Ch. 17 Classification of Organisms Bio
The Linnaean System
Domain Kingdom Phylum/Division Class Order Family Genus Species ***THINK: Dumb Kings Play Chess On Fat Girls' Stomach***
John Ray
English naturalist who wrote Historia Plantarum; organized thousands of plants based on visual similarities and differences
Species names generally come from...
Latin roots, which are intended to be the same for all countries and in every language
How does the classification process used by modern taxonomists differ from that used by Linnaeus?
MT consider evolutionary history of an organism when classifying the organism; L considered mainly the organism's morphology
The oldest known fossils of cells appear to be _______
bacterial cells
domain
categories above the kingdom level
Early naturalists found that common names, such as robin or fir tree, weren't useful to identify organisms because...
common names vary from place to place and many don't accurately define a species.
Archaea
consists of prokaryotes; have distinctive cell membranes and other unique biochemical and genetic properties; some are autotrophic and are able to produce food by chemosynthesis; some produce flammable gas as waste products; many inhabit harsh environments; ex:
Conrad Gessner
Swiss naturalist who published Historia Animalium, categorizing thousands of animals into quadrupeds, birds, fish, and snakes
analogous features
features that have a similar function rather than similar lineage
Linnaeus gave an organism a species name, or scientific name, with 2 parts: the _______ followed by the _______.
genus name; species identifier
clade
group of organisms that includes an ancestor plus all of its descendants
Carl Woese
microbiologist of the University of Illinois who proposed a major revision of the system that had classified Earth's diversity into 6 kingdoms; compared rRNA sequences from many different organisms and then grouping these organisms according to their similarities
Use phylum when talking about...
non-plants
Linneaus grouped organisms according to similarities that he could...
readily see
Theophrastus
student of Aristotle who lived from 370 bce to 285 bce and recorded 500 plant types, classified into herbs, shrubs, "pre-shrubs", and trees
phyla/division
subsets below the kingdom level
phylogenetics
the analysis of the evolutionary or ancestral relationships among taxa
phylogeny
the evolutionary history of a species or taxon
systematics
the goal is to classify organisms in terms of their natural relationships
The molecular clock hypothesis suggests that...
the grater the differences between a pair of sequences, the longer ago those two sequences diverged from a common ancestor
kingdom
the largest category for Linnaeus; 2nd largest in modern day's version
Eukarya
the most familiar group of organisms; consists of eukaryotic organisms; have cells that are large and have a true nucleus and complex organelles; includes plants, animals, fungi, and a variety of single-celled organisms
If 2 species have the same banding pattern in regions of similar chromosomes...
the regions are likely to have been inherited from a single chromosome in the last common ancestor of the 2 species
taxonomy
the science of describing, naming, and classifying organisms
species
the smallest grouping, which contains only a single kind of organism
binomial nomenclature
the system of 2-part names
Advances in ________, ________, and _______ in the Middle Ages greatly expanded people's lists of observed organisms.
transportation, navigation, and exploration
subspecies
variations of a species that live in different geographic areas
The definition for Protista is troubling because it defines organisms based on...
what they aren't rather than what they are
protists
members of the kingdom Protista
3 of the most important insights about the relationships between major groups
1. all organisms are related by one ancient organism 2. Living things are related by ancestry to 1 of 3 domains 3. Archaea was separated from Bacteria, due to major differences
the 3 types of evidence systematics use to hypothesize about phylogenetics
1. they compare the visible similarities among currently living species or fossils from extinct organisms 2. comparing patterns of embryonic development and the ways in which the embryos of different species express similar genes 3. comparing similar chromosomes and macromolecules
The three domains
Archaea, Bacteria, and Eukarya
Cladist taxonomists have grouped crocodiles and birds together in a clade named _______
Archosauria
_______ classified organisms into only 2 taxa.
Aristotle
Explain how Earth's biodiversity relates to classification.
Biological classification is a way of organizing the variety of organism on Earth into meaningful groups
How were the classification systems of Aristotle and Linnaeus similar and different?
Both divided all living things into 2 main groups, plants and animals, but Aristotle's system had 3 sublevels each for animals and plants, whereas Linnaeus' system had 6 sublevels. Aristotle also divided animals on the basis of habitat and plants on the basis of stem differences, whereas Linneaus divided all organisms on the basis of morphology. Aristotle used common names, whereas Linnaeus used binomial nomenclature
Willi Hennig
German biologist that developed cladistics
Aristotle
Greek philosopher who observed and recorded nature in a scholarly way
What criteria did Linnaeus use to classify organisms?
