510 A, GARMFSTANI E"I AL,

sHool, C. R., C. A. RUC@$GTEL. AND N B. THovP-soN, 1985. sea tunles h rhe @rhedr UniteStates: nesting activity d deriled fbm adial and8loud suneys, 1982. He.petologi@ 41252-259.

srA!.w. S. F" AND I. P Ro6s. 1s78. An eatysB orend from gted tu.de msting beadEs m As@-sion Island. Copeia 1978:9H9.

Srarrsncal SoENcEs, 1993. $PLUS User! Manual.Statsci, Seattle Vlh6hingtd,

smNEBr lll& D L./ aM J. I. &cHARDsrN. 1981. Ob-

emtiG d the role of tanpaature in loggdlEadturue rest site slectid. Copeia798t233-247,

VENABGS, v[ N, AND B. D RFiEy. 194. Ilrodm AD-plied Statistics with tPLIJS, Srnrger-Verras, NddVork.

wmoRE C. P" AND P H. DurroN. 1985. InIatilirydbryonic mortality dd nesrsite Eele.tion inleathe$ack (De@lrlyr .o/id.a) dd gffi seaturtl€ (Creiorid uyda) in Surind. Biol. Co@nu:25t-272.

lowing may .onsbain the elabolation of sexu,ally dimorphic body sizes or structues (e9.,Gans, 196& 1978j AndrewE et al., 1982 Henle1989; Gill et al., 193). If such constrahts areimpodant, we might expect to s€e that the in-dependent e\,rolution of lossoriality in diveE€squamate lheages wdnd be accompanied byconsistot modficati(N oI other eoloqiolbaits as we[.

In order !o teEt this hwothesis. w€ reauiredetailed data on t}le eco6;cal aftributes oifossorial squarnares oI a wide vdiety of phytoge-

toldJ,r&4b,.4 \hr 14. il| 4. oa 510 516..2000cop] nshi 2000 tiieh fr rhc studi bf Amph'i aN md Repbte!

Li{e Underground: Food Habits and Reproductive Biology of TWoAmphisbaenian Species from Southem Africa

JoNATHAN K. WEBB,U IICHARD SHTNE 2 WIuAM R. BRANCH,3 AN'D PETER S. HARLow,

'Sch.ol of Biolagiel nnd Etuivwntal SciM, Notthdk'tirtito/y Unimtit!, Ddt@in, NI 0g'g, Aa,totid. E-nail:i _axbb@,ite. I t u. e d!, tu

,sch'ot oJ BioloSicdl sci46 A)8,'fit ufliMsiry ol syd^ey, Nsw 2006, A6ttutia, and3Departtunt of Hetpetalov Pott Etizabeth Mu*uh, P.a Bd 13147, Hu@od, papubtic of Sauth Ahi.n

ABsrMcr.-&din.rion and disse.tion of 216 musom sp€.imen. of rwo spe.i6 of.mphi6baenids (theshovel€nouteil Mtup.tfis a a.hiat@ and mtnA-heaaea Tasdstis qtadtil@sl t@ sdtqm AJri.a prcvideddala on morphology, sdul .limorphism, rprcdu.tio4.nd dierary hibft$ The two spe.ies ilifierd osid-eDbly in absolu6e oize, in body prcpoltions (eg, head wialth etative ro snour-vent length) dd in rhe degEcof s@l dinorphism in th6e inii& In the rclarively he a\"t-bod\.d Mdoteltis bo]J:, seG artained sihildbody l€n8ths, bul femles had wider heads than @nspeciic md6 Conv6elt in rhe thin-bo.tieat Zryaaspls,f4rl€s atl.ined larger bo.ly sizes thd .ospecifi. nal6, d<l theE was @ s*al dinorphisn ; headsize Clut h siz6 werc sm.ll in both spai6 (mens of 2.4 ndatet ij t1lo,@petti6, 3,3 eW in 4EaspBtdd w@ nor @ftl.teal with frtten.l boily size Temires wet the mosr .omon prcy for borh rda, bda wide varie9 of other soft-bodied invertebrates (beefle lar.e carereitlas) ws .tuo <oE@ed. The rwospeciee .liffereal in tlietary .omposition, mean prcy size, tud in rle ruhbeE of pret ile@ per 3tomachStmrahs of M@p?rts qlained noE pEy it€ms lhan slomch6 of Zgaajlt! (meds oI722 v€FG 13.0pey itemst dd prey ing6t€ d by Monorybnt w@ t*aet t\^n those 6t Zlg6pis. In Mdoperf,s�, rh€E was asi8ni6.dt positive corelation betwe€n prcdator size dit pEy number, bur larEer tiards @tin@d ro feedon rcl.tiv.ly small pEy. nre evese patlem was foud in 4aasll, The substelial differcnces in trcphi.biology betw€en these two taa and orher synpakic (6so!ial rptiles, su88est that adaptntio* ro fo6so.iiitydo not @stdin ecotogi.al diveBity w hin buruwinS squmaret

