A molecular genetic and morphological appraisal of a distinctive form of the Sandy Inland Mouse, Pseudomys hermannsburgensis

2005·3.5 MB·English

by  M Adams

A MOLECULAR GENETIC AND MORPHOLOGICAL
APPRAISAL OF A DISTINCTIVE FORM
OF THE SANDY INLAND MOUSE,
PSEUDOMYS HERMANNSBURGENSIS
By M. ADAMS
Evolutionary Biology Unit, South Australian Museum,
North Terrace, Adelaide SA 5000
and N.K. COOPER
Western Australian Museum, 49 Kew St, Welshpool WA 6986
SUMMARY the genetic data reveal no
evidence that the two forms are
The molecular genetic tech¬
genetically distinct from one
niques of allozyme electro¬
another and thus demonstrate
phoresis and mitochondrial DNA
they are highly likely to be
sequencing were used to assess
conspecific.
the genetic and taxonomic
affinities of a "gracile” form of
the Sandy Inland Mouse
INTRODUCTION
Pseudomys hermannsburgensis from
the Pilbara region of Western Recent survey work in the
Australia. Measurement of four Pilbara region of Western
external variables plus 26 cranial Australia has revealed several
and dentary variables were also adult specimens of the Sandy
made to assess the nature of any Inland Mouse, Pseudomys
morphological differences hermannsburgensis, whose appear¬
between the distinctive animals ance is distinctive from other
and typical P. hermannsburgensis. specimens in the region. These
Individuals of each morphotype distinctive animals appear
plus other reference specimens smaller and more gracile,
and species were genotyped at 53 comparative in size to a large P.
allozyme loci and sequenced for delicatulus, when compared to
a 307 base-pair portion of the animals displaying the typical
mitochondrial cytb gene. While appearance of an adult P.
the most obvious differences hermannsburgensis. Importantly,
between the two morphotypes these gracile animals are
involve external characters, sympatric with typical P.
there'is some suggestion that the hermannsburgensis, thus ruling
relative shape of the skull may out the possibility that any
also be partly diagnostic. Despite morphological differences have
these morphological differences, resulted from the genetic
216
isolation of a regional subpopu¬ specimens had tissues taken for
lation of P. hermannsburgensis. molecular genetic analysis. How¬
ever, during a survey in
Two hypotheses could account
November 1998 at Brockman
for these unusual animals,
Mine in the Pilbara (22°18”S, 117
namely (1) they represent a
°17'E), several animals repre¬
previously-undocumented
senting both the standard and
morphological variant within
gracile morphotypes were
the species, or (2) they represent
vouchered at the Western
another, presumably new, species
Australian Museum for both the
of Pseudomys. Given that several
preserved specimen and their
species described in the past 20
frozen tissues. The chance to
years were formerly included in
obtain molecular and morpho¬
P. “hermannsburgensis" (Breed
logical data from sympatric
1995), any variant form of the
representatives of both forms
Sandy Inland Mouse is clearly a
provides the ideal opportunity
prime candidate for consider¬
to determine whether the gracile
ation as a new species.
form is indeed a new species, as
Distinguishing between these
suggested by its morphological
alternative explanations is best
distinctiveness, or simply an
achieved using molecular genetic
unusual variant of the Sandy
data to provide an independent
Inland Mouse. The purpose of
assessment of the genetic
this paper is to determine the
affinities of the two forms. Of
taxonomic affinities of the two
the many techniques available,
morphological forms using
allozyme electrophoresis and
molecular genetic and morpho¬
mtDNA sequencing are the most
logical techniques.
suitable and cost-effective
molecular techniques (Avise
1994). The former can determine METHODS
whether the two forms are
Specimens were trapped in the
members of the same biological
field using Elliott Traps or Pit
species, whilst the latter can
Trap/fences. Animals were
resolve the evolutionary
euthanased, numbered, and
affinities of the variant form
livers were immediately removed
amongst other related species of
into liquid nitrogen. The animal
Pseudomys (to ensure that any
was then preserved in 4%
“new" taxon does not turn out to
formalin before being washed
be a variant of an already-
and stored in 70% ethanol. Skulls
described species).
were removed and cleaned for
Previous field workers have also
morphological comparison.
