evolution chapter 15. what is evolution? a basic definition of evolution… “…evolution can be...
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EVOLUTION
Chapter 15Chapter 15
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What is evolution?
A basic definition of evolution…
“…evolution can be precisely defined as any change in the frequency of alleles within a gene pool from one generation to the next." - Helena Curtis and N. Sue Barnes, Biology, 5th ed. 1989 Worth Publishers, p.974
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So what does the definition mean?
Evolution is a change in the number of Evolution is a change in the number of times specific genes that code for specific times specific genes that code for specific characteristics occur within an interbreeding characteristics occur within an interbreeding populationpopulation
Individuals don’t evolve, populations doIndividuals don’t evolve, populations do There is no implied “improvement” in There is no implied “improvement” in
evolutionevolution
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So what does the definition mean?
Things don’t change because organisms Things don’t change because organisms want or need them to (Lamarkism)want or need them to (Lamarkism)
There is no difference between There is no difference between macroevolution and microevolution. macroevolution and microevolution. Macroevolution is merely a collection of Macroevolution is merely a collection of microevolution events.microevolution events.
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Definition problems
Part of the problem is Part of the problem is that a number of that a number of different definitions for different definitions for evolution can be found evolution can be found both within and without both within and without the scientific the scientific community. These can community. These can easily confuse easily confuse laypeople.laypeople.
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Definition problems
"evolution: The gradual process by which the present diversity of plant and animal life arose from the earliest and most primitive organisms, which is believed to have been continuing for the past 3000 million years."
-Oxford Concise Science Dictionary
"evolution: ...the development of a species, organism, or organ from its original or primitive state to its present or specialized state; phylogeny or ontogeny"
- Webster's
"evolution: ...the doctrine according to which higher forms of life have gradually arisen out of lower."
- Chambers
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Definition problems
In addition to being simply wrong, these definitions can cause confusion since it is common for non-scientists to enter into a discussion about evolution with such definitions in mind.
Charles Darwin
Darwin’s Theory of Evolution
EvolutionEvolution, or change over time, is the , or change over time, is the process by which modern organisms have process by which modern organisms have descended from ancient organisms. descended from ancient organisms.
A scientific A scientific theorytheory is a well-supported is a well-supported testable explanation of phenomena that testable explanation of phenomena that have occurred in the natural world.have occurred in the natural world.
Voyage of the Beagle
Voyage of Beagle
Dates: Dates: February 12th, 1831February 12th, 1831 Captain:Captain: Charles Darwin Charles Darwin ShipShip: H.M.S. Beagle: H.M.S. Beagle Destination:Destination: Voyage around the world. Voyage around the world. Findings:Findings: evidence to propose a evidence to propose a
revolutionary hypothesis about how life revolutionary hypothesis about how life changes over timechanges over time
The Galapagos Island
Darwin was fascinated in particular by the land Darwin was fascinated in particular by the land tortoises and marine iguanas in the Galápagos. tortoises and marine iguanas in the Galápagos.
Giant tortoises varied in predictable ways from Giant tortoises varied in predictable ways from one island to another.one island to another.
The shape of a tortoise's shell could be used to The shape of a tortoise's shell could be used to identify which island a particular tortoise identify which island a particular tortoise inhabited. inhabited.
Animals
The Journey Home
Darwin Observed that characteristics Darwin Observed that characteristics of many plants and animals vary of many plants and animals vary greatly among the islandsgreatly among the islands
Hypothesis:Hypothesis: Separate species may Separate species may have arisen from an original ancestorhave arisen from an original ancestor
Evolution as a Theory AND Fact
• Confusion sometimes arises as to whether Evolution Confusion sometimes arises as to whether Evolution is a theory or a fact. Actually it is both!is a theory or a fact. Actually it is both!
• The theory of Evolution deals with howThe theory of Evolution deals with how
Evolution happens. Our understanding of this Evolution happens. Our understanding of this process is always changing. process is always changing.
