1. Linnaeus’ System of Taxonomy
Used a hierarchical system
Kingdom, Phylum, Class, Order, Family, Genus, Species (later Domain was added)
Based on molecular evidence (DNA and protein sequences) its accepted to have 6 Kingdoms and have added 3 Domains

2. Latinized descriptive names of organisms - Binomial Nomenclature: 2 word scientific naming system
First part of binomial – Genus – Always capitalized
Second part – species - always lower case.
Latin scientific names are always italicized (if word processing) or underlined (if hand written)
Ex. Homo sapiens, “wise man”
species – specific group of 1 type of organism that may interbreed and produce viable, fertile offspring.

3. Binomial Nomenclature – Who cares?
What do you call this?
Crawdad?
Crawfish?
Crayfish?
Prairie crayfish-Procambarus gracilis

4. Why use Binomial Nomenclature?
Problems with common names
Varies from area to area, therefore, no commonality.
Does not specify a particular species.
Each animal has an unique binomial name.
Required for all animals by International Code of Zoological Nomenclature.

7. Domain Archaea Domain Eubacteria
Prokaryotic microbes, tiny
Live in extreme environments: high temps, salts, & acids (tough)
Anaerobic
Most primitive
Prokaryotic microbes
Often called the “true bacteria”
Live in most environments
Anaerobic or aerobic

9. Domain Eukarya Eukaryotic Mainly aerobic but can be anaerobic
Includes all other kingdoms (Protista, Plant, Fungi, Animal)

10. 6 Kingdoms

11. Common Animal Phylum

12. What is this?

13. Most recently described Phylum - Cycliophora
36th found Phylum in 1995
In the Animal Kingdom
Symbion pandora
Found in mouthparts of Norwegian lobsters
0.3 mm long = 300 µm

14. Currently we use
Morphological, biochemical, fossil, and molecular comparisons to infer evolutionary relationships

15. Though sedimentary fossils are the most common
Paleontologists study a wide variety of fossils
(a) Dinosaur bones being excavated from sandstone
(g) Tusks of a 23,000-year-old mammoth, frozen whole in Siberian ice
(e) Boy standing in a 150-million-year-old dinosaur track in Colorado
(d) Casts of ammonites, about 375 million years old
(f) Insects preserved whole in amber
(b) Petrified tree in Arizona, about 190 million years old
(c) Leaf fossil, about 40 million years old

16. Morphological and Molecular Homologies
In general, organisms that share very similar morphologies or similar DNA sequences
Are likely to be more closely related than organisms with vastly different structures or sequences.
Not always true! Analogy vs. Homology

17. Homology
Homologous Structures – structures in different species that are similar because of commons ancestry.

18. Analogy
Analogous Structures – similarity in structures due to adaptations and not a common ancestor.

19. Cladograms

20. Cladistics
a method that applies the scientific method to the construction of evolutionary relationships.

21. Cladogram
Diagram showing how organisms are related based on shared, derived characteristics
such as:
vertebrae
jaw bones
four legs
amniotic eggs
hair

22. Cladogram Vocabulary Branch point Ingroup Outgroup
2 species differ in shared derived characters
Ingroup
monophyletic group we are interested in
Outgroup
species or group of species that is most closely related to an ingroup

23. Primate Cladogram

24. Each branch point
Represents the divergence (separation) of two species

26. What shared derived character is common to:
salmon
lizard
rabbit
but not the lamprey?

27. Constructing a cladogram
Choose species
Choose characters
Each character has different character states (example: tail or no tail)
Determine order of character states
primitive or derived?
Use the fossil record
Many simple parts came before fewer, more specialized parts
Vestigial organs –not functioning but present)
Mutation rate of DNA nucleotides
Group species (or higher taxa) based on shared derived characteristics

28. Constructing a cladogram
Build a cladogram based on
All species are placed on tips in the phylogenetic tree, not at branch points
Each cladogram branch point should have a list of one or more shared derived characters that are common to all species above the branch point unless the character is later modified
All shared derived characters appear together only once in a cladogram unless they arose independently during evolution more than once
Choose the most likely cladogram among possible options

29. Construct a Cladogram for Us
Construct a Cladogram for Us! Let’s use the characters of tail, fur, and # of limbs

30. Gorilla
Four limbs
Fur
No tail

31. Tiger
Four limbs
Fur
Tail

32. Lizard
Four limbs
Tail

33. Fish
Tail

34. Chimpanzee
Four limbs
Fur
No tail

35. Clade With 4 Limbs

36. Clade With Fur

37. Clade With No Tail

38. Characteristics (Traits) for Constructing this Cladogram
Tail is the most ancestral
Four limbs is the oldest derived trait
Fur is a later derived trait
Loss of tail is the most derived trait

39. One Possible Cladogram
Gorilla
Chimpanzee
Tiger
Lizard
Fish
Tail Lost
Fur
Four Limbs

40. A Vertebrate Cladogram
Birds
Mammals
Reptile
Amphibian
Fish
Four Limbs
Amniotic Egg
Endothermic
Fur
Feathers
Vertebrae
Lancelet
Outgroup

41. The outgroup comparison
Enables us to focus on just those characters that were derived at the various branch points in the evolution of a clade.
Salamander
TAXA
Turtle
Leopard
Tuna
Lamprey
Lancelet (outgroup) 1
Hair
Amniotic (shelled) egg
Four walking legs
Hinged jaws
Vertebral column (backbone)
Amniotic egg
Vertebral column
(a) Character table. A 0 indicates that a character is absent; a 1 indicates that a character is present.
(b) Cladogram. Analyzing the distribution of these derived characters can provide insight into vertebrate phylogeny.
CHARACTERS