1. Organizing Life’s Diversity
Honors Biology Ch. 17
Organizing
Life’s Diversity

2. I. The History of Classification
Taxonomy:
- the science of identifying, naming, and classifying organisms

3. A. Early Classification Systems
1. Aristotle:
a. Devised First Classification System
- Animals (red-blooded and bloodless)
- Plants (trees, shrubs, and herbs)
- 2 problems:
1) superficial categories
2) used common names

4. B. Disadvantages of Common Names:
1. Confusing
- ex. mountain lion, cougar, puma, panther, catamount
Puma concolor

5. 2. Misleading -. ex. starfish, jellyfish, cuttlefish,
2. Misleading - ex. starfish, jellyfish, cuttlefish, crawfish, silverfish

6. Microplitis demolitor
3. Language Problems - local names - names used by different languages - some organisms have no common name
Microplitis demolitor

7. 2. Carolus Linnaeus - developed modern classification system
- Swedish botanist (1700’s)
- 2 important innovations:

8. a. Binomial Nomenclature
- two-word naming system:
genus & species
- gives a unique, universal name for every species
Carolus Linnaeus

9. Honey Bee
Apis mellifera
Apis pubescens, thorace subgriseo, abdomine fusco, pedibus posticis glabris, utrinque margine ciliatus

10. 1) Genus: 2) Species: - 1st word, small group
- usually a Latin noun, capitalized
2) Species:
- 2nd word, particular type
- Latin adjective, lower case

11. 3) Examples:
- Homo sapiens humans
- Tyrannosaurus rex

12. 3) Examples: - Acer macrophyllum bigleaf maple - Acer rubrum red maple
- Acer saccharum sugar maple
Acer pennsylvaticum
Acer rubrum
Acer circinatum
Acer saccharum

13. 3) Examples: - Sequoia gigantum giant sequoia
- Tsuga heterophyllum western hemlock
- Pseudotsuga menziesii Douglas-fir

14. b. Hierarchy of Classification Groupings
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Eukarya
Animalia
Chordata
Mammalia
Carnivora
Canidae
Canis
lupus

15. b. Hierarchy of Classification Groupings
Did
King
Phillip
come
often
for
ginger
snaps?
Eukarya
Animalia
Chordata
Mammalia
Carnivora
Canidae
Canis
lupus
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

16. Hierarchy of Taxa

17. II. Taxonomy Today - Classification systems change constantly.
- Taxonomists do not always agree on how to classify organisms.

18. A. Determining Species 1. Typological Species Concept
- a group of organisms that are physically similar to each other

19. 2. Biological Species Concept
- a group of organisms that is able to interbreed and produce fertile offspring in a natural setting
- cannot be used with extinct or asexual organisms
Similarity between different species
Diversity within a species

20. 3. Phylogenetic Species Concept
- defines a species as a set of organisms with a unique genetic history

21. B. Characters
- inherited features (morphological or biochemical) that vary among organisms

22. 1. Morphological Characters
- similarities indicate common ancestry
- include homologous structures: different functions but have similar underlying anatomy

23. - does not include analogous structures: similar functions but different underlying anatomy
Eastern Mole
Marsupial ‘Mole’

24. 2. Biochemical Characters
- The greater the similarities in certain compounds (DNA, proteins, etc.), the more closely related organisms are.
Species
Human
Rhesus monkey
Mouse
Chicken
Frog
Lamprey
14%
54%
69%
87%
95%
100%
Percent of Amino Acids That Are
Identical to the Amino Acids in a
Human Hemoglobin Polypeptide
Comparison of a Protein Found in Diverse Vertebrates

25. A Molecular Homology

26. 3. Molecular “Clock”
- Mutations occur randomly and accumulate over time.
- Mutations that don’t affect survival can be used to estimate time.
The Constant Rate of Evolution of the α-globin

27. C. Phylogenetic Reconstruction
Phylogeny of Whales
C. Phylogenetic Reconstruction
- Phylogeny is the evolutionary history of a species.