• Evolution is also a fact as there is a huge amount of Evolution is also a fact as there is a huge amount of indisputable evidence for its occurrence. indisputable evidence for its occurrence.
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A brief history of evolution
Contrary to popular belief, Darwin was not the first person to describe the concept of evolution, but he was the one who gave it its driving force.
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Darwin presumed that populations of individuals changed over time, and, in 1844, he developed the concept of the driving force for evolution. It wasn’t until many years later that he published his idea.
“I have called this principle, by whicheach slight variation, if useful, is preserved, by the term Natural Selection.”
—Charles Darwin from "The Origin of Species“, 1859
Ideas that shaped Darwin’s Thinking James Hutton:James Hutton: 1795 Theory of 1795 Theory of
Geological changeGeological change Forces change Forces change
earth’s surface earth’s surface shapeshape
Changes are slowChanges are slow Earth much older Earth much older
than thousands of than thousands of yearsyears
Ideas that Shaped Darwin’s Thinking Charles LyellCharles Lyell Book: Book: Principles of Principles of
GeographyGeography Geographical features Geographical features
can be built up or torn can be built up or torn downdown
Darwin thought if Darwin thought if earth changed over earth changed over time, what about life?time, what about life?
Lamarck
Lamarck’s Theory of Evolution
Tendency toward PerfectionTendency toward Perfection Giraffe necksGiraffe necks
Use and Disuse Use and Disuse bird’s using forearmsbird’s using forearms
Inheritance of Acquired TraitsInheritance of Acquired Traits
Lamarck’s Ideas
• Around 1800, scientists began to wonder whether Around 1800, scientists began to wonder whether species could change or species could change or transmutetransmute..
• Lamarck thought that if an animal acquired a Lamarck thought that if an animal acquired a characteristic during its lifetime, it could pass it characteristic during its lifetime, it could pass it onto its offspring. onto its offspring.
• Hence giraffes got their long necks through Hence giraffes got their long necks through generations of straining to reach high branches.generations of straining to reach high branches.
Population Growth Thomas MalthusThomas Malthus--
19th century English 19th century English economisteconomist
If population grew If population grew (more Babies born (more Babies born than die)than die) Insufficient living Insufficient living
spacespace Food runs outFood runs out Darwin applied this Darwin applied this
theory to animalstheory to animals
Controversy!
• Despite the achievement of scientific consensus on evolution, some religious groups continued to oppose the concept.
• In 1925, the teaching of evolution was outlawed in Tennessee, USA, resulting in the infamous Scopes Monkey Trial
Outside the Scopes Trial
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Basic premises for this discussion
Evolution is not a belief system. It is a Evolution is not a belief system. It is a scientific concept. scientific concept.
Evolution is a theory…but you don’t get Evolution is a theory…but you don’t get any better than that in scienceany better than that in science
There is a lot of contention about evolution, There is a lot of contention about evolution, but not among scientists or scientific but not among scientists or scientific organizations.organizations.
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Some basic definitions
Fact: an observation that has been Fact: an observation that has been repeatedly confirmedrepeatedly confirmed
Law: a descriptive generalization about how Law: a descriptive generalization about how the physical world behavesthe physical world behaves
Hypothesis: a testable statement that can be Hypothesis: a testable statement that can be used to build inferences and explanationsused to build inferences and explanations
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Some basic definitions
Theory: a well-substantiated explanation Theory: a well-substantiated explanation that incorporates facts, laws, inferences that incorporates facts, laws, inferences and tested hypotheses.and tested hypotheses.
In science, you don’t get any better than a theory.
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Natural Selection
Observation 1: Organisms generally have more offspring than can survive to adulthood.
Observation 2: Offspring are not identical. There is variation in their appearance, size, and other characteristics.
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Natural Selection
Inference: Those organisms that are better adapted to their environment have a greater likelihood of surviving to adulthood and passing these characteristics on to their offspring.
Survival of the “fittest.”
Natural Variation & Artificial Selection Natural variationNatural variation--differences among --differences among
individuals of a speciesindividuals of a species
Artificial selectionArtificial selection- nature provides the - nature provides the variation among different organisms, and variation among different organisms, and humans select those variations they find humans select those variations they find
usefuluseful..
