3.2 La sélection naturelle trie dans cette diversité

Transcription

3.2 La sélection naturelle trie dans cette diversité
!"#$%&'(&)*"+",*(&-&.*/(0/(&1+#$*'*%/*1+*02*$(
&
&&&&&&&&&&3(2045+*6*($&7$*%%"0
!"# $%&'()*+,-./&/%,01*))*&,1-*&2%/'&+*,,*&2-3*1'-,(
!"#$%&'"($%)#%'"*+%,#-%.-$%/#0&0*"($1%.-$%2+"$$*(34"'-+%."+$%5-%.&%/6*"$-%-0%.7&$$-/8.&3-%&.6&0"*+-%5-$%3&/90-$%."+$%5-%
.&%+-)+"5#20*"(%2+6-(0%5-%.&%5*'-+$*06%"#%8+&$$-(0%5-$%&..9.-$:%;-+0&*($%5-%2-$%&..9.-$%)-#'-(0%<0+-%&'&(0&3-#=1%57&#0+-$%
56$&'&(0&3-#=:%>#-..-$%2"($6,#-(2-$%2-.&%)-#04*.%&'"*+%$#+%.-#+%+6)&+0*0*"(%5&($%.-$%)")#.&0*"($?
!"#$%("#$%*(06+-$$-+"($%5&($%.&%$#*0-%@%#(%)&)*.."(%5-%(#*0%,#*%)&$$-%.&%A"#+(6-%.-$%&*.-$%56)."B6-$%$#+%5-$%0+"(2$%
57&+8+-$C%.&%DE&.9(-%5#%8"#.-&#:%F.%-=*$0-%5-#=%)E6("0B)-$%&.0-+(&0*G$%&#%(*'-&#%5-%.&%2"#.-#+C%8.&(2%0&2E-06%5-%("*+%
HG"+/-%2.&*+-I%-0%-(0*9+-/-(0%("*+%HG"+/-%/6.&(*,#-I:
J#$,#7&#%KL9/-%$*92.-1%.&%G"+/-%2.&*+-%)+65"/*(&*0%.&+3-/-(0:%M-%)+-/*-+%$)62*/-(%/6.&(*,#-%&%606%*5-(0*G*6%-(%KNON%
)+9$%5-%P&(2E-$0-+1%#(-%3+&(5-%'*..-%*(5#$0+*-..-:%Q($#*0-1%.&%G+6,#-(2-%5-$%G"+/-$%/6.&(*,#-$%&%&#3/-(06%)+9$%5-$%
'*..-$%&."+$%,#-%.&%G"+/-%2.&*+-%2"(0*(#&*0%@%)+65"/*(-+%5&($%.&%2&/)&3(-:%R-$%"8$-+'&0*"($%"(0%)-+/*$%5-%/*-#=%2"/S
)+-(5+-%2-%)E6("/9(-:%Q..-$%$-%56+"#.-(0%-(%)&+&..9.-%5&($%#(-%T"(-%+#+&.-%"U%.-$%0+"(2$%5-%8"#.-&#%$"(0%+-2"#'-+0$%
5-%.*2E-($%H)E"0"3+&)E*-%3&#2E-I%-0%5&($%#(-%T"(-%*(5#$0+*&.*$6-%"U%.&%)"..#0*"(%0#-%.-$%.*2E-($%-0%.&*$$-%&))&+&V0+-%.76S
2"+2-%("*+-%5-$%8"#.-&#=%H)E"0"3+&)E*-%5+"*0-I:%W(%2"/)0-%.-$%G"+/-$%"8$-+'6-$%-0%.-$%)"#+2-(0&3-$%5-%2E&,#-%G"+/-%
0#6$%)&+%.-$%"*$-&#=:%M-$%+6$#.0&0$%$"(0%)+6$-(06$%5&($%.-%X&8.-&#%$#*'&(0:%D+")"$-T%#(-%-=).*2&0*"(%@%.&%+6)&+0*0*"(%5-$%
G"+/-$%5-%2"."+6-$%5-$%DE&.9(-$%5#%8"#.-&#%-0%5*0-$%,#-.%$-/8.-%<0+-%.-%G&20-#+%$6.-20*G%@%.7"+*3*(-%5-%2-00-%+6)&+0*0*"(?
