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动物学报 50(4):490 - 503 , 2004
Acta Zoologica S inica
Received Apr. 27 ,2004 ; accepted May 19 ,2004
33 Corresponding author. E2mail :k bade @sandiegozoo. org
ν2004 动物学报 Act a Zoologica Si nica
A positive relationship between baculum length and prolonged in2
tromission patterns in mammals3
Alan DIXSON33 , J enna N YHOL T , Matt AND ERSON
Center for Reproduction of Endangered Species , Zoological Society of San Diego , P. O. Box 120551 , San Diego , California 921122
0551 , USA
Abstract Elongation of the baculum may have evolved , in part , in association with copulatory patterns which involve a
prolonged intromission. However , this hypothesis has been disputed , for North American carnivores. To test t he hypoth2
esis , we assembled data on baculum length and body weight for a sample of 315 species , representing 144 genera of carni2
vores , bats and p rimates. A linear multiple regression (ANCOVA)was undertaken for 39 genera for which intromission
durations are known , in addition to baculum length and body size. This revealed a highly significant , positive association
between baculum length and intromission duration (r2= 0165 , F = 40148 , P < 010001). Subsequently , data were ana2
lyzed at species level (n= 57)after controlling for phylogenetic bias in the dataset (using Comparative Analysis of Inde2
pendent Contrasts: CAIC). This analysis confirmed a strong correlation between baculum length and intromission duration
(r2= 0169 , F = 34123 , P < 01001). Results of t his study support t he prolonged intromission hypothesis for the evolu2
tion of baculum length [ Acta Zoologica Sinica 50 (4): 490 - 503 , 2004 ].
Key words Baculum , Sexual selection , Intromission duration , Carnivores , Bats , Primates
哺乳动物阴茎骨长度与延长性插入模式之间存在正相关的关系3
Alan DIXSON33 , J enna N YHOL T , Matt AND ERSON
Center for Reproduction of Endangered Species , Zoological Society of San Diego , P. O. Box 120551 , San Diego , California 921122
0551 , USA
摘 要 阴茎骨长度增加的进化 ,部分原因与交配模式有关 ,后者涉及到延长性插入持续时间。但是 ,对于北
美的食肉动物来说 ,这个假说一直有争议。为了检验这个假说 ,我们收集了来自食肉动物、蝙蝠和灵长类的 144
个属 315 种哺乳动物阴茎骨长度和体重的数据 ,除了阴茎骨长度和体重以外 ,对已知的 39 个属的插入持续时间
进行了线形多次回归分析。结果表明:阴茎骨长度与插入持续时间之间存在极显著的正相关关系 (r2= 0165 , F
= 40148 , P < 010001)。然后 ,使用了独立对比的比较分析以控制数据系统发育的偏差 ,在物种水平上对数据进
行了分析 ,结果证实:阴茎骨长度与插入持续时间之间有显著的相关关系 (r2= 0169 , F = 34123 , P < 01001)。
本研究支持阴茎骨长度进化的延长性插入假说 [动物学报 50 (4): 490 - 503 , 2004 ]。
关键词 阴茎骨 性选择 插入持续时间 食肉动物 蝙蝠 灵长类
An os penis , or baculum , occurs in five mam2
malian Orders (Primates , Rodentia , Insectivora ,
Carnivora and Chiroptera)although bacular morphol2
ogy is highly variable and the structure is lacking in
certain species (Burt , 1960 ; Romer , 1962 ; Dixson ,
1998). One hypothesis to explain the evolution of e2
longated bacula in mammals is t hat long bacula occur
in species which prolong intromission , during copula2
tion (Primates: Dixson , 1987 ; Carnivores : Dixson ,
1995). However , a recent study of North American
carnivores , by Larivière and Ferguson (2002), failed
to confirm this hypothesis. Larivière and Ferguson al2
so refuted two alternative hypotheses :that the bacu2
lum may assist males in attaining intromission (Long
& Frank , 1968)or that it may stimulate the female
and induce the luteinizing hormone surge required for
ovulation (Greenwald , 1956). Larivière and Fergu2
sonπs analysis was confined to North American carni2
vores (52 species representing 36 genera), for which
intromission durations were available in 18 cases , 16
of which involved species with extended intromission
copulatory patterns (> 3 minutes in duration).