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Observation and Inference
Let’s do a little exercise…
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Dinosaur tracks are common occurrences in the southern and eastern U.S.
Here is a section of tracks that were recently uncovered. Can you answer the following questions?
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•What is the size and nature of the organisms?
•Were the tracks made at the same time?
•How many animals were involved?
•Can you reconstruct the events that occurred?
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•In what direction did the animals move?
•Did they change speed or direction?
•Was the soil moist or dry?
•In what type of rock were the prints made?
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The following summer some more digging revealed more of the track. What additional information have you gained that allows you to refine your answers?
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•Were the tracks made at the same time?
•How many animals were involved?
•Can you reconstruct the events that occurred?
•In what direction did the animals move?
•Did they change speed or direction?
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In the final summer of the excavation one last part of the footprint trail was uncovered. Does this section provide additional information to refine your hypothesis?
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So what happened?
What part of your hypothesis is observation?
What part is inference?
What part is guess?
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This is how science is done.
Evolution by Natural Selection
The Struggle for ExistenceThe Struggle for Existence-members of -members of each species have to compete for food, each species have to compete for food, shelter, other life necessitiesshelter, other life necessities
Survival of the FittestSurvival of the Fittest-Some individuals -Some individuals better suited for the environmentbetter suited for the environment
Struggle For Existence & Survival of The Fittest
Descent
Descent with ModificationDescent with Modification-Each living organism has -Each living organism has descended, with changes from other species over timedescended, with changes from other species over time
Common DescentCommon Descent- were derived from common ancestors- were derived from common ancestors
Evidence of Evolution
The Fossil RecordThe Fossil Record
Geographic Distribution of Living ThingsGeographic Distribution of Living Things
Homologous Body StructuresHomologous Body Structures
Similarities in Early DevelopmentSimilarities in Early Development
Evidence for Evolution
The Fossil RecordThe Fossil Record--Layer show changeLayer show change
Geographic Geographic Distribution of Living Distribution of Living ThingsThings
Homologous Body Homologous Body StructuresStructures
Similarities in Early Similarities in Early DevelopmentDevelopment
Evidence of Evolution The Fossil RecordThe Fossil Record Geographic Geographic
Distribution of Distribution of Living Things-Living Things-similar similar environments have environments have similar types of similar types of organismsorganisms
Homologous Body Homologous Body StructuresStructures
Similarities in Early Similarities in Early DevelopmentDevelopment
Homologous Structures
Homologous StructuresHomologous Structures-structures that -structures that have different mature forms in different have different mature forms in different organisms, but develop from the same organisms, but develop from the same embryonic tissueembryonic tissue
Analogous Structures
Analogous StructuresAnalogous Structures-structures that -structures that have similar mature forms in different have similar mature forms in different organisms, but develop from different organisms, but develop from different embryonic tissueembryonic tissue
Similarities in Early Development
Evidence for Evolution
Vestigial organsVestigial organs-organs that serve -organs that serve no useful function in an organismno useful function in an organism
i.e. appendix, miniature legs, armsi.e. appendix, miniature legs, arms
Summary of Darwin’s Theory
Individuals in nature differ from one anotherIndividuals in nature differ from one another
Organisms in nature produce more offspring than can Organisms in nature produce more offspring than can survive, and many of those who do not survive do not survive, and many of those who do not survive do not reproduce.reproduce.
Because more organisms are produced than can survive, each Because more organisms are produced than can survive, each species must struggle for resourcesspecies must struggle for resources
Each organism is unique, each has advantages and Each organism is unique, each has advantages and disadvantages in the struggle for existencedisadvantages in the struggle for existence
Summary (cont.)
Individuals best suited for the environment survive and Individuals best suited for the environment survive and reproduce most successfullyreproduce most successfully
Species change over timeSpecies change over time
Species alive today descended with modification from Species alive today descended with modification from species that lived in the pastspecies that lived in the past
All organisms on earth are united into a single family tree All organisms on earth are united into a single family tree of life by common descentof life by common descent
The Tree of Life
• All living things share a common ancestor. All living things share a common ancestor.