recognised two morphotypes of
P. hermannsburgensis in the field,
Morphological measurements
(pers. comm. Norm Mckenzie, Ken
Aplin, and Roy Teale), although Given that, by definition,
unfortunately no aberrant “unusual" morphotypic forms are
217
only rarely encountered in the burgensis were included in the
field and even less commonly morphological analyses to
taken as vouchers, the small provide a more complete picture
sample size (n=5) available for the of morphological diversity in the
gracile form (hereinafter referred “parent" taxon. The details of all
to as Pseudomys sp. for animals subjected to morpho¬
convenience) precludes any com¬ logical analysis are presented in
prehensive statistical analyses of Table 1.
the morphological data. This External and cranial measure¬
limitation of small sample size is ments of all specimens were
further compounded by the fact made using digital callipers. Four
that gender and adult age class external characters were
differences can never be properly measured, namely.- HV, head vent
explored in any rare taxon (ie. length; TV, tail-vent length;
Pseudomys sp.). As such, the best PESL, pes length; and EARL, ear
that can be achieved herein is a length (Table 2a). The following
qualitative assessment of the cranial measures were recorded
morphological differences (Table 2b), as outlined in Cooper
between the two forms, in et al. (2003): GL, greatest length;
combination with a basic BD, braincase depth; 1PW,
Analysis of Variance for each
interparietal width; BW, brain-
individual character. In regard to case width; Z\V, zygomatic width;
the latter, it must be remembered 1\V, interorbital width; NL, nasal
that, due to the small sample sizes length; N\V, nasal width; BUW,
involved, the chance of a "type bulla width; BL, braincase length;
11” statistical error (i.e. falsely PL, palate length; M'L, upper
accepting the null hypothesis molar 1 length; M3L, upper molar
that the two forms do not differ 3 length; M'M3, upper molar 1 to
significantly for a given molar 3 length; APF, anterior
character) remains unavoidably palatal foramen; C1L, condyle to
high in any univariate statistical incisor length; and M,M3, lower
test.
molar 1 to molar 3 length. In
Only adult animals were addition, a series of extra cranial
included in this study. Animals measurements, not used by
were considered adult if they Cooper et al. (2003), were taken:
were reproductively mature and BUL, bulla length; WOB, width
if skull sutures were fused. Two outside bullae; W1B, width
age classes were observed, based between bullae; M2L, upper molar
on dental differences; class 3 = 2 length; MTD, mesopterygoid
mature adult with worn teeth distance; PTD, pterygoid distance;
and class 2 = adult with slight PTW, width of pterygoid at tip.
wear.on teeth. Although all five To qualitatively assess the extent
Pseudomys sp. available were to which the two forms were
males, both male (n=4-5) and diagnosable using the morpho¬
female (n=3) Pseudomys hermanns- logical data, a separate Principal
218
Components Analysis (PCA) was of any differences in allozyme
performed on each of the frequency between the two
external and cranial datasets. The morphotypes was assessed using
statistical significance of any the computer program
differences between the two GENEPOP (Raymond and
forms was assessed for each Rousset 1995).
variable by Analysis of Variance
(ANOVA). Both procedures were
mtDNA sequencing
carried out using the computer
Two individuals of the variant
program STAT1ST1CA.
morphotype plus one typical P.
hermannsburgensis were
Allozyme analysis
sequenced for a 307 base-pair
Frozen livers were available in portion of the cytochrome-b
the tissue collections of the (cytb) mitochondrial gene,
Western Australian and South according to standard protocols
Australian Museums. Four (Hillis et al. 1996). These sequences
specimens of Pseudomys sp. from were compared to an existing
two locations were available for cytb database previously
molecular analysis. These were generated in our laboratory and
compared to 13 typical Pseudomys comprising P. hermannsburgensis
hermannsburgensis taken from six plus its near relatives. The data
locations, including two sites were analysed both by eye and by
where both forms co-exist. Single constructing a neighbour¬
specimens of P. bolami and P. joining tree from the Jukes-
chapmani, two species previously Cantor genetic distance matrix,
considered conspecific with P. using the computer program
hermannsburgensis, were also MEGA (Kumar et al. 1993). Table 1
included. The details of all provides details of which animals
specimens screened are were included in the mtDNA
contained in Table 1. study.
