyms
third rule of ICZN? hint: has to do with the author
the person who originally described that taxon is considered the taxons author
if the same name is used for two different taxa at the same rank, what happens?
the oldest names wins (senior homonym)
reminder: this is only for the SAME RANK
why can some plants or animals have the same genus name? (5th ICZN rule)
same names from different codes are not homonyms
can specific epithets share the same name as long as they arent in the same genus? (6th rule of ICZN)
Yes
7th rule of ICZN? hint: latin
names must be in Latin alphabet
What ending should there be for family names of animals? (7th rule of ICZN)
“-idae”
what should happen if a species is tranffered to a different genus? (9th rule of ICZN)
should be indicated by parentheses around the name of the author
eg. Hexacaudalges casuaricolus (Proctor)
what is a subspecies
morphologically different populations of a species are sometimes given names below the rank of species
what are those who engage in systematics called?
systematists
what do mdoern systematists focus on
they focus on the reasons why particular taza should be grouped together
how has the focus shifted in systematics
focus has switched from simply adding new taxa to methods for determining relatedness among taxa
what is molecular systematics
uses molecular genetics to stufy the evolution of relationships among individuals and species
what is statigraphy
temporal order in which fossils occur
what tools did systematists have to create sensible classfications?
-stratigraphy
-expertise in the taxon
-common sense about which aspects of things seemed more primitive vs advanced
in 1960 (or 1950??) , what new method arose to help systematists to create classifications in a more objective fashion?
Henningian systematics
who created the Hennigian systematics
German etomologist Willi Hennig
what is the Hennigian systematics based on?
based on ancestor-descendent relationships of species and higher taxa (shared evolutionary history)
clados
branch
phylon
tribe or race
gen
to create
what is a clade
a group or organisms whose close evolutionary relationship is suported by these characteristics
what are cladograms
branching diagrams showing hypothesized relationships
gramm
a mark or line
what do cladograms represent
they represent only the order of evolutionary events and which taxa share more recent common ancestors
do the lengths of branches in cladograms mean anything?
No
what is a node or branching point
its where lineages diverge
what is dichotomy
node tat splits into two taxa
dich
split in two
tom
cut
what is polytomy
unresolved pattern of divergence (usually splits into 3 or more)
what is a basal taxon
it branches off earliest in a cladogram
what are taxa
taxa are groups of organims that have been given scientific names by people
what is the goal of modern systematics
for taxa to represent clades of related organisms
what is an ingroup
systematists collect information of a group whose relationship tey are interested in untangling
what is a character
each type of sturcture behavior, etc
e.g. colour of iris
what is a state
manifestation of a character in a given taxon e.g. eye colour is orange in Columba livia
what are outgroups
characters for one or more taxathat are related to the ingroup but have divered from it at an earlier time
what is the goal of cladistic analysis
to construct a set of nested relationships that minimizes the number of times a character has to change states
what is parsimony
the simpliest explanation is most likely to be correct
what is priniciple of parsimony also known as?
Occam’s Razor
what is character-state polarization?
the ancestral state becomes derived (0–>1)
changes and relationships among taxa are often presented in a _______
cladogram
what is synapomorphy
a shared, derived character, common between an ancestor and its descendants (hair between mammals and vertebrates)
what is symplesiomorphy
refers to an ancestral character (trait-state) shared by two or more taxa (hair colour/texture of mammals)
syn=
together
apo=
away from
morph=
form
plesio=
near
autopomorphy
unique derived character state present in only one taxon (hair on a leopard)
auto=
self
what is homologous
character states that look the same have the same evolutionary origin
homo=
same
what does analogous/homoplasious/covergent mean
character states appear to be the same but they actually eveolved independently
what is a distance-based phylogram
the number of differences between taxa are represented by branch lengths
what is the main difference between distance-based phylograms and cladograms?
cladograms do not provide certain information with their branch lengths
