. ▁Over ▁ 5 2 % ▁of ▁the ▁bird ▁species ▁found ▁in ▁Mexico ▁live ▁in ▁the ▁state , ▁with ▁ 5 2 5 , ▁ 4 0 % ▁of ▁Mexico ' s ▁m amm als ▁with ▁ 1 7 3 ▁and ▁ 1 8 % ▁of ▁its ▁re pt ile ▁species . ▁There ▁are ▁also ▁ 7 , 5 0 0 ▁species ▁of ▁ve ined ▁plants . ▁One ▁reason ▁for ▁its ▁b iod iversity ▁is ▁that ▁is ▁lies ▁in ▁the ▁transition ▁area ▁between ▁the ▁temper ate ▁north ▁and ▁tropical ▁south . ▁It ▁also ▁lies ▁at ▁the ▁northern ▁edge ▁of ▁the ▁Sierra ▁Mad re ▁del ▁Sur ▁and ▁is ▁on ▁the ▁Trans - M ex ican ▁Vol can ic ▁B elt , ▁which ▁provides ▁a ▁wide ▁variety ▁of ▁e colog ical ▁conditions ▁from ▁tropical ▁rain for est ▁conditions ▁to ▁semi ▁ar id ▁areas ▁to ▁areas ▁apt ▁for ▁con ifer ▁for ests . ▁ ▁Its ▁five ▁natural ▁regions ▁are : ▁North western ▁Pla ins ▁and ▁S ier ras , ▁Sierra ▁Mad re ▁Occ ident al , ▁Central ▁Pl ate au , ▁Trans - M ex ican ▁Vol can ic ▁B elt , ▁which ▁covers ▁most ▁of ▁the ▁state , ▁and ▁the ▁Sierra ▁Mad re ▁del ▁Sur . ▁It ▁has ▁an ▁average ▁alt itude ▁of ▁ ▁M AS L , ▁but ▁ranges ▁from ▁. ▁Most ▁of ▁the ▁territory ▁is ▁semi - flat ▁between ▁, ▁followed ▁by ▁rug ged ▁terrain ▁of ▁between ▁ ▁and ▁a ▁small ▁percentage ▁of ▁flat ▁lands ▁between ▁. ▁Princi ple ▁elev ations ▁include ▁the