human nature 9 - origin of species

8/10/2019 Human Nature 9 - Origin of Species

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Darwin: Origin ch. 7


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Is the Diference between Animalsand Humans one o degreeor okind?

Can morality be explained by naturaleolution?

Is Human !ature fxedor in a

constant state o ux?


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Diine desi"n theory. #amarc$ism


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%he &renchnaturalistJean-Baptiste Lamarckdeeloped a theory

o eolutionaccordin" to whichan organism canpass oncharacteristics

that it acquiredduring itslietimeto itsospring.


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#amarc$ism#amarc$ism%wo principles:%wo principles:

'se and Disuse'se and Disuse

Inheritance oInheritance o

ac(uired traitsac(uired traits


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) main principles: *a+ Use and disuseUse and disuse , Indiiduals

lose characteristics they do not use

and they deelop othercharacteristics that are useul.

*b+Inheritance o acquiredInheritance o acquired

traitstraits , Indiiduals inherit the traitsthat their ancestors hae ac(uiredthrou"h use.


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-eolo"ical time. *#yells Principles ofGeology/ 0123+

-reat amount o ossil remains or

traces o animals/ plants andor"anisms rom the remote past.


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I durin" the lon" course o a"es and under aryin"conditions o lie/ organic beings ar!organic beings ar! at all in the seeralparts o their or"ani4ation/ and I thin$ this cannot bedisputed5 i there be/ owin" to the hi"h "eometrical powerso increase o each species/ at some a"e/ season/ or year/ aseere struggle or liestruggle or lie/ and this certainly cannot bedisputed5 then/ considerin" the in6nite complexity o the

relations o all or"anic bein"s to each other and to theirconditions o existence/ causin" an in6nite diersity instructure/ constitution/ and habits/ to be adanta"eous tothem/ I thin$ it would be a most extraordinary act i noariation eer had occurred useul to each bein"s ownwelare/ in the same way as so many ariations hae

occurred useul to man. 8ut i ariations useul to anyor"anic bein" do occur/ assuredly indiiduals thuscharacteri4ed will hae the best chance o bein" presered inthe stru""le or lie5 and rom the stron" principle oprinciple oinheritanceinheritance they will tend to produce of9sprin" similarlycharacteri4ed. %his principle o preseration/ I hae called/

or the sa$e o breity/ "atural #election.*Darwin/ Origin ch. / ;


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$ariation% *= %he act that ofsprin" aryamon" themseles/ and are not carboncopies o an immutable type.+

#truggle or lie#truggle or lie*= %he principle which

determines the ariations that will beadanta"eous in a "ien enironment/thus alterin" the species throu"h selectiereproduction.+

InheritanceInheritance%*= %he orce that transmitssimilar or"anic orm rom one "enerationto another+


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I many ofsprin" must die *or not all can beaccommodated in natures limited ecolo"y+/and indiiduals in all species ary amon"themseles/ then on aera"e *as a statistical

statement/ and not in eery case+/ suriorswill tend to be those indiiduals with ariationsthat are ortuitously best suited to chan"in"local enironments.


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Does Darwin do away with teleolo"y/or is there some sort o teleolo"y inthe theory o eolution by natural

selection? Beection o the idea o designdesign.

reseration o the notion o purposepurpose. *%he

chan"es that occur are not "oin" to becompletely due to luc$5 e.". the eolutionistis "oin" to be able to study thepurposeocertain or"ans+


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In a way/ Darwin does away with teleolo"y/since it replaces speci6c Diine desi"ns withthe actions o an impersonal& purel!

ph!sical process*natural selection+. Howeer/ Darwin himsel seems to thin$that his system has presered teleolo"y in away. *&inal causationEnatural purpose does

not necessarily inole bein" the product oan intentional desi"n,F the notion onatural selection includes certain teleolo"y+


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-ray:Ge reco"ni4e the "reat serice rendered byDarwin to natural science by restorin" teleolo"y toit/ so that instead o haing morpholog!instead o haing morpholog!

against teleolog!& 'e shall hae henceorthagainst teleolog!& 'e shall hae henceorthmorpholog! married to teleolog!morpholog! married to teleolog!.G Nature/ >une/ 017.

Darwin:G(hat !ou sa! about teleolog! pleases me(hat !ou sa! about teleolog! pleases me

especiall!especiall!/ and I do not thin$ anyone else eernoticed the point. I hae always said that you werethe man to hit the nail on the head.G *(uoted in

Autobiography/ p. 231+


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A. -ray is one o the mostinuential American botanists othe 0thCentury. He is best$nown or his extensie wor$ ontaxonomy *see esp. his Manualof the Botany of the NorthernUnited States, fro Ne!"ngland to #isconsin and Southto Ohio and Pennsyl$ania%nclusi$e, 011&

Ima"e:

Asa -ray by >ohn hipple/ 01@


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%here is a bi""er resistance to acceptthe explanation o the inheritance o

a pattern o behaior than theinheritance o a morpholo"icaleature,why?


