Lecture 7 - dr.lahti PDF

Preview

Summary

dr.lahti...

Description

Le c t ur e7:Ada pt a t i on1 “ Or g a ni s ma lt r a i t sa r ef a s hi one dt hr oughe v ol u t i onb yna t ur a ls e l e c t i on” t h eonl ye v ol ut i ona r yme c ha ni s mt h a ti mpr o v e su p onf u nc t i on a li n t e gr i t yi sna t u r a ls e l e c t i on  Na t ur a ls e l e c t i ons i nc eDa r wi n :  Pa t t e r nso fn a t ur a ls e l e c t i on:  Al r e a d ygi v e no ne :f r e q ue nc yd e pe nde ntn a t u r a ls e l e c t i on:r e s ul t si ni n c r e a s i n gv a r i a t i on.  The r ea r e3o t h e rt y pe s :t r a i tv a l ueonx a x i s ,fit ne s sony a xi s  Di r e c t i onals e l e c t i on: o De pe nd sona n yo neo ft het hr e egr a p hs ,wha t e v e r t r a i tv a l uet a l k i n ga bou tt hei n di v i dua l so nt her i ght s i dewi l la l wa y sbemor efitt hant hel e f t  Ex .Ru nn i n gs p e e di npr e da t or sa n di npr e y ( nos uc ht hi n ga sr unni n gt o of a s t ,f a s t e ry ou r u nbe t t e ry ouwi l le i t he rc a t c hpr e yore s c a pe pr e da t o r )  St abi l i z i ng( ba l a n c i n g )s e l e c t i o n o The r ei sapar t i c ul art r a i tl e v e lt hati sbe ne fic i a l t oy ouandi fy ouv a r yf r o mt hel e f tort her i g ht , y ouwo n’ tbea sfit .Fi r s ty ouha v eal o tofv a r i a t i on , a ndt heone so nt hee xt r e mewi l ldi ea n dy oug e tap i n c hi n gt og e t he roft he pop ul a t i onu nt i ly oug e tahi ghp e a ka tt hebe t t e rt r a i tv a l ue  Hu ma nb a b yb od ys i z e( he a ds i z e )a ndb odywe i g ht :t ool o wabod y we i ght =e a s yf ormo mt obi r t hb utl e s sl i k e l yf orb a b yt os u r vi v e ,t o oh i g h abodywe i gh t =mot he rc a nd i ei nc h i l dbi r t ho rc hi l d ,s ot he r ewa s s t a bi l i z i n gs e l e c t i onf ori nt e r me d i a t eb odys i z e .  Di s r upt i v e( di v e r g e nts e l e c t i on) o Oppo s i t eo fs t abi l i z i ng,c anal s obec a l l e ddi v e r g e nts e l e c t i on,wha ti t ’ s doi ngi st he r ea r et woo rmo r emode so fpe akfit ne s sbutbe t we e nt he m t he r ei sr e duc e dfit ne s s  Fort h ea l t e r na t i v er e pr odu c t i v es t r a t e gi e s :i ft he ywe r eg e ne t i ci ns t e a do f pl a s t i ca n dy ouwe r eama l efis ht h a twa ss ma l l e rt h a nanor ma lma l ebu t no ts ma l le n ou ght ob eaf e ma l e , y ouwo ul dg e tb e a ton,s i n c et he r e pr oduc t i oni nt he s efis hi sb od ys i z eba s e dt ha twoul dbeb a d.  Ex .I ns e e dc r a c k e r si nnor t hAf r i c a ,oneha sas ma l ls e e da n do neha sa l a r g e rs e e d,l a r g e rbi l l sg ooda tbr e a ki n gh a r d,bi gs e e d .Sma l lbi l lc a n ’ t br e a kbi gs e e db u tc a nbr e a ks ma l ls e e d ,l a r g ebi l l st ooc l ums yf ors ma l l s e e d .I fy ouha dame di umbe a k,t ooc l u ms yf ors ma l ls e e da n dt o owe a k f orl a r g e ,s oy o uwo u l ds t a r v e .  Fi s he r ’ sf undame nt a lt he or e mo fNa t ur als e l e c t i on  Ther a t eofi nc r e as ei nfit ne s so fapopul a t i oni se qualt oi t sg e ne t i cv a r i anc ei nfit ne s s  Apopul a t i onh a safit ne s s ,i fy out a k ea l lt heba bi e st he r eha v eb e e ns of a r( ori nt he f ut ur e ) ,a ndy out a k et h ea mo untofp e opl ei nt hec l a s s r ooma nda v e r a g ei tf or a b s ol ut efit ne s s ,unde rn a t u r a ls e l e c t i ont hea bs ol ut efit ne s ss ho ul di nc r e a s e .  Tha t ’ snott hepur pos eo fnat ur a ls e l e c t i o n,i tdoe s n’ tope r a t ea tt heg r oupl e v e l , i to pe r a t e satt hei ndi vi duall e v e lbuto neo ft hee ffe c t sofe v ol ut i o nbyna t ur al s e l e c t i o ni st hatt hea v e r a g efit ne s sofapo pul a t i oni nc r e as e so v e rg e ne r a t i ons .  g e ne t i cv a r i anc ei nfit ne s s :he r i t a bl ev ar i a t i oni nt r a i t si mpo r t a ntt o r e pr oduc t i v es uc c e s s .