Before the hypothesis that baculum length and
intromission duration are positively correlated can be
refuted , we believe it advisable to test t he relationship
using a much larger data set. Accordingly , we have
examined relationships between baculum length and
body weight in 315 mammalian species , representing
144 genera of carnivores , bats and primates. Data on
intromission durations were located for 57 species (39
genera)allowing a more robust test of the possible re2
lationship between residual baculum length and pat2
terns of intromission in mammals.
1 Materials and methods
Data on adult male body weight , baculum length
and (where known)intromission patterns were as2
sembled from previous publications (bats: 174
species , 94 genera : Hosken et al. , 2001 ; Primates :
70 species , 40 genera : Dixson , 1998 ; Carnivores : 83
species , 46 genera : Dixson , 1995 ; Larivière and Fer2
guson , 2002). These data are included in Appendix
Ⅰ. Information on absolute intromission durations
was compiled for 57 species , 39 genera (Table 1). A
double logarithmic plot of baculum length versus body
weight was used to calculate residuals of baculum
length.
A linear multiple regression was undertaken at
genus level (ANCOVA , n= 39 )using baculum
length (dependent variable), intromission duration
(independent predictor)and body weight (indepen2
dent co2variant ); all variables were forced through
the origin. Subsequently , a second multiple regres2
sion was undertaken at species level (n= 57)after
controlling for phylogenetic bias in the data set. Be2
cause related species share associations among many
traits , due to their shared evolutionary descent , it is
not possible to treat species as independent points for
statistical purposes (Felsenstein , 1985). Therefore
the multiple regression at species level was conducted
by using Comparative Analysis of Independent Con2
trasts (CAIC)to transform the species data set into
phylogenetically independent contrasts (Purvis and
Rambaut , 1995 ; Pagel , 1992).
CAIC requires the use of a phylogenetic tree for
the species under investigation. We employed a com2
posite phylogeny incorporating t he trees constructed
by Purvis (1995), Johnson and OπBrien (1996),
Bininda2Edmonds et al. (1999 ), and Liu et al.
(2001).
Previous analyses of residual baculum lengt h ver2
sus intromission duration have compared baculum
lengths in mammals with “long”intromission pat2
terns of copulation , with t hose in which intromission
is relatively brief. An arbitrary measure has been
used , with 3 minutes as cut2off point between
“short ”and “long”intromissions (Dixson , 1987 ,
1995 ,1998 ; Larivière and Ferguson , 2002). One ad2
vantage of this approach is that many more data exist
on intromission durations which are known to be
greater (or less than)3 minutes t han on exact intro2
mission durations. In Appendix Ⅰ, it was possible to
classify 76 species , representing 49 genera , as having
shorter duration intromissions (S , < 3 min)or longer
duration intromissions (L , > 3 min). These data
were analyzed at genus level , and (post CAIC)
species level in order to compare residuals of baculum
length in the two groups. Non2paired ttests (one2
tailed)were used to make this comparison.
2 Results
Fig11 shows a double logarit hmic plot of bacu2
lum length versus body weight for adult males of 315
species of carnivores , bats and primates. Linear mul2
tiple regression at the genus level , using baculum
length (dependent variable), intromission duration
(independent predictor)and body size (independent
co2variant), revealed a highly significant positive as2
sociation between baculum length and intromission
duration (r2= 0165 , F = 40148 , P < 010001). This
was confirmed by (post2CAIC)analysis of data at the
species level (r2= 0169 , F = 34123 , P < 01001).
These data are shown in Fig12.
Residuals of baculum length in mammals which
have intromission durations of > 3 minutes were
(mean ±S E)+ 01422 ±01049 (n= 26 genera), as
compared to - 01338 ±01053 (n= 24 genera)in
forms which intromit for shorter periods. This differ2
ence was statistically significant both at t he genus lev2
el (F= 7110 , P< 01001)and at the post2CAIC
species level of comparison (F= 3112 , P< 0105).
