Lecture 2: Classification And Phylogenetics

Front 1

What's the definition of systematics?

Back 1

the study of biological diversity and its evolution.

Front 2

Taxonomy

Back 2

the process of biological classification (= categorizing and naming biological diversity)

Front 3

Phylogenetics

Back 3

the science of phylogeny (the evolutionary history of a group of species).

Front 4

What's Linnaean Classification?

Back 4

a hieracrchical method of naming: King Phillip Came Over For Genus Species:
Kingdom, Phylum, Class, Order, Family, Genus, Species

Front 5

T or F, the linnaen method was fundamentally flawed. Explain (give an example).

Back 5

T. ex: if birds descended from reptiles, at what point did they stop belonging to Reptillia and start belonging to Aves? What group do you put the Archaeopteryx which is bird-like and reptile like?

Front 6

What does the Linnaean classification work well for though?

Back 6

summarizing evolutionary diversity

Front 7

What is the most fundamental unit of biological classification?

Back 7

species (all higher categories are at least somewhat arbitrary).

Front 8

What do higher categories depend on?

Back 8

1) quality of evolutionary trees (phylogeny)
2)decisions about where to draw the breakpoints
(even in the best studied groups (birds and mammals), we are still discovering many unknown species).

Front 9

How are species named?

Back 9

with a latin binomial that includes the genus name and the species name
ex: Canus familiaris, Homo sapiens (Genus, species)

Front 10

What is someties listed following the species name?

Back 10

the name of the person who first described the species

Front 11

Who gets to name a species??

Back 11

whomever describes the new species first.

Front 12

What are 2 naming conventions everyone should know?

Back 12

1) genus and species names are italicized.
2) sometimes genus is abbreviated:
D. melanogaster

Front 13

what's the plural of genus?

Back 13

genera

Front 14

what does "spp." mean?

Back 14

used when referring to multiple species within a genus:
Drosophila spp.

Front 15

What does the third word in a trinomial name give?

Back 15

the subspecies (geographic race)

Front 16

T or F. Lots of species have been identified.

Back 16

F. Only a small fraction of species have been identified (maybe 10%)

Front 17

_______ is the cornerstone of all ecology and evolutionary biology. Explain.

Back 17

Species identification. Ecosystem functioning can no be well understood if species are not characterized. Identification and mitigation of human damage to biodiversity requires species IDs

Front 18

Species ID is often ___________ important. Explain

Back 18

economically. Ex: economic importance of taxonomy: phytophthora (plant killer) BAD economic impact

Front 19

T or F. The same tree can be drawn in different ways.

Back 19

T

Front 20

What are nodes?

Back 20

Points where 1 (ancestral) lineage splits into 2 or more (derived) lineages

Front 21

What do branches or internodes show?

Back 21

ancestral populations through time

Front 22

What do termini or tips show?

Back 22

most recent (derived) branches (can be living or extinct

Front 23

what's a taxon?

Back 23

any named group of organisms.

Front 24

What's an operational taxonomic unit (OTU)?

Back 24

one of the organisms being compared in a phylogenetic analysis.

Front 25

What is polytomy?

Back 25

a node with more than 2 derived lineages

Front 26

Define clade (monophyletic group).

Back 26

the set of species descended from a particular common ancestor.

Front 27

What are some characters used to reconstruct phylogenetic relationships?

Back 27

1) morphological traits (color, structures, etc.)
2)Biochemical traits (DNA, proteins, etc.)
3) Behavioral traits, etc.

Front 28

Define homology

Back 28

similarity that results from inheritenceof traits from a common ancestor

Front 29

Define homoplasty

Back 29

similarity in characters found in different species that is due to convergent evolution, parallelism, or reversal but NOT COMMON DESCENT.

Front 30

Define convergent evolution

Back 30

character similarity resulting rom independent responses to a similar environment. Example: wings of bats and birds, eye structure of octopus and fish, and placement of eyes in hippos and crocks.

Front 31

what's parallel evolution?

Back 31

character similarity in closely related taxa resulting from independent responses to a similar environment.