Mary fossorial squaDate lineage disptayconvergst modiE@tions tlEt involve bodilrelmSatiorr limb reductior\ and chagee to heaistructue rhat pmir efficidt brEd{ins {eeGrs, 199r identified 62 such rransirioBi Su;hnodificatios mi8ht cororrain oths aspects ofan orgaism's bioLogy; for ermptq a hiad Lllarrs ernoerlt ar bLfrowins may be tess abte ro hdFdle larg€ prey itns, oirhe biomechanica of bu-

' . CoG?onding Autho

AFRICAN AMP}trSBAENIANS 511

netjc lineaSs. Anphisbasiac erhjbil d su ep.l T.I,fd9s'.!d adaprarions ro a bffiowihrlJesryle mdudin8 liDb-toss (in aI but one s+nus), amulat€d body, rduced eves, and an L_tr€nely modiffed head (eg., c;ns, 1968, 1928,1990). AIthdSh anpnisbain;as are aiscituLeawroery hrouShout the rropics, most av€itabtecrab on their biotogy derive from brief conFmenrs in taxorcmic rrearises. Reenl detaitedstudies de begiming bo renedy rhiq deficien(y(e9., Busad\ 1978j lvlartin er;t., lq90; Loo.,dd.Marrin t994j Lopez et al., 19981, atahtuShmost or thece ue concemed wrth a sinp,e sDe-cies. Blants .iMPu.

Despite the recenr inrerecr in anphisbaenirrbioloAy-, (ompd rah vely title is Lnoh; alour thenatur< tustory or AJrican specjes (e.g. vlsso,196Z Broddley el al.. IqTb; eanc dd"KJaHaq19891. We .hrdied hvo represoldrive species ofsthem African mphjsb,eniaJE Th; Idpuspecies. MonoppLtis a ri?i r. Arow, lo 35 on"inbody lsglh dd i. disrributeA m morst.avaruohabitats ir northm Nmibia and Lhe Caprivistflp plus adjacent parts of Boswar and arL_gola (B%ndr Iq98). lle head is hjaht\ modifiedfor bunNing. wirh a showl-sha;ed snoul. h,conftast. Tygo'pis quannkns t"err�! Uoadtndd Broadley, 1q97, is s;alter (ro 2J cmr, wi[Ld rouded snour. This specie5 h6 a brodder distribudon than M. ,etttae; rhe Lwo species d.s,'rnpakic ol.€ much of fie ranze o(

'M. othr-

rM. but Z. qhdnnh$ e\thds *roush the r.ala-harj from the NorihemCape loZai; &d atonethe Limpopo njrer ro Mozambique rB;Ji1998). Thuq. jt ocrupies drier habjt;B fian doesute rdger speoes. Here wp plovide orisinaldatdm the natual hstory of rhese rwo dDhisba_enian specj$ of souf'em Afncd bas€d on *_anination oI prc5erued spftjmea in museM

M^TERrAts AND MErHoDsWe €rmined all presqved specjmens of M

awhEl@ (N - 68\ td Z. quadnions lN - t48tln the coUections of the Tr.trltal Museum tpre'toria South Afri.a), rhe port fLi2abelh Museru{Edlem Capq S@th AJrica). the Srak Museunor Namibia dd the Dircctorare of Wildlife Con-s€I!?tion Ooth in Windhoel, Nmibia L For eachsjtecimJn we measured snouFvent tensrh(nencerorttr Sw) and tait lenSth wjth a rujer\@ tne nearesr mn} For speomens in eood con_drh.n or those .cmtaining pre1,, in sb;a<hs. weneasuled head width Lever with rhe @s.mouth width ar the rer-most part oI moirth_and.mid-body diameher (with vlmier cajiDers.@ tne neiuesr 0.1 mm). Eaci specimen'wsoP€ned with a mid-vmrral jncision so we coddqamme the gonads ed alimentarv rract. Oucntefia fd seruat mahrty h€re

-as fottows:

r,nil:s e{arggd htsid restes and/or opaque,Lnrc(ened e|erenl ducrsj femaleg rhictinedmuscnlff oviducts, vireltoeenjc (Mrid fouidpqad/or -@idurral "gs". F,"y it*i *;;:moved lrom the dtimotrry lrad dnd placed invials ror ldttr ideDrificarion. For eadr simpte ofprq' rt@s, we re(orded the IoINins: prev td;_on lo the ordinal level (whtre possibt;l; thd tohlnmber ofeach n''mphal6raS; ofprey iren (i.e.,adunr eg8!. t"an'ae pupae); *'e jenqrh and ma_,mD didmeter of rhe Iarqesr and smaltesr Dr*ilemi sd the lensthi dd-diam"re,s of Ge';;emost frequmtly ingesred prey ftems.

