Describe one way all students in this class can be separated into groups, or classified.

1. Describe one way all students in this class can be separated into groups, or classified.

3. Aristotle (384BC-322BC) developed the first classification system, which divided all known organisms into two groups: PLANTS and ANIMALS.

4. Aristotle then divided each of these main groups into 3 smaller groups. Animal Subgroups: Land, Water, Air Plant Subgroups: Small, Medium, Large

5. Scientists have identified more than 2.5 million different organisms. And their job isn’t even close to being finished! Some biologists estimate that there may be at least 7 million different kinds of organisms living in tropical rain forests and in the depths of Earth’s oceans. No wonder why we need to classify!

6. Classification • Grouping of different types of organisms based on similar characteristics

7. Taxonomy • Branch of biology that deals with classification of living things

8. Carolus Linnaeus (1707-1778) like Aristotle, classified organisms according to their traits. The classification systems of both Aristotle and Linnaeus started with the same two groups: Plants and Animals. Linnaeus called these groups kingdoms. But, unlike Aristotle, Linnaeus divided kingdom into 5 levels. Organisms were placed in these levels based on traits, including similarities of body parts , physical form such as size, shape, and methods of getting food.

9. Classification system used today • Carolus Linnaeus (1700’s) • All organisms are divided into 7 levels of classification

10. Largest group • Very diverse Kingdom Phylum Class Order Family Genus Species Smallest groups and most closely related to each other

12. Kings Play Chess On Fine Green Stools

14. Species • One kind of organism that can mate with each other & produce fertile offspring

15. Kingdom Phylum Phylum Phylum Phylum Phylum Phylum

17. Naming organisms Before Linnaeus developed his naming system, plants and animals were named by a series of Latin words that described the physical appearance of the organism. This was very confusing. For example, let’s look at the first name of the honey bee. Apis pubescens, thorace subgriseo, abdomine fusco, pedibus posticis glabris utrinque margine ciliatus. This means “fuzzy bee, light gray middle, brown body, smooth hind legs that have a small bag edged with tiny hairs.” Linnaeus named it Apis mellifera which means “honey-bearing bee.”

18. Binomial Nomenclature • Method used to name organisms • Devised by Linnaeus • 2 names • Genus species

20. Humans = Homo sapiens

21. Canis lupus

22. Let’s summarize… How are organisms classified in the classification system used today? Explain the difference between a kingdom and a species. Explain the method used for naming organisms. In a dichotomous key, how many descriptive statements are found in each step? When starting a dichotomous key, which step do you start with? What do you do if the first statement is false?

23. Review: 1. Which of the following places the seven major classification groups in order from largest to smallest? (1.) phylum, class, kingdom, order, family, genus, species (2.) kingdom, phylum, class, order, family, genus, species (3.) kingdom, phylum, order, family, class, genus, species (4.) genus, species, class, order, kingdom, family, phylum

24. 2. The scientific name for a lion is Panthera Leo. The word Panthera tells us the lion’s (1.) kingdom (2.) phylum (3.) genus (4.) species

25. 3. Members of a population of gray squirrels, Sciurus carolinensis, are classified in the same species because they (1.) obtain their food in the same manner (2.) produce enzymes by synthesis (3.) can mate and produce fertile offspring (4.) live in the same area

26. 4. In today’s classification system, 2 organisms would be most closely related if they were classified in the same (1.) kingdom (2.) phylum (3.)genus (4.)species

27. 5. Which classification category contains the greatest number of different types of organisms? (1.) kingdom (2.) phylum (3.) genus (4.) species

28. Dolphin  Tursiops truncatus

29. Raccoon  Procyon lotor

30. Fruit flyDrosophila melanogaster