Because no data were available on intromission dura2
tions in bats , we recalculated residuals of baculum
length for our sample to include only the carnivores
and primates (Appendix Ⅰ
). On t his basis , residuals
of baculum length for species with extended intromis2
sions averaged + 01383 ±01044 , as compared to -
01372 ±01051 in carnivores and primates with short2
er intromission durations (i. e . < 310 min). This dif2
ference was again significant at both genus level (F=
7102 , P< 01001)and post CAIC species level (F=
3111 , P< 0105).
Finally , using data o n exact intromission dura2
tion for 39 genera and 57 species (Table 1)we tested
for possible correlations between adult male body
weight and intromission duration. No correlation oc2
curred between these two variables (r2= 2138 , P =
0143).
194
4期Alan DIXSON et al. : Baculum length in mammals
Fig11 Double logar ithmic plot of baculum length against body weight ( y= 01422 x- 01304) for 315 species of carnivores, bats
and primates
Fig12 Results of a multiple regression analysis ( ANCO2
VA) demonstrating a positive correlation between baculum
length and intromission duration f or the 57 species of car2
nivores and primates listed in Table 1 ( P< 01001)
3 Discussion
The present report confirms and strengt hens pre2
vious findings on primates and carnivores (Dixson ,
1987 , 1995 , 1998)indicating a positive relationship
between baculum length and intromission duration
during copulation. We have also addressed the criti2
cism raised by Larivière and Ferguson (2002)that
failure to use comparative statistical methods to con2
Table 1 Intromission durations in those mammalian species
for which data on baculum length and body weights are avail2
able ( see Appendix 1)
Species Intromission
duration 3
(minutes)Source
Order Carnivora
Eumetopias jubat a 16160 Schusterman , 1968
Halichoerus gry pus 30100 Hewer , 1957
Leptonychotes
weddelli 5100 Cline , Siniff & Erickson , 1971
Mi rounga
angustirostris 5150 Le Boeuf , 1972
Ursus arctos 35100 Sparrowe , 1968 ; Craighead et
al. 1969
Procyon lotor 60100 Larivière & Ferguson , 2002
Canis l upus 120100 Gensch , 1968
Canis f am ili aris > 60 Beach , 1968
Canis l at rans 25100 Larivière & Ferguson , 2002
V ul pes v ulpes 22150 Lloyd , 1980
Nyctereutes
procyonoides 10100 Kleiman , 1968
Fennecus zerda 75100 Petter , 1957
Mustela nivalis 90100 East & Lockie , 1965
Mustela erminea 20100 Larivière & Ferguson , 2002
Martes martes > 60 Schmidt , 1934 , 1943
Martes foina > 60 Schmidt , 1934 , 1943
Martes americana 90100 Larivière & Ferguson , 2002
Martes pennanti 370100 Larivière & Ferguson , 2002
M ustela f renata 240100 Larivière & Ferguson , 2002
Mustela nigri pes 180100 Larivière & Ferguson , 2002
Mustela vison 64100 Larivière & Ferguson , 2002
294 动 物 学 报 50 卷
Continued
Species Intromission
duration 3
(minutes)Source
Order Carnivora
Meles meles 35100 Neal , 1986
L ut ra l utra 22150 Laidler , 1982
Lont ra canadensis 24100 Liers , 1951
Enhydra l utris > 14 Kenyon , 1969
Gulo gulo 27100 Larivière & Ferguson , 2002
Felis catus < 0125 Rosenblatt , 1965
Pant hera leo < 1 Schaller , 1972
Pant hera tigris 1170 Sankhala , 1967
Pant hera onca < 1 Stehlik , 1971
Felis concolor 1100 Larivière & Ferguson , 2002
Felis pardalis 2100 Larivière & Ferguson , 2002
Mephitis mephitis 20100 Larivière & Ferguson , 2002
Order Primates
Microcebus murinus > 3100 Martin , 1973
Daubentonia
madagascarensis 62100 Sterling & Richard , 1995
Loris tardigradus 13150 Dixson , 1989
Gala goi des de mi doff 60100 Charles2Dominique , 1977
Otolem ur garnettii 136150 Eaton et al. , 1973
Callit hrix jacchus 01092 Dixson , 1986
Cebuella pygm aea 01117 Soini , 1988
Saguinus oedi pus < 0150 AFD
Aotus lem urinus < 0150 AFD
Nasalis larvat us 01692 Yeager , 1990
Chlorocebus aethiops < 1100 Gartlan , 1969
Miopithecus talapoin < 1100 Dixson et al. , 1975
Lophocebus albigena 0144 Wallis , 1983
Mandrillus sphinx < 1100 AFD