Ex .I fs i z ei nflue n c e dfit ne s s ,( =c ha n g ei nW=fit ne s s )i f y ou ’ r ebi g ,y our e pr o duc emo r e .I fy oua r es ma l ly oudon ’ t r e pr odu c e .Ri g htha shi ghg e ne t i cv a r i a n c ei nfit ne s s ( a s s umi n gs i z ei sg e ne t i c a l l yv a r i a bl e )b e c a us et he r e ’ s s omel i t t l ei ndi v i dua l sa nds o mel a r g ei n di v i dua l s .I nt he pop ul a t i onwi t hl o wWpop,l e f ty ouha v el o wg e n e t i c v a r i a n c ei nfit n e s sbe c a us et he y ’ r ea l lt hes a me . o I fy oukno wt h a ts i z ei si mpor t a n tt og e ne t i cv a r i a nc eo fap opul a t i ont he ny ou c a nt e l lho ws l o wo rh o wf a s tt hepopul a t i oni se v ol v i n gs i mp l yb yl o oki n ga t ho wmu c hv a r i a t i ont h e r ei si nt h a tt r a i t .Youwoul dl oo ka tt hepop ul a t i ona nd s da yt he r e ’ shi g hg e ne t i cv a r i a n c es ot h a tme a nsi t se v ol vi n gr e a l l yq u i c kl y ,t he pop ul a t i onwi t hl o wg e ne t i cv a r i a n c ey ouwo ul ds a yi t se v ol vi n gh a r dl ya ta l l . Ada pt a t i on ,e n v i r on me n t ,a n df unc t i on  Thee n vi r onme nti st het oolo fe v o l u t i onb yn a t ur a ls e l e c t i on,i td e t e r mi ne swhe t he ry ou s ur vi v ea ndr e pr oduc eo rnot .Ev ol ut i oni spr o gr e s s i n gt ofitt h ee n vi r onme nt  Noa d a pt a t i onwi t h ou tf unc t i on  Not hi n ga d a pt su nl e s si td oe ss ome t hi n gf o rt heor g a ni s m  Func t i oni sde pe nde n to nt hee n vi r o nme n t  Ev o l ut i oni sp r o gr e s s i n gt ofitt hee n vi r o nme nt  Func t i onsu s ua l l yl e a d st oa da pt a t i on  I fat r a i th a saf un c t i on( e x.Yo u re a r sa l l o wy out ohe a r )na t ur a ls e l e c t i onwi l lt e ndt of a v or i mp r o v e me n t st ot ha tf unc t i on .I ft ha tt r a i tdoe ss ome t hi ngf ort heo r g ani s ma nd e nhanc e si ts ot ha ti tbe ne fit st he i rs ur vi v alandr e pr oduc t i on,t he nna t ur a ls e l e c t i o n wi l lt e ndt of a v ort hee nhanc e me ntofi t .  En vi r o nme nt sa ndf un c t i onsc ha n g e  Envi r onme nt sc hangeandwhe nt he yc hang ef unc t i onsc hang e  Ex .Fos s i l i z e dwi n gofa ni ns e c t ,e vi de nc es u g g e s t st h a ti ni t i a l l ywhe nwi n g se v o l v e d i ni ns e c tt he ywe r en otf orfli g htb utr a t h e ra sat he r mo r e g ul a t o r yd e vi c e ,t he ywe r e t oowe a kt ofly ,s oa tfir s ti twa sf orc o l l e c t i n gh e a torf ord i s s i pa t i n gh e a ta ndo v e r t i met h ef unc t i onc ha n g e da n di n s e c t swe r et hefir s to r g a ni s mt ofly .  En vi r o nme nt so f t e npos et r a de o ffs  Wh e ny o uc a n ’ topt i mi z et wod i ffe r e ntf unc t i o ns ,s oy ouh a v et oc ompr omi s eb e t we e nt he m  Ex .Re dbr e a s t e dg o os et r a deoffp r e da t i onf r om f a l c o n st ogr oundpr e yi n gp r e da t or s l i k ef o x e swhoa r ea l s oa f r a i doft hef a l c o ns .I ft he yn e s tt oof a rf r o mt heh a wks ,t h e f o x e swi l lg e tt he ma ndt he i re g g s ,buti ft he yne s tt ooc l os et ot hef a l c ont hewi l lb ea t r i s koft hef a l c o n,s ot he yn e s ti na ni n t e r me di a t ea r e a ,t he yt r a de off,s ot hef o x e sa r e a f r a i dt oc omec l os eb e c a us eoft h ef a l c o na n dt hef a l c o nc a n ’ ts e et he m.Tr a d e off be c a u s et he ys t i l lg e tpr e y e do nb ybo t ht hef o xa ndt hef a l c o n St ud i e so fa d a pt a t i on  ho wdoy out e s ti nna t u r ewhe t h e rat r a i ti st her e s ul tofn a t ur a ls e l e c t i on?  Pa s tadapt at i o n:c ompar a t i v eme t hod  T wor e s e a r c hs t r a t e g i e s : 1) Lookf ore v ol ut i ono fs i mi l a rt r a i t si ns i mi l a re n v i r onme nt si ndi s t a nt l yr e l a t e d or g a ni s ms( c onv e r g e nc e )  Ex .Wh i t ec oa t si ns no wye n vi r on me n t s :p ol a rbe a r ,a r c t i cf o x,s no wyo wl , a r c t i cwol v e sa l ldi s t a n t l yr e l a t e dbuti n de p e nde nt l ye v ol v e dwhi t ef urt o ma t c ht h ee n vi r onme ntc a nf unc t i oni nc a moufla g e o