REsrrLrs

. t,totphrbgy.- Table I provides dara on medDody sizes ad morphotoSy oI ddutt mphjs_bamans. r4o4opdr; i._(onsidtrably targer lianzyS$pis, ad rs nore hea\ry_bodred. Mororptr,se\ceeded ZyBarpE in med djmensiorl! ldr alttraiis that w€ measue4 md the desree of se^udl,sra dimorplu(m also diJrered signjfiGntl).both se\es anaird similar body siz;c in Mo,,opdr6. but femaie 7lgaryis g9w signjfic{ryrdSer rhan drd coNpecific najes (l"abte 1). Llboth specier. males mahued ,l smdlter bod)size. than females (Iable l). We e\eined se\_ual dimorphism in orher kairs Oead w'dtt,,Dourh width. mid-body diameter) retarjve tubody len8lh usinS one fador ANcovAs {wjthse\ as the rrcror dd S\,1_ ds rlF cowiate). seL_ual dimorphism in rhe* hairs was absint inTuga'pts. but in Motup?his rhe slopes of rhe rr_ldtjonshjp befween S\.t ad IIW diuered be_tween the se\es (F, .. -- 7.30, p ,. 0.0t) at ldq.sVL females had wider heaas tlun ad mates"of

_Reprctlu.t iu Biotog!.-One temate ZvRosp,s( r ransqal Museum + 43J2t .olected 5lm;ry1974) contained iwo shelled oviductatesss (21.5'

?.9 .. .- size). indicatins ovipaii-"ty. wecoulo no( delerminp reproductive mode forMorrldrb. il is fikely ro bi vivipdolls, as is the(ongeneric M. .appnsis \Btoddtey er at-, 1926,.tras€d m cosrs of enldSed owian fotLjcte..both speciFs produced smatl (turches (for Mrr_opelti., (En littt stze - 2.4 range I 5, N - 5Dr zyJ4ry's, mea dutch size = 3.3. ranse l_jN - t2). Ba,ed on |n" .,i,n-* ;;; 3i ;,;:rrued spedmar, offsprin8 we.e tdee ret;i{vero maremar Dody lrze (minimum S,l|iL ofc4 vsa mem SVL of 2s2 mm Ior adulr femate Moropcltist 75 vs. fta n\n fot Zyparp6). SamDle sizeswere .mal, bur revealed no increce in cturcLsre wrh rutenat SVL in either sDecies (IorMorcpeltis t = -0.62, N = 5, p = 0.i6; for 2vp.a?'s r = 0.O5, N = ILp = o.az!,

Di, tary Habits.-Most amphisbafrianE con_tained prey in aheir sromaars. Uut the oro"".tion of amphisbaenians wth emp& stimichs

e . Eg e

o x

E

t g

is

B

€g

6 6

E g

E S

< €

6 3

. 9 5n f r

E ;

6 9 )9 5

I-E,!

&

E

Fi*s

4 r . ^ ^ ^1 . 1 9 1 : o i o o d 4q 4 s J J 4 i { i 4g : F l - j d . i d ! r 4

= - 9 * o e o o o 4" q d s J i 4 i . : J q3 : R n j d i j ^ + 6

F . e : - = - e .d E a l 9 j : J 3 o r 1 a: * e r i 4 ; + ! 4

3a 5 .e :s : i :^ q 3 ? d < " - . . : 4 1 d

9 - 1 i

g f? p: f; f$F; dEJgE9E :E

J, K. WEBB EI AL.

diff€red int€rsp€cfically (13 of 68 llaapeltbstomads and 48 of 1ag ZygbTir stomadu were€mpty, x, = 4.08, 1 dt P = 0.&). In lizards,sdlric diAestion of ins€cts is rapid {18,20 h ar22 C, Knowltorl 1936j Avery, 1973), ;o that theptobability of mounterine a lizdd with foodin r]re sto;adr w r dep€ni on how freouentlvit feeds. If *e sme that amphisbmniirrs re.tain some food in the storud tfie day fo owinstuedins, then we cd calculate the fiequencv oifeeding froin the proportion "f li-ids ,i'ithprey in stomachs. The high proportion of ^{oropelLis (73.5%t dd ZJSdspr; (65.5./") with food irstomd's sugg$ts dut borh species leed fre-guen0y, at leat twice pe. week, We Miredtie se;sonality of feeaing in ZygaspE, whtdlwere collected ved-r()md in reasonable num-bqs. FiJty pe.c;nt of ZvsaspE colle€ted duhsthe coollr- rnon*s gueeugust; containedpFy_in stomadls. which indjcates that rlus spe-.oes reeos veaFrounct.