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%here is a bi""er resistance to acceptthe explanation o the inheritance oa pattern o behaior than the

inheritance o a morpholo"icaleature,why?Appearance o intelli"ent

"uidance.


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An action/ which we ourseles shouldre(uire experience to enable us toperorm/ when perormed by an animal/

more especially by a ery youn" one/'ithout an! experience'ithout an! experience/ and whenperormed by many indiiduals in thesame way/ 'ithout their kno'ing or

'hat purpose it is perormed/ is usuallysaid to be instinctie.

'Origin / ch. 7/ 0&


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How unconsciously many habitualactionsare perormed/ indeed not rarelyin direct opposition to our conscious willJ

Ket they ma! be modifed b! the 'ill orreason. Habits easily become associatedwith other habits/ and with certain periodso time and states o the body. hen once

ac(uired/ they oten remain constantthrou"hout lie.

'Origin / ch. 7/ 0&


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I we suppose any habitual action to becomeinheritedLand I thin$ it can be shown thatthis does sometimes happenLthen the

resemblance between what ori"inally was ahabit and an instinct becomes so close as notto be distin"uished. I Mo4art/ instead oplayin" the pianoorte at three years old withwonderully little practice/ had played a tunewith no practice at all/ be mi"ht truly be saidto hae done so instinctiely. *ch. 7/ p.)+


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N8ut it would be the most serious error tosuppose that the "reater number oinstincts hae been ac(uired by habit inone "eneration/ and then transmitted by

inheritance to succeedin" "enerations. Itcan be clearly shown that the mostwonderul instincts with which we areac(uainted/ namely/ those o the hie9beeand o many ants/ could not possibly haebeen thus ac(uired.O *ch. 7/ p.)+


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NIt will be uniersally admitted that instincts areas important as corporeal structure or thewelare o each species/ under its presentconditions o lie. 'nder chan"ed conditions olie/ it is at least possible that sli"htmodi6cations o instinct mi"ht be pro6table to aspecies5 and i it can be shown that instincts doary eer so little/ then I can see no diPculty innatural selection preserin" and continuallyaccumulatin" ariations o instinct to anyextent that may be pro6table.O *ch. 7/ p.)+


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-eolo"ical time scaleN!o complex instinct can possibly be

produced throu"h natural selection/ except

by the slow and "radual accumulation onumerous/ sli"ht/ yet pro6table/ariations.O *ch. 7/ p.)+

N!atura non acit saltumO , %his

principle Napplies with almost e(ualorce to instincts as to bodily or"ans.O*Ch. 7/ p.)+


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Coc$oos instinct to lay her e""s inother birds nests

Ants slae9ma$in" instinct Hie98ees Cell9Ma$in" instinct


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NQthe most wonderul o all $nowninstincts/ that o the hie9bee/ can beexplained by natural selection hain"ta$en adanta"e o numerous/ successie/

sli"ht modi6cations o simpler instincts5natural selection hain" by slow de"rees/more and more perectly/ led the bees tosweep e(ual spheres at a "ien distance

rom each other in a double layer/ and tobuild up and excaate the wax alon" theplanes o intersection.O


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%he bees/ o course/ no more $nowin"that they swept their spheres at oneparticular distance rom each other/

than they $now what are the seeralan"les o the hexa"onal prisms and othe basal rhombic plates.%he motie

power o the process o naturalselection hain" been economy owax5 QO *ch.7/ p. 0+


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N... one special diPculty/ which at 6rstappeared to me insuperable/ and actuallyatal to my whole theory. I allude to the

neuters or sterile emales in insect-communities: or these neuters otendifer widely in instinct and in structurerom both the males and ertile emales/

and yet/ rom being sterile& the!cannot propagate their kind.O

'Origin / ch. 7/ 0&


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N... %his diPculty/ thou"h appearin" insuperable/is lessened/ or/ as I beliee/ disappears/ when it isremembered that selection ma! be applied toselection ma! be applied tothe amil!the amil!/ as well as to the indiidual/ and maythus "ain the desired end. ... %hus I beliee it has

been with social insects: a sli"ht modi6cation ostructure/ or instinct/ correlated with the sterilecondition o certain members o the community/has been adanta"eous to the community:conse(uently the ertile males and emales o the

same community ourished/ and transmitted totheir ertile ofsprin" a tendency to produce sterilemembers hain" the same modi6cation.O

'Origin / ch. 7/ 0R&

human nature 9 - origin of species

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