NEWS 108 E - page 36

NEWS108
36
Thenamesused for cultivated formsarevery fanciful: this is theBloodSandfire.
BeardedAgamas sometimes threatena lot,butonlyvery rarelybite.
Tricolor cultivated form, ”Rainbow”.
Thecutefactor
Itsundemandingnatureand tamenesswere
certainly important factors in the triumphal
progress of theBeardedAgama throughthe
terrariumsof theworld.After all, theBearded
Agama is thought tobe the reptilemost fre-
quently tradedall over theworld! But aplea-
singappearanceisalso important.AndtheBe-
ardedAgamaoffersthat inseveral respects.
Firstly,theBeardedAgama-zoologicallyspea-
king”the”BeardedAgamabelongstothespe-
cies
Pogonavitticeps
-hasthebroadestheadof
allPogonaspecies.Thismakesjuvenilesinpar-
ticular look particularly charming to us hu-
mans.Creatureswith largeheads instinctively
awakenprotectiveurges inushumans.This is
probablyadecisive reasonwhyof the remai-
ning sevenPogona species,only
P.henrylaw-
soni
has achieved any degree of terrarium-
hobbyimportance;theotherspeciesaremain-
tainedonlybyspecialists.
Widelydistributedandrich invariants
In thewild theBeardedAgama isdistributed
over a largepartof thedesert regionsof ea-
sterncentralAustralia(NewSouthWales,Nort-
hernTerritory,Queensland,SouthAustralia,Vic-
toria).It isconsideredcompletelyunendange-
red in thewildand isn't includedon the IUCN
RedList.
Not surprisingly,within thishugedistribution
regiontherearelocaldifferencesintheappea-
ranceof thepopulations.Witten&Coventry
(1990)studiedadwarfpopulationfromtheBig
Desert(Victoria),butfoundthatapartfromthe
fact that these specimens attained a head-
body lengthofatmostonly17.5cm(asoppo-
sedto25cm intheotherpopulationsstudied
todate),therewereno significantdifferences
thatwould justifyerectingaseparatesubspe-
ciesorevenspecies.
Butawidedistribution isalmostalwaysapre-
requisite foracompletelydifferentphenome-
non:theoccurrenceofcultivatedforms.Asthe
crossing of individuals fromdifferentpopula-
tionsthatneverencounteroneanother inthe
wildleadsrelativelyquicklytogenetic patterns
thatmanifest externally, including incolora-
tion forexample.Ifsuchspeciallycoloredspe-
cimens are then bred together deliberately
thentheresult iscultivated forms likethose il-
lustratingthisarticle.
Inbreeding-aproblem?
The term "inbreeding" always has negative
connotations foramateurbreeders.This isbe-
cause among humans very close relatives
shouldn'thavechildren togetheras there isa
dangerofgenetically-induceddeformitiesor
illnesses resulting.But this isofnoconcern in
animal breeding.Without close inbreeding
therewouldn'tbea singledomestic formof
animal,ienodogs,nocats,nocattle,sheep,or
horses,no chickens,andnoBeardedAgama
color forms.TheBeardedAgamacolor forms
areessentiallyjustashealthyandfitforsurvival
astheirwild-coloredandwild-livingcousins.
Bewareofoverbreeding
Youshould,however,besuspicious ifBearded
Agamasare offeredatknock-downprices.The
reproductive rateof BeardedAgamas isvery
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