Therea rem il[ionso f differenst pecieos f animailn the world.S omea nimatsli,k et he bluew halea, rev eryb ig. Othersa res os mallt hatw e almosct an'ts eet hem. Thesea nimalsa ll havev eryd ifferenlti fe cycles. AnimaGl roups Scientists put animals into groups. The animals in each group are the same in many ways, and they often have very similar life cycles. The two biggest animal groups are invertebrates and vertebrates. ... - tailieumienphi.vn