!"#$%&'$%()*+,#$%#,#%-,&&.)'$/%&" %0,(1'%2&"+('%'$3%-&.$ %
2(4-3+5.'%'3%6,#2%1,+#$%2,#$,11)'%-"(%&'$%,+$'".78%9&&' %
-()6,1+#'8%!"#$%&'$%()*+,#$%-,&&.)'$%2:'$3%&:+#;'($'8
<"%-()6"3+,#%'$3%+2+%&'%0"23'.(%$)&'23+0%=&"%()6.23+,#%6'%&" %
$.(;+'%6'$%"6.&3'$>8
!"#$%)"#'"($%("#$%*(06+-$$-+%&#=%5*GG6+-(0-$%G&Y"($%5"(0%.&%$6.-20*"(%(&0#+-..-%)"#++&*0%A"#-+%5&($%2-%2&$%&G*(%5-%2"/S
)+-(5+-%.-%)E6("/9(-%5&($%$"(%-($-/8.-:%
;"($*56+"($%#(-%)")#.&0*"(%5-%KZ%*(5*'*5#$1%5-%DE&.9(-$%)&+%-=-/).-:%;-00-%)")#.&0*"(%-$0%$0&8.-%-0%*.%B%&%0"#A"#+$%KZ%
*(5*'*5#$%@%2E&,#-%36(6+&0*"(%H2-+0&*($%(&*$$-(01%57&#0+-$%/-#+-(0I:%[#%56)&+01%*.%B%&%N%8.&(2$%-0%\%("*+$:%M-$%8.&(2$%
5"((-(0%5-$%8.&(2$%-0%.-$%("*+$%5"((-(0%5-$%("*+$:%M-$%8.&(2$%2"//-%.-$%("*+$%5"((-(0%\%5-$2-(5&(0$%@%2E&,#-%36(6S
+&0*"(:%D&+%2"(0+-%5-$%8.&(2$%$"(0%0#6$%)&+%.-$%"*$-&#=%&."+$%,#-%.-$%("*+$%(-%$"(0%A&/&*$%0#6$:%;"/).60-T%.-$%2"#.-#+%5-$%
O%36(6+&0*"($%$#*'&(0-$%-0%2"/)&+-T%.-%)"#+2-(0&3-%5-%("*+$%&#%568#0%-0%&)+9$%O%36(6+&0*"($%)-(5&(0%.-$,#-..-$%.&%$6.-2S
0*"(%(&0#+-..-%&%A"#6:
82,(&9:
!"#$%&'(&)*"+",*(&-&.*/(0/(&1+#$*'*%/*1+*02*$(
&
&&&&&&&&&&3(2045+*6*($&7$*%%"0
;"($*56+"($%/&*(0-(&(0%#(-%)")#.&0*"(%5-%56)&+0%5-%O%*(5*'*5#$C%]%8.&(2$%-0%K%("*+:%^%2E&,#-%36(6+&0*"(1%.-$%8.&(2$%
5"((-(0%\%5-$2-(5&(0$%8.&(2$%&."+$%,#-%.-$%("*+$%5"((-(0%O%("*+$:%R-%).#$1%@%2E&,#-%36(6+&0*"(1%.&%/"*0*6%5-$%*(5*'*5#$%
$"(0%0#6$%)&+%.-$%"*$-&#=1%,#7*.$%$"*-(0%8.&(2$%"#%("*+$:%R-$$*(-T%2-%,#*%$-%)&$$-%)-(5&(0%]%36(6+&0*"($%-01%-(2"+-%#(-%
G"*$1%2"/)&+-T%.-%)"#+2-(0&3-%5-%("*+$%&#%56)&+0%-0%&)+9$%2-$%]%36(6+&0*"($:
_#+%,#-.%)&+&/90+-%.&%$6.-20*"(%(&0#+-..-%A"#-404-..-%*2*?