Mandrillus
leucophaeus < 1100 AFD
Papio u rsinus < 1100 AFD
Macaca nigra < 1100 AFD
Macaca mulatt a < 1100 AFD
Macaca f uscata < 1100 AFD
Macaca arctoides > 3100 Goldfoot et al. , 1975
Pongo pygm aeus 14100 Nadler , 1977
Pan troglodytes 01117 Tuti n & Mc Ginnis , 1981
01137 Hasegawa et al. , 1990
Pan paniscus 01255 Kano , 1992
Gorilla gorilla 1160 Harcourt et al. , 1981
3Data are means , o r mid2points of ranges where only ranges were avail2
able. A FD = aut horπs unpublished observations.
trol for phylogenetic biases in the data set may have
produced a spurious result in the study of carnivores
(Dixson , 1995). Failure to employ comparative tech2
niques can produce spurious results due to phylogeny
(Berrigan et al. , 1993); hence we have used CAIC
and appropriate phylogenies as required by the com2
parative method (Pagel , 1999). We have also includ2
ed the most extensive data set thus far analyzed , in2
corporating data on 315 species and 144 genera of
mammals.
Linear multiple regression , at genus and (post
CAIC)species levels demonstrated a highly signifi2
cant association between baculum length and intro2
mission duration for the 39 genera and 57 species for
which more detailed information on intromission du2
rations is available (Table 1). However , we have also
included an analysis of intromission durations in mam2
mals where intromission is prolonged (> 3 mins)as
compared to those in which it is of shorter duration
(< 3 mins). It is acknowledged t hat the“cut2off”
point , at 310 minutes , between the two groups is ar2
bitrary. However , this approach , as used in previous
studies (Dixson , 1987 , 1995 , 1998 ; Larivière and
Ferguson , 2002)does have the advantage that many
more genera (n= 49)and species (n= 76)could be
included because data were available on whether in2
tromission lasts for more , or less , than 310 minutes.
At both genus and (post CAIC)species levels , this
analysis confirms that residual baculum length is sig2
nificantly greater in mammals with longer periods of
intromission. Body weight alone does not correlate
wit h intromission duration ; it is not t he case t hat
larger mammals intromit for longer periods t han
smaller species.
In their studies of North American carnivores ,
Larivière and Ferguson (2002)comment that their a2
bility to detect possible relationships between baculum
length and intromission duration “may have been
weakened by o ur data set. ”Appropriate comparative
statistical procedures were used by these aut hors , but
unfortunately data on intromission durations were
available for only 18 carnivores. A weak positive cor2
relation (P< 0108)was obtained between baculum
length and intromission duration but removal of the
only two species of felids with short intromission
times (Puma concolor and Herpailurus
yagou raroundi)caused this trend to disappear. The
remaining 16 species all exhibited long intromissions
ranging f rom 23 minutes (Ursus arctos)up to 370
minutes (M artes f oi na). By contrast in the current
study we have been able to draw upon a more exten2
sive data set including both carnivores and primates.
Statistical procedures , including comparative CAIC
analysis , confirmed t he significant relationship be2
tween baculum length and intromission duration for
394
4期Alan DIXSON et al. : Baculum length in mammals
this sample. However , we do not suggest that fur2
ther analyses are unnecessary. On the contrary , the
“prolonged intromission hypothesis”requires further
testing using broader data , especially from rodents
and those insectivores where a baculum is present.
Despite inclusion of the bats in our study , to improve
the quality of our regression analyses and calculations
of residuals of mammalian baculum length , it has thus
far not been possible to examine the question of intro2
mission durations in t his mammalian order ; because
data on copulatory behavior are so sparse (Hosken et
al. , 2001).
