7/28/2019 Endocrine disruptors can perturb development

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compounds lsoaffect he postnatilgrowthandmaturation fchildren, eading o cognitivedefects ndmental etardation.The environment affects normal develoDmentThe environrnent controls rnanyaspectsof normal animal development. he l:wae of cersin madne nvertebrates,or ex-anple,do notmetamorphosento adulauntil thevencounter'pecif ic.ur lacen uhich osenledosn. wirhplrnr j .aninralderelopmentsol ien nfluencedy rnrenction." iLh rher r -ganisns. or example,le smallwater leaDrrr",rwill change,r . r rorph', logl \ d.ubl,ng he izeof rhe .helma on Jetop of its headafter encountering predatoryly hna (fi$rre19.22). inallv, hen miceor zebrafish re eared ndergelm-Feecondiuons.he,r rL.arede\oid fbacrer ia rL nonnatt\colonize the gnt. Ar I result, there are defects n intestinal dif-ferentirtionand i'ncdon n bothspecies.A particularly clear example of environmentrl ef&cson dcvelopment is temperature-dependenr e\ determinatioD(TSD) In manl' reptiles,dre emperatureoftie soil in which theeggs ncubatederemines the sexof the hatchlinEs. n somesoe-cie,.on< er domnare. r inrermcdiateempeiarure...he;a"only the oppositesexdevelopsat ternperatures t either e(remeof dle nanrral thermal range. In other species, ne end of thenatural themal rangeusually producesall rnales,dre otier endof G, =ngeproduce.r l lemrle\. nd nremediareemperaruresare usuallv gender-neutal.One possible azard fTSD is that an ncreise n Elob:ltemperarure\a1erentual l l ke$sex rLio. n "i ld p"puta-r ion, of n,mJl,.