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LECTURE 1Chapter 14Professors Notes:

1) Trait variation is due to alternative version(alleles) of heritable fators(!enes)") for eah harater an or!anis# inherits " alleles$ one fro# eah parent%) &'N*NT alleles #as+ reessive alleles

4) " alleles for a heritable harater ,E-RE-*TE durin! !a#ete for#ation . end upin di/erent !a#etes 0 L*2 '3 ,E-RE-*T'NPUNNETT ,5URE 0 %:1 R*T'6e!innin! of hu#an !enetis he#ophelia 7as reo!ni8ed as hereditar9 ;

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one fro# its father? 7hen this or!anis# for#s its o7n !a#etes$ eah !a#ete 7illreeive onl9 one of these alleles$ and this proess is rando#

in the ase of " di/erent alleles at a partiular lous$ the or!anis#s phenot9pe 7illbe deter#ined b9 the do#inant allele$ 7hih is able to #as+ the e/ets of thereessive allele= n order for the reessive trait to be seen$ both alleles arried b9the or!anis# #ust be reessive

PUNNETT ,5U*URE 0 dia!ra# used to deter#ine the ratio of di/= phenot9pes and!enot9pes in o/sprin!$ resultin! fro# rossin! parents 7ith di/erent o#binationsof !enot9pes=

''K@-'U, 0 " ,*E *LLELE, at a partiular !ene ETER'K@-'U, 0 " &33ERENT *LLELE, at a partiular !ene PEN'T@PE: or!anis#s appearane$ or observable harateristis -EN'T@PE: o#plete !eneti #a+e up

Law of Independent Assortmentstates that alleles of di/erent !enes assort independentl9 of one another durin!!a#ete for#ation'N'@6R& CR',,0 #atin! bt7= individuals 7ho have di/= alleles at one !enetilous of interest&@6R& CR',,0 ross bt7= 31 o/sprin! of " individuals that di/er in " traits ofpartiular interest

EF) 6b F 6b 0 6(bro7n)$ b(blue)$ 66(dar+)$ 6b(6ro7n)$ bb(blue),etion "Probability rules and simple Mendelian geneticsP( and @) 0 P() F P(@)P( or @) 0 P() M P(@),etion %omplex inheritance patterns from a single geneo#plete do#inane ours 7hen the o/sprin! al7a9s has the sa#e phenot9pe asone or both of its parents= one of the possible alleles is al7a9s do#inant over theother and al7a9s ditates the phenot9pes

eF) 66(6ro7n) F bb(blue) 0 6b(6ro7n)no#plete do#inane ours 7hen the hetero89!ous individuals displa9 a di/erentphenot9pe than either the reessive or do#inant ho#o89!otes? neither of the allelesare o#pletel9 do#inant$ and the resultin! inter#ediate phenot9pe is usuall9 a blendof the t7o possible traits=

eF) CRCR(Red) F C6C6(6lue) 0 CRC6(purple)Codo#inane: ondition in 7hih both alleles of a !ene pair in a hetero89!ote arefull9 eFpressed$ 7ith neither one bein! do#inant or reessive to the other=

eF) **(T9pe *) F 66(T9pe 6) 0 *6(t9pe *6)PLETR'P@ 0 ours 7hen sin!le !enes #a9 a/et #ultiple phenot9pi haraters$suh as #ultis9#pto# diseases in hu#ans$ si+leell disease$ or 9sti Ibrosis,etion 4Tracing alleles through a family history

a pedi!ree is a dia!ra# sho7in! the anestral relationships and trans#ission of!eneti traits over several !enerations in a fa#il9

in pratial appliation$ pedi!rees an be used to predit the future ourrene of

heritable disorders eFa#inin! the pattern of the inheritane of a trait in a pedi!ree an help deter#ine

7hether it is bein! inherited as a do#inant or reessive trait

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6,C 1"< LECTURE N'TE "

