1. The science of naming and classifying organisms
Taxonomy
The science of naming
and classifying organisms
Chapter 17

2. Carl Linnaeus developed the scientific naming system still used today
Binomial nomenclature is a two-part scientific naming system.
uses Latin words
scientific names always written in italics or underlined
two parts are the genus name and species descriptor

3. Tyto alba and Quercus alba
Are these species related?

4. Barn owl:
Tyto alba
White oak: Quercus alba

5. A genus includes one or more physically similar species.
Species in the same genus are thought to be closely related.
Genus name is always capitalized.
A species descriptor is the second part of a scientific name.
always lowercase
always follows genus name; never written alone

6. Ursus maritimus Ursus maritimus Ursus arctos horribilis
(horribilis is the subspecies)

8. Match the Latin names with the descriptions
Big-horned sheep from Canada
Bird with blue-green wings
House sparrow
Tree with large flowers
Plant that has flower with six petals
Cyanopica cyana
Passer domesticus
Ludwigia hexapetala
Ovis canadensis
(e) Magnolia grandiflora

9. Scientific names help scientists to communicate.
Some species have very similar common names.
Some species have many common names.

10. Linnaeus’ classification system has seven levels.

11. How can you remember these levels?
Kingdom __________
Phylum __________
Class __________
Order __________
Family __________
Genus __________
Species __________

12. Cladistics is classification based on common ancestry.
Phylogeny is the evolutionary history for a group of species.
evidence from living species, fossil record, and molecular data
shown with branching tree diagrams

13. derived traits are shown with numbers 1-4 - organisms are shown with letters A-D

14. Sample Cladogram

15. 1) Which traits do the Sinornis and Velociraptor share?
2) Which animal has arms as long as legs?
3) Does the Allosaurus have down feathers?

16. Make a cladogram for quarter, dime, nickel, penny

17. Make a cladogram
Alligator: amniotic egg, bones, four limbs, jaws, vertebrae
Frog: bones, four limbs, jaws, vertebrae
Gull: amniotic egg, bones, feathers, four limbs, jaws, vertebrae
Lamprey: vertebrae
Shark: jaws, vertebrae
Swordfish: bones, jaws, vertebrae

20. Dichotomous keys

21. 1 a) oval leaf: go to 2
b) lobed leaf: go to 5
2 a) leaf w/smooth edge: go to 3
b) leaf w/serrate or “sawtooth” edge: go to 4
3 a) leaf 10 to 15 cm long magnolia
b) leaf 4 to 7 cm long common pear
4 a) leaf 10 to 15 cm long Spanish chestnut
b) leaf 4 to 7 cm long white elm
5 a) four or five lobes: go to 6
b) many lobes: go to 7

22. 1 a) oval leaf: go to 2
b) lobed leaf: go to 5
2 a) leaf w/smooth edge: go to 3
b) leaf w/serrate or “sawtooth” edge: go to 4
3 a) leaf 10 to 15 cm long magnolia
b) leaf 4 to 7 cm long common pear
4 a) leaf 10 to 15 cm long Spanish chestnut
b) leaf 4 to 7 cm long white elm
5 a) four or five lobes: go to 6
b) more than 5 lobes: go to 7

23. 6 a) four pointy lobes . . . . . tulip tree
b) five pointy lobes: go to 8
7 a) lobes pointy red oak
b) lobes rounded English oak
8 a) star-shaped leaf sweetgum tree
b) leaf not star-shaped Japanese maple

25. Common Latin noun endings
-a, -us, -um, -ae, -i, -is, -o

26. Molecular clocks use mutations to estimate evolutionary time.
Mutations add up at a constant rate in related species.
As more time passes, there will be more mutations.
Mutations add up at a fairly
constant rate in the DNA of species that evolved from a common ancestor.
Ten million years later—
one mutation in each lineage
Another ten million years later—
one more mutation in each lineage
The DNA sequences from two
descendant species show mutations
that have accumulated (black).
The mutation rate of this
sequence equals one mutation
per ten million years.
DNA sequence from a
hypothetical ancestor

27. Mitochondrial DNA is used to study closely related species.
mutation rate ten times faster than nuclear DNA
passed down unshuffled from mother to offspring
grandparents
parents
child
Nuclear DNA is inherited from both
parents, making it more difficult to
trace back through generations.
Mitochondrial DNA is
passed down only from
the mother of each generation,so it is not subject to recombination.
mitochondrial
DNA
nuclear DNA

28. Mitochondrial DNA

29. Evidence for molecular clock in Hemoglobin
Quoll = Large carnivorous marsupial

30. The current tree of life has three domains.

31. Classification is always a work in progress.
The tree of life shows our most current understanding.
New discoveries can lead to changes in classification.
Until 1866: only two kingdoms, Animalia and Plantae
Animalia
Plantae

32. Until 1866: only two kingdoms, Animalia and Plantae
1866: all single-celled organisms moved to kingdom Protista
Protista

33. Until 1866: only two kingdoms, Animalia and Plantae
Protista
Plantae
1866: all single-celled organisms moved to kingdom Protista
1938: prokaryotes moved to kingdom Monera
Monera

34. Until 1866: only two kingdoms, Animalia and Plantae
Protista
Plantae
Animalia
1866: all single-celled organisms moved to kingdom Protista
1938: prokaryotes moved to kingdom Monera
Fungi
1959: fungi moved to own kingdom
Monera

35. Until 1866: only two kingdoms, Animalia and Plantae
Protista
Fungi
Plantae
1866: all single-celled organisms moved to kingdom Protista
1938: prokaryotes moved to kingdom Monera
Archea
Bacteria
1959: fungi moved to own kingdom
1977: kingdom Monera split into kingdoms Bacteria and Archaea

36. The three domains in the tree of life are Bacteria, Archaea, and Eukarya.
Domains are above the kingdom level.
proposed by Carl Woese based on rRNA studies of prokaryotes
domain model more clearly shows prokaryotic diversity

38. Domain Bacteria includes prokaryotes in the kingdom Bacteria.
one of largest groups on Earth
classified by shape, need for oxygen, and diseases caused

39. Domain Archaea includes prokaryotes in the kingdom Archaea.
cell walls chemically different from bacteria
known for living in extreme environments

40. Domain Eukarya includes all eukaryotes.
kingdom Protista

41. Domain Eukarya includes all eukaryotes.
kingdom Protista
kingdom Plantae

42. Domain Eukarya includes all eukaryotes.
kingdom Protista
kingdom Plantae
kingdom Fungi

43. Domain Eukarya includes all eukaryotes.
kingdom Protista
kingdom Plantae
kingdom Fungi
kingdom Animalia