Taxonomy & Evolution-Part 1

Mrs. Rago

Organization Why do we organize things? How do we organize things? Biologist do this through classification

Group objects or information

Taxonomy Branch of biology that groups & names

organisms This is done based upon the different

characteristics of each organism The science of describing, naming, &

classifying organisms Allows us to organize groups of organisms

with other organisms that have similar characteristics

Taxon Also called Taxa (plural) Any particular group within a taxonomic system

Early Taxonomists Aristotle

Grouped organisms into 2 groups: plants & animals Then subdivided plants into 3 groups: herbs, shrubs, trees

& subdivided animals based upon where the animal lived or spent a great deal of time: on land, in the air, or in the water

This system worked for many organisms but was used only till another, better system was developed

Carolus Linnaeus Swedish botanist Grouped organisms based upon physical & structural

similarities between different organisms He also developed a two-word naming system= binomial

nomenclature Example: Homo sapiens (people), Felis catus (domestic cats)

The Linnaean System Developed by Swedish naturalist Carolus

Linnaeus Groups organisms into categories based upon

their form & structure Could have done this by behavior or types of food

that an organism eats. Consists of a Hierarchy

Similar to a ladder or pyramid

Linnaean System Hierarchy

Each level has smaller & smaller number of organisms in it

6 different Kingdoms Plants

Autotrophs, photosynthesis to make energy, most plants live on land

Animals Multicellular, develop from

embryos, heterotrophs, symmetrical body organization (most), most move around environment to capture food

Protista Eukaryotes (multicellular)

that are not plants, animals, or fungi

Fungi Eukaryotes, heterotrophs,

gain nutrients in a unique way

Archaebacteria Ancient bacteria

Bacteria Eubacteria (true bacteria)

Linnaean System Kingdom Phylum Class Order Family Genus Species

Examples of Organization

Domain- Eukarya Eukarya

Kingdom- Animalia Animalia Phylum- Chordata Chordata Class- Mammalia Mammalia Order- Carnivoria Carnivoria Family- Felidae Canidae Genus- Felis Canus Species- Felis catus Canus lupus

1 2

Our mystery animals

Felis catus Canus lupus

Binomial Nomenclature Linnaeus gave an organism 2 names

1 genus name & a species name This is an organisms scientific name Example: Homo sapiens (People); Felis catus

(domestic cat); Canis lupus familiaris (domestic dog)

Latin is the language of Scientific names Dead language

Dichotomous Key Uses pairs of contrasting, descriptive

statements to lead to the identification of an organism (or other object)

Can be used to tell different plants apart Poison ivy

What differences can you see?

How could a dichotomous key be useful? Medicine Botany Amateur Gardener

Arthropods Appendages

Body segments such as legs & antennae Chitin

Makes up the arthropod’s exoskeleton Exoskeleton

Skeleton on outside of body covers the skin

Compound eye Many lens

Mammals Endoderms

Maintain constant body temperature Hair Completely divided heart (four-chamber heart) Produce milk for their young Single jawbone

Compared to reptile’s jaw which is made up of many bones

Specialized teeth Teeth to crush, grind, slice, cut, hold prey, or crush

Reptiles Heart has 2 atria & single ventricle that is

partially divided by a septum Ectotherms

Regulate internal temperature by absorbing heat from surroundings

Reproduce by laying eggs

Fish Reproduce by releasing eggs & sperm into

water Gills to process oxygen from water Cartilaginous bones

Amphibians Skin is permeable to water & oxygen

Also breathe through lungs in addition to their skin Most species lay eggs in water & have an

aquatic larval stage Examples: frogs, toads, & salamanders

Birds Feathers Wings Lightweight rigid skeleton Endothermic Most efficient respiratory system of any

terrestrial vertebrate (air sacs occupy large portion of abdominal cavity- just store air & reduce bird’s density)

Beak Lay eggs in hard shell