Chapter 1;

endels hereditar9 fatorsD are loated on hro#oso#es

earl9 studies of #eiosis sho7ed that the behavior of hro#oso#es parallels the

behavior of endels fatorsD

6oth hro#oso#es and fatorsD

present in pairs in &PL'& ells

se!re!ate durin! #eiosis

halve their op9 nu#bers durin! #eiosis and double their op9 nu#bers at

fertili8ation

T'*, UNT 'R-*N, 3RUT 3L@ eFperi#ents provided the Irst stron! evidene

that !enes are on hro#oso#es

2@ 3RUT 3LE,O

eas9 to rear in lab

short !eneration ti#e(1

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e#ophilia

&uhenne #usular d9stroph9

Color 6lindness

Chapter 1S

2*T , TE -ENETC *TER*LO (PR'TEN 'R &N*O)

-R33T et al= sho7ed that an un+no7n substane ould TR*N,3'R(C*N-E TE

-EN'T@PE *N& PEN'T@PE) 6*CTER*

ER,E@ *N& C*,E used bateriopha!e(a +ind of virus) to deter#ine 7hat

substane the virus uses to repro!ra# baterial ells

3R*NLN and 2LN, #ade ra9 di/ration i#a!es of &N*

2*T,'N and CRC used the ra9 i#a!es to dedue the double heliF

1>;%: 2*T,'N *N& CRC RE,'LQE& %& ,TRUCTURE '3 &N*

,@NTE,KN- * 3UNCT'N*L -EN'E: a tea# led b9 =CR*- QENTER hassueeded in reatin! a s9ntheti baterial !eno#e and usin! it to ontrol a ell

&N* C'NT*N, % C'P'NENT,: NTR'-ENC'NT*NN- 6*,E$ * PENT',E

,U-*R(&E'@R6',E)$ *N& * P',P*TE -R'UP

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Leture %

&*R2N*N REQ'LUT'N

Top ; #9ths about C*RLE, &*R2N

M!T" #$&ar7in 7as the Irst to propose that life on this planet evolved

#an9 people proposed evolutionar9 ideas before &ar7in$ and #an9 otherspaved the 7a9 for his theor9$ even if the9 did not believe in evolution

the#selvesEvolution ideas be!an 7G anient -ree+s

E#pedoles believed plants a#e Irst$ then ani#al&eveloped a theor9 of stru!!le a#on! ani#als that foreshado7s natural seletion

*R,T'TLE believed life for#s 7ere IFed$ but his ,ala Naturae inspiredevolutionar9 theoriesLNN*EU, developed a lassiIation s9ste# that pla9ed a role in &ar7insevolutionar9 ar!u#ents

did not believe in evolutionused lassiIation s9ste# to reveal the divine order of lifeonsidered the father of taFono#9

evolution 7as supported b9 the !eolo!i theor9 of -R*&U*L,$ but N'T b9C*T*,TR'P,

CUQER$ a hard ore CatastrophistPaleontolo!istfound di/= fossils in di/= strata and inferred eFtintionbelieved boundaries bt7= strata due to atastrophes

UTT'N and L@ELL advoated !radualis#believed earths features eFplained b9 proesses urrentl9 operatin!i#plied earth is S

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support$ and #an9 o/sprin! fail to survive or reprodue

*LTU, 6*,C TE'R@: unless at or belo7 subsistene level$ a populationsfertilit9 7ill tend to #ove=

M!T" %$

&ar7in 7ent to the -alapa!os$ studied the bea+s of Inhes$ and thus disoveredevolution&ar7in didnt +no7 #an9 of his sa#ples 7ere Inhes until an ornitholo!istI!ured it out

TE 'R-N '3 ,PECE,(1B;>);1% p!

; pa!es devoted to the -alapa!os 3inhes are never #entioned

evidene for adaptive radiation in Inhes a#e #uh laterinstead$ &ar7in based his theor9 on a 7ide diversit9 of !eolo!ial and biolo!ialobservations

M!T" &$&ar7ins 'n the 'ri!in of ,peiesD dou#ent nu#erous eFa#ples of naturalseletion in ation

&ar7in observed eFtensive *RT3C*L ,ELECT'N

ho7ever$ dou#entation of N*TUR*L ,ELECT'N in ation is #ore reent

M!T" '$Evolution is a theor9 about the ori!in of life

&ar7in did believe that all or!anis#s on Earth trae their ori!in to a sin!le anestorho7ever$ he 7as not at all lear on ho7 life itself ori!inated