Allozyme electrophoresis was
undertaken on cellulose acetate
RESULTS
gels according to the principles
and procedures detailed in
Richardson ct al. (1986). A total of External morphology
53 loci displayed sufficient From initial comparison of the
activity and resolution after bodies of the two morphs, the
electrophoresis to allow Pseudomys sp. individuals, though
allozymic interpretation. Details fully reproductively mature
of the locus abbreviations are with descended testes and
presented in Georges and Adams epididymis, were obviously
(1992) whilst the nomenclature smaller than fully mature males
used to refer to loci and of P. hermannsburgensis, even in
allozymes follows Adams et al. sympatry (Brockman Mine).
(1987). The statistical significance There, a mature male P.
219
m, de
uo
eC
Musn.
o
an ecti -ua k ro N (S o- cnbb^bb'b'Ncobbbb^bbb
Australies Collce. *3co-> o-O— n' Oboi"o - oVOo - Oo^OV -- oOO25 Ojr! oKO bo oVO oO bO bO OoO inO n-O V-O N-° J^O .m2 -m,0 o
un
n ssue
erTiq
Westgical NA se » Io < 0CO0 r^) vO X) in L>n, r•n—< O<n' vO OO LN-*, LN-“. bN" vNO- oo oo oo oo K<n- OO oo oo
WAMM = alian Biolos, D = mtD cd oCcCTNoN" rNCCNN- ooOCNN " oooCNN * oroCnN OCCCNNNN “ ohCCNN"- ooCCNNo-1 ooOCNN ~ ormCoN - OC«CNNNn - OC<CNNNn " oO<CNNn " ovOmCON oCoriN - ooCr0nN4 OoCr0ON4 Si0n41 oGonCNO - O0o044* oo0044- obON-1
umbers:= Austrurement < < < < &< <<< < < < < < < < < ClO/ T^^ ^CzO 7Hu
for Accession NMuseum-, ABTC = external meas c2o 2co ^cOdJ xCcd:d Pu2Gcccd-Jl 2CcO 2CcO 2cco JucucOdd Xurucdt C7U<cO*GD 7CU<COUG 7CU(OOGJ1 7PUc<QG!D ZxSOc:J Z c£cd- Cciad s.cC5d ~‘unO-GCS.BJ,J. i 12-*vScc10-,d»-3 oiycrc5§v—ddtj H HCCc5Sg-dJ
udy. Code Australian rements, E pC>Oj cPq. OCii uGuOJ- CwO P^< C/L?) < < v< %< w<> p<:j < <> ^t<*o ^t<^o> :<pqqq
his stM = measu
ns used in tuseum, AMSs, S = skull •(Vta?6ofxl.(cid:9632) s> "(a£o3/) oIC2o£r-tL0 rwCo2£.L0 <o2£/0) 3c33c3G3ooO 333c3D3c<oou4 -33<D3c331oO* 33<b3c33oyo -3Db33O -3%b33»o -vv33CC33ooO -v3C3c333voooO. -33'c3C33UOo -3Ob3c333oJo •V33cv3<DOoou3O 3C3b3tC3r3ouOOo •cC3>D3c33ooOi3Oj 333c33Cc-DuooOO 33c3bDc33ooJO 33cDc33DsooJO 3v33sD3boJO
specimealian Mallozyme Oc3<hXoi C3cLo, “L3C3O “L3c3o “L3C<3OiJ -CE3VO3JL- -C3V32OJL- C3EL C3EL tLCLC-3£>«3Lu- C-3£v<eLu- C-33£><LU- t-L33£*<U-C -LO33£VJ-C »L>3£O>C-JC 3L3v£<X-JC 3L3£ui~C L3£C L3£C L3£
Table 1. Details of all SAMM = South Austrfor Data column: A = 2<sJ e«3 Oi(2^ms<ON) 2sfuNNn<O-v 2s<CrT-O3Ot 222Sr<f Sf22><:n CrS<jN- S^^<—2< froT<-iif 22O2r<ozN- 22°TcmfS 22^02<0: 22Cr1<^O3\ 22^c<-of 22< 22< >rua22<°on*i >22Bor<t*on- rC22CIo<TOO--) 22COOT<Of 2CNttC2<>qON O22r*(cCNOn- 5uafOi<—noN
220
hermannsburgensis collected from
site NA52 on 22 November 1998,
weighed llg, whereas a mature
male Pseudomys sp. collected at
°55'00’ °32'00‘ °26'37" 9oO0-4. oIron- 1 °Oion orr00rOO44 - twPhseeeiu gsdhaomemdey ss8 si.tp6e.g wo (na2 s0t hp%he ylpsirgiechvatlieloryu) .ss m Tdahalyel
139138139 ° 2 2 rO and gracile, more like P.

