220 likes | 368 Views
CH 6.2 and CH 7. Species Change Over Time and Classification of Living Things. Evolution. Evolution is defined as change over time It is the result of changes in the genetic material that are passed from generation to generation
E N D
CH 6.2 and CH 7 Species Change Over Time and Classification of Living Things
Evolution • Evolution is defined as change over time • It is the result of changes in the genetic material that are passed from generation to generation • (#23) Organisms use adaptations to have a better chance of surviving and reproducing
History • Lamarck was on of the first scientists to suggest the idea of change over the lifetime of an organism (Giraffes Necks) • Darwin studied plant and animal species on the Galapagos Islands (178 islands) • He noticed that species were different from island to island • Looked at adaptations to certain environments • Looked at finches and their feeding behaviors
Artificial Selection • When people (breeders) produce new varieties of animals over time • Select a certain desired trait • Breed two animals displaying that trait • The result is offspring displaying the trait
Natural Selection • (#15) Darwin proposed the same thing was happening naturally in the animal and plant world • (#16) He based his ideas on 4 principles: • Overproduction: When a species produces more offspring than can live in the environment • Variation: mutations that naturally occur in the genetic material • Adaptation: any inherited trait that gives an organisms an advantage to survive • Selection: if a trait helps an organism survive to reproduce, the trait has been “selected”
Speciation • (#27) The evolution of new species from an existing organism • Can occur when the environment changes dramatically such as a volcanic eruption • New species can also occur when the environment changes gradually
Formation of New Species due to Isolation Example from a population of Cichlids (fish) • Water level is low, one species lives in a lake • Level rises filling shoreline, population spreads throughout the lake • Level falls, isolating the fish from each other • New species development that are more successful in their environment
Isolation Can Lead to New Species • Scientist believe that Isolation is essential to speciation • Isolation can occur due to geographic changes such as mountains building up • Cases caused by isolation have led to the great level of biodiversity on Earth
CH 7 Classification of Living Things
1600’s: organisms were classified based on appearance and behavior • PROBLEM: Can be deceiving, (#7) not universal (i.e. they could not ALL agree on a system for naming organisms) • 1700’s: 2 Kingdoms (Plant and Animal) • Linnaeus set a standard 2 name system for each animal (Genus species) • Linnaeus developed a system for naming species and organizing them into groups (#24) • 1866: 3 Kingdom Sytem (plant, animal, protista) • 20th Century: (21)Started using DNA and genes to classify related species • 1925: 2 Kingdoms (Prokaryota & Eukaryota) • 1938: 4 Kingdoms (Monera, Protoctista, Plantae, Animalia) • 1969: 5 Kingdom System (Monera, Protista, Plantae, Fungi, Animalia) • 1977: Current 6 Kingdom System • 2000’s:???? 7 Kingdoms???? No Kingdoms??? Domains??
Classification • (#5) Classification is the process of arranging organisms into groups based on similarities • Taxonomy: science of naming and classifying organisms • To classify organisms scientists use similarities and differences among species • A classification system (such as one found in a field guide (#36) can help you identify unfamiliar organisms • A taxon is a group of organisms that share certain traits based on shared ancestors. • Not All organisms that look alike are closely related
Binomial Nomenclature • Each organism has a 2 part name • Scientific name • Written in Latin and Greek • Genus species • Genus: a group of species with similar characteristics • Species: the specific name for the organism (contains the least number of organisms) • EX) Homo sapiens (human), Aubrietagracilis (flower), Chameleogracilis (chameleon), Mammillariagracilis (cactus)
7 Levels of Classification to Name a Species • Each level is more specific than the last • Kings Play Chess On Fat Green Stools • Kingdom • Phylum • Class • Order • Family • Genus • Species
Dichotomous Keys • Asks a series of questions that can be answered in only two ways. • Each answer leads to another question until you identify the organism
KEY TO THE CRITTERS ON BEBONK 1. Has 1 hair………………………………………………..2 Has 2 hairs………………………………………………4 2. Has a belly button…………………………………BIP Has no belly button………………………………3 3. Has 2 legs………………………………………………GLIP Has 4 legs……………………………………………FOOP 4. Has arms…………………………………………….GLOP Has no arms……………………………………….NOP
Kingdom Plantae • Multicellular • Live on water and land • Obtain energy from sunlight • Have a nucleus, cell wall, chloroplast • EX) grass, trees, moss
Kingdom Animalia • Multicellular • Live on water and land • Obtain energy by eating food • Have a nucleus, no cell wall, no chloroplast • Have the ability to move • EX) human, elephant dog, fish bugs
Kingdom Protista • Most are unicellular • Nucleus • Have the ability to move • Some eat like animals • Some get energy from sunlight • EX) Sea weed, Kelp, Euglena
Kingdom Fungi • Takes nutrients from environment • Rooted in one place • Have cell walls • Act as decomposers • EX) Mushroom, yeast, molds
Kingdom Archaea • No Nuclei • Live in extreme environments-high heat, high salt, high sulfer • EX) Methanococcoidesburtonii
Kingdom Bacteria • Unicellular • No Nuclei • Reproduce by dividing in two • Can move • EX) E. Coli