«««« ORANGUTAN…TAXONOMY…AND…NOMENCLATURE« « Craig«D em itros« « The«taxonom y«of«the«orangutan«has«been«confusing«and«is«still«the«subject«of« m uch«debate.«Q uestions«at«the«specific«and«subspecific«level«are«still«being« investigated«(Courtenay«et«al.«1988).«The«follow ing«taxonom ic«inform ation«is« taken«prim arily«from «G roves,«1971.« « H IG H ER«LEVEL«TAXO N O M Y:« O rder:«Prim ates« Suborder:«A nthropoidea« Superfam ily:«H om inoidea« Fam ily:«Pongidae«(Includes«extant«genera«Pan,…Gorilla…and…Pongo).« « H ISTO RICA L«TAXO N O M Y«AT«TH E«G EN U S«A N D «G EN U S«SPECIES«LEVEL:«« G enus« Pongo«Lacepede,«1799.« O urangus«Zim m erm an,«1777«(N am e«invalidated).« « G enus«species«(Pongo…pygm aeus«H oppius,«1763).« Sim ia…pygm aeus«H oppius,«1763.««Type«locality«Sum atra.« Sim ia…satyrus«Linnaeus,«1766.« O urangus…outangus«Zim m erm an,«1777.« Pongo…borneo«Lacepede,«1799.««Type«locality«Borneo.« Sim ia…Agrais«Schreber,«1779.««Type«locality«Borneo.« Pongo…W urm bii«Tiedem ann,«1808.««Type«locality«Borneo.« Pongo…Abelii«Lesson,«1827.««Type«locality«Sum atra.« Sim ia…M orio«O w en,«1836.««Type«locality«Borneo.« Pithecus…bicolor«I.«G eoffroy,«1841.««Type«locality«Sum atra.« Sim ia…Gargantica«Pearson,«1841.««Type«locality«Sum atra.« Pithecus…brookei«Blyth,«1853.««Type«locality«Saraw ak.« Pithecus…ow enii«Blyth,«1853.««Type«locality«Saraw ak.« Pithecus…curtus«Blyth,«1855.««Type«locality«Saraw ak.« Satyrus…Knekias«M eyer,«1856.««Type«locality«Borneo.« Pithecus…W allichii«G ray,«1870.««Type«locality«Borneo.« Pithecus…sum atranus«Selenka,«1896.««Type«locality«Sum atra.« Pongo…pygm aeus«Rothschild,«1904.««First«use«of«this«com bination.« Ptihecus…w allacei«Elliot,«1913.««Type«locality«Borneo.« « CURRENT…TAXONOMY« « The«current«and«m ost«accepted«taxonom y«of«the«G enus«Pongo«includes«one« species«Pongo…pygm aeus«and«tw o«subspecies«P.p.…pygm aeus«(the«Bornean« subspecies)«and«P.p.…abelii«(the«Sum atran«subspecies)«(Bem m el«1968;«Jones« 1969;«G roves«1971;«Jacobshagen«1979;«Seuarez«et«al.«1979«and«G roves«1993).« 5« « . lthough«hybrids«have«been«produced«in«captivity,«A ndrew s«(1984),«G roves« (1986)«and«Janczew ski,«G oldm an«and«O 'Brien«(1990)«have«suggested«that«the« degree«of«difference«betw een«the«tw o«subspecies«is«considerable«enough«that« the«tw o«form s«be«considered«separate«species.«Based«on«further«investigation« of«the«physical«appearance,«behavior,«m orphology«and«biochem ical«and« chrom osom al«characteristics«of«the«subspecies,«the«authors«concluded«that«the« range«of«variation«does«not«w arrant«separate«species«designation.««They«concur« on«the«subspecific«taxonom y«of«Pongo…pygm aeus…pygm aeus«and«Pongo… pygm aeus…abelii.… « Recent«m olecular«genetic«research«results«show «a«distinctive«difference« betw een«the«Bornean«and«Sum atran«populations«different«enough«from «one« another«to«w arrant«separate«species«classification«(See«O rangutan«G enetic« D iversity«Chapter,«this«volum e).««« « Rohrer¼Ertl«(1988)«suggests«an«alternative«taxonom y«for«the«orangutan:«G enus« Pongo«von«W urm b,«1784«and«species«satyrus«Linnaeus,«1758.