<"%0)2,#6+3)8
M&%$6.-20*"(%(&0#+-..-%0+*-%5&($%.&%5*'-+$*06%-=*$0&(0-1%-(%A"#&(0%$#+%.&%$#+'*-%"#%$#+%.&%+-)+"5#20*"(1%-0%G&'"+*$-%2-+0&*($%
&..9.-$%&#%560+*/-(0%5-$%&#0+-$:%W(%)-#0%$-%5-/&(5-+%$*%-..-%-$0%.&%$-#.-%G"+2-%6'".#0*'-%,#*%A"#-%$#+%.&%G+6,#-(2-%5-$%
)E6("0B)-$%"8$-+'6$:
!"! $*&4%'%12&5.0*&%0''-&0/&16)*&-78.1,%/,&2%/'&)9(3.)0,-./
!"#$% ("#$ % *(06+-$$"($ % /&*(0-(&(0% @ % 5-#=% &..9.-$ % 560-+/*(&(0% .& % 2"#.-#+ % 5-$ % B-#= % 5- % .& % R+"$")E*.- % H#(-% )-0*0-%
/"#2E-IC%8`%-0%8`ab:%M7-=)6+*-(2-%562+*0-%5&($%.&%c*3#+-%5-%.&%)&3-%$#*'&(0-%2"(2-+(-%K\Z%)")#.&0*"($%5-%Kd%*(5*'*S
5#$%2E&2#(-:%;E&,#-%)")#.&0*"(%$-%+-)+"5#*0%*$".6/-(0%-0%"(%(-%3&+5-%@%2E&,#-%G"*$%,#-%Kd%*(5*'*5#$1%)+*$%&#%E&$&+5%
)&+/*%.-$%5-$2-(5&(0$%5-%2E&,#-%)")#.&0*"(:%F.%B%&%0"#A"#+$%5"(2%]\%&..9.-$%)&+%)")#.&0*"(%H.-$%R+"$")E*.-$%$"(0%5*S
)."e5-$%5"(2%2E&2#(-%&%5-#=%&..9.-$I:%R&($%2E&2#(-%5-$%K\Z%)")#.&0*"($%"(%,#&(0*G*-%.-%("/8+-%57&..9.-$%8`ab%@%
2E&,#-%36(6+&0*"(:%
M"+$,#7*.%B%&%Z%&..9.-$%8`ab%27-$0%,#7*.%B%&%KZZf%5-%8`%-0%"(%6.*/*(-%.&%)")#.&0*"(%5#%2"/)0&3-C%-..-%+-$0-+&%0"#A"#+$%@%Z:%
^%.7*('-+$-1%,#&(5%*.%B%&%]\%&..9.-$%8`ab%27-$0%,#7*.%B%&%KZZf%5-%8`ab%-0%Zf%5-%8`:%W(%6.*/*(-%&#$$*%.&%)")#.&0*"(%,#*%
+-$0-+&%0"#A"#+$%@%]\:
82,(&9;
!"#$%&'(&)*"+",*(&-&.*/(0/(&1+#$*'*%/*1+*02*$(
&
&&&&&&&&&&3(2045+*6*($&7$*%%"0
[#%56)&+0%0"#0-$%.-$%)")#.&0*"($%$"(0%&#0"#+%5-%Kd%&..9.-$%8`ab%H-0%5"(2%Kd%&..9.-$%8`I:%>#-%+-/&+,#-$%'"#$%&)+9$%KL%
36(6+&0*"($?
?,.$%&'$%2"$%$,#3%-()$'#3$@%&"%0()5.'#2'%6'%&:"&&A&'%BCDE%"%;"(+)%".%F"$"(6%'3%,#%,B$'(;'%1"+#3'#"#3%3,.3'$%&'$%0()5.'#2'$8
82,(&<=
!"#$%&'(&)*"+",*(&-&.*/(0/(&1+#$*'*%/*1+*02*$(
&
&&&&&&&&&&3(2045+*6*($&7$*%%"0
R&($%2"/8*-(%5-%)")#.&0*"($%#(%&..9.-%H8`%"#%8`abI%&404*.%606%G*=6%H$&%G+6,#-(2-%-$0%&++*'6-%&%KZZfI?
G&%4%"%";"+3%HIJ%-,-.&"3+,#$%".%6)-"(3/%+&%'#%('$3'%KL8%M#%"&&A&'%"%6,#2%)3)%0+7)%6"#$%ED%-,-.&"3+,#$8%!"#$%HN%2:'$3%&:"&&A&'%BC %
5.+%"%)3)%0+7)/%6"#$%LO%2:'$3%&:"&&A&'%BCDE8
D"#+,#"*%.-$%G+6,#-(2-$%&..6.*,#-$%'&+*-(04-..-$?