Nunben'and TfW of PreV.-We rccorded a to-tal of 5001 prey item from the alimentary tractsof amphisbaenians. We Iolnd no evidence ofsexual djtrde@s in pley type or nubq foreither sDecies. but stoirui:h; ;f Mod.ltis mn-rained aignificantly more prey items than didthose oI Zysaspis (or wom lizdds with prey insbobachs: ANOVA. Fr,, = 34.6, p < 0.0001;tlo,apeltis: mee = 72.2, SD = 9J.2, rmge I461 prey iteN. N = 50 stomadrs: ZvSapisimes = 1J.0, SD = 17.9, rmse I 90 prev iteN,N = 91 stomachsl.

Both species or mphisbaeniaru fed mos y ontemjtes (9406 of prey il€r's ror Monnpeltis,a.%tot Zyg6pi6), but a w:de wiefy of ot}te! inveFtebrate [ay.a w€re consmed as w€l ffable 2]StomadE oI both soecies contained mostlv Eoil-drellins invedebftler althosh a small pro-portion of Z/tarprs stomadts c;taired w'salsurface-acti!€ tda (e.8., .entipeder eatri8sisopods; see Table 2). AlSFuSh lermiles werenmericallv imeortant Drev itms for boli am.phisbamio spmies, a signficantly 1ol€ prcportion of Zyg$pb stmadls (53.0%) containedthis prey type compared to stobachs of A4oD+peltis $73% of Iall €romachs of contain€d ter-mites, x'� = r5.L I dt P < 0.0001, Table 2).

Pt y Ste.-Although they w€re coNumed inlow nurnbers, ldger pr€y items (such as cole-opteran and lepidopteran lal:@) undoultedlycompdsed a much higher proportion of the totalineested bioms for both sDecies of amDhb-bamians. The intelspecific A ftmc€ in preyt!'Des 16 also 6so&ted with a di66e6; i;ririan prey sizs. The prey items consuined bytulo,apeltis e)ere laryer rlw werc lhos€ tat€n byZygaspk (tor maximum l€ngtl, means of 16.5@sus 9.0 trD, Fla = 5.32, P = 0.03, for nari-mum dimeter, meais of 3.5 r€rsus 1-8 rnm;L*

ATRICAN AMPHISBAENIANS 513

TABE 2. CohPo8itim of the diet of the Alaicd afrphisbamiffi M. in hkt@ sA z. quadhjtd$, baed d@llsis of prey iteru frm the atimotary rrads or lss mru specinc. The tabre sirwJthe llmbq or€dr type or F€y item (N), peMtdEe of rhe rotat mmber oI prry ilft inSesred (',) and rhe frequdry otoNtu or eadr prey m 1E prcpo'rio of flphhbahi# Mraining Gr't prey rl?e). sampre siz6areslDM in pamthes. Nore rhdt the |abte h.ludes pFy ss lakd fiom ']re rcdum; ;(,U. anarr;c 1l s;aid z. qutd/ifns lN = 3).

(N = 5s) (N = 100)

94.2 47.3

29,1

1.81-8

*

7024 u.6

7,4

0.7

53.0

1.0

4,7

1.30.6

95

8

t239

8

17

16

12t2

761450,9

2.0

2 2

0.31.0

76

a2

1339

4I

33749

22.01.01.0

10.031,0

0.1

0.1

5.0

1 01,04.07.0

= 25.1 P < 0.001). \4ost prey items (includirslarse beetle lafte) had bien swaltowed whotEby amphisbaenians, md showed lftrle siFl ofmasticatior'" Th€ exception was adulr be;tles.whidr were found broken up inside the srom,

ach. Plots ol meth width vesus the diarnerqof the larqest prev item insested rcvealed thatanrphisbamiaris slected piv items whidr were*itler ttra" tt'"ir gape r"""'rig. r). Th" -.*drfiem@ betw€6 rna)jmu Dra diderer

- 1 0

6 6

g

6 2

!0

't J,:i.o 2 4 6 8 1 0 1 2

Mouth width (mm)

_ nc.Lt Relatimhip berF€o m@rh $idrhsnd rhe djdmctn of rhetdpestF(ev no n pested' M, an,hi2tL{&bd odet aftl z. qkd'rds (open cjrcles,. Thc dolred Irtr +ows ;he; p;"v diam;kr = ;@h widrh.,se urar m6t pr€y ibehs n8csted bv dphisbahid, @e sndller dun rheil g;pe

51,4 J. K. WEBB ET AL.

