Biology 14.1 Classification of Organisms

1. Biology 14.1 Classification of Organisms Classification of Organisms

2. Taxonomy • Just as it is impossible for postal workers to sort mail by only a person’s name; it is impossible for biologists to memorize every name of the 10-30 million organisms on Earth. • To sort mail, a postal worker first sorts by zip code, than by street number, than by name. • In the same way, biologists sort organisms into large categories, than split those categories into other categories, and continue sorting into smaller and smaller more specialized categories.

3. Taxonomy • More than 2000 years ago, the Greeks grouped plants and animals according to their structural similarities. • Later Greeks and Romans grouped plants and animals into basic categories such as oaks, dogs, horses, birds, fish and so on. • Eventually each unit of classification came to be called a genus; the Latin word for “group” • Starting in the Middle Ages, genera were named in Latin.

4. Taxonomy • The science of naming and classifying organisms is called taxonomy. • Until the mid-1700s, biologists named organisms by adding descriptive phrases in Latin to the name of the genus. • The name of the European honeybee was Apispubescensthoracesubgriseoabdominefuscopedibusposticicglabisuntrinquemargineciliatus. • These names became so long that they become difficult to use and not everyone used the same name. A simpler solution needed to be developed.

5. Taxonomy • In the 1750s, a simpler solution was developed by a Swedish biologist, Carl Linnaeus. • Linnaeus developed a naming system that used only two words for each species; a system called binomial nomenclature • This two part name system became popular among scientists and is used today under the title “scientific name”. • The scientific name for the same honeybee is Apis mellifera; much shorter than the previous old system and easier to remember.

6. Taxonomy • The first word in the two-part name of a scientific name is the genus. • A genus is a category of taxonomy that contains similar species. • Organisms in a genus share similar characteristics. • For example the genusQuercus is composed of different kinds of oak trees. • The second word in a scientific name identifies one particular kind of organism within the genus called a species. Genus Quercus Quercus Palustris

7. Taxonomy • The first letter of a genus name is always CAPITALIZED and the first letter of the species name is always lowercase. A scientific name is also always italicized or underlined. • For example: Quercus is the genus name for oak trees • Quercus rubrais the name for a red oak. • Quercus phellosis the name for a willow oak. • Quercus is the genus name ; phellos and rubra are the species names Genus Quercus Quercus Palustris

8. Taxonomy • The scientific name of an organism gives biologists worldwide a way to talk about the same animals while using different languages. It is a universal naming system. • The name given to a species must conform to the rules established by an international commission of scientists, • All scientific names must have two Latin words or terms created according to the rules of Latin grammar. • To the right are newly discovered species of spiders named for rock-stars Neil Young and David Bowie Jason Bond, an ECU professor of biology, has named a newly discovered trapdoor spider, Myrmekiaphilaneilyoungi, after the legendary rock star. Heteropodadavidbowie

9. Domain Classifying Organisms Linnaeus worked out a system of classifying plants and animals in which an organism’s form and structure are the basis for ranking. The different groups that all organisms fall into can be arranged by 8 levels. Speciesare at the bottom. Remember species are a group of similar organisms that are capable of interbreeding. A member of a species can breed with another member of the same species.

10. Domain Classifying Organisms • All species are members of a genus; a larger group that contains many species similar to each other. • Remember that our 2 part scientific name lists the genus than the species. • For example, Partherapardusis the scientific name for a species of panther. • Pardus is the species name and panthera the genus name . • Similar genus are collected into a family. The family Felidae at right houses all varieties of felines (cats large and small; housecats to lions)

11. Domain Classifying Organisms • The family of felines is part of a larger order.An order has many families in it. • The orderin the example at right is the order of carnivorawhich contains carnivores (meat eaters) • An order always contains similar families.

12. Domain Classifying Organisms • After order comes class. A classhas many different ordersunder it. • In the example at right; the class is mammalia (mammels) • The order of carnivora is just one of many orders that fall under the class ofmammalia

13. Domain Classifying Organisms • Classes with similar characteristics are grouped together into a phylum. • The classof mammalia at right is just one of the many classes that make up the phylum of chordata

14. Domain Classifying Organisms • The next step up the ladder is the kingdoms. • Many phylums that are similar are grouped together into a kingdom. • In the example at right the phylumchordata is just one of several phylum in the kingdom of animalia (animals)

15. Domain Classifying Organisms • Last, but not least, all kingdoms are grouped together into a domain. • All living things are grouped into one of three domains. • Two domains, Archaea and Bacteria, are each composed of a single kingdom of prokaryotes. • The third domain, Eukarya, contains all four kingdoms of the eukaryotes.

16. Domain Classifying Organisms • In order to remember the 8 categories in order, it is useful to memorize a phrase. • Do Kindly Pay Cash Or Furnish Good Security is a helpful way to remember the order of • Domain • Kingdom • Phylum • Class • Order • Family • Genus • Species

17. Domain Classifying Organisms • Scientific names are powerful because they tell us much about an organism. • Each level of classification is based upon characteristics shared by all members of the classification. • For example; the ordercarnivora contains all members that eat meat; ie are carnivores. • The classmammalia contains all members that are mammels. • The family felidae contains all members that are felines (types of cats ranging from housecats to lions)

18. Classifying Organisms • For another example; let’s look at the classification of a common honeybee. • The honeybee’s scientific name, Apis mellifera, indicates it belongs to the genusApisand the speciesname is mellifera. Together they give us the scientific name of the genus-species combined. • Genus: Apis- All members of this genus are actually honey bees, living alone or in hives

19. Classifying Organisms • Family: Apidae- Honey bees are members of the group Apidae because they have a corbicula (pollen basket) on the outside of each hind appendage.

20. Classifying Organisms • Order: Hymenoptera- Honey bees are members of the group Hymenoptera because they have “membranous wings, and their abdomen's first segment is fused with the last segment of the thorax.

21. Classifying Organisms • Class: Insecta- Honey bees are members of the Insecta because: they don't have any muscles past the first segment of their antenna; they have something called Johnston's organ; and they have an internal structure inside the head called a tentorium.

22. Classifying Organisms • Phylum: Arthropoda- Honey bees are members of the Arthropoda because they have segmented bodies and a jointed exoskeleton.

23. Classifying Organisms Kingdom: Animalia- Honey bees are members of the Animalia because they are, multicellular, heterotrophic and motile at some point in life. Domain: Eukaryota- Honey bees are members of the domain Eukaryota because their cells have a membrane-bound nucleus

24. Classifying Organisms Do Kindly Pay Cash Or Furnish Good Security Domain Kingdom Phylum Class Order Family Genus Species