• We can draw a Tree of Life to show how We can draw a Tree of Life to show how every species is related.every species is related.
• Evolution is the process by which one species Evolution is the process by which one species gives rise to another and the Tree of Life gives rise to another and the Tree of Life grows and branchesgrows and branches
So HOW does it all happen?
There are a series of mechanisms that make There are a series of mechanisms that make evolution happen in any living thingevolution happen in any living thing
Mechanism (1): All in the Genes
commons.wikimedia.org/wiki/Image:DNA_double_helix_vertikal.PNG
• The genetic make-up of an organism is known as its genotype.
• An organism’s genotype and the environment in which it lives determines its total characteristic traits i.e. its phenotype.
PhenotypeGenotype
Mechanism (2): DNA
Watson and Crick and their model of DNA
www.chem.ucsb.edu/~kalju/chem110L/public/tutorial/images/WatsonCrick.jpgen.wikipedia.org/wiki/DNA
DNA replication
• The double-helix structure of DNA was discovered in 1953.
• This showed how genetic information is transferred from one cell to another almost without error.
Mechanism (3): Mutation
upload.wikimedia.org/wikipedia/commons/7/79/Types-of-mutation.png humansystemstherapeutics.com/bb.htm
Types of mutation
Mutant fruitfly
• However, occasional mutations or copying errors can and do occur when DNA is replicated.
• Mutations may be caused by radiation, viruses, or carcinogens.
• Mutations are rare and often have damaging effects. Consequently organisms have special enzymes whose job it is to repair faulty DNA.
Mechanism (4): Variation
majorityrights.com/index.php/weblog/comments/racial_variation_in_some_parts_of_the_skull_involved_in_chewing/
• Nevertheless, some mutations will persist and increase genetic variation within a population.
• Variants of a particular gene are known as alleles. For example, the one of the genes for hair color comprises brown/blonde alleles.
Mechanism (5): Natural Selection
en.wikipedia.org/wiki/Image:Mutation_and_selection_diagram.svgen.wikipedia.org/wiki/Image:Mutation_and_selection_diagram.svg
• Mutant alleles spread through a population by sexual reproduction.
• If an allele exerts a harmful effect, it will reduce the ability of the individual to reproduce and the allele will probably be removed from the population.
• In contrast, mutants with favorable effects are preferentially passed on
Selection of dark gene
Mechanism (6): Peppered Moth
http://en.wikipedia.org/wiki/Image:Biston.betularia.7200.jpgen.wikipedia.org/wiki/Image:Biston.betularia.f.carbonaria.7209.jpgen.wikipedia.org/wiki/J._B._S._Haldane
• The Peppered Moth is an example of Natural Selection in action discovered by Haldane
• During the Industrial Revolution the trees on which the moth rested became soot-covered.
Haldane and the peppered moth
• This selected against the allele for pale color in the population (which were poorly camouflaged from predators) and selected for the dark color allele.
Mechanism (7): Microevolution
www.puppy-training-solutions.com/image-files/dog-breed-information.jpg
• The dog is another example of how selection can change the frequency of alleles in a population.
• Dogs have been artificially selected for certain characteristics for many years, and different breeds have different alleles. • All breeds of dog belong to the same species, Canis lupus (the wolf) so this is an example of Microevolution as no new species has resulted.
Dogs are wolves
Mechanism (8): Macroevolution
www.ingala.gov.ec/galapagosislands/images/stories/ingala_images/galapagos_take_a_tour/small_pics/galapagos_map_2.jpg
Galapagos finches
• However, if two populations of a species become isolated from one another for tens of thousands of years, genetic difference may become marked.
• If the two populations can no-longer interbreed, new species are born. This is called Macroevolution.
• Darwin’s Galapagos finches are an example of this process in action.