a: ,Ti:*.il,',*.,,tr;:,TY;;;g:T"dp,t $" 'p-"ch.or M cqan56. wtu* Brcad,ev ""dthLrs. trre diameters or Lte r".i;;i p*v,i#lj, ffi#;"Jl?#:"i p"l }rJi€steilermi,es

ft i,#.ql,ifi iir.ti!qi.":i"i:;ff '{T?d**;,rj"#;u"xnnrd:l;ili;#'"*lf lg,imfi,:t# #'ityr;sitl,iii"T" xfit tx;t:{mean.driferene - 3.s olm. SD - r.gs,. fi9y_ ablncr.arce or temites ir these d",s rdlhec thJnever, this duturmce was larselv due to

f*$l*:il,^zxr;:l"n:i"J::IdlF:nf :iJii*mru%?"y_,rff ffi h;,rtor._mou-trr riatrr as' iire -.;'"i;".

fij;ff_ ffffii"'l#jtr*i,*,,fl9ff"'*..i: :;frtrrlr,xi".':ilff ,i,njx,jril#:,'"*:3li x"ffi #h5'fr,T;trlxl.Tli#"i;1qdth dd mdimum prey djamerer wrs simi

f',"'.:#,:,T;:i i","ff:'i;;"r'j:;:;::";lill 15,::il;lfr:!1i'#1ilT,il;tJ[?J:,l!a)'"ria s,,i iiii"",/,"". ,_rn" *" "-_ :j"*l ;'J;:i*tTtr'i:#: ilw l*prxsbaeruar species showed stdkmelv differ(

llnt#"a.',:,$?ff :*'#,flil##l;#i+r,vlt:i,'H#"t.1j#fiTkll"iiYi'"*"':l';il9 fr?i.iJ:f :i,ru"l"; j;i'; ry on ,-arue Erdsec or ,ermi,es or ;t. icdbreru:yllT: 1118."j prey (correrd,ion\ r.*":'; *5 H:]'1"#c0;

Lopez et dL' rqqt: c;':-Ne,o

r;'d;i:il:,jq'i". ;'$jnHHX 5H.. rn'eresrinsrv re(or worr hac dem^n.rraLed

dmere, r -0,7. r ._:". p rbiqi'-iiJi lil1i"I#j:"1?#pniJf"";"ilff:iiPrey drametd, r = 012 N = 36 P = 0301 z!

rj: ::m*m:::jrffi d*ii#' ifftir,ff:lH:iiw::';"ljlir; n;.l:between womriza;d sh ;,a, .-,;_ "ilj ;il.i,|.#f :1,ffi:[;;l3:i:..:* n.iil9i'j;",3,]'; i ; #'i - t3:';v';:p ;dce (lea t ) noted-t#;""i"ir"l ii lili, o,,innimm prey rensrrr..r - oe:. ", - ,li'l' Ti:r;|li:6."tr"t"T1*X":"#fi,ilS3:u uur; rnmmm p.ey diamerer, r : 0.29. N::# g';';*Ts]#*;'lrui' ls* s*tili:". ;fr "#i ;li*":l ii;il ffi;::Try,#r:",r;r"ii"yrf iy" jgTi'#ffi thHr:*Hiii,",tr"}lr"rft *H

Db.u<sro\ ,rrrr a_rnptusr,asuff hdve relarively riirl, per_

^ff" *?.trx'fl"i"9"#'ii:'J.'ff f:' fiffi."[H::i"'ffi;iT%k! Ti:fl*rican amphisbaenie r, b-,dru;pp.;i;,""j_ H.,JIT ,t?i i**,,:f:i,.T:,:,;,S;1tr',{

ff *i1ffditlF:tu i.:T'ls.*::J:t: u"u ::; :l::I##sI;'S#*:r; :;ptuEbamjai's in orher parts of rhe world. Foe'*pre th*e rossoriar sq""_";;;;;;;i" ;: [:ff'lflLbTi,H":]""gTi5:J;:i:f,"ffi*:''trff,**8fl:??HtffiiY,:' ""o'a'"""i' "r p6t'mJrv ;;i*ll'ili,11i ill *"iree^cr rame ddte'*nir^ rc"u#j _i r;ri"i. trf J$ffitrf lf"iT,JIl] lilffijlit.i*i,"fff*$ir1i"...ry*."'il$.3'::Iffi .a:;*;rir$trnro;;nJli'l:lw€ preudsry been noted for rhe een;a MrD_ *r,_r" rr." -,-".r,-j,-i,i.:":_::11,1 l:,r

fl ifi#j6i{rff lrfr "iifl,"i;F:ry.5ff $ir::":;:"T::::_,.H"*j:ili":,ail,i,,:qffi ;?i:ttr"jg;yex.l$"*,,_?":u*"nr;::da^Lepdopteh (ta'we and pupae). De Waj{,e78) no,ed n-e.-s rarn ierirom,"_""-; H.llnffT.".:i "J.f*.lilfl

inlT,ll*;