M!T" ($&ar7in 7as an atheist bent on brin!in! do7n the Churh

&ar7ins reli!ious vie7s 7ere o#pliated and han!ed throu!hout his liferaised as a Christian and studied to beo#e a ler!9#anver9 uno#fortable 7G onJit bt7= his theor9 and biblial teahin!s$ and thisli+el9 dela9ed publiation of TE 'R-NeFperiened a loss of faith after the death of his >9ear old dau!hter *nniein later life he desribed hi#self as an *!nosti$ but never an *theist

Leture 4

Ch="" ,etion % Case 3or and *!ainst Evolution

*r!u#ent 1: Evolution annot be observed and therefore annot be proven

Rebuttal: evolution is observed all the ti#eV

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7e ant observe the ENTRET@ of evolution and therefore rel9 on diverse lines

of evidene$ Wust as 7e do in other Ields

*r!u#ent ": There are no transitional fossils

Rebuttal: The fossil reord is spott9$ but there *RE transitional for#s

i=e= transition bet7een Ish and tetrapods? transition bet7een reptile and birds?

transition bet7een horse speies? transition fro# land #a##als to 7hales?

transitional fossil JatIsh 7ith partiall9 #i!rated e9es

*r!u#ent %: Chane annot reate o#pleFit9

Rebuttal:utations are rando#? but seletion is N'T

*r!u#ent 4: the Irst step to7ard o#pleF adaptations ould not have been

favored(0irreduible o#pleFit9)

Rebuttal:nitial steps 7ill be favored if the9 o/er even a sli!ht advanta!e$ even

for an entirel9 di/erent purpose

*r!u#ent ;: Natural seletion violates the seond la7 of ther#od9na#is(entrop9

7ill inrease in an isolated s9ste#)

Rebuttal: The earth is not an isolated s9ste#

*r!u#ent S: Evolution is onl9 a theor9

Rebuttal: evolution is both a fat and an enor#ousl9 7ellsupported

theor9(TE'R@02ELL,U6,T*NT*TE& EPL*N*T'N '3 * ,ET '3

N*TUR*L PEN'EN* N ,CENCE)

3at speies han!e over ti#e

Theor9 speies han!e over ti#e due to the o#bined fores of #utation$

#i!ration$ !eneti drift and natural seletion

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)*idence for )*olution+

&iret observations of evolutionar9 han!e:

Chan!es in bea+ si8e in -alapa!os Inhes

Predationindued han!es in !upp9 oloration

ndustrial #elanis# in #oths

Evolution of resistane to antibaterial and antiviral dru!s

Evolution of pestiide resistane

Chan!es in soapberr9 bu! bea+ len!th

o#olo!ous haraters

,i#ilarities due to o##on anestr9

*nato#ial ho#olo!iesG oleular ho#olo!ies

i=e= a##alian foreli#bs: ho#olo!ous strutures 7ith ver9 di/erent funtions

Qesti!ial traits: historial re#nants of traits for anestors

'LECUL*R ''L'-@: -ENETC C'&E

3ossil reord

2h9 does it #atter if evolution is true or notO

Evolutionar9 thin+in! is ruial to a!riulture

'ne 7a9 to slo7 the evolution of pestiide resistane is to provide RE3U-*

Evolution thin+in! is ruial to #ediine

Tre#endous inrease in antibioti resistane had led to:

1) lon!er hospital sta9s

") hi!her treat#ent osts

1) "% fold hi!her #ortalit9 in hospitali8ed patients

6io#edial Ield tends to avoid the ter# evolutionD 7hen desribin! evolutionar9

proesses

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3iFin! the antibioti proble# 7ill reHuire !reater evolutionar9 a7areness fro#

dotors$ patients$ and far#ers=

Leture ;

Chapter "% ,etion 1"

Populations evolve$ individuals do not

ard92einber! Priniple an be used to test 7hether population is evolvin!

Population: loali8ed !roup of individuals of the sa#e speies that an

interbreed and produe fertile o/sprin!