Mechanism (9): Speciation Today?
en.wikipedia.org/wiki/Image:Gb-lu-Angel-southbound.jpgen.wikipedia.org/wiki/Culex
London Underground Mosquito
• The mosquito was introduced to the London Underground during its construction around 1900.
• It became infamous in the War for attacking people sheltering from the Blitz.
• Studies indicate several genetic differences from its above-ground ancestors. Interbreeding between populations is difficult suggesting that speciation may be occurring.
Primordial Soup Hypothesized that organic molecules could form in Hypothesized that organic molecules could form in
the right conditions using electricity and inorganic the right conditions using electricity and inorganic moleculesmolecules
Once organic molecules existed, proteins could be Once organic molecules existed, proteins could be mademade
Proteins come from specific orders of DNAProteins come from specific orders of DNA
Membranes protected the DNA and a cell formedMembranes protected the DNA and a cell formed
Cellular Evolution
Prokaryotes first: smaller, simpler cells that Prokaryotes first: smaller, simpler cells that can live in harsh environmentscan live in harsh environments
Photosynthesis became a process to make Photosynthesis became a process to make food once oxygen was found in the food once oxygen was found in the atmosphere from stromatolitesatmosphere from stromatolites
Endosymbiont
This theory is based on the idea that small, This theory is based on the idea that small, prokaryotic cells were swallowed into larger cells prokaryotic cells were swallowed into larger cells and became part of their host cell. and became part of their host cell.
The smaller cells evolved into organellesThe smaller cells evolved into organelles
Chloroplasts and mitochondria have their own Chloroplasts and mitochondria have their own DNA and protein synthesis process separate from DNA and protein synthesis process separate from the rest of the cell in mitosisthe rest of the cell in mitosis
PRIMATE EVOLUTIONHumans appeared late in Earth’s history.
Primates are mammals with flexible hands and feet, Primates are mammals with flexible hands and feet, forward-looking eyes and enlarged brains.forward-looking eyes and enlarged brains.
Humans share a common ancestor with other primates.
– Prosimians are the oldest living primates.– They are mostly small and nocturnal.
Primates evolved into prosimians and anthropoids.
First primates were arboreal – associated features that we’ve inherited.First primates were arboreal – associated features that we’ve inherited.
PRIMATE CHARACTERISTICS
Topic 14 – Human Evolution
Prosimians – Lorises and Lemurs
Topic 14 – Human Evolution
10 cm
Prosimians: Tarsiers
They are subdivided into the New World monkeys, They are subdivided into the New World monkeys, Old World monkeys, and hominoids.Old World monkeys, and hominoids.
– Homonoids are divided into hominids, great apes, and lesser apes.
– Hominids include living and extinct humans.
– foraging– carrying infants and food– using tools
• Walking upright hasimportant adaptiveadvantages.
Bipedal means walking on two legs.
Most hominids are either the genus Most hominids are either the genus AustralopithecusAustralopithecus or or Homo.Homo.
Australopithecines were a successful genus.Australopithecines were a successful genus. TheThe Homo Homo genus first evolved 2.4 million years ago. genus first evolved 2.4 million years ago.
Homo sapiensHomo sapiens fossils date to 200,000 years ago. fossils date to 200,000 years ago. Human evolution is influenced by a tool-based culture.Human evolution is influenced by a tool-based culture. There is a trend toward increased brain size in hominids.There is a trend toward increased brain size in hominids.