« « H e«divides«the«species«Pongo…satyrus«into«three«subspecies:« Pongo…satyrus…satyrus,«the«recent«Sum atran«subspecies«and«Sum atran«and« Javan«fossil«and«subfossil«form s,«Pongo…satyrus…borneensis,«the«recent«and« subfossil«Bornean«subspecies«and« Pongo…satyrus…w eidenreichii,«fossil«and«subfossil«form s«from «China,«Loas«and« Vietnam .«««« « PH YSICAL…APPEARANCE…AND…DESCRIPTION…OF…TH E…TW O…ORANGUTAN… SUBSPECIES« « The«tw o«subspecies«of«orangutan«exhibit«a«broad«range«of«variation«in« phenotypic«characteristics«(Rohrer¼Ertl«1988).««The«physical«differences«are« m ost«apparent«in«adult«m ales.««Perkins«and«M aple«(1990)«state«that«the« determ ination«of«subspecies«based«on«physical«appearance«alone«is«im precise.«« Subspecies«identification«has«been«refined«by«karyotyping«and«genetic« analysis.««The«diverse«physical«characteristics«used«to«differentiate«the«tw o« subspecies«are«listed«below .« « 6« «« Table…1… … Physical…Characteristics…of…the…Tw o…Orangutan…Subspecies… … Pongo…pygm aeus…pygm aeus……… Pongo…pygm aeus…abelii… (Bornean«subspecies)«« (Sum atran«subspecies)« « « hair…color… hair…color… darker,«alm ost«m aroon«(A)« lighter,«m ore«cinnam on«colored«(A)… vary«from «red«rust«to«dark«m aroon«or«blackish«brow n« light«rusty«red«or«reddish«cinnam on«(B,E)… (D ,E)« young«are«paler«orange«becom ing«cinnam on«w ith«age«(C)… young«have«bright«orange«hair«w hich«darkens«to« chocolate«or«m aroon«w ith«age«(C)« m ay«have«w hite«or«yellow «hair«on«face,«in«beard«or«groin« (C,«D )… never«have«w hite«hairs«(D )« pelage«a«m ixture«of«light«and«dark«hairs««(C)… m ore«uniform «dark«pelage«(C)« m ore«variation«in«color«(E)« less«variation«in«color«(E)« « « « hair…length… hair…length… less«hair«about«the«head«density«and«neck«(A)« m ore«hair«about«the«head«and«neck«(A)« young«thinly«haired«(A)« young«have«denser«hair««(A)« shorter«hair«overall«(C)« longer«hair,«infants«have«long«hair«on«top«of«head;«adult« m ales«have«long«hair«on«arm s,«sides«of«back«and«beard«(C)« « « « « hair…texture… hair…texture… hair«stiff,«shiny«and«brittle«(C)« hair«is«finer«and«fleecier«(C,D )« stiffer«and«shinier«(D )« dry«in«texture«(D )« « « hair…pattern… hair…pattern… no«inform ation« short«hair«com es«on«head«forw ard«over«top«of«head«(D )« … … 7« Pongo…pygm aeus…pygm aeus……… Pongo…pygm aeus…abelii… (Bornean«subspecies)«« (Sum atran«subspecies)« « … facial…hair……… facial…hair……… beard«is«less«noticeable«(A,«E)«« beard«is«alw ays«present«and«w ell«developed«(A,B,E)« less«hair«about«the«face«(C)« beard«is«lush,«often«gives«a«m ustached«« appearance«(A,E)«««««« in«young«face«is«usually«bare«(A)«««««««««««««««««««««««« fem ales«also«have«long«beards«(A)« beard«is«darker,«from «orange«to«dark«red«(C)«« both«sexes«generally«hairier«about«the«face«(C)« facial«hair«has«rough«tousled«appearance«(C)««««««««« young«are«hairier«about«the«face«(A)« facial«hair«generally«short,«scruffy«and«less«noticeable«(D )«« m ales«m ay«have«long«pointed«or«double«pointed«yellow « « or«orange«beards«(C)« « facial«hair«neater«in«appearance«(C)« « both«sexes«have«longer«facial«hair«(D )« « long«yellow «beard«grow s«out«of«upper«jaw «giving«a« « m ustached«appearance«(A,D ,E)««««««««««««««« « … shape…of…face…………………… shape…of…face…………………… broader«faced«w ith«prom inent«m uzzle«but«have«a«great« m