ATRICAN AMPI IISBAXNIANS

predatoE thd the round-headed species. SDeafcals modifications of the head ior b"rri*-ing m;y preclude efdcimr hafldlin8 or inBesrionof larSe prey (Andiel!6 et al., 1987). Ou djetarydata support both of these hyporheses. Firsrll,the specj-arized tunower, tttlripenis, has a ds.atively narrow diei (five ta'ia), md larse ani.mals continue to fed on relahwlv smail DroLr conhrfast, the g€neratized b*";-, ZAiaspG.feeds on a wide rdSe of arduopod\ (eighttala) ircluding some surface-adive tar (cen.tipedes,.aLprpillars, isopods), and larger liard.fe€d on ldgd prey itms. Despite Lhe lendenc\'fot larger Tttgaspi> to irgesl larSer ad more d ivers€ prey. (U mlyseq of m@th size vqsu.prey diamets suSSesr tlut both .pecies ol mpNsbaeruds wde .rill resrricted to heding or.relatir€Ly narrow. elongate pret Thu.. diera4drf{ercnce. between MotuWItt dd Zvldspismight simply renect diffFrd(es jn prey;€ilab iry in dF difrerenr "adaptive zone!" (solt,?e and depth) o.opied by these two species,rrther than inteEDecifc diJferences in abilirv r..aptue md swalow prey

Brcmedrdicl .onstraints dssociated wirh un-der$ound locomotion (e.9.. Gac 1978) may,so place consbaints on the deqree of sevaldimorphism in body size dd sh+e in dphis.baenim. Our drta on sexual dnnorplusm in theAfrican dmphj\bamids (Tablc I) t68elher wfthleports of senaj dinorptusm in size and shaD€in other tda (cans ddRhodes, 1967; cii et;1..1993) mjtigate against this hForhesis In rh€or y other spdes studied in this respect (Biatrls.ftrreas), males haw longer heads tlm f€mdleswith the same body len8th (Busrcf, 1988, cjl etal., 1993). In the absence of detailed aurecolosi-cal studies, it is difficul. to intemrer rhe adiGti!€ significd@ of baits sudr c these. For &eple, larger head size in males thm in femalesb a wry common &ajt dons Uzards, dd hasgeneraily bes attributed to the action of serualplection (e8., Vitt dd Coope. 1985). Ir maynonetheless have coGequo€es for prev s€lec-tion (es., adult male BI;nu anereui e6: Iewer,IarSer prey thm do conspecific females; cil eta1.. 199J).

Fihalli, what do lu data reveal abNt the re-producti!€ mode of mphbbaenians? No derailsof reproduction in M. arcttiarc have Dreviouslvbeen-reoorted; ou data s"seest t}-i tfi.."J-cier lik; M. cryetrstr b tveuliang. Ou aata'onZ. 4ualiftot6 suooori fi^djmss oaBroadle andBroadtey (lgez),;ho reco,a& r"* 1No*i.ue.yand thrce (Ianuar"',) esqs ftom Moznmbique andZimbabwe z. quanions. rspectivelv. Theoret-ical dsmen6 sus;esr thad buoftnp saua-mates ihoUa Oe ovipuos. becase dis-rm;ionof dle body during tesktion nay impose highlocomotory costs in Favid vivipdous females

(Shine 1985). The evolution ol vivipdiiv wilhir,the Amphisba€nia, as wen m in oiher iossorialreptiles (e9, the scincid Iiads S.itrts, Soipho:,ard L?r6ta-Shine 1985) is not cotuistent widLthjs prediction. Reproductive outDut is a-lso ex-pectea to Ue low iue to the disidvantages ofbody disrension of reDroductive remale"(above). Mosl amphjsbddians le€m to Droducesmal titi€rs (o! alutches) of offspring ihat arelarge rclatil€ to the si? of the pms (e.A.,chtindia. one eg9. urophia, 2 4 egts, Loverid tqla4l; Broadley er al. 1q7b: I eptas?w. Z t)eggs, Gdq, li)zli tared et al., taqT: LttEndpea, t.2 embryos, Can5 and Krai<laq la89j l/o@relrr..ape,rir. i-3 embryor Vjsser. Icb7l. Low tecu-dity also dwacterizes many odDr fo5sorial rep-tiles, but thjs result 's conJouded bv rhe fdclslhat (l) mdy fossoriai tdd dp small (perhdp:(or biompcheical reasons) dd (2) smal speci;.of sqljdater (reSardless of rheir way of life)9?icaly produce small clut hes of relatirclylarge offspring (e.9., Fitd! 1970; Shin€ andGreer, 1991).