2) Lookf ore v ol ut i ono fdi ffe r i n gt r a i t si nd i ffe r e nte n v i r o n me nt s ,i nc l o s e l yr e l a t e d or g a ni s ms( di v e r g e nc e )  Ex .Fl y i n gf o x e s ,aki n do fb a t&t he r e ’ st onsofd i ffe r e nts pe c i e sa n dd i ffe r e n t s pe c i e sha v edi ffe r e n tg r o ups i z e s( s oc i a le n vi r o nme n ts t i l lc ount sa s e n vi r on me nt ) .Se xua ls e l e c t i o nt he o r ypr e di c t st ha ti nal a r g eg r oupss i z e wh e r ema l e sc o mp e t e sf orma t e s ,t h ebi gg e rt hegr oups i z e ,t h emo r ema l e s c o mpe t e . Onema l ec a nmon opol i z ema n yf e ma l e ss os omec a ng e tl e f ta l one , o f t e nt i me sc ompe t i t i o ni swhoc a ni ns e mi na t et hemos tf e ma l e ss ot hema l e s c a nc ompe t ewi t he a c ho t he rb yt r y i n gt oi n s e mi na t ea sma n yf e ma l e sa s p os s i bl es ot h ep r e d i c t i onf r om e v o l ut i o na r yt he or yi st h a tl a r g e rt e s t e swo ul d e v o l v ei nba t st ha tha v el a r g e rg r oups i z e s .Whe nou ta ndf oundt het he o r yt o b ec or r e c t . Cur r e nta dapt i o n:fie l ds t udi e s  Thei de a ls t udywoul ds ho w:( ha r de ra ndh a r de ra sy oug oup) 1 ) Pr e di c t e dpa t t e r nsofv a r i a t i oni ndi ffe r e n te n vi r onme nt s  Us ee v o l ut i ona r yt he or yt oma k eapr e di c t i on  Ex .Re ds e aha sahi ghe rs e ac ont e ntt ha nMe di t e r r a ne a n,s ot i l a pi ai nr e ds e a ma yha v eh i g he r /mor ep o we r f ulos mot i cr e g ul a t i ont ha nt i l a pi af r om t he Me d i t e r r a ne a n .I fy oufindt ha tmo v et os e c o n ds t e p 2 ) He r i t a bi l i t y  Loo kf org e ne st ha tunde r l i et het r a i t ,pe r f or me x pe r i me n t st os h o wt ha ti t ’ sa n e v o l ut i ona r yt r a i ta n dn otapl a s t i co ne 3 ) Fu nc t i on  Ta k et ha tt r a i ta n dt e s tt het r a i ti nn a t u r et os e ei fi t sf unc t i ona l 4 ) Pr e di c t e dc h a n g eo v e rt i me  Ha r de s tt od o,s ho wapr e di c t e dc h a n g eo v e rt i me .  Ex a mpl e so fa d a p t a t i on 1 .