fossil evidence fossils- any traces of dead organisms dinosaur bones dinosaur bones insects trapped...
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Fossil EvidenceFossil Evidence
Fossils-Fossils- a any traces of dead organismsny traces of dead organisms dinosaur bonesdinosaur bones insects trapped in tree sapinsects trapped in tree sap leaf impressionsleaf impressions footprintsfootprints
Fossil EvidenceFossil Evidence Transitional speciesTransitional species- - species that have been species that have been
found in the fossil record that are found in the fossil record that are intermediates between two other species in intermediates between two other species in the evolutionary process.the evolutionary process.
Radiometric datingRadiometric dating-- a dating technique that measures amount a dating technique that measures amount of radioactive material in a rock or fossil.of radioactive material in a rock or fossil.
Relative dating-Relative dating- a dating technique that estimates the date of a dating technique that estimates the date of a fossil by relating it to the age of the layers of rock around it.a fossil by relating it to the age of the layers of rock around it.
Fossil EvidenceFossil Evidence
To fossilize an organism To fossilize an organism must be buried by must be buried by sedimentsediment. .
In swamps, mud, tar pits, In swamps, mud, tar pits, or the ocean bottom.or the ocean bottom.
Hard stuff fossilizes Hard stuff fossilizes (bones, nails). (bones, nails).
Radiometric and relative Radiometric and relative dating are used to find out dating are used to find out how old the fossil is.how old the fossil is.
Relative Dating
RadiometricDating
Fossil EvidenceFossil Evidence Fossils show:Fossils show:
Life has been around for millions of yearsLife has been around for millions of years Transitional species link older to newer speciesTransitional species link older to newer species
Darwin proposed the idea of transitional species, Darwin proposed the idea of transitional species, though he had no evidencethough he had no evidence
Today we have evidence:Today we have evidence:• ArchaeopteryxArchaeopteryx• WhalesWhales
Fossil Evidence-ArchaeopteryxFossil Evidence-Archaeopteryx
BEAK
WINGS
Fossil EvidenceFossil Evidence
Whales--60 million years of evolutionWhales--60 million years of evolution Descended from 4-legged wolf-like Descended from 4-legged wolf-like
animals that were also ancestors to animals that were also ancestors to cows and horsescows and horses
Fossil evidence shows slow loss of legsFossil evidence shows slow loss of legs Pelvis still remains with no rear legsPelvis still remains with no rear legs
Fossil Evidence-WhalesFossil Evidence-Whales
Whale Video
Earth is estimated to be about 4.6 billion Earth is estimated to be about 4.6 billion years old.years old.
Atmosphere was harsh.Atmosphere was harsh. Very Hot.Very Hot. Lots of water vapor Lots of water vapor VolcanoesVolcanoes NO BREATHABLE OXYGEN GAS!NO BREATHABLE OXYGEN GAS! COCO22, ammonia, methane present, ammonia, methane present
Origin of LifeOrigin of Life Scientists had hard time Scientists had hard time
finding evidence of early finding evidence of early life.life.
45 years ago we found out 45 years ago we found out why….why….
Most ancient life was Most ancient life was microscopic=microfossils in microscopic=microfossils in stromatolites.stromatolites.
11stst organisms to evolve organisms to evolve were prokaryotes were prokaryotes
Oldest microfossilOldest microfossil3.5 3.5 billion years old billion years old
Cyanobacteria fossil about 1,000,000,000 (1 billion) years old found in stromatolites
Stromatolites
Origin of LifeOrigin of Life’’s Chemicalss Chemicals Miller-UreyMiller-Urey Hypothesis: Can organic Hypothesis: Can organic
compounds form in early compounds form in early Earth conditions?Earth conditions?
Experiment recreated Experiment recreated atmosphere of early Earthatmosphere of early Earth
Results: building blocks of Results: building blocks of life were formed. life were formed. Amino acids (proteins)Amino acids (proteins) Nucleotides (DNA, RNA)Nucleotides (DNA, RNA) LipidsLipids CarbohydratesCarbohydrates
Self AssemblySelf Assembly Some molecules can Some molecules can
spontaneously form into spontaneously form into droplets droplets
Solution with lipids and Solution with lipids and proteins will self assemble proteins will self assemble into a lipid bilayer like a cell into a lipid bilayer like a cell membranemembrane
First cell membrane and First cell membrane and beginning of prokaryotic life beginning of prokaryotic life took 1 billion years.took 1 billion years.
What else is needed for life?What else is needed for life?
11stst genetic material- RNA genetic material- RNA
EarthEarth’’s early surface was inhospitable s early surface was inhospitable due to immense UV radiationdue to immense UV radiation
Deep sea vents may have provided Deep sea vents may have provided sheltered location for life. sheltered location for life.
