鳄鱼：

　　Crocodiliawelwitschiales(all)ofreptiles.Usuallythemassive,heavyamphibians,appearanceandlizardsslightlysimilar,belongtocarnivores.Palatalpowerful,longconicalteeth,therearemanyshortlegs,claws,aweb.Tailislongandthickthick,withscales.Nowabout20varietiesofcrocodiles.

　　Thereasonisbecauseofitsspecialattentionintheevolutionhistoryoftheexistingstatus,biologicalandcrocodilesareprehistoricdinosaurreptilesisthelastlinkcombined.Atthesametime,thealligatorisabirdofexistingrecentlyblood.Variousalligatorfossilshavebeenfound,4mysticetesinthreehavegoneextinct.Accordingtothesebroadfossilrecord,mayestablishalligatorandothervertebratesclearrelationshipbetween.

　　乌龟：

　　Thetortoisegenerallifeinriversandlakesandswamps,reservoirandhill,sometimesashore.Inthenaturalenvironment,thetortoisewithworms,screw,shrimpandfeedonfisheatplants,thestem.Thetortoiseisavariabletemperatureinwinter,animals,orwhenthetemperatureisalong-termlowcircumstances,thetortoiseintohibernation,varioustypesoftortoise,begantohibernatetemperatureisnotidenticalalso,butusuallyin1015degreesCelsius.Thetortoiseshellinlong-termwillalmostnoactivitiesandbreathingit,hypothermia,bloodcirculationandmetabolismslowsdown,thespeedofnutrientsandconsumeless.Thiskindofstateandsleep,butitisasimilarforseveralmonthsofdeepsleep,andevenamildparalysis.

　　袋鼠：

　　KangaroosareindigenousonlyAustralianmainlandandpartsofPapuaNewGuinea.Amongthem,somespeciesforAustralia.AllAustraliankangaroo,zooandwildzooexceptinthefield,life.DifferentkindsofkangarooinAustralia,differentkindsofnaturalenvironmentoflife,fromthecoolclimateforestsanddesertplainstothetropicalregion.

　　Thekangarooisherbivores,eatmanyplants,somestilleatfungi.Mostoftheminthenight,buttherearealsosomeactivitiesinthemorningoreveningactivities.Differentkindsofkangarooindifferentkindsofnaturalenvironment.Forexample,moreLloydnesttokangarooandtreekangarooliveinthebushes.Akangaroolikeabigrockcrack,cavesandashelter.