( e v o l u t i ono f )Mo r phol o gy( s t r uc t ur e si ny ourb od y)a n dp h y s i ol ogy( pr o c e s s e si ny ou r bod y )  Cons t r a i n t s( l i mi t sonwh a tc o ul de v o l v e ) a . Ae r obi cr e s pi r a t i o ni na ni ma l s  Ne v e rb e e na nan i ma li ne v ol ut i ona r yt i met h a tdo e sn otu nde r g oa e r obi c r e s pi r a t i on. b . Ea r l yde v e l opme n t( butwai t ! )  Ea r l yd e v e l opme nts e e me dt oe v o l v eo nc eo v e rt i me .I ffir s ti n v a g i na t i ono f bl a s t opor ei smout ht he ni t ’ sapr o t os t ome , i fi t ’ st hea nust he ni t ’ sa de ut e r os t ome .The s et wod e v e l op me nt a ls t y l e ss e e me dt oha v ee v ol v e do nl y onc ebutNO  t hepe ni swor m,t he ya r ep r ot os t o me sb yd e s c e n tb utt h e yha v ee v ol v e da de ut e r os t omee mbr y o ni cd e v e l opme n t .The y ’ r enotr e l a t e dt od e ut e r os t ome butwhe nwel oo ka tt he i rd e v e l opme nt ,t he yd e v e l o pj us tl i k e de ut e r os t ome sd oe v e nt hou ght he y ’ r epr ot os t ome s .I t sc o nv e r g e nc e ,no t ne c e s s a r i l ybe c a us eoff unc t i on c . An i ma lc e l l sc a nno tl oc omo t ea ndd i v i des i mu l t a ne ous l y  The yn e e dmi c r ot ubu l e sf ormo v e me nta swe l la sdi vi s i o n,c a n ’ tr e pr odu c ea t s a met i met he y ’ r emo v i n g d . Te t r a po dsh a v ef o url i mbsa n dfiv edi g i t s  Ca nl os es o mebu tne v e rg a i nt he m

s omepe o pl eh a v es ug g e s t e dt ha tt hepa nd ah a sa ne xt r at hu mbbuti t ’ sr e a l l y j us ta ne x t e ns i onf r om t hewr i s tb oneb otat r u et humb e . Col orv i s i oni np r i ma t e s( butwa i t ! )  Ne wwo r l dmonk e y swe r et hou ghtt oh a v eonl yt woc o ne s -b ed i c hr o ma t i c . I t ’ s be e ns ho wnr e c e n t l yt ha tt he ya c t ua l l yha v eabr oa dv a r i e t ys o meh a v e4,s ome ha v e3,a n dt he r e ’ so net ha te v ol v e dano c t ur na ll i f e s t y l ea ndh a sonl yo nec o n e  Youha v et ot e s ti t ,whe ny o ut hi nks ome t hi n gi sac ons t r ai nt ,y o uc o ul dbewr on g. ...