Oldest living prokaryotes found there Oldest living prokaryotes found there today…today…
RNA can form under conditions similar RNA can form under conditions similar to deep sea ventsto deep sea vents
Road to Modern OrganismsRoad to Modern Organisms11stst life was bacteria life was bacteria unicellular prokaryotes unicellular prokaryotes
CyanobacteriaCyanobacteria- photosynthetic blue-green prokaryotes - photosynthetic blue-green prokaryotes later changed Earthlater changed Earth’’s atmospheres atmospherereleased Oreleased O22! !
22ndnd was unicellular eukaryotes was unicellular eukaryotes Endosymbiotic Endosymbiotic TheoryTheory
33rdrd was multicellular organisms was multicellular organisms
Classification/EvolutionClassification/Evolution6 Kingdoms6 Kingdoms
Classifying Living ThingsClassifying Living Things Carl Linnaeus was a Carl Linnaeus was a
scientist who developed a scientist who developed a classification system for classification system for living things.living things.
Wrote book Wrote book Systema Systema NaturaeNaturae in 1735 to in 1735 to reveal his classification reveal his classification system.system.
How biologists classifyHow biologists classify
1. 1. Comparing morphology Comparing morphology (physical traits)(physical traits)
2. Looking at genetic 2. Looking at genetic similarities & differencessimilarities & differences
3. Biochemical make-ups3. Biochemical make-ups 4. Behavioral similarities4. Behavioral similarities Origin of Life Video
CladogramsCladograms CladogramCladogram- a branching diagram that shows - a branching diagram that shows
evolutionary relationships. evolutionary relationships. We use We use taxonomytaxonomy – the science of classifying – the science of classifying
living things, to help us determine the living things, to help us determine the cladogram.cladogram.
Scientific NamingScientific Naming
Binomial nomenclature-Binomial nomenclature- unique 2-word unique 2-word naming system used by scientists.naming system used by scientists.
11stst word is the genus, 2 word is the genus, 2ndnd is the species. is the species. GenusGenus- group of organisms that share similar - group of organisms that share similar
characteristics.characteristics. Panthera leo-Panthera leo-lionlion Panthera pardus-leopardPanthera pardus-leopard
SpeciesSpecies- group of organisms that can - group of organisms that can successfully breed within their group, but not successfully breed within their group, but not others.others.
How to write a scientific How to write a scientific namename
Genus is always capitalizedGenus is always capitalized Species is always lower Species is always lower
casecase The whole name is The whole name is
underlined if written or underlined if written or italicized if typed.italicized if typed.
Example: Example: Homo sapiensHomo sapiens
ExamplesExamples Homo sapiensHomo sapiens::
HomoHomo = genus = genus sapienssapiens = species = species Common name = humansCommon name = humans
Quercus rubraQuercus rubra–– Quercus = Quercus = genusgenus rubra = rubra = speciesspecies Common name = red oakCommon name = red oak
Scientific names are in Latin b/c scholars in the Scientific names are in Latin b/c scholars in the Middle Ages communicated using it!Middle Ages communicated using it!
6 Kingdoms6 Kingdoms There are six kingdoms all living There are six kingdoms all living
things are classified into:things are classified into: AnimalsAnimals PlantsPlants FungiFungi ProtistsProtists EubacteriaEubacteria Archeabacteria Archeabacteria
ClassificationClassification Scientists have determined Scientists have determined
seven levels of classification: seven levels of classification: KingKingdom = dom = KKingingss PPhylum = hylum = PPassass ClassClass = = ClassClasseses OrderOrder = to = to OrderOrder FamilFamilyy = = FamilFamiliesies GGenus = and their enus = and their GGood ood SSpecies = pecies = SSons aroundons around
Classification of Modern Classification of Modern HumansHumans
Kingdom = AnimaliaKingdom = Animalia Phylum = ChordataPhylum = Chordata Class = MammaliaClass = Mammalia Order = Primates Order = Primates Family = HominidaeFamily = Hominidae Genus = Genus = HomoHomo Species = Species = sapienssapiens
Evolution of PrimatesEvolution of PrimatesPrimate-Primate- mammal with 5 flexible mammal with 5 flexible fingersfingers
Earliest dwelled in trees-Earliest dwelled in trees-arborealarboreal
Needed special adaptations for Needed special adaptations for this:this:– Opposable thumb….Why?Opposable thumb….Why?– Binocular vision-Binocular vision- eyes in front eyes in front
of head in which field of vision of head in which field of vision of eyes overlap—depth of eyes overlap—depth perception….Why?perception….Why?