Evolution: han!e in the !eneti o#position of a population fro# !eneration to

!eneration

!iven a series of assu#ptions$ allele freHuenies and !enot9pe freHuenies 7ill not

han!e bet7een !enerations

*ssu#ptions: N' ,ELECT'N

N' UT*T'N

N' -R*T'N

N3NTEL@ L*R-E P'PUL*T'N

R*N&' *TN-

if these assu#ptions are #et$ allele and !enot9pe freHuenies 7ill not han!e

bet7een !enerations

TERN'L'-@:

i#a!ine a population #ade of 1

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ultipliation rule: o#bined probabilit9 of independent events ourrin! to!ether is

the produt of their individual probabilities

*ddition rule: o#bined probabilit9 of " #utuall9 eFlusive events is the su# of their

individual probabilities

pMH 01? p"M"pHMH" 0 1

o7 to test 2:

test 7hether observed !enot9pe nu#bers #ath eFpeted !enot9pe

nu#bers(alulated fro# allele freHuenies)

2 for#s the basis of #iroevolutionar9 studies

it serves as a null #odel if a population does not onfor# to 2E 7e an loo+ at

7hih assu#ptions are violated(i=e= 7hih evolutionar9 fores are atin!)

pratial appliations in #ediine$ a!riulture$ forensis

Evolutionar9 proesses

utation and seFual reo#bination produe ne7 variation

,eletion$ drift$ and !ene Jo7 alter allele freHuenies in a population

utation

The ra7 #aterial of evolution

a t7o ed!ed s7ordD #ost #utations are deleterious but a fe7 are beneIial and

these provide the basis for evolutionar9 han!e

inds of #utations

1) Point #utation:

sin!lebase substitutions aused b9 &N* pol9#erase errors in either &N*

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s9nthesis or &N* repair

si+le ell ane#ia results fro# a sin!le point #utation

1) nsertionsG&eletion(ndels):

ndels an ause addition or loss of a#ino aids$ fra#eshifts$ or trunated

proteins

1) -ene dupliations

&upliation of a short streth of &N*

Caused b9 uneHual rossovers durin! #eiosis$ or strand slippa!e durin! &N*

repliation

&upliates #a9 either #aintain funtion$ !ain a ne7 funtion$ or lose

funtion(pseudo!enes)

-ene dupliation has !iven rise to variet9 of !ene fa#iliesD

!ene fa#ilies are sets of !enes that have si#ilar &N* seHuene but var9 in

o#position and funtions

i=e= or!anis#s fro# bateria to hu#ans harbor a diverse fa#il9 of heat sho+

proteins involved in foldin! and unfoldin! proteins$ transportin! proteins aross

#e#branes and !eneral stress response

1) Chro#oso#e inversions (results in ne7 !ene order: *6C&E3 *6E&C3

") Pol9ploidi8ation

pol9ploid or!anis#s have #ore than " sets of hro#oso#es

pol9ploid9 usuall9 ours bG of a failure in redution division at #eiosis 7hih

results in a "n !a#ete=

Pol9ploid9 an ause instant speiation

7hen a #utant "n !a#ete fuses 7ith a nor#al 1n !a#ete$ the resultant %n

o/sprin! is t9piall9 sterile due to proble#s at #eiosis

if the #utant "n !a#ete is lu+9 enou!h to fuse 7ith another #utant "n

!a#ete the resultant 4n o/sprin! is instantl9 reprodutivel9 isolated

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,in!le #utations rarel9 produe si!niIant adaptive han!e= ost #utations are

neutral or deleterious

,eF reshuXes the !ene pool

1) rando# assort#ent of hro#oso#es

7ith "% pairs of hro#oso#es hu#ans an produe B #illion o#binations of

intat hro#oso#es

1) Crossin! over 7ithin hro#oso#es

2ith rossin! over$ a sin!le hu#an ouple is theoretiall9 apable of produin!

