Pre-Lecture Quiz

2 million

Approximately ___ living species have been discovered and described so far on earth

Extant Species

Species which have survived to the present day instead of going extinct

eukaryotes

Most extant described species are…

Proximate Question

Questions dealing with mechanisms and do not always require evolutionary thinking

Ultimate Question

Questions concerned with evolutionary origins and functions

observation and induction

Hypothesis based science can occur after…

iterative (it circles back on itself)

The process of gaining knowledge in the sciences is…

Etymology

The study of word origins and the meaning of parts of words

Taxonomy

The practice of classifying organisms

Systematics

The theory of classifying organisms

Nomenclature

A system of rules for naming things

Etymos

“True sense,” Greek

Logos

“Word,” Greek

Taxo

“Arrange,” Greek

Nomos

“Knowledge,” Greek

Nomen

“Name,” Latin

Ethnotaxonomy

Examines how different cultures classify plants and animals

Common Name

The name for an organism that is not based on the Linnaean system and is in the language of the local people

having the same name for different species or the common name may imply incorrect relationships between species

Examples of problems arising from common names are…

Linnaean System

Created by botanist Carl Linnaeus, a system created for naming organisms with seven layers of classification

Domain, kingdom, phylum, class, order, family, genus, species (each of which are a taxon)

Did King Phillip come over for great soup?

Species Name Parts

Genus (italicised, capitalised) and specific epithet (italicised, lower case) which together make the species name

Domain

Highest taxon; recognises the most basic divisions of life, i.e. archaea, bacteria, and eukarya

Genus and specific epithet

____ are always italicised

specific epithet, capitalised

Taxon names (except __) are always ___ when used as nouns, but not when used as adjectives

genus, specific epithet

A ___ may be abbreviated but the ___ may not

ICZN

International Code of Zoological Nomenclature

animals

The ICZN only covers…

ICZN Rule 1

January 1, 1758 is the first day that published binomial species names are considered official

ICZN Rule 2

The oldest published name for a taxon is considered the correct one (i.e. it has priority) and is called the senior synonym

ICZN Rule 3

The person who originally described a taxon is considered the taxon’s author

ICZN Rule 4

If the same name is used for two different taxa at the same rank, the oldest name wins and is called the senior homonym

ICZN Rule 5

Same names from different codes are not homonyms

ICZN Rule 6

Specific epithets can be shared as long as they don’t share the same genus

ICZN Rule 8

Family names for animals end in ‘-idae’

ICZN Rule 7

Names must be in the Latin alphabet

ICZN Rule 9

If a species is transferred to a different genus this is indicated by parentheses around the name of the author

there is fear of a threat to stability of scientific knowledge

Application of the ICZN can be made if…

why particular taxa should be grouped together; instead of adding new taxa, determine relatedness amongst pre-existing taxa if possible

The focus of modern systematics is…

Stratigraphy

A branch of geology concerned with the study of strata and stratification (can determine the temporal order in which fossils occur)

Old-Style Evolutionary Systematics

Used stratigraphy, expertise in a specific taxon, and “common sense” about which morphologies seemed more primitive versus advanced to determine species names

Hennigian (Phylogenetic) Systematics

Created by Willi Hennig; naming that reflects ancestor-descendent relationships of species and higher taxa (i.e. shared evolutionary history)

focus on shared derived characteristics

Hennig argued that the best way to determine evolutionary relationships was to…

Clados

“Branch”

Phylon

“Tribe, race”

Gen

“To create”

Clade

A group of organisms with close evolutionary relationships

Gramm

“A mark or line”

the relative timing of evolutionary branching and which taxa shares more recent common ancestors

Cladograms represent only…

Node or Branching Point

Where lineages diverge in cladograms

Dichotomy

A fully resolved split into two taxa

as the first node after the root of the phylogenic tree

The hypothetical common ancestor on a cladogram appears…

Polytomy

An unresolved pattern of divergence

Dich

“Split in two”

Tom

“To cut”

Sister Taxa

Taxa stemming from the same node

Basal Taxon

Branches off the earliest in a cladogram into its own taxon

Ingroup

The group of living organisms whose relationships are being considered in a cladogram

character

Each structure, behaviour, etc. is termed a…

state

The manifestation of a character in a given taxon is termed its…

Sp.

Abbreviation for species, singular

Spp.

Abbreviation for species, plural

Outgroup

Denotes a taxon or lineage that is outside of a group of taxa being studied

construct a set of nested relationships that minimises the number of times a character has to change states

The goal of a cladistic analysis is to…

the fewest postulates (i.e. principle of parsimony)

The best hypothesis is the one requiring…

0, ancestral states

Outgroup states are set at ___ and are considered to be…

Character State Polarization

Labelling a state different from that in the outgroup as derived and coding it as 1

Synapomorphy

A character shared by multiple taxa also found in their most recent common ancestor

Syn

“Together”

Apo

“Away from”

Morph

“Form”

synapomorphy

The presence of vertebrae is a ____ of vertebrates

Symplesiomorphy

A character shared by multiple taxa also found in their earliest common ancestor

Plesio

“Near”

Autapomorphy

A unique derived character present only in one taxon

Auto

“Self”

synapomorphies

Only ____ are useful for reconstructing relationships in cladograms

have the same evolutionary origin (they are homologous)

Cladistics works the best when all character states that look the same…

Analogous or Homoplasious or Convergent Characteristics

Character states that look the same but evolved independently

matching of bases in selected gene sequences (as mutations can accumulate over evolutionary time and be unique to species)

Molecular approaches to reconstructing relationships usually focusses on…

Distance-Based Phylogram

Numbers of differences between taxa are represented by the length of the branches (unlike cladograms)

Time-Based Phylograms

Time since divergence between taxa are represented by the length of the branches (assuming a relatively constant rate of mutation accumulation)

Maximum Parsimony

A character of a phylogenic tree that maximises the total number of character state changes

monophyletic

True clades are…

Monophyletic

Clade contains a common ancestor for all of its descendants and no other unrelated taxa; the goal of a phylogenic tree is to have only these relationships

taxa are put together on the basis of superficial similarity (e.g. all organisms that have wings)

Polyphyletic groups are created when…

Paraphyletic

Groups formed that do not contain all the descendants of a common ancestor

taxa are removed that are highly divergent from the rest of the clade (e.g. they have many autopomorphies)

Paraphyletic groups are created when…

hypotheses

Phylogenic trees are…

Microevolution

Change in the genetic composition within a population or among populations within one species over time

Macroevolution

Evolutionary changes above the level of a single species (e.g. speciation events resulting in a new clade of organisms)

Nature Theology

The old study of the evidence of God in nature

Gradualistic processes in geology

____ influenced Darwin’s thoughts about evolution

Jean Baptiste Lamarck

Believed that apparent disappearances of species was actually one species slowly changing into another

Alfred Russel Wallace (1858)

Independently arrived at the same evolution through the process of natural selection as Charles Darwin

1859

“On the Origin of Species by Means of Natural Selection” was published in…

Darwin Observation 1

Organisms are capable of producing many more offspring than are needed to just replace themselves

Darwin Observation 2

Most populations are relatively stable in size because not all offspring survive

Darwin Observation 3

Resources are limited and there is not enough to support all offspring of all individuals

Thomas Malthus

Noted that human populations tend to increase faster than food production can, leading to war/famine/disease and ultimately declines in human populations