Evolution)*Exam*1 *Chapter*2*• Theories(of(Creation(o Theory*of*special*creation* Species*do*not*change*over*time* They*were*created*independently*of*one*another** They*were*created*recently*o Theory*of*Descent*with*modification* Species*are*not*im mutable,*bu t *change*ove r*t ime* Species*are*derived*not*independently,*but*from*a*common,*or*shared*ancestor*• 2.1(Evidence(of(Change(through(Time(*o Evidence*disproving*the*immutability*of*organisms** Evidence*from*living*species*o Microevolution)*small*sc a le*c h a n g e s*in *monitorin g*n a t u ra l*p o p u la tio n s *o Macroevolution)*by*exa mining*bod ie s *o f*livin g *o r g an is ms;*can*view*dramatic*change*• Direct*observation*o Soapberry*bugs)*data*sugg e s ts *th a t*t h e *so a p b e r ry *b u g*population s *evolved*due*to*their*new*host*;*evidence'of'microevolution'* the*two*sets*of*bugs*w ere *gene tically*differe nt*and *there fore *the*short*beaked*bu gs*ha ve*de scen ded *w ith*m od ification *from*the*long *be ake d *an ces tors*o Data*documents*the*reduction*in*beak*length*that*followed*the*introduct io n *of *th e*f lat *p odded*golden*rain*tree* Characteristics*of*soapberry*bugs*are*not*immutable;*they*have*changed*over*time*due*to*their*environment**• Vestigial*Organs*o A*vestigial*structure*is*a*useless*or*rudimentary*version*of*a*body*part*that*has*an*importan t*func tion*in*other,*closely*allied*species* Ex.*A*north*island*brown*kiwi,*a*flightless*bird,*has*tiny*stubby*wings* Ex.2*a*rubber*boa*has*remnant*hind*limbs*• The*interpretation*is*these*species*have*descended*with*modification* Humans*too*have*vestigial*structures* *• i.e*a*tailbon e*a n d *g oo s eb u mps*and*th e *p ro d u ct io n *of *CMAH* Evidence*from*the*fossil*record*o A*fossil*is*a*trace*of*any*organism*that*lived*in*the*past*o The*total*worldwide*collection*of*fossils*is*considered*the*fossil*record*• Fact*of*Extinction*o The*fact*that*many*species*have*gone*extinct*suggests*that*Earth’s*flora*and*faun a*h ave *ch an ge d*o ve r*tim e*• Law*of*Succession*o The*resemblance*between*living*and*fossil*forms*in*the*same*region*suggests*that*living*organisms*are*descended*with*modification*from*earlier*species* Todays*species*are*descended*with*modification*from*ancestors*that*lived*in*the*same*region;*it*is*to*be*expected*that*they*would*bea r*a*stron ger*rese m blan ce*to*th eir*recen t*ancestors*than*to*their*more*distantly*related*kin*in*other*parts*of*the*world**• Transitional*Forms*o Shows*a*mix*of*features*between*extinct*animals*and*present*day*ones*;*evidence'for'macroevolution*• 2.2(Evidence(of(Common(Ancestry*o Species*are*not*independent*but*are*connected*by*descent*from*a*shared*ancestor* An*introduction*to*Tree*Thinking*• Evolutionary*tree*o Phylogenetic*trees*are*a*visual*representation*of*descent*with*modification*from*a*common*ancestor*o The*groups*that*share*a*closer*common*ancestor*are*more*closely*related*than*they*a re*to*o thers * The*inventor*of*evolutionary*trees*was*Charles*Darwin*o Ring*Species)*one*species*can *s p lit *in to *2 * Freely*interbreeding*populations*connect*the*entire*species,*but*members*of*certain*populations*do*not*interbreed**o Homology* The*study*of*“likeness”*• Structural*and*Developmental*Homology*o Homologous)*structures*th a t*a re *u s e d *fo r*d if fe re n t*f u n ct io n s*b u t *h a ve *the*same*sequen ce*an d*arran ge m ent*o f*bon es* Developmental*homologies)*embr yo s *fr o m *d if fe re n t*vertebrates*show*striking*similarities*early*in*development** Molecular*Homology)*all*organisms *in h er ite d *th eir*gen etic*code*from*a*common*ancestor**• Processed*psudogenes*o Small*coding*bits*are*exons*separated*by*noncoding*intervening*sequences,*introns.*o Introns*ge t*s p lice d *o u t*a fte r*b e in g *transcribed*and*befo re*trans lation*into *mRNA*o Retrotransposons)*reverse*transcription*to*DNA*and*insertion*at*a*new*site* Processed*psuedogenes)*have*no*function*but*a ccu m u late *mutations;*the*older*one*is*the*more*mutations*it*will*have**o The'earlier'the'ancestor'in'which'a'processed'pseudogene'appeared,'the'more'descendent'species'will'have'inherited'it.'' This'is'consistent'with'data'p.58(Humans'and 'Prim a tes)'o Nonhomologus)*similarities*in*ligh t *o f*th e ir *fu n c tio n ;*i.e .*p o werful*tails*and*streamlined*bodies*of*a*shark*and*an*orca*whale**• Modern*concept*of*Homology*o Many*biologists*define*homology*as*similarity*due*to*the*inheritance*of*traits*from*a*common*ancestor*o Relationships*among*species* Species*that*are*extremely*similar*to*one*another*tend*to*be*clustered*geographically.*This*suggests*that*they*were*not*created*independently,*but*are*descen d e d *from*a*common*ancestor*that*lived*in*the*same*area*• Galapagos*Island)*a*population *e xp a n d e d *in *t h e*new*habit a t*a n d *th a t *subpopulations*subsequently*colonized*different*islands*in*the*group*o Once*mockingbird*populations*had*become*physically*isolated*from*one*another*in*this*way,*they*diverged*enough*to*become*distinct*species*o Evidence*of*Common*Ancestry*• 2.3(The(Age(of(Earth*o Uniformitarianism)*Hutton;*that *ge o lo g ic a l*p ro c e ss e s*t a kin g *p la c e*n o w*operate d *s im ila r ly*in *t h e *past* Proposed*in*oppo sit io n *to *c a ta s tro p hism**o Geologic*Time*Scale* Younger*rocks*were*deposited*on*top*of*older*rocks*(*Principle*of*superposition)* Lava*and*sedimentary*rocks*were*originally*laid*down*in*horizontal*postion*(Principle*of*original*horizontality)* Rocks*that*intrude*into*seams*in*other*rocks*are*you ng er*than *their*ho st*rock s*(princip le*of*cross*cutting*relationships)* Boulders*or*other*fragments*found*in*a*body*of*rock*are*older*than*their*host*rock*(principle*of*inclusio ns )* Earlier*fossil*forms*are*simpler*than*more*recent*forms,*and*more*recent*forms*are*most*similar*to *ex istin g *fo rms*(principle *o f*fa u n a l*su c ce ssio n )*o Radiometric*Dating* Uses*unstable*isotopes*of*naturally*occurring*elements.*Isotopes*decay,*meaning*that*they*change*into*either*d ifferen t*elem e nts*or*different*isotopes*of*the*same*element*• One*half*life*is*the*amount*of*time*it*takes*for*50%*of*the*parent*isotope*present*to*decay*into*its*daughter*isotope*• 2.4(Is(There(Necessarily(a(Conflict(between(Evolutionary(Biology(and(Religion?*o