#ore a nu#ber of o#binations !reater than the total nu#ber of people that

have ever lived

1) 3ertili8ation

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Leture S

Chapter "% ,e= %4

Natural ,eletion

di/erential survival andGor reprodution results in ertain alleles bein! passed to the

neFt !eneration in !reater proportions

Rando# -eneti &rift

han!es in allele freHuenies 7ithin populations 7hih result fro# hane variation

in individual survival and reprodution

#ost i#portant in s#all population

an result in #aladaptive evolution

,a#plin! Error alters allele freHuenies in Inite population

fro# ;

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-ene Jo7

onsists of !eneti additions or subtrations fro# a population$ resultin! fro#

#ove#ent of fertile individuals or !a#etes

auses a population to !ain or lose alleles

tends to redue di/erenes bet7een populations over ti#e

Natural seletion is the pri#ar9 #ehanis# of adaptive evolution

natural seletion au#ulates and #aintains favorable !enot9pes in a population

depends on eFistene of heritable$ !eneti variation

odes of ,eletion:

,tabili8in!

&iretional

&isruptive

,eFual:

natural seletion for #atin! suess

an result in seFual di#orphis#

seFuall9 seleted traits #a9 be bad for survival

Preservation of -eneti Qariation

various #ehanis#s help to preserve !eneti variation in a population

1) diploid9: #aintains !eneti variation in the for# of hidden reessive alleles

") balanin! seletion: ours 7hen natural seletion #aintains " or #ore for#s in

pop=

leads to a state alled balaned pol9#orphis#

hetero89!ote advanta!e is one for# of balanin! seletion

ne!ative freHuen9dependent seletion is another for# of balanin! seletion

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Natural seletion doesnt produe perfet or!anis#s

i=e=) hu#ans have fondness for fats$ su!ar$ alohol$ tobao$ sloth? poorl9

desi!ned +nees? ba+ proble#s? fra!ile e9es? helpless infants? useless appendiF

Leture Z

Chapter "4 ,e=1"

*re speies realO

speies are the funda#ental unit of or!ani8ation in nature

'rnitholo!ist Ernst a9r identiIed 1%Z birds in Papua Ne7 -uinea

Native Papuans alread9 had na#es for 1%S speies= There are about B=Z MG 1=%

#illion ,E

No sin!le speies onept an be applied in all situation

1) #orpholo!ial: deInes a speies b9 strutural features

") eolo!ial: vie7s a speies in ter#s of its eolo!ial nihe

%) ph9lo!eneti: deInes a speies as the s#allest !roup of individuals that share a

o##on anestor

4) biolo!ial: atuall9 or potentiall9 apable of interbreedin!

6iolo!ial speies onept is #ost popular$ but does not 7or+ in all situations

aseFual taFa

fossils

taFa not a#enable to breedin! studies

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No speies onept 7or+s in all situations

#an9 speies have fe7 distin!uishin! #orpholo!ial haraters

often have too little infor#ation to appl9 eolo!ial or ph9lo!eneti onepts

fossils rarel9 distin!uish taFa do7n to the speies level

T7o t9pes of reprodutive barriers

1) Pre89!oti barriers i#pede #atin! or hinder fertili8ation if #atin! does our:

*= habitat isolation(7ron! plae)

" speies enounter eah other rarel9$ or not at all$ bG the9 oup9 di/erent

habitats

i=e= #arine i!uanas vs= land i!uana

*= te#poral isolation(7ron! ti#e)

speies that breed at di/erent ti#es of the da9$ di/erent seasons$ or di/erent 9ears

annot #iF their !a#etes

i=e= 1% vs 1Z 9ear iadas

*= behavioral isolation(no attration)

ourtship rituals and other behaviors uniHue to a speies are e/etive barriers

i=e= La9san albatross ourtship

*= #ehanial isolation(ant opulateGpollinate)

#orpholo!ial di/erenes an prevent suessful #atin!

i=e= anthers not positioned to put pollen on a bee$ but 7ill put pollen on a bird