&'$%0()5.'#2'$%;"(+'#3%"&)"3,+('1'#3%2"(%,#%)2F"#3+&&,##'%".%F"$"(6%6"#$%&'$%6'$2'#6"#3$8
;-%)E6("/9(-%-$0%("//6%56+*'-%36(60*,#-%-0%*.%-$0%+6&.*$6%(&0#+-..-/-(0%)&+%.&%+-)+"5#20*"(C%0"#$%.-$%&..9.-$%(-%$"(0%
)&$%+-)+"5#*0$%-0%)+6$-(0$%@%.&%36(6+&0*"(%$#*'&(0-:
!"#$%&'(")"*$+,&C%/"5*G*2&0*"(%&.6&0"*+-%5-$%G+6,#-(2-$%&..6.*,#-$%+-)"$&(0%$#+%.762E&(0*.."((&3-%&#%E&$&+5%5-$%3&S
/90-$:
F.%)-#0%<0+-%+-)+6$-(06%57#(-%G&Y"(%5*GG6+-(0-:%R&($%.&%c*3#+-%$#*'&(0-%-$0%5*+-20-/-(0%+-)+6$-(06-%.&%G+6,#-(2-%&..6.*,#-%
5-%O%)")#.&0*"($%5-%\b%*(5*'*5#$%&#%2"#+$%5#%0-/)$:%R-%.&%/</-%G&Y"(1%"(%+-/&+,#-%,#-%.g#(%5-$%5-#=%&..9.-$%G*(*0%)&+%
$-%G*=-+1%&#%E&$&+5:
D-($-T%'"#$%,#-%.-%0-/)$%5-%G*=&0*"(%57#(%&..9.-%)&+%56+*'-%$"*0%).#$%."(3%5&($%#(-%3+&(5-%"#%5&($%#(-%)-0*0-%)")#.&S
0*"(?%J#$0*G*-T:
9#%1,4'##'/%6"#$%.#'%-'3+3'%-,-.&"3+,#/%&'%F"$"(6%".("%-&.$%6:+#0&.'#2'%)3"#3%6,##)%5.:+&%4%"%-'.%6'%*"1A3'$%6+00)('#3$%'3%5.' %
5.'&5.'$%P3+("*'$P%".%F"$"(6%$.00+(,#3%Q%)&+1+#'(%.#%6'$%"&&A&'$8
W(%5*0%,#-%.-$%/#0&0*"($%,#*%(-%$"(0%)&$%$"#/*$-$%@%.&%$6.-20*"(%(&0#+-..-%$"(0%h%(-#0+-$%i:%Q..-$%(-%$"(0%$"#/*$-$%&."+$%
,#7@%.&%56+*'-%36(60*,#-:%M76'".#0*"(%)&+%56+*'-%36(60*,#-1%$&($%$6.-20*"(1%-$0%562+*0-%)&+%.&%0E6"+*-%(-#0+&.*$0-%5-%.76'".#S
0*"(:%D-($-T4'"#$%,#-%.&%G*=&0*"(%57#(%&..9.-%(-#0+-%-$0%).#$%+&)*5-%"#%/"*($%+&)*5-%,#-%.&%G*=&0*"(%57#(%&..9.-%$"#/*$%@%
.&%$6.-20*"(%(&0#+-..-?%J#$0*G*-T:
<"%0+7"3+,#%6:.#%"&&A&'%#'.3('%'$3%&'%0(.+3%6.%F"$"(6%"&,($%5.'%&"%0+7"3+,#%6:.#%"&&A&'%$,.1+$%Q%$)&'23+,#%'$3%-(,;,5.)'%-"(%.#'%
1,(3"&+3)%,.%.#'%0)2,#6+3)%6+(+*)'$8%<"%0+7"3+,#%6:.#%"&&A&'%$,.1+$%Q%.#'%$)&'23+,#%-,$+3+;'%$'("%6,#2%'#%1,4'##'%-&.$%("-+6'%5.' %
2'&&'%6:.#%"&&A&'%#'.3('8
82,(&<>

Documents pareils