Australopithecusafarensis
Homo habilis Homo neanderthalensis
Homo sapiens
Topic 14 – Human EvolutionPrimate Tree of Life
Our Closest Primate RelativesOur Closest Primate Relatives
Topic 14 – Human Evolution
†Homo habilis (Handy Man) †Homo rudolfensis (Rudolf Man) †Homo ergaster (Working Man) †Homo erectus (Upright Man) †Homo floresiensis (Flores Man — discovered 2003) †Homo antecessor (Predecessor Man) †Homo heidelbergensis (Heidelberg Man) †Homo neanderthalensis (Neanderthal Man) †Homo rhodesiensis (Rhodesia Man) †Homo cepranensis (Ceprano Man) †Homo georgicus (Georgia Man) †Homo sapiens idaltu (elderly wise man — discovered 1997)
Types of ‘Humans’
Topic 14 – Human Evolution
-bipedal-much less hair-reduced sexual dimorphism-larger brain-shorter jaw, snout-speech-symbolic thought (not unique)-complex tools-habitat: variable-diet: variable
Characteristics of Humans
Changes in PostureChanges in Posture
Topic 14 – Human Evolution
Opening in skull reveals
upright posture
How the shape of the skull changedHow the shape of the skull changed
Topic 14 – Human Evolution
Two theories:
1) Multiregional hypothesis (multiple origins)2) Replacement hypothesis
(single origin)
“mongoloid”
“negroid”
“caucasoid”
Homo erectus
H. sapiens skull is very distinctive
Topic 14 – Human Evolution
Two theories:
1) Multiregional hypothesis (multiple origins)2) Replacement hypothesis
(single origin)
Homo erectus (1.6 Ma-200 Ka)
H. sapiens fossil record
Europe: H. heidelbergensis & H. neanderthalensis (400-40 Ka)
H. sapiens (195 Ka): E Africa
H. sapiens (50 Ka): Asia, Europe
H. sapiens (40 Ka): Australia
H. sapiens (15 Ka): America
Geographical Changes
Topic 14 – Human Evolution
“mongoloid”
“negroid”
“caucasoid”
Europe: H. heidelbergensis & H. neanderthalensis (400-40 Ka)
Modern Day Skull Shapes
Chapter 17Organizing Life’s Diversity
ClassificationClassificationClassification: The grouping of objects or information based on similaritiesTaxononmy: The branch of biology that groups and names organisms based on studies of their different characteristics.
Aristotle’s System
Greek Philosopher, 384 -322 B.C.Developed the first widely accepted system.Developed the first widely accepted system.Two groupsTwo groups PlantsPlants
Divided into three groupsDivided into three groups• Herbs, shrubs, treesHerbs, shrubs, trees
Animals, grouped them according to where they lived.Animals, grouped them according to where they lived. Land, in air, or in water.Land, in air, or in water.
Many centuries passed before a new system Many centuries passed before a new system was used.was used.
Carolus Linnaeus’s System
Swedish Botanist, 1707-1778
Linnaeus’s system was based on physical and Linnaeus’s system was based on physical and structural similarities of organisms.structural similarities of organisms.
This form of classification is the basis of the This form of classification is the basis of the modern classification systemmodern classification system
Two names for a species
Linnaeus developed itBinomial nomenclature, two word naming.Binomial nomenclature, two word naming. First word identifies the genus of the organismFirst word identifies the genus of the organism
Genus; group of similar speciesGenus; group of similar species Second word often describes a characteristic of the Second word often describes a characteristic of the
organism.organism.• Example: Example: Homo sapiensHomo sapiens
The Latin language is used to name an organismThe Latin language is used to name an organismNo longer used in conversation, so it doesn’t change No longer used in conversation, so it doesn’t change
meaning.meaning.It is universal throughout the world.It is universal throughout the world.
BIOLOGICAL CLASSIFICATIONTaxonomist: identifies the underlying natural Taxonomist: identifies the underlying natural
relationships of organisms and use the information as a basis relationships of organisms and use the information as a basis for classification.for classification.
They compare the external and internal structure of an organism.They compare the external and internal structure of an organism. The organism’s geographical distribution and chemical makeup may help in The organism’s geographical distribution and chemical makeup may help in
revealing the probable evolutionary relationships.revealing the probable evolutionary relationships.
Taxonomy is a framework to find organisms that are Taxonomy is a framework to find organisms that are relatedrelated
Ex. Are dinosaur’s more related to reptiles or birds?Ex. Are dinosaur’s more related to reptiles or birds?
Taxonomy is a useful toolTaxonomy is a useful tool Poison control: figure if plant or animal are poisonous.Poison control: figure if plant or animal are poisonous.