*= !a#eti isolation(ant fertili8e)

sper# of one speies #a9 not be able to fertili8e e!!s of another speies

i=e= #an9 broadast spa7nin! #arine invertebrates

1) Post89!oti barriers prevent h9brid 89!ote fro# developin! into a viable$ fertile

adult

*= Redued h9brid viabilit9

-enes of the di/erent parent speies #a9 interat and i#pair the h9brids

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develop#ent

i=e= Rana pipiens F Rana s9lvatia h9brids do not survive #ore than a da9

*= Redued h9brid fertilit9

even if h9brids are vi!orous$ the9 #a9 be sterile due to proble#s at #eiosis

i=e= Li!ers(#ales sterile)

*= 9brid brea+do7n

so#e Irst!eneration(31) h9brids are fertile$ but 7hen the9 #ate 7ith another 31

h9brid or 7ith either parent speies$ o/sprin! of the neFt !eneration are feeble or

sterile(i=e= the tidepool opepod Ti!riopus alifornius)

odes of ,peiation

1= *llopatri(allos0other$ patra0ho#eland)

!ene Jo7 i#peded b9 ph9sial or !eo!raphi barrier

seletion and drift lead to reprodutive isolation

1= ,9#patri(s9#0sa#e$ patra0ho#eland)

ta+es plae in !eo!raphiall9 overlappin! population

an our throu!h hro#oso#e han!es or throu!h nonrando# #atin!

nstant speiation throu!h pol9ploidi8ation

pol9ploid9: eFtra sets of hro#oso#es due to aidents durin! ell division

an autopol9ploid has #ore than " hro#oso#e sets$ all derived fro# one speies

an allopol9ploid has hro#oso#es derived fro# " di/erent speies

i=e= o/ee$ su!ar ane$ bread 7heat$ potatoes$ bananas$ peanuts$ apples

,9#patri speiation via #ehanis#s other than pol9ploid9 is #ore ontroversial

ould our b9 s7ithes in habitat$ food preferene or #ate hoie

debate ontinues over 7hether this is o##on$ and 7hether isolation an persist in

the fae of !ene Jo7

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,9#patri speiation in #a!!ot JiesO

subset of U, populations s7ithed hosts fro# ha7thorn to apple [ "

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1) PUNCTU*TE& E5UL6RU not eFplained b9 &ar7inian theor9

rebuttal: puntuations that appear abrupt in the fossil reord #a9 ta+e tens of

thousands of 9ears

periods of apparent stasis #a9 belie eFtensive biohe#ial han!es not detetable

in the fossil reord

sli!ht !eneti han!es #a9 result in #aWor phenot9pi han!es

The evolution of !enes ontrollin! develop#ent(evodevo) is responsible for

partiular lar!e phenot9pi han!es

Chan!es in Rate and Ti#in!(eterohron9)

nludes:

han!es in the relative !ro7th rates of di/erent bod9 parts(allo#etr9)

han!es in the ti#in! of reprodutive vs= so#ati develop#ent

relativel9 rapid reprodutive !ro7th results in paedo#orphosis seFuall9

#ature adults 7ith Wuvenile #orpholo!9

*llo#atri !ro7th: di/erential !ro7th rates in di/erent bod9 parts

han!es in allo#etri !ro7th lead to di/erenes in hu#an vs= hi#p adults

Paedo#orphi pets

relative to anestral 7olves do#estiated do!s have

softer fur$ lar!er head.e9es$ droopier ears$ sub#issive behavior$ shorter

#u88le

Chan!es in ,patial Pattern

alteration in !enes ontrollin! the plae#ent and or!ani8ation of bod9 parts ause

#aWor evolutionar9 han!e

ho#eoti !enes ontrol bod9 plans b9 ontrollin! the develop#ental fate of !roups

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of ells

the produts of one lass of ho#eoti !enes$ alled oF !enes$ provide positional

infor#ation in ani#al e#br9os

han!es in oF !enes ontrolled evolution fro# Ish Ins to tetrapod li#bs

dupliation of oF !enes a/eted the evolution of vertebrates fro# invertebrates

oF !enes drove evolution of inset bod9 plans

all#ar+s of aroevolution

1) Evolution is not !oal oriented

fossil reord often sho7s apparent trends

i#portant to onsider not Wust the survivin! branh$ but the entire evolutionar9 bush

the appearane of an evolutionar9 trend does not i#pl9 that there is so#e intrinsi

drive to7ard a partiular phenot9pe

1) Evolution &'E,NT eHual pro!ress fro# si#ple to o#pleF

bG all or!anis#s evolved fro# a o##on anestor$ 7e all have as #an9 9ears of

evolution behind us= ,o#e linea!es beo#e #ore o#pleF$ others beo#e si#pliIed

Chi#ps are #ore hi!hl9 evolved than 7e areV

1) Novel features often arise throu!h inter#ediate sta!es$ eah of 7hih serve a

funtion(partial 7in!s an be adaptive)

