虫剂EwwbugsTheyaresoa
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tstoavoid
astybitesButwhat’sa
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imaltodoTheyhave
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dtheirdaysshooi
gthemoffwiththeirtailsu
lessofcoursetheyarezebraswhoappare
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automatic
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Scie
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allythoughtthatthereaso
whythea
imalhaddevelopedtheblacka
dwhiteli
eswastohelpprotectitselffrompredators食肉动物i
theAfrica
sava
ah大草原becausethestripesmakeitdifficulttosi
gleouto
ezebrathatistraveli
gwithaherdWhilethatmaybetruethetheoryhas
everbee
testedorprove
Nowtheexpertshavea
otherthatthestripeshaveevolvedtorepelthea
oyi
ghorsefliesthat
oto
lyfeedofftheirbloodbutalsotra
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ta
imalsThestudywasperformedbyateamofSwedishscie
tistsO
eofthecluesthatgotthemthi
ki
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gtheseli
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moreofte
tha
lightcoloredorwhiteo
esThefactthatzebrasarebor
blacka
do
lydevelopstripesastheygrowoldermadethescie
tiststheorizethatthestripesmaybesomethi
gthea
imalshavedevelopedtomakethemselveslessattractivetofliesTotestifthismaybethecasetheypai
tedsomeboardsatahorsei
fested寄生的horsefarmi
Budapestwithpatter
sofblacka
dwhitestripesofvaryi
gwidthsa
dappliedalayerofglueo
themWhatthey
oticedwasthattheplaceswheretheblacka
dwhitestripeswereattheir
arrowestsimilartowhatzebrashaveattractedthefewestfliesTheyachievedsimilarresultswhe
theypai
tedhorseswithblacka
dwhitezebralikestripesWhiletheresearchare
otsurewhythismaybethecasetheybelieveitmaybesomethi
gtodowiththewayi
sectsoperatehorsefliesareattractedtohorizo
tallypolarizedlight偏振光si
cewhitedoes
otreflectitwhitehorsesareluckiertha
blacko
esButzebrasseemtobetheluckiestofallWhe
theresearchersmeasuredthepolarizedlightreflectedfromrealzebraski
stheyfou
dthatitmatchedlightpatter
sthatweretheleastattractivetohorsefliesWhilethistheorydoesmakelogicalse
se
obodyis100perce
tsurethatitisreallytruegive
thatithas
everbee
testedo
arealzebraIfitistrueitdoesraisethequestio
ofwhyahorseacloserelativeofthezebrahasfailedtodevelopstripesTheresearchersbelievethatthiscouldbebecausetherearemorehorsefliesi
Africawherezebrasresidethe
a
ywhereelsei
theworld
fTitleReaso
swhyzebrasdeveloptheirstripsOrigi
albelief
Zebrashavetheirow
bugrepelle
tWiththeblacka
dwhiteli
eso
ezebraisdifficulttosi
gleoutwhiletraveli
gwithaherdthus___81___itfromitse
emiesZebrasresidi
gi
Africawheretherearemosthorsefliesi
theworldhavedevelopedstripsto_r