– Rotating ShouldersRotating Shoulders
Evolution of HumansEvolution of HumansVocab:Vocab:– BipedalBipedal- walk upright on two legs- walk upright on two legs– HominidHominid- bipedal primates such as - bipedal primates such as
humans and their closest fossil relativeshumans and their closest fossil relatives
HominidsHominidsHominids are the ONLY bipedal primates:Hominids are the ONLY bipedal primates:– Locking knee jointsLocking knee joints– Spine enters skull atSpine enters skull at
bottom of headbottom of head– Femurs (thigh bone)Femurs (thigh bone)
tapers intapers in– Big toe in line with Big toe in line with
othersothersLaetoli Footprints
Hominid vs. chimpanzeeHominid vs. chimpanzee
Chimps most closely related primate to Chimps most closely related primate to humans—95% similarity in the sequence of humans—95% similarity in the sequence of our genes!our genes!
HumanHuman’’s jaw arc shaped with smaller s jaw arc shaped with smaller canines; chimpscanines; chimps’’ are U shaped with larger are U shaped with larger canines and larger gaps.canines and larger gaps.
Hominid vs. chimpanzeeHominid vs. chimpanzee
Hominid spine S– Hominid spine S– chimpschimps’’ is C shaped is C shaped
Hominid pelvis is Hominid pelvis is bowl-shaped, chimpsbowl-shaped, chimps’’ longlong
Hominid thigh bones Hominid thigh bones taper in—chimpstaper in—chimps’’ out out
Human Evolution Human Evolution Video ClipVideo Clip
Early HominidsEarly HominidsGenus Genus AustralopithecusAustralopithecus– LucyLucyAustralopithecus afarensisAustralopithecus afarensis– Fossil found in AfricaFossil found in Africa– They were hominidsThey were hominids
Shape of pelvis and femurs showed Shape of pelvis and femurs showed they were bipedal. they were bipedal.
Locking knee jointsLocking knee joints
– Short—3Short—3’’66’’’’– Brain size of chimpsBrain size of chimps– Jaws more rounded than apesJaws more rounded than apes– Teeth like humansTeeth like humans
LUCYLUCY3.5 million years old3.5 million years old
40% complete40% complete
FemaleFemale
Showed us:Showed us:– Walked upright firstWalked upright first– Brain size grew Brain size grew
LATER.LATER.
SKULLSSKULLS
A. afarensis (Lucy) Homo sapienA. afarensis (Lucy) Homo sapien
SKULLSSKULLS Lucy had a small skull like an ape, but she wasnLucy had a small skull like an ape, but she wasn’’t one.t one.
LUCY APELUCY APE
LUCY VS. APELUCY VS. APE
Homo habilisHomo habilisMeans: Handy manMeans: Handy man
Small structure like Small structure like LucyLucy
Skull 2XSkull 2X’’s the size s the size of Lucyof Lucy
2- 1.8 mya in Africa2- 1.8 mya in Africa
Tools made of bone Tools made of bone and stone. and stone.
Homo erectusHomo erectus
Peking manPeking manAfrica / Asia / EuropeAfrica / Asia / EuropeLarger than H. habilisLarger than H. habilisLarger brainLarger brainExcellent tools, used fireExcellent tools, used fire1.5 mya – 1.5 mya – ““immediateimmediate”” ancestorancestor
Where Did Where Did H. sapiensH. sapiens evolve? evolve?
Out of Africa Out of Africa hypthothesis-hypthothesis- idea idea like Darwinlike Darwin’’s which s which states states H. sapiensH. sapiens evolved IN Africa and evolved IN Africa and spread to rest of spread to rest of worldworld
Out of Africa Out of Africa hypothesis supported hypothesis supported by fossils of modern-by fossils of modern-like humans found in like humans found in AfricaAfrica
H..sapiens
H. erectus
Early Early H. sapiensH. sapiens
Homo neanderthalensis -Homo neanderthalensis -discovered in Neander Valley discovered in Neander Valley in Belgiumin Belgium
Massive skulls and Massive skulls and
protruding brows protruding brows
400,000-100,000 years ago400,000-100,000 years ago
Early Early H. sapiensH. sapiensGreat controversy: did Great controversy: did
they die off (genes no they die off (genes no longer) or did they longer) or did they interbreed with us so their interbreed with us so their genes are still in our gene genes are still in our gene pool?pool?
Modern Modern H. sapiensH. sapiens probably evolved in Africa probably evolved in Africa and replaced Neanderthals.and replaced Neanderthals.
APES Homo neanderthalensis Homo sapiens
Homo erectusHomo erectus
transitional speciestransitional species Homo habilis Homo habilis
Australopithecus Australopithecus afarensis afarensis
common ancestor tocommon ancestor to
ape andape and H. sapiens H. sapiens
Mated????Mated????