") Evolution re9les features and puts the# to ne7 uses

#an9 haraters evolved for purposes other than those for 7hih the9 are urrentl9

used( 0DeFaptationD)

feathers evolved for insulation$ oopted for Ji!ht

protein used for ell adhesion in #ultiellular or!anis#s Irst evolved in sin!le

elled hoano9tes

1) Evolution leaves ba!!a!e behind

appendiF(hu#an evolutionar9 ba!!a!e)

trahea and esopha!us share openin!(leads to ho+in!)

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blind spot

Leture >

Chapter "S ,e 1% : Ph9lo!eneti ,9ste#atis

Ph9lo!en9: evolutionar9 histor9 of a speies or !roup of related speies

TaFono#9: siene of na#in! and lassif9in! or!anis#s

,9ste#atis: sientiI s9ste# for lassif9in! or!anis#s

Ph9lo!eneti s9ste#atis: lassiIation of or!anis#s b9 their order of branhin! on

an evolutionar9 tree

'ldshool taFono#9

developed b9 Carolus Linnaus in 1Bth entur9

inludes " part for#at for sientiI na#es(bino#ial no#enlature) and hierarhial

lassiIation s9ste#(e=!= in!don$ Ph9lu#$ Class$ 'rder$ 3a#il9$ -enus$ ,peies

still in use toda9(althou!h &o#ain has been added as the #ost inlusive hierarhial

ate!or9)

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TaFono#i tips

DspeiesD is both the sin!ular and the plural for#

D!enusD is sin!ular$ !eneraD is plural

in a bino#ial na#e$ the Irst letter of the !enus(but not the speies) is apitali8ed$

i=e= o#o sapiens

the entire bino#ial is italii8ed or less o##onl9$ underlined

'ldshool Linnaean ate!ories have been ritii8ed beause the9 dont al7a9s for#

#onoph9leti !roups

*= #onoph9leti

6= paraph9leti

C= pol9ph9leti

Ph9loCode

proposed lassiIation s9ste#

onl9 #onoph9leti !roups 7ould be reo!ni8ed

#ost speies na#es 7ould re#ain unhan!ed

traditional taFono#i ran+s(fa#il9$order$lass===) 7ould no lon!er eFist

o7 to read ph9lo!eneti tree

node: branh point 7here linea!es diver!e

sister taFa

basal taFon

pol9to#9: an unresolved pattern of diver!ene

Ph9lo!enies are inferred fro# ho#olo!ous haraters not analo!ous haraters

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*nalo!ous strutures or #oleular seHuenes that evolved independentl9 are also

alled ho#oplasies

o7 are ph9lo!eneti trees onstrutedO

*= Cladistis is one approah to reonstrutin! ph9lo!en9

!roups speies into lades(anestor and all its desendants)

fouses on shared$ derived haraters

uses priniples of #aFi#u# parsi#on9 or #aFi#u# li+elihood

*= 'ut!roup

a speies or !roup of speies that is losel9 related to the !roup of speies bein!

studied$ but learl9 not as related as an9 stud9 !roup #e#bers are to eah other

= aFi#u# parsi#on9: the best tree reHuires the fe7est han!es

evolution #a9 not be parsi#onious for an9 !iven harater

= aFi#u# li+elihood is an alternative approah to reonstrutin! ph9lo!en9

the bestD tree is the tree 7G the hi!hest li+elihood !iven ertain rules about ho7

&N* han!es over ti#e

#ore o#putationall9 intensive than #aFi#u# parsi#on9 apprahes

Leture 1