ore«elongated«and«flat«w ith«a«definite«O ¼shape«(B)« deal«of«variation«(C)« jaw «is«less«pronounced«(A)« upper«and«low er«jaw s«are«pronounced««« (prognathous)««(A,D )« long«oval«face«w ith««m arked«cheek«hallow s«(C,D )« « figure«eight¼shaped«face«(D )«««« « « « facial…color… facial…color… area«about«the«eyes«has«a«bluish«cast««(A,F)« face«grey«(F)« … « eye…color…………… eye…color…………… darker«eye«color«(A)« usually«clearer«and«(variable)«paler««(A,D )« … « 8« … … Pongo…pygm aeus…pygm aeus……… Pongo…pygm aeus…abelii… (Bornean«subspecies)«« (Sum atran«subspecies)« « « look…or…appearance…………… look…or…appearance…………… in«adult«m ales«"unfriendly«glow er"«(D )««««««««««««««««« in«adult«m ales«"haughty«quizzical"«look«(D )« « « eye/nose…angle……(i.e.…angle…betw een…center…of…eyes… eye/nose…angle……(i.e.…angle…betw een…center…of…eyes…and… and…center…of…nasal…septum )…(E)… center…of…nasal…septum )…(E)… in«adult«m ales«angle«is«48¼66«degrees,«« in«adult«m ales«angle«is«37¼51«degrees,«« m ean«57«degrees««(C)« m ean«45«degrees««(C)«« « « cheek…pad/flange…(the…one…character…in…w hich…a…very… cheek…pad/flange…(the…one…character…in…w hich…a…very… clear…difference…appears…to…exist…betw een…the…tw o… clear…difference…appears…to…exist…betw een…the…tw o… subspecies…(E)… subspecies…(E)… in«m ales«developm ent«starts«in«8th«year,fully«developed« in«m ales«developm ent,«sarts«in«10th«year,«ully«developed« by«15th«year«(A,E,F)« by«20th«ear«(A,D ,E,F)… naked«or«covered«w ith«short,«bristly«hairs,««is«quite«shiny« hair«on«pad«is«light«in«color,«very«noticeable«and«silky«(A)« (A)««««««««««« … skin«is«dark«brow n«or«black,«naked«or«has««sparse«red«hair« have«tufts«of«short«w hite«or«yellow «hair)«(plum ous)«(C)« (C))« … curve«outw ard«from «the«face«(A,E)« rest«flat«against«the«face«(A,E)« sw ing«forw ard«like«"blinkers",«appear«rounded«and« extend«laterally,«parallel«to«the«face,«gives«the«face«a« lum py«(C)« diam ond«shaped«appearance«(C)« heavier«and«less«rigid,«develop«laterally«from «both«top« … and«sides«of«face,«giving«a«square«appearance«(C)«« *Pad/flange…developm ent…in…a…subordinate…m ale…m ay…be… junction«of«the«pads«above«the«brow «results«in«a«deep« inhibited…by…the…presence…of…a…m ore…dom inant…m ale…(Kingsley… w rinkled«pad«(C)« 1982;…N acey₣M aggioncalda…and…Czekala…this…volum e).… throat/gular…pouch………………………… throat/gular…pouch………………………… large«and«pendulous««in«adult«m ales«(A,D ,E)«« less«noticeable«in«adult«m ales«(A,D ,E)« larger«and«generally«naked«(C)« sm aller«and«usually«hairy«(C,F)« « « … « « « Pongo…pygm aeus…pygm aeus……… Pongo…pygm aeus…abelii… (Bornean«subspecies)«« (Sum atran«subspecies)« body…size/«build………………………… body…size/«build………………………« tendency«to«becom e«obese«in«captivity«(A,E)«« larger«in«body«length,«appears«m ore«m uscular,«rarely« becom es«overw eight«(A,E)« robust,«often«obese«(C)… thinner,«lankier,«tend«to«be«m ore«m uscular«or«linear«in« … build«(C,F)« Body…W eight… Body…W eight… Inform ation«on«body«w eights«is«scarce«(E).« Inform ation«on«body«w eights«is«scarce«(E).« « « Presence…of…nail…………………………… Presence…of…nail…………………………… nail«m ay«be«m issing«from «hallux«(A)« see«inform ation«below «from «Rijksen«(1978)« « « foot…placem ent/locom