delicatulus than P. hermanns¬
burgensis. The pelage of the
5'00'0'00'6’35 OOO' lLO lrnO-(cid:9632) O- oPfs ePu.d hoemrmysa nspn.s bwuarsg esnismisi.l aAr ltthoo tuhgaht
°3°2°3 O04 OT t- OrO both were sympatric in the sense
333130 04 04 CN (O-nNJ of being collected at the same

site, it was not possible to
< < determine if they were truly
A
ms, SArge, SAation, S 5<- &cOrt &4coc_d» “mAs yiPcnCrtooA-p hiocan"b iit.teah.t eo. cecxutpeyrninagl vthaeri asbamlees
DaGoSt C *-» AJ is presented in Fig la). As the
drew china noona 6£<u opnrees eonfc et hoef Pa. hmeirsmsainngn sbvuarlgueen siins
An BraBalca 2spa)e cwimase cnasu s(WingA MthMis4 s1p8e3c3i;m Tenab tloe
appear as a significant outlier
(from both Pseudomys sp. and the
other P. hermannsburgensis speci¬
ADD <PP
mens), this specimen was omitted
from the final analysis. The PCA
qualitatively demonstrates the
distinctiveness of the four speci¬
mens of Pseudomys sp. when
C C £
mimimi <3 d C2 compared to typical P. hermanns¬
P.bola P.bola P. bola ~a•<oc:3a ,~a•«uc:» ,-a-auca:* CIbnuotregmerenpssoitsin,n egbnloytt ,h thmea ilfsei rastn dP hrfieenamcviapillaeyl.
influenced by the variables HL
and PESL, despite the most
striking dichotomy in the raw
data being found in the variable
i^no n^ tO-' EARL (Table 2a). This obser¬
M17273C67582C13341 vrSjO- S0rO4 20To4f vonat iont hise supfpoourtre d biny dAivNiOduVaAl
MTT 2 22 characters, in which only EARL
SAABAB ^< S<* ^< showed a statistically-significant
221
difference between the two skulls, the cranium in Pseudomys
morphotypes (p=>0.01 for all sp. appears to be more rounded,
adult males). the upper molars narrower, the
molar row shorter, the bullae less
Cranial morphology inflated though wider, the
From an initial observation of anterior palatal foramen reaches
Table 2a. External measures for the four Pseudomys sp. and seven P.
hermannsburgensis examined. Code for sex: 1 = male, 2 = female. Code for age class:
2 = adult, slight wear on teeth, 3 = mature adult, worn teeth. A dash (-) indicates a
missing value.
Animal Form cnvX Age AH >H PESL EARL

M44138 sp 1 2 58.4 73.5 14.9 9.1
M41305 sp 1 2 56.4 69.9 16.2 8.2
M52437 sp 1 2 56.7 71.8 16.5 9.0
M52452 sp 1 2 55.9 74.1 15.7 7.6
M43170 Ph 1 2 48.0 79.0 16.7 11.7
M52411 Ph 1 2 64.0 90.0 17.4 10.2
M41833 Ph 1 3 65.0 - 14.8 10.2
M48514 Ph 1 3 63.5 79.0 16.0 10.6
M48513 Ph 2 3 63.0 80.0 16.5 12.3
M41813 Ph 2 3 61.6 72.5 16.5 12.5
M52425 Ph 2 3 62.0 77.7 16.7 10.9
Table 2b. Skull measures for the four Pseudomys sp. and eight P. hermannsburgensis
examined. Codes as for Table 2a.