Taxonomy is good for the economy.Taxonomy is good for the economy.
HOW LIVING THINGS ARE CLASSIFIED
ORGANISMS ARE RANKED IN ARBITRARY ORGANISMS ARE RANKED IN ARBITRARY TAXA THAT RANGE FROM HAVING VERY BROAD TAXA THAT RANGE FROM HAVING VERY BROAD CHARACTERISTICS TO VERY SPECIFIC CHARACTERISTICS TO VERY SPECIFIC CHARACTERISTICS.CHARACTERISTICS.
Kingdom; very broad characteristicsKingdom; very broad characteristics Example: animal kingdom, butterfly and an elephantExample: animal kingdom, butterfly and an elephant
PhylumPhylum Class Class OrderOrder FamilyFamily GenusGenus Species: very specificSpecies: very specific
Example: Example: sapienssapiens Genus species make up the scientific name. Genus species make up the scientific name.
Figure 17.5Page 459
Section 17.2The SIX KINGDOMS
How are evolutionary relationships determined?
Structural similaritiesStructural similaritiesBreeding behaviorBreeding behaviorGeographical distributionGeographical distributionChromosome comparisonsChromosome comparisonsBiochemistryBiochemistry
PHYLOGENETIC CLASSIFICATIONModels
Phylogeny: the evolutionary history of a Phylogeny: the evolutionary history of a speciesspeciesPhylogenetic classification uses the Phylogenetic classification uses the
evolutionary history of a species to reveal the evolutionary history of a species to reveal the evolutionary relationships of species.evolutionary relationships of species.
Example: cladistics, assume that groups of Example: cladistics, assume that groups of organisms diverge and evolve from a common organisms diverge and evolve from a common ancestral group.ancestral group.
THE SIX KINGDOMS
Used to be two, the three, the five, now sixProkaryotes: broken into two new kingdomsProkaryotes: broken into two new kingdoms 1. Archaebacteria1. Archaebacteria 2. Eubacteria2. Eubacteria
ProtistsProtistsFungiFungiPlantPlantAnimalsAnimals
PROKARYOTESArchaebacteria and Eubacteria
ArchaebacteriaArchaebacteria Found in extreme environments such as swamps, Found in extreme environments such as swamps,
deep ocean hydrothermal vents etc..deep ocean hydrothermal vents etc.. Only a few hundred speciesOnly a few hundred species
EubacteriaEubacteria More than 10,000 different typesMore than 10,000 different types Very strong bacteriaVery strong bacteria Less complex than ArchaebacteriaLess complex than Archaebacteria
ProtistsA very diverse group
A protist is a eukaryote type cellA protist is a eukaryote type cellLacks complex organ systemLacks complex organ systemLives in moist environmentsLives in moist environmentsSome are unicellular some are multicellularSome are unicellular some are multicellularSome are more plantlike some are more animal Some are more plantlike some are more animal
like like and some are fungi like.and some are fungi like.
FUNGI
HeterotrophsHeterotrophsDo not move from place to placeDo not move from place to placeEither unicellular or multicellularEither unicellular or multicellularMore than 100,000 known species of fungiMore than 100,000 known species of fungi
PlantsMulticellular oxygen producers
All are multicellular with cell wallsAll are multicellular with cell wallsAll photosynthesize, AutotrophsAll photosynthesize, AutotrophsPlant cells usually contain chloroplast, roots Plant cells usually contain chloroplast, roots
cells do not. cells do not. Plant cells are organized into tissue,Plant cells are organized into tissue,
Tissue is organized into organs that are organized into systems.Tissue is organized into organs that are organized into systems.
More than 500,000 known different plant More than 500,000 known different plant species.species.
ANIMALS
Multicellular consumersHeterotrophsHeterotrophsNearly all are able to move from place to place.Nearly all are able to move from place to place.Do not have cell wallsDo not have cell wallsVery organizedVery organized
Cells, tissue, organs, systems.Cells, tissue, organs, systems.