It is unlikely that baculum length can be corre2
lated with the occurrence of induced ovulation in
mammals , and we agree wit h Larivière and Ferguson
(2002 , 2003)and Ferguson and Larivière (2004)on
this question. Thus , elongated bacula occur in pri2
mates , such as bushbabies , lorises and stumptailed
macaques , which are spontaneous ovulators (Dixson ,
1987 , 1998). Whether t he baculum might assist
males to attain intromission (Long and Frank , 1968)
is also doubtful given the lack of relationship between
increased sexual dimorphism (larger males in some
carnivores)and baculum size (Larivière and Fergu2
son , 2002). However , some caution is required with
this interpretation , because t he size of t he penis is not
necessarily proportional to masculine body size in
mammals. For example , in the gorilla , where silver2
back males can weigh 160 kilograms (twice the size of
the female)the penis is only 9 centimeters long
whereas in the chimpanzee (which is not markedly
sexually dimorp hic in body weight )captive males
weighing 5818 kilograms have been found to have pe2
nile lengths ranging from 10 - 18 cm (Dixson and
Mundy , 1994).
The functions of the baculum during intromis2
sion remain speculative and are worthy of further
study. They may include strengt hening of the penis ,
and protection of the urethra during extended copula2
tions (Ewer , 1973), or facilitation of sperm trans2
port (Dixson , 1987 , 1998). Although elongation of
the baculum is associated with more prolonged intro2
mission in primates and carnivores , it should not be
inferred that long bacula are essential for maintenance
of extended intromissions in mammals. Thus , the
baculum is absent in marsupials , many of which cop2
ulate for extended periods (Tyndal2Biscoe and Ren2
free , 1987). A variety of factors is likely to have con2
tributed to the evolution of longer bacula in mam2
mals. Ferguson and Larivière (2004), for example ,
have reported that longer bacula are more prevalent in
species which inhabit high latitude snowy environ2
ments.
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4期Alan DIXSON et al. : Baculum length in mammals
APPENDIX Ⅰ Adult body weight, baculum length, and residuals of baculum length for carnivores, bats and primates, together
with a classification of intromission patterns ( L = long , > 3 min; S = short; U= unknown)
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
Pinnipedia Otariidae O ta ria f la vescens 522 000 146100 01054 U
Eumetopias jubata 938 000 206100 01096 L
Zalophus calif ornianus 170 000 120100 01175 U
Neophoca cinerea 364 000 260100 01371 U
A rctocephal us t ropicalis 160 000 128100 01214 U
Callorhi nus ursinus 250 000 142100 01177 U
Odobenidae Odobenus rosm arus 124 600 0 540100 01462 U
Phocidae Phoca vitulina 104 000 137100 01322 U
Phoca hispida 43 000 118100 01419 U
Phoca f asciat a 76 000 142100 01395 U
Phoca groenlandica 140 000 185100 01398 U
Halichoerus gry pus 204 000 163100 01274 L
Erignathus barbatus 239 000 140100 01179 U
Monachus schaui nslandi 172 000 183100 01356 U
Lobodon carcinophagus 179 000 220100 01428 U
Hydrurga leptonyx 220 000 233100 01415 U
Leptonychotes weddelli 286 000 218100 01338 L
Cystophora cristata 370 000 210100 01275 U
Mi rounga leoni na 2 550 000 331100 01119 U
Mi rounga angustirostris 2 268 000 274100 01058 L
