Somedesertanimalscansurvivethesummerheatanddrynessbecausetheyareveryunusual.Thecamelforexamplecanexperienceandbearanincreaseinthetemperatureofitsbodyanditsbloodof9twithoutanythingbadhappeningtoit.Inadditionitcandrinkalotofwateratonetime;thenstoreenoughwaterinpartsofitsbodytosupplyitsneedsfortwoweeksormore.Thekangarooratontheotherhandgetsallthewateritneedsfromwaterthatitpro?duceswhenitbreathes.Howevermostanimalsneedtomaintainafairlyconstantbodytemper?atureandwilldieifitrisesmorethan5^.Thereforetheyneedtofindsomewaytostayawayfromtheheatofthesummersun.Norcanmanyanimalseitherstoreorproducewaterintheirbodiesasthecamelandkangarooratcan.Sotheymustfindwaystokeeptheirbodiesfromlosingwaterbecauseoftheheat.

Becauseveryfewdesertanimalscansurvivethehightemperatureofatypicalsummerday，mostofthemareactiveonlyinthenight.Onlyafterthesunhassetdoesthedesertcomefullyto life.Thenightisrelativelycoolandthedarknessprovidesprotectionnotonlyfromthesunbutalsofromotheranimalsandfromthebirds.Sothecomingofdarknessisthesignalforthelargemajorityofanimalsandinsectstostartagaintheirsearchforwaterandfood.Whenmorn?ingcomes，mostofthemseekshelteragain：manygounderground;nearlyallfindsomedarkandcoolplacewheretheycankeepawayfromthesun'sheat.

Formanyspeciesofinsectslivinginthedesertiseasierthanforanimals.Likemanydes?ertplants，theyhaveawaterproofskinwhichpreventswaterlossbecauseofthehightempera?ture.Inadditionsomespeciesspendallormostoftheirlifebelowground.Hereformostoftheyearatleastthereissomemoistureanditisgenerallycoolerthanonthesurface.Inthecaseofants，onlyadultsleavetheundergroundnests，andtheydosoonlytogatherfoodortodefendthenestagainstattack.

( )1.Comparedwithotherdesertanimals，thecamelcanbear

A. averylowbodytemperature

B. onlyalittlechangeinbodytemperature

C. abigincreaseinbodytemperature

D. aconstantchangeinbodytemperature

( )2.Thekangarooratisdifferentfromotheranimalsinthat

A. itcanproducewaterthrough