He used an organism's form and structure as the basis for classification
The species name for humans is
Homo sapiens
molecular clock
a tool for estimating the sequence of past evolutionary events
How do researchers catalog insect species?
Researchers may fog the treetops with insecticide and then catch the falling insects in a net. They then will count and classify the insects.
C. J. Temminck
a 19th-century Dutch naturalist who first collected a specimen of the pangolin' species; the identifier for the pangolin's species, temminckii, commemortes him
Carlous Linnaeus
a Swedish naturalist who devised a system of grouping organisms into hierarchical categories according to their form and structure----morphology
biodiversity
a branch of biology that considers a variety of organisms at all levels from populations to ecosystems
Cladists assume that organisms that share one or more derived characters probably inherited those characters from _______
a common ancestor
shared character
a feature that all members of a group have in common
derived character
a feature that evolved only within the group under consideration
Chromosomes can be stained to reveal...
a pattern of bands
genus
a smaller grouping, under family
family
a smaller grouping, under order
What is the pangolin?
a species that is covered with scales and catches ants with its sticky tongue
cladistics
a system of phylogenetic analysis that uses shared and derived characters as the only criteria for grouping taxa
A subspecies name goes where in the scientific name?
after the species identifier
Archaebacteria
aligns with the domain Archaea; "ancient bacteria"
a fluid filled sac called a(n) _______ surrounds the embryos of reptiles, birds, and mammals
amnion
last universal common ancestor
an ancient organism or form of life from which all organisms inherited their rRNA genes
Terry Erwin
an ecologist who has been working to catalog insect species in plots of tropical rain forest
out-group
an organism that is only distantly related to the other organisms; a starting point for comparisons with the other organisms being evaluated
phylogenetic tree
another name for a phylogenetic diagram
taxon
any particular group within a taxonomic system
Archaea are so different from bacteria that many biologists now prefer to use only the name _______ for Archaebacteria
archaea
Aristotle grouped plants based on what?
differences in stem
orders
each class contains these
classes
each phylum consists of these
Modern biologists consider not only visible similarities but also similarities in...
embryos, chromosomes, proteins, and DNA
the theory of endosymbiosis
eukaryotic cells arose when ancient prokaryotic cells began to live together as one cell
The fossil record may lack...
evidence about many kinds of organisms, especially small and soft-bodied organisms
Phylogenetic diagrams may change whenever new discoveries and investigators cause scientists to revise their _______
hypothesis
The species name is written how?
in italics/underlined with the genus name capitlaized
homologous features
items that share a common ancestry
Fungi
kingdom of eukaryotes; consists of eukaryotic, heterotrophic organisms that are unicellular or multicellular, and that gain nutrients in a unique way; absorb rather than ingest nutrients
Plantae
kingdom of eukaryotes; consists of eukaryotic, multicelluar plants; except for a few parasitic species, most are autotrophic, use photosynthesis as a source of energy, and develop from embryos; most live on land
Animalia
kingdom of eukaryotes; eukaryotic, multicellular, and hetertrophic organisms that develop from embryos; most have symmetrical body organization and move around their environment to find and capture food
Eubacteria
kingdom that aligns with the domain bacteria; "true bacteria"
Aristotle grouped animals according to whether they lived on _______, in _______, or in _______.
land; water; air
phylogenetic diagram
looks like a family tree and has a branching pattern that indicates how closely related a subset of taxa are thought to be
Bacteria
made up of small, single-celled prokaryotic organism that reproduce by cellular fission; each has a cell wall, plasma membrane, a cytoplasm that lacks complex organelles, and at least one circular chromosome; don't have membrane-bound DNA and thus lacks a true nucleus; ex:
domains
major lineages
On a molecular cladogram, branch lengths are proportional to the...
number of amino acid changes
Protista
one of the 4 kingdoms of eukaryotes; those eukaryotes that are not plants, animals, or fungi
amniotes
organisms having an amnion
prokaryotes
organisms whose cells are smaller than eukaryotic cells and have neither a nucleus nor membrane-enclosed organelles
eukaryotes
organisms whose cells posses a membrane-enclosed nucleus and many other cell organelles
Why don't biologists classify the pangolin with other mammals that use sticky tongues to eat ants?
pangolins share more similarities with dogs and cats than with the other ant-eating mammal species
Why don't biologists classify the pangolin with other scaly animals, such as lizards and crocodiles?
pangolins share more similarities with mammals such as dogs and cats than with lizards or crocodiles
cladograms
phylogenetic diagrams cladists create
Systematic taxonomists agree that an organism's classification should reflect _______
phylogeny
Use division when talking about...
plants
Into what 2 taxa did Aristotle classify organisms?
plants and animals