In conclusiorL available studies of amphisba-dians have .evedled conirderable inter.pecificdiversity in trophic biologla reprodudion, andsenal dimorphism, despire Ge very smdll pro-portion of <oecie\ Ior wfuch datd have been ob-iained. In 6rm of trophic biolo$, rhe mosrcon5islent fedture\ of amphisbaenim appear robe (r) a conenhation on invertebrates. esDecially laflal stases, and (2) a high feedins Ae.qumcy (tJT,icaut >60% of stomachs exdinedconLain prey: Cabrerd dd Merljni l9q0i Lopezet dl. 1o9li Cruz-Neto and Abe 1993i cil et altce3j present study). The high morphologicaldiversiry among livinS amphjsbamjans {intems oJ ol€Iail body proporrions dd head siztmd shape/ and th; irigh correldbon betwembodv fom and the "adaDti\€ zones" ocoDiedby these animals (GaE,'1968) offers a ulqueopporhnirv to test whether momholocical ad-a;ia6o$ t6 rossonaritv have beeri accoioaniedby consistdr modifi;tjotu of oLher ecoiosicatraits as e€ll. Ouantitauve tests of Lhis DroDo-sition shoutd be feasible bing the compirahremethod if we can obtain roUuir phytoginies torth€ gr@ps in question If the evolLrtion of fos-sonariry favoF particuid e.ologi(al shi(rs, orconshains qological diversit, then sudr non-random effe.ts should be detectable bv comDar-isons wiih appropriate outg.oup.. Cri' . L.igelscale the multiple *olutiona.y ori8irs oI fos-soriality in squaiEtes offer a rernaikable op-pmtlnitv to e).amirc the desree to whidr mio!;orphoiogicai adaptatioB

-Euy innuence tl\e

€volutionary trajectones of ecological tiaits.

AlkntukdgMk.-We rJ].ar\k W Haack€, M. crifii4and E. Griffin fo! allowing us to examire sp{imero

,. K. WEBB EI AL.

in tlei. ore ad S. Ritrs dd W H,aacle ior ssiyhe^qrh-lne msem h*. !\le rhant. s. c. r'dolph^..8 \]uerroz and e @n lru @ie]e for DrcIdriS lerprrd_.oments dd su8S6ti@ on e;d_q_I,6o or t€ mruaipr. The study r4 supporeo-tuao.{y by rhe Aushdlan Reeddr Ctuail(ro K. 5htr) dd llE lo@d.bon for Re*a ndr ud D€_wropmqr.(brc cEnt supporl (o W R. Brard,). J.ffl"

"Y"f '.* f'.".s 1 -d & hbbb ftr tundin8

nrs bp tosoutn Arri.a tud for m@rdsins hjs inrq_€si m reph|€s

LTERATURE CITEDAmRths, R. M. L H. poJcH, A. Coluzo a D A.

ur eulRoz. 1487, fttr erctogical @sr ot moDhu.roSr<d speaal.dtion: teeding by a fo.sondj liidrd.oe@togia (Bedin) 23:139 45.

Am',R. A. t973 N,torphomcrric dd tu nctioMl stud_lps o txe sronach of $e lzad lent aitipa,d. I.@t. \tnd6) r69:t57-47.

B r {, M. 5 to8l. (}rmial Derer of Arthromds,Acadmic Pre, Ns yor(

BpANry, W R. 1a98. A held Eaide ro rhe snarcs ddohpr epnes or :ouLhcm Afnc.. Srruj',, CrDe

BFoaDrF). D G,. aD S. BRoAorE,. Iq7, A Rvie ort\e Mi4op"tti, cqdsb .anpto in srhem AlriurKepnxd: ADphisbamidde). AIL J. Heruelor a6:.

- , C. Ga' aND t, V6sdR |tb, studies m anFptusbadiaG (A mph4baenia. Reprilidr. b. The Rnya- N|lnopc i and Datophia i^ qrtren er"nc..bu . AneL Mus. Nat, Hist 157.311-486

bus,Ac( 5. D I o78. DuJnat \u rface a<+ivftv in rhe ur4lbBaiar 8r,,,5 n@.b (\,bdellii rF7 aR@

D i acertitia, Ahphisbamidaer. J. nerpeloi r):

-. 1088. Bio.Imiat and morphotoqjirt .lifie/_qtiarion in spanish ed Mo--n p"i,t"r.* .rdr,% and uF de*iption of d ne ,pecie. frcn.norrhm \,rodrc {Reptili4 Amptusb;da. Ar_pn6bamj.rae)_ Copeia 198art0l_109.

CaBRq,c, V. R.. AlD H. O MRL!\1. 1990. Tle diel orahphtsbM datuinii lxh.hdta tn Arsdhn2HqPetol R4 21:53-5!.

QuzNErc- A. p, aND A, s. ADE to9t. Diet (mDGrnon or r@ synropic spede of @rroeicJ ;m_pht<bAqia C(rctophi, bb?di Nl A;ahisbtuwtftn. t. HE\rJet.t. 221231240.