28. 1. Character Types
- Ancestral characters are shared by ancestral organism and all of its descendents.
- Derived characters are shared by one group of organisms but not the ancestor.
Leopard
Hair
Amniotic egg
Four walking legs
Hinged jaws
Vertebral column
Turtle
Salamander
Tuna
Lamprey
Lancelet (outgroup)
Phylogenetic Tree of Chordates

29. 2. Cladograms (Phylogenetic Tree)
- a branching diagram that represent the proposed phylogeny of a group of organisms
Phylogenetic Tree of Dinosaurs

30. Phylogeny of Bears Ursininae Tremarclinae Ailuropodinae Ailuridae
Musteloidae
Procyonidae
Caniformia
Ursidae
Phylogeny of Bears

32. III. Domains and Kingdoms
- Most scientists today use the 3 domain system to classify organisms:
Bacteria, Archaea, and Eukarya.

33. The Three Domains of Life
Fungi
EUKARYA
Trypanosomes
Green algae
Land plants
Red algae
Forams
Ciliates
Dinoflagellates
Diatoms
Animals
Amoebas
Cellular slime molds
Leishmania
Euglena
Green nonsulfur bacteria
Thermophiles
Halophiles
Methanobacterium
Sulfolobus
ARCHAEA
COMMON
ANCESTOR
OF ALL
LIFE
BACTERIA
(Plastids, including
chloroplasts)
Green
sulfur bacteria
(Mitochondrion)
Cyanobacteria
Chlamydia
Spirochetes
The Three Domains of Life

34. A. Domain Bacteria - includes the kingdom Eubacteria
- prokaryotes whose cell walls contain peptidoglycan

35. B. Domain Archaea - Prokaryotes that represent an ancient form of life
- more closely related to our eukaryotic ancestors
- called extremophiles because they can live in extreme environments

36. C. Domain Eukarya - includes all eukaryotes - contains:
Kingdom Protista
Kingdom Plantae
Kingdom Fungi
Kingdom Animalia

37. 1. Kingdom Protista - eukaryotic organisms
- unicellular, colonial, or multicellular

39. 2. Kingdom Plantae - photosynthetic multicellular eukaryotes
- have cell walls made of cellulose
- nonmotile

40. 3. Kingdom Fungi - unicellular or multicellular eukaryote
- heterotrophic (absorb nutrients)
- have cell walls made of chitin
- nonmotile

41. 3. Kingdom Fungi - unicellular or multicellular eukaryote
- heterotrophic (absorb nutrients)
- have cell walls made of chitin
- nonmotile

42. 4. Kingdom Animalia - heterotrophic, multicellular eukaryotes
- complex organ systems
- motile
- obtain food by ingestion

43. The
End

44. - Order Carnivora

45. Linking Classification and Phylogeny
Species
Canis
lupus
Panthera pardus
Taxidea
taxus
Lutra lutra
latrans
Order
Family
Genus
Carnivora
Felidae
Mustelidae
Canidae
Lutra
Panthera

47. A Phylogenetic Tree of Birds and Their Close Relatives
Common
ancestor of
crocodilians,
dinosaurs,
and birds
Birds
Lizards
and snakes
Crocodilians
Ornithischian
dinosaurs
Saurischian

48. Hippidion and other genera
Phylogeny of Horses
Recent
(11,500 ya)
Pleistocene
(1.8 mya)
Pliocene
(5.3 mya)
Miocene
(23 mya)
Oligocene
(33.9 mya)
Eocene
(55.8 mya)
Equus
Hippidion and other genera
Nannippus
Pliohippus
Neohipparion
Hipparion
Sinohippus
Megahippus
Callippus
Archaeohippus
Merychippus
Parahippus
Hypohippus
Anchitherium
Miohippus
Mesohippus
Epihippus
Orohippus
Paleotherium
Propalaeotherium
Pachynolophus
Grazers
Browsers
Key
Hyracotherium