際際滷

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Rashedul Azad

Wavy hair may have evolved in early humans as an adaptation to high ultraviolet light in Africa. Straight hair allows UV light to penetrate deeper into the scalp, whereas wavy hair provides more protection. As humans lost body hair and skin darkened, wavy or curly hair would have helped block UV penetration compared to straight hair near the equator. Later, as people migrated to less sunny areas, straight hair may have evolved to help increase UV absorption when skin became paler.

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Additional data:Humantransformativehereditaryqualities Surface Wavy hair Man withwavyhair(DavidLuiz) Jablonski attestsheadhairwasdevelopmentallyprofitable forpre-peopletoholdsince itensuredthe scalpas theystrolleduprightinthe extreme African(tropical) UV light.Whilesome maycontendthat, by thisrationale,people oughttolikewise expressfurry shouldersinlightof the factthat these body parts wouldputativelybe presentedtocomparative conditions,the insurance of the head,the seatof the cerebrumthat empoweredhumankindtowindupa standoutamongstthe bestspeciesonthe planet(andwhichlikewiseisexceptionallypowerlessduringchildbirth) wasseeminglyamore dire issue (axillaryhairinthe underarmsandcrotch were additionallyheldasindicationsof sexualdevelopment). At some pointamidthe steadyprocessbywhichHomoerectusstarteda move fromfuzzyskinto the exposedskincommunicatedbyHomosapiens,haircompositionputativelystepbystepchangedfrom straighthair[citationneeded] (the state of mostwell evolvedcreatures,includingmankind'snearest cousinschimpanzees) toAfro-texturedhairor"unusual"(i.e.firmlylooped).Thiscontentionexpect that wavyhair betterobstructsthe entryof UV lightintothe bodyinrespectto straighthair (inthisway wavyor snakedhairwouldbe especiallyworthwhile forlight-cleanedprimateslivingatthe equator).It issubstantiatedbyIyengar's(1998) discoveriesthatUV lightcan go intostraighthumanhair roots (and inthismannerintothe bodythroughthe skin) bymeansof the hairshaft.In particular,the aftereffects of thatstudypropose that thismarvel lookslike the sectionof lightthroughfiberoptictubes(which don't workas adequatelywhencrimpedorpointedlybendedorwound).Inthissense,whenprimates (i.e.HomoErectus) were progressivelylosingtheirstraightbodyhairandin thiswayuncoveringthe at firstfairskinunderneaththeirhide tothe sun,straighthairwouldhave beenaversatile risk.Byconverse rationale,later,aspeople voyagedmore remote fromAfricaand/orthe equator,straighthairmayhave (at first) advancedtohelpthe sectionof UV lightintothe bodyamidthe move fromdim, UV-ensured skinto palerskin.AndForeverykindof hairthere isa best chi flat iron.

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  • 1. Additional data:Humantransformativehereditaryqualities Surface Wavy hair Man withwavyhair(DavidLuiz) Jablonski attestsheadhairwasdevelopmentallyprofitable forpre-peopletoholdsince itensuredthe scalpas theystrolleduprightinthe extreme African(tropical) UV light.Whilesome maycontendthat, by thisrationale,people oughttolikewise expressfurry shouldersinlightof the factthat these body parts wouldputativelybe presentedtocomparative conditions,the insurance of the head,the seatof the cerebrumthat empoweredhumankindtowindupa standoutamongstthe bestspeciesonthe planet(andwhichlikewiseisexceptionallypowerlessduringchildbirth) wasseeminglyamore dire issue (axillaryhairinthe underarmsandcrotch were additionallyheldasindicationsof sexualdevelopment). At some pointamidthe steadyprocessbywhichHomoerectusstarteda move fromfuzzyskinto the exposedskincommunicatedbyHomosapiens,haircompositionputativelystepbystepchangedfrom straighthair[citationneeded] (the state of mostwell evolvedcreatures,includingmankind'snearest cousinschimpanzees) toAfro-texturedhairor"unusual"(i.e.firmlylooped).Thiscontentionexpect that wavyhair betterobstructsthe entryof UV lightintothe bodyinrespectto straighthair (inthisway wavyor snakedhairwouldbe especiallyworthwhile forlight-cleanedprimateslivingatthe equator).It issubstantiatedbyIyengar's(1998) discoveriesthatUV lightcan go intostraighthumanhair roots (and inthismannerintothe bodythroughthe skin) bymeansof the hairshaft.In particular,the aftereffects of thatstudypropose that thismarvel lookslike the sectionof lightthroughfiberoptictubes(which don't workas adequatelywhencrimpedorpointedlybendedorwound).Inthissense,whenprimates (i.e.HomoErectus) were progressivelylosingtheirstraightbodyhairandin thiswayuncoveringthe at firstfairskinunderneaththeirhide tothe sun,straighthairwouldhave beenaversatile risk.Byconverse rationale,later,aspeople voyagedmore remote fromAfricaand/orthe equator,straighthairmayhave (at first) advancedtohelpthe sectionof UV lightintothe bodyamidthe move fromdim, UV-ensured skinto palerskin.AndForeverykindof hairthere isa best chi flat iron.