Da Wa S, W. P, 1978. The Squera (Reptitjct olre qdEe rre st rq Souih Afrio. tvLr. N6Mus, (btodfontein) 11:1_t6n

IncH.ll. S. 1970. Rdoducfiw .yctes in liz4d< dsnes

Zuruv K3ec M6. Nat. Hist., Misc. pubt.

Gac, C, t968, R€lari@ su@$ of direretur Darhwavl

&Hph6b.mid sp{ialiarim anle riatur uiz:

-. l9l. Studies d Ahphjsbaqjm (ADphi5-Da@4-Kephua,4, A di& of dE mphj6b;qid8os!.Zr6rm. BuU. Al@ Mus. Naa Hisr.144:

--. 1978. np duracr€risric and alfiniris of rheAnphi8bMi4 TrN, Z@1. Soc. Lddh 34:347_

--. 1990. ,Fhneru ir ephisb@ian bioaeotu+pr'):. preliminary arutrst. r, C. pete6;A R.llr-rgs.(e+ l. lr$brgtes iJr rhe nopn 5, pp. 133-r$. ze'0646* rcBchusjiarjlu( dd Museux,Alqands K@nig, Br)m

-_, af,rD C. RHoDEs. 1967. Crmudt lid Tanse_)4ka _(Ahphi5bahja, Reptiti.). Am Car;gieM6.39:112

-, aND D M. KRAKL^U, t98a. Studie 6 Am_phisbeitu (Rephlia) 8. Th ,leM. o( sm.tl huFaes kflom E6r Alri<a {caahius and tMidz;d).Ame Mus. Ndftar€ 2944:l_2a

Cn, M.J., L CLTRxso AMV pmfz.Mr LLAm. l9r.morphomehic ed ecolosv m

dr,,,s.t@.6 (RE riti,: Anphisbdidder I:i+Fpetol. 27205-209.

GpLr& A. C.lcat. I inb redu<rion insquamdB: ido_twagpc &d d,as,on or the

rqds. J. Herpetol. 5:I6Gu3_HLNU, \ 1989 Erologitdj *6r8arion r^ d subter.a_

ned pphtc embtcae in .rid Aushalid. AxFp ntb I d - Re p titia | 0:2n -29 5.

IAR' D, C, M. M. ANToMAZ-1 AND S. M. ATMEDh-sAN--pc, rq97, Litu hisiory nore. t"pto.t@n i,.,6@d'r,&. H€rperot. R@, 2aj 44 4s

KNos roN. c.l, to3b, Lt.rd diAesrion studiB. He-petologica 1.9-10.

LA@\r -R.

1956. \ores he,peteioFques dfnaim5,R4. Z@1. Bot. Aft 52:22+256

'

Lprz, P, l. MiprrN, a\D A. S^Lv{DoR. l99t. Dier*l<bon b rhe amphi.bdqie Btaau. tt@?b.nerpetologica 47:210 218.

-, ^:D - 1994. Rp"potues by amphi,band rd{,"d@pre ro demiels rrod prev or Durdriatry hahrfut mt "peci*. J. ct"ai. e'.ot_ :0,1113�rll9

-, A. SaLvaDo& nM t MaRm. 198. Soil rer.ry.tlt T+. d"$* {g rhe drtrmar ecoros),i'#,:l'.H?il"^

"0"" Blahus dme^. cn .L.vlxDcE, A. lo4t. A Msion of AJn@ tizird< or

Ii,.*rflrJ, Hlf",o"-o"e BurL Mu,. comy.

MAim, J.. P t p AM A. sa,vamp. 1990. Fietd99dy tehperatuE of rhe dphjsbr'qid tizar<ldl,tr,s d@re. Ahpi ibia_Reptilia 11:82_96.

sHIt\E R. 1985, t1le @aturio of ;vipMry in r@tite,_d qologifai ddjysis. r, c. ca; d;d E bilbh(eds,), B@log/ of the Repri lia , Vo1. 15, pa 60*94L. Jols wiley and Soc, N* ydk. _

-, AM_A E GtuR 1991. Why ae duldr si7psnore wDble m &he sp*j6 rhb h oLhftt Erc_lutid 115:1696.1706.

VBEF, I 1967, IiFr rcport of @ovivjpdty in a S@them AJri@ amphisbaeid, MtupAtis ca,ffibz@1. Atricma 3:111-ltt

vm1L. J.. iND !v E. J. Cooqpp. 1985. rhe @otuhorot 'lNd dimo.plGh in the ski'J(EaM6 trtils:M {r}4pl€ of *aat *tectid Cd t zst ;3j995-7002.

WEBB, J..K, AM R Srrl,\r. 1993. p€yffe setectjorl,6ape trdtarbn a d pre<tarq htrsabitity in Auerarq rcrsnares, Anim. Behav 45.111i_rr26