Animal Form cnXCJ Age O Om IPW BW zw £ -ZJ- NW BUL BUW WOB
M41305 sp 1 2 20.67 7.37 8.03 10.32 10.64 3.22 7.01 2.46 5.21 4.85 10.08
M52437 sp 1 2 21.68 7.04 6.99 10.01 10.60 3.14 7.20 2.37 5.04 4.70 9.92
M52452 sp 1 2 19.79 6.53 6.93 - 10.12 3.41 6.89 2.54 4.86 3.70 9.77
M52371 sp 1 2 21.71 7.62 6.50 10.54 11.14 3.51 6.99 2.56 5.21 4.70 10.46
M41304 Ph 1 3 22.62 6.91 7.60 10.50 11.17 3.51 8.48 2.64 5.64 5.07 10.71
M52411 Ph 1 2 21.86 7.30 7.05 10.25 10.81 3.58 7.26 2.52 5.38 4.78 10.07
M41801 Ph 1 2 19.83 7.05 7.63 10.31 11.07 3.36 6.72 2.62 4.95 4.56 9.85
M41833 Ph 1 3 22.06 6.67 7.56 10.07 10.91 3.55 7.32 2.60 5.12 4.70 10.21
M48514 Ph 1 3 21.57 7.38 8.31 10.46 11.51 3.36 7.95 2.41 5.58 5.28 10.75
M48513 Ph 2 3 - 7.21 8.25 10.52 11.21 3.52 7.71 2.63 5.33 4.98 10.26
M41813 Ph 2 3 22.84 6.59 7.64 10.28 10.79 3.50 8.07 2.65 5.49 4.67 10.81
M52425 Ph 2 3 22.41 6.98 7.39 10.06 10.65 3.41 7.91 2.47 5.26 4.96 10.29
222
the anterior end of upper molar 1 Pseudomys sp. before a definitive
(as opposed to not reaching the answer on comparative skull
start of the molar row) and the morphology can be given.
pterygoids appear to be more
flared and wider at the tips than
Allozyme analysis
that of an average P.
Thirty-five of the 52 loci used in
hermannsburgensis.
this study were variable,
A PCA on the skull variables (Fig
displaying between two and four
lb) indicates that while two of
alleles. The remaining seventeen
the four Pseudomys sp. have
loci (Ap-3, Ca-l, Est, G6pd} Gdh,
moderately distinctive scores at
Gldh, Glo, Got-1, Gpx, Hb, ldh-2,
Principal Component 1, the other
Lap, Mdh-2, Ndpk, Pgam, Pgk, and
two specimens lie squarely
Pk-2) were monomorphic. Table 3
within the P. hermannsburgensis
presents the allozyme profiles for
cluster. Thus there is no strong
all 19 Pseudomys at the 35 variable
indication that the two
loci.
morphotypes show any quali¬
tative differences in skull The two morphotypic forms of
characteristics above and beyond the Sandy Inland Mouse share
the variance displayed within alleles at all loci. This contrasts
each morphotype. This con¬ markedly when either is com¬
clusion is backed up by ANOVA pared with the other two species
on individual characters, which examined. Thus R bolami, a species
did not reveal any statistically- closely-related to P. hermanns¬
significant differences between burgensis and until recently
the two forms. Clearly a much considered to be conspecific
larger sample size is required for (Kitchener et al. 1984), displayed
U
WIB CQ PU MIL M2L M3L M1W M1M3 M1M1 MTD OHPU PTW APF C1L 22
1.35 17.44 11.10 1.72 1.05 0.78 1.07 3.53 4.50 1.01 0.99 0.54 3.90 12.46 3.19
1.14 16.68 10.20 1.55 0.50 0.97 1.06 3.16 4.42 0.97 0.80 0.45 3.29 12.95 2.93
1.21 17.03 10.18 1.84 0.99 0.79 1.18 3.37 4.42 0.95 - 0.75 3.74 11.80 2.80
1.75 17.95 11.22 1.76 0.98 0.53 1.07 3.48 4.53 0.95 1.30 0.58 3.74 11.98 3.20
1.27 18.74 11.63 1.84 1.03 0.77 1.11 3.44 4.70 1.22 0.96 0.47 3.42 13.45 3.15
1.12 18.07 11.12 1.77 1.14 0.73 1.16 3.43 4.56 0.74 1.06 0.51 3.73 12.97 3.33
1.24 16.24 10.15 1.65 1.12 0.70 1.04 3.41 4.27 0.90 0.96 0.55 4.08 10.90 3.15
1.33 18.18 11.08 1.91 1.01 0.67 1.13 3.42 4.70 1.06 1.32 0.43 3.19 13.05 3.14
1.44 17.76 11.02 1.72 0.98 0.71 1.11 3.41 4.82 1.01 1.25 0.36 3.77 12.93 3.06
1.24 17.35 11.12 1.82 1.15 0.59 1.15 4.77 4.78 0.92 1.04 0.60 3.82 12.81 3.31
1.26 10.59 11.65 1.78 1.07 0.82 1.12 3.49 4.58 1.08 1.12 0.48 3.93 13.83 3.33
1.30 18.32 10.95 1.83 0.97 0.76 1.13 3.44 4.66 1.14 1.07 0.38 4.05 13.38 3.37
223
"
a) P. hermannsburgensis
*0.
