TherehasbeenlifeonEarthforaround3.5billionyears.Thefirstmicroscopicsingle-celledorganismsresidedintheworld’soceansandgraduallydevelopedintocomplex,multicellularorganisms,fromdinosaursinthebeginningtomammalsasweknowthemtoday.Thiswasaresultofevolution,whichisdrivenbynaturalselection:onlylivingthingsthatsuccessfullyadapttotheirenvironmentwillsurvive.
更新时间:2022-11-17 直链:www.optocc.com