1. Classification of Living Things Taxonomy and Cladograms

2. What is Taxonomy?  For millennia humans have created different ways to describe the living things on our planet.  At first our attempts to organize and classify animals were simple and based solely on their external appearance.  We now use a more complex system.

3. Why Do We Need to Classify Things?  The main reason is that knowing which species are related to each other, and how closely they are related, is very useful to the Scientific community.  If you were trying to find out what was wrong with a whale it would be useful to know that it is a mammal and not a fish.

4. Carolus Linnaeus

5. Carolus Linnaeus 1707 - 1778  Every recognized species on Earth is given a two-part scientific name. This system is called "binomial nomenclature."  Carolus Linnaeus (1707–1778) introduced the concept of binomial nomenclature in his great work called Systema Naturae.  In this book, nature was divided into three kingdoms: mineral, vegetable, and animals.  Linnaeus also established five ranks: class, order, genus, species, and variety.

6. Taxonomic Hierarchy  A Taxonomic hierarchy is very similar to a family tree.  Through it you can track how closely related each species is to each other.  Depending on how detailed you wish to be, this can be a simple tree chart, or a complex one (tolweb.org is an example of a complex one).

7. Do Kings Play Chess On Fine Glass Surfaces?  This year you will be responsible to remember the following taxonomic hierarchy:  Domain (Do)  Kingdom (Kings)  Phylum (Play)  Class (Chess)  Order (On)  Family (Fine)  Genus (Glass)  Species (Surfaces)

8. So How Does It Work?  Each level of the hierarchy has several groups and these groups each have specific characteristics required to be part of them.  If we found a new living organism we would compare its characteristics to these groups to see where it fits.  If it was endothermic (warm blooded), fed its young milk, had hair and gave live birth we would probably classify it as a mammal.

9. We Just Keep Learning  Since Linnaeus we have continued to add new groups to the taxonomic hierarchy.  As we continue to learn and develop new tools for investigation (like DNA analyses) we often have to change how we describe an organism from a taxonomic point of view.

10. Chimpanzee vs. Lion  Domain: Eukarya  Kingdom: Animalia  Phylum: Chordate  Class: Mammalia  Order: Primates  Family: Pongidae  Genus: Pan  Species: troglodytes  Domain: Eukarya  Kingdom: Animalia  Phylum: Chordate  Class: Mammalia  Order: Carnivora  Family: Felidae  Genus: Panthera  Species: leo

11. Comparative Taxonomy  By comparing the Chimpanzee to the Lion we can see that though they are very different creatures, they have some key things in common.  Both are animals with chordates (vertebrates) and mammals.  Yet one is a primate (apes and monkeys) and the other a carnivore (meat eaters).  Evolutionists use these similarities and differences to determine the relationships between species.

12. Broad to Specific  Each level of the taxonomic tree gets more and more specific.  Domain, Kingdom, Phylum and Class are very large groups with broad characteristics (we’re mammals too).  But by the time you get to Genus and Species the characteristics get very specific. See the next slide.

13. Cheetah vs. Lion  Domain: Eukarya  Kingdom: Animalia  Phylum: Chordate  Class: Mammalia  Order: Carnivora  Family: Felidae  Genus: Acinonyx  Species: jubatus  Domain: Eukarya  Kingdom: Animalia  Phylum: Chordate  Class: Mammalia  Order: Carnivora  Family: Felidae  Genus: Panthera  Species: leo

14. Comparative Taxonomy 2  As you can see the cheetah and lion share more in common than the lion and chimpanzee did.  Yet despite both being Felidae (cats) they are each part of a different Genus and a unique species.  The Species level is very specific.

15. Scientific Names  Each living creature on our planet has been given a Scientific name in Latin.  The Genus and Species of a creature are combined to create the Scientific name (thank you Linnaeus).  Panthera leo – lion  Acinonyx jubatus - cheetah

16. Why Latin?  Each living creature on the planet has several names. A lion is known as a leone in Italian and an ingonyama in Zulu.  This could lead to confusion amongst our world’s scientists.  Since Latin is a dead language, meaning it will never change as it is not actively spoken, scientists use it to name things.  This name means the same thing, no matter where you are on Earth.

17. Cladograms

18.  Cladograms are tree-like charts that generally show the evolutionary relationships between different creatures or taxonomic groups.  They can be drawn artistically, simply, or extremely complexly (tolweb.org).

19. Basic Cladogram for Great Apes HumanChimpanzeeBonoboGorilla Orangutan

20. Interpreting a Cladogram

21.  Some cladograms give extra details.  The one above showed that all three creatures possessed a backbone as they come after the trait.  However only the horse and human shared the placenta characteristic.  Thus humans are more closely related to horses than to fish in an evolutionary sense.

22. Resources  www.hawaii.edu www.hawaii.edu  www.torontozoo.com www.torontozoo.com  www.nationalzoo.si.edu www.nationalzoo.si.edu  www.tolweb.org www.tolweb.org