1. Chapter 17
Classification
of Organisms

2. Until more recent times, scientists named
17-1 Finding Order
In Diversity
Until more recent times, scientists named
Things with crazy long names that
Just described the organism.
Apis pubescens, thorace subgriseo,
abdomine fusco, pedibus posticis
glabis, untrique margine cilatus.

3. The science of naming and classifying organisms is called taxonomy.
Until the mid-1700s, biologists named a particular type of organism by adding descriptive phrases to the name of the genus

4. A Simpler System
A simpler system for naming organisms was developed by the Swedish biologist Carl Linnaeus

5. Linnaeus’s two-word system for naming organisms is called binomial nomenclature
Over the past 250 years since Linnaeus first used two-part binomial species names, his approach has been universally adopted

6. Scientific Name
The unique two-part name for a species is now referred to as its scientific name
The first word is the genus to which the organism belongs. A genus is a taxonomic category containing similar species

7. With Linnaeus’ system, the honey bee Is now called Apis mellifera.
The second word in a scientific name identifies one particular kind of organism within the genus, called a species. A species is the basic biological unit in the Linnaean system of classification
With Linnaeus’ system, the honey bee
Is now called Apis mellifera.

8. Similar genera are grouped into a family
Similar families are combined into an order
Orders with common properties are united in a class

9. Classes with similar characteristics are assigned to a phylum
Similar phyla are collected into a kingdom
Similar kingdoms are grouped into domains

13. 17-2 The 6 Kingdoms
What Is a Species?
In 1942, the biologist Ernst Mayr of Harvard University proposed a biologically based definition of species, which is called the biological species concept

14. Only about 1.5 million species have been described to date
Number of Species
The number of species in the world is much greater than the number described
Only about 1.5 million species have been described to date
Scientists estimate that 5 million to 10 million more species may live in the tropics alone

15. Evolutionary History
Classification based on similarities should reflect an organism’s phylogeny, that is, its evolutionary history
Through the process called convergent evolution, similarities evolve in organisms not closely related to one another, often because the organisms live in similar habitats

16. Phylogenic Diagram of Mammals
Similarities that arise through convergent evolution are called analogous characters
Phylogenic Diagram of Mammals

17. Cladistics
Cladistics is a method of analysis that reconstructs phylogenies by inferring relationships based on shared characters

18. A biologist using cladistics constructs a branching diagram called a cladogram, which shows the evolutionary relationships among groups of organisms
Organisms that share derived characters, are grouped together on the cladogram

19. Cladogram: Mammals,
Reptiles, and Birds

20. Cladogram: Major Groups of Plants

21. Evolutionary Systematics and
Cladistic Taxonomy

22. Bacteria, Archaea, Eukarya
There are 3 domains….
Bacteria, Archaea, Eukarya
Eukarya has 4 kingdoms…
Protista, Fungi, Plantae and Animalia

23. Kingdoms are the 2nd largest Taxonomic group of organisms.
Biologists groups organisms in the
Different kingdoms based on
Their similarities.

24. Most biologists use the 6
Kingdom system…
Eubacteria
Archaebacteria
Protista
Fungi
Plantae
Animalia

25. Characteristics of Eubacteria
Eubacteria have strong cell walls
Made of peptidoglycan.
The entire gene is circular and is
Transcribed as a single mRNA.

26. Eubacteria include species that Normally live in/on your body.
Kinds of Eubacteria
Eubacteria include species that
Normally live in/on your body.
Eubacteria are grouped based
On their shape.

27. Characteristics of Archaebacteria
Archaebacteria are distinguished
From eubacteria based on their
Metabolic differences.
The cell wall of archaebacteria do not
Contain peptidoglycan, instead they
Use lipids.
The genes are very similar to those
Of the eubacteria.

28. Kinds of Archaebacteria
There are at least 3 major groups
Of extremophiles.
Methanogens obtain their energy
By making methane gas.
Thermophiles live in very hot water,
Usually around 170°F!
Halophiles live in very salty places.

29. One of the 6 kingdoms, Protista, Is the most diverse.
Protists are defined on the basis
Of a single characteristic:
They are eukaryotes that are
Not fungi, plants, or animals.
Most are unicellular.

31. Fungi are mostly multicellular.
Fungi exist mainly in the form of
Slender filaments barely visible with
The naked eye called hyphae.
Fungus cells have an exterior wall
Made of Chitin, the same stuff
As crab shells.

33. Unlike many other organisms, plants Cannot move, it is the seeds that
Allow for the dispersal of plants.
Since plants are autotrophs, they
Are primary producers.
(photosynthesis)
Plants vary in size from the
1mm duckweed, to the 80m tall
Great sequoia.

34. Nonvascular plants developed without A system of transport. Mosses.
4 kinds of plants
Nonvascular plants developed without
A system of transport. Mosses.
Vascular plant have a large system
Of vascular tissues that allow for
The transport of water and nutrients
From their roots to the tops.

35. Seedless vascular plants have Roots, stems, and leaves, but
No seed, only spores. (ferns)
Nonflowering plants are called
Gymnosperms. They reproduce by
Making seeds, but have no flowers.
(pine trees)

36. Flowering seed plants produce Flowers and seed and are called
Angiosperms.
(roses, grasses, fruit trees)

38. Almost all animals are invertebrates, Which means that they
Do not have a backbone.
Of the more than 1 million living
Species, only have a backbone
And are referred to as vertebrates.

39. The animal kingdom includes about 35 phyla, most live in the sea.
Animals are very diverse in form and
Size. There are 0.5mm dust
Mites and blue whales that are
30 m long and weigh 220 tons!

41. THE END