Presentation on theme: "History of Life and the Origin of Species"— Presentation transcript:
1History of Life and the Origin of Species Mrs. StewartHonors biologyCentral Magnet School
2Standards:CCSS ELAI can trace the historical development of the theory of evolutionI can summarize the evidence for the theory of evolutionCCSS ELAI can critique and evaluate competing evolutionary arguments based on scientific knowledge, empirical evidence and logical arguments regarding relevant factors.
3Objectives (today, I will…) Differentiate between spontaneous generation and biogenesisDifferentiate between Charles Darwin and Jean-Baptiste Lamarck
4Choose… But choose wisely. Decide which partner is the bird and which is the cat.
5History of Life Biogenesis: Spontaneous Generation: All living things come from other living thingsSpontaneous Generation:Living things could arise from nonliving things
6Redi’s experiment Previous idea: Flies were created from rotten meat Redi: Meat kept away from adult flies would not produce maggots
7Spallanzani & PasteurSpallanzani – tried to disprove that microorganisms arose from a “vital force” in the airPasteur – improved spallanzani’s experiment to eliminate the flaw of “no air”
8CatsTell your bird how Pasteur improved upon Spallanzani’s experiment to disprove spontaneous generation
9Endosymbiosis Where/how did mitochondria get their own DNA? How did chloroplasts become so specialized?Theory of Endosymbiosis:Aerobic prokaryotes were engulfed by eukaryotic cells evolved into mitochondria (which perform aerobic respiration)Photosynthetic prokaryotes were engulfed by plant cells and evolved into chloroplasts (where photosynthesis occurs)
10Ch. 15.1 – 15.2 History of Evolution Mrs. StewartHonors BiologyCentral Magnet School
11What is Evolution? Dictionary: The gradual development/change of something; especially from a simple to complex form.Text book:(In biology) Generally, the process of change by which new species develop from pre-existing species over timeEvolution of Dance
12BirdsTell your cat what Evolution means. Give an example (not one that Mrs. Stewart used)
1318th Century Ideas 19th Century Ideas About living species: About the Earth:UniformitarianismAll species were permanent and unchanging.Earth was only a few thousand years old and unchanging.19th Century IdeasIdea by Charles Lyell that said geologic processes happed slowly over time and that some features of the Earth may take millions of years to form.
14CatsGive your bird an example to support Lyell’s theory.
15Jean-Baptiste Lamarck French Naturalist1809Lamarck’s Hypothesis: by selective use or disuse of organs, organisms acquire or lose certain traits. These traits could then be passed on to their offspring.Lamarck believed over time, this process led to change in a species.
16Lamarck’s Hypothesis1. Tendency toward perfection - All organisms have an innate tendency toward complexity and perfection, so they are continually changing to be more successful in their environment 2. Use and disuse - Organisms can alter their bodies/organs by use or disuse 3. Inheritance of acquired traits - Organisms can pass on those altered body parts/organs to the offspring
20Lamarck the Loser First to develop a hypothesis of evolution First to realize organisms adapt to their environmentBut, Behavior has no effect on inheritable characteristics
21Ch. 15.1 – 15.2 History of Evolution Mrs. StewartHonors BiologyCentral Magnet School
22Charles Darwin1809 – 1882Naturalist – study of nature and the natural worldSailed on the HMS Beagle in 1831Every time the ship docked, Darwin went ashore to collect plant and animal specimens
23Darwin’s observations piqued his interest in the diversity of life he observed. Darwin even found evidence that suggested species once present on earth had vanished.Researchers today speculate that 99.9% of all species that ever inhabited earth are now extinct.
24Galapagos IslandsThe islands were close together, but had very different climatesSmallest and lowest islands = hot, dry & barrenHood Island = sparse vegetationHigher islands had greater rainfall and a different assortment of plants/animalsIsabella Island = rich vegetationLand Tortoise shell shapes could be used to identify which island it inhabited
25What observations can YOU make about these species of land tortoise? Hood Island TortoisePinta Island TortoiseWhat predictions can YOU make about the island environment for each tortoise?What observations can YOU make about these species of land tortoise?Isabella Island Tortoise
26Which island would you predict has only low-lying vegetation? Hood Island TortoisePinta Island TortoiseWhich island would you predict has only low-lying vegetation?Isabella Island Tortoise
27Darwin’s IdeaDarwin observed that the plants and animals varied noticeably among the different Galapagos Islands.However, Darwin wondered if animals living on different islands had once been members of the same species – originating from the same South American ancestor
28Darwin’s FinchesDarwin observed many different types of “finch” and noticed several different beak shapes.Why?He began to notice different shaped beaks were “adaptations” for different food sources
29Religion’s Role Darwin was a devout Catholic He knew that his ideas, based on what he observed would provoke the catholic churchHe debated over what to do for 25 years.