2
5*
O'
'S’ V
S-
n
.
o P. sp.....
3
\ \
O
a \ (cid:9633) \
o / •
D (cid:9633) (cid:9632))
(cid:9632)
Principal Component 1
b) -..
I • ..
S3 |
O
(cid:9632)5" \ (cid:9632) /
/
— \
n / (cid:9632)
o
3 (cid:9633)
T3
n (cid:9632)
O
S3
a
SP‘ \ P. hermannsburgensis
\ •
Principal Component 1
Figure 1. Principal Component Analysis of a) external and b) skull measures. Each
animal has been plotted for their individual scores at the first two principal
components extracted. Legend for specimens: closed circles = P. sp., closed squares
= male P. hermannsburgensis; open squares = female P. hermannsburgensis. Specimen
WAMM41833 was excluded from analysis a) due to the distortion caused by a
missing value (see text for details).
fixed differences at 18% of loci 1980) differs from both P.
(data in Table 3), and R chapmani hermannsburgensis and P. bolami at
(once also included in P. 40-42% of loci examined. All
hermannsburgensis; see Kitchener species of Pseudomys examined to
224
Table 3. Allozyme profiles at 35 variable loci for the 19 Pseudomys examined.
Identified by museum number and abbreviated taxon.
ol ust
Psp Pherm Pb Pa

Locus U"i(f'NtT)* 52437 44138 41305 52425 52411 52410 44139 41304 41801 41813 41833 41837 43170 48513 48514 18754 17273 47645
A cp a a a a a a a a a a a a a a a a a a ab
Acyc b b b b be be b b b b b b b be b b b be a
Ada a a b ab a a a ab a ab a a a a ab ab a a b
Adh-l a a a a a a a a a a a a a a a a a b c
Adh-2 ab ab b b b b b b b b b b b b b b ab b b
Ak-1 a a a a a a a a a a a a a a a a a a a
Alc-2 b b b b b b b b b b b b b b b b b ab c
Alb c c c c c c c c c c c c c c c c c b a
A p-l b b b b b b b ab b b b b b b b b b b b
Ap-2 b b b b b b b b b b b b b b b b b a c
Ca-2 b b ab b b b b b b b b b ab b b b b b c
Dia b b b b b ab b b b b b b b ab ab b b b a
Enol c c c c c c c c c c c c c c c c c b a
Fdp b b b b b b b b b b b b b b b b b a c
Fum a a a a a a a a a a a a a a a a a a b
Gda b b b b b b b b b b b b b ab b b b ab b
Got-2 bd bd b b b b d b b b b bd b b bd bd bd c a
Gpi a a a a a a a a a a a a a a a a a b b
Gpt a a a a a a a a a a a a a a a a a a b
Hbdh a a a a a a a a a a a a a a a a a a b
ldh-l a a a a a a a be a cd c ac a a a a a a a
Ldh b b ab b b b b b b b b b b b b b b b b
Mdh-1 a a a a a a a a a a a a a a a a a a ab
Me a a a a a a a a ab a a a a a a a a a c
Mpi b b b b b b b b b b b b b b b b b c a
Np b b b b b b b b b b b b b b b b b ab b
Pep A b b b b b b b b b b b b b b b b b b a
PepD a a a a a a a a a a a a a a a a a a ab
6Pgd b b b b b b b b b b b be b b b b b a d
Pgm-l a ab a a a a a a a a a a a a a a a a a
Pgm-2 c c c c c c c c c c c ac ad c c c c c be
PkA a a a a a a a a a a a a a a a a a a b
Sod b b b b b b b b b b b b b b b b b b a
Sordh b b b b b b b b b b b b b b b b b b a
Tpi a a a a a a a a a a a a a a a a a a b
date have been diagnosable from frequencies for each morphotype
one another using allozyme data at the 14 loci polymorphic
(Baverstock etal. 1981). within the Sandy Inland Mouse.
Table 4 summarizes the allozyme The two morphotypes have
225