30Darwin’s Theory – Descent With Modification The Origin of Species by Means of Natural Selection – 1858Every species – living or extinct – descended by reproduction from preexisting speciesANDSpecies must be able to change over time
31Mrs. Stewart Honors biology Central Magnet School Natural SelectionMrs. StewartHonors biologyCentral Magnet School
32Review What was Lamarck’s hypothesis? What did Darwin believe? Inheritance of acquired traitsSpecies changed as environment changed – adaptation and survival of the fittest
33Standards:CCSS ELAI can trace the historical development of the theory of evolutionI can summarize the evidence for the theory of evolutionCCSS ELAI can critique and evaluate competing evolutionary arguments based on scientific knowledge, empirical evidence and logical arguments regarding relevant factors.
34Objective (Today I will…) Explain the idea of “natural selection” and determine “fittest”Examine how adaptations help animals survive better
35Darwin’s reasoning for Natural Selection Overproduction – more offspring are produced than can survive due to competition for resourcesGenetic Variation – within a population, individuals have different traits. New traits may appear spontaneously.Struggle to survive – constant competition may cause some variations/traits to be advantageousDifferential Reproduction – Organisms with the best adaptations will survive and reproduce, thus the advantageous adaptations will become most prevalent in the population.
36Evolution by Natural Selection Struggle for existence – each member of a species competes regularly for food, living space and other necessities of life.main needs: Food, water, living space and ability to reproduceWho wins?
37Think – Pair – ShareHow can we describe Natural Selection in just 4 words?
38Survival of the Fittest How well suited an organism is to it’s environmentDoes fittest mean strongest?Does fittest mean in the best shape?Fitness – the ability of an individual to survive and reproduceThe result of adaptations
43Survival of the Fittest Fittest – the individuals most capable to survive and reproduce for multiple generationsThe traits selected as the most useful for survival and reproduction are determined by the organisms environmentNatural Selection accounts for Descent with Modification as species become better adapted to different environments.
44BirdsExplain to your cat how the environment can determine fitness – use a specific plant or animal as an example.(Not one Mrs. Stewart gave you)
45What is a Population?A group of organisms of the same species, that live in the same area, AND that interbreed
46Adaptation vs. Acclimatization Adaptation - Changes in traits in populations over timeExample: White moth population becoming a black moth population after 5 generations.Acclimatization – individual organism changes physiologicallyExample: growing thicker fur in winter
47AdaptationsAny inherited characteristic that increases an organism’s (and therefore, a populations) ability to survive and reproduceAnatomical or structural characteristicsPorcupine quills - protectionLonger necks in giraffes – find foodPhysiological processesHow a plant performs photosynthesisInstinctual BehaviorsHunting in packsLiving in burrows
49Can You… Differentiate between biogenesis and spontaneous generation Differentiate between Charles Darwin and Jean-Baptiste LamarckExplain the idea of “natural selection” and determine “fittest”
50Mrs. Stewart Honors Biology Central Magnet School Evidence of EvolutionMrs. StewartHonors BiologyCentral Magnet School
51Standards:CLE – Explain how genetic variation in a population and changing environmental conditions are associated with adaptation and the emergence of new species.
52Descent with Modification Over long periods of time, natural selection produces organisms with different structures, niches or occupy different habitats than their ancestors.Each living species has descended, with changes, from other species over time.Result: species today look/act different from their ancestors
53Common DescentLook back: Tigers, panthers and cheetahs all share a common ancestorLook back further: you will find ancestors that these cats share with horses, dogs and bats.Farther back: common ancestors of mammals, birds, alligators and fishes.Logic: looking far enough back we should find the common ancestor for all living things
55Evidence of Evolution Homologous & Analogous Structures Fossil Records Vestigial StructuresEvidence of EvolutionComparative EmbryologyMolecular Biology
56Fossil Records Fossils - preserved remains of ancient organisms Compare fossils from older layers and younger layers and show changes in species over time
57Fossil RecordsCompare fossils found around the world and we can infer when and where different organisms existed.Fossils also provide evidence about the environment in which the organism existed and for which the organism adapted
58Transitional SpeciesFossil records show species which have features that are intermediate between those of hypothesized ancestors and later descendant species
59Homologous vs. Analogous Structures Homologous – refers to structures that share the same basic structure but may differ greatly in functionAnalogous – refers to structures that vary greatly in structure but may share the same function
68Similarities in Embryology The early stages, or embryos, of many animals with backbones are very similar.Does this mean that a human embryo is ever identical to a fish, or a bird embryo?NOBut, many embryos look especially similar during early stages of development.
70Comparative Embryology What do these similarities mean?The same groups of embryonic cells develop in the same order and in similar patterns to produce the tissues and organs of all vertebrates.
71All animals go through this process Its at the blastocoel step that we differBlastopore could become mouth or anus, etc.
72The number of amino acids that differ from human hemoglobin Molecular BiologyUsing new technology, we can see how many DNA and RNA sequences organisms share in commonAmino acid sequences used to determine how closely related different species are.The number of amino acids that differ from human hemoglobin
73Molecular Biology Amino Acid Similarities Which two plants are the most closely related according to this chart?
74Assignment:Evidence of evolution dry lab activity packet
75Exit Ticket: Socrative.com Room Number: Stewart 348Question: How does the environment determine the “fittest” individual?