Carnivora Ursidae U rsus arctos 200 000 132100 01186 L
Ursus mariti m us 360 000 168100 01183 U
Ursus thibetanus 410 000 118120 01007 U
Ursus ursinus 120 000 151100 01338 U
Ursus malayanus 102 000 52100 - 01095 U
Ursus americanus 46 000 137100 01472 U
Procyonidae Procyon lotor 135 000 93120 01107 L
Nasua narica 5 900 77100 01598 U
Nasua nasua 9 100 77150 01522 U
Potos f la vus 11 300 68100 01425 U
Bassariscus astutus 900 30100 01534 U
Ailuridae Ai lurus f ulgens 2 050 23100 01267 U
Canidae Canis lupus 3 750 108170 01831 L
Canis f am ili aris 49 000 70100 01169 L
Canis l at rans 16 750 77100 01407 L
Canis aureus 7 300 62170 01470 U
Urocyon cinereoargenteus 3 700 61100 01583 U
Urocyon littoralis 1 950 58100 01678 U
V ul pes m acrotis 2 200 45100 01546 U
694 动 物 学 报 50 卷
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
V ul pes v ulpes 20 000 55160 01233 L
Nyctereutes procyonoides 10 300 72150 01470 L
Fennecus zerda 8 000 31100 01147 U
Alopex lagopus 3 620 59100 01572 U
Mustelidae Mustela putorius 2 000 47190 01590 U
Mustela lut reola 1 050 46100 01691 U
Mustela nivalis 1 600 18140 01216 L
Mustela erminea 118 24190 01825 L
M ustela f renat a 305 26100 01670 L
Mustela nigri pes 1 500 37100 01531 L
Mustela vison 1 523 48100 01641 L
Martes americana 860 39100 01656 L
Martes martes 233 43170 01945 L
Martes foina 1 500 60160 01745 L
Martes pennanti 4 760 100100 01751 L
Meles meles 11 600 105100 01609 L
Taxi dea t axus 6 750 88100 01631 U
Mellivora capensis 10 000 60100 01393 U
L ut ra l utra 10 100 58100 01377 L
L ut ra m aculi collis 5 250 80100 01636 U
Lont ra canadensis 9 200 66100 01450 L
L ut ragale perspicil lata 9 000 74100 01503 U
Aonyx cinerea 4 050 38100 01360 U
Pteronura brasiliensis 29 000 38100 - 01001 U
Enhydra l utris 28 300 148100 01594 L
Gulo gulo 14 800 143100 01698 L
Felidae Felis silvestris 5 500 5150 - 01535 U
Felis catus 3 500 4150 - 01539 S
Felis viverrina 11 500 5100 - 01712 U
Felis bengalensis 5 000 4150 - 01605 U
Felis serval 13 000 6100 - 01655 U
Felis lynx 15 000 6100 - 01681 U
Felis concolor 85 000 4100 - 11175 S
Felis pardalis 11 000 7100 - 01557 S
Felis canadensis 9 870 9100 - 01428 U
Felis ruf us 9 600 6100 - 01599 U
Neofelis nebulosa 22 000 4100 - 01928 U
Pant hera leo 200 000 7150 - 11059 S
Pant hera pardus 63 500 7100 - 01879 U
Pant hera tigris 235 000 12100 - 01885 S
Pant hera onca 55 000 8100 - 01795 S
794
4期Alan DIXSON et al. : Baculum length in mammals
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
Mephitidae Conepatus mesoleucus 2 168 13100 01009 U
Mephitis mephitis 2 820 21100 01169 L
Spilogale p utori us 399 20100 01507 U
Chiroptera Emballonuridae Balantioptery x io 3170 0108 - 11033 U
Balantioptery x plicat a 5190 0107 - 11176 U
Corm u ra brevi rostris 8160 0140 - 01489 U
Peroptery x kappleri 8163 0130 - 01614 U
Peroptery x m acrotis 5145 0136 - 01451 U
Rhynchonycteris naso 4124 0180 - 01058 U
Saccopteryx bilineata 7162 0157 - 01313 U
Taphozous georgianus 30100 0130 - 01843 U
Taphozous longimanus 36100 1110 - 01312 U
Megadermatidae Cardioderma cor 28197 2100 - 01012 U
Megaderma ly ra 64104 0156 - 01711 U
Molossidae Eumops bonariensis 11140 0153 - 01418 U
Eumops glauci nus 35160 0152 - 01635 U
Eumops underw oodi 56180 0151 - 01729 U
Molossus ater 39160 0132 - 01866 U
Molossus bondae 18180 0121 - 01912 U
Molossus molossus 14123 0124 - 01803 U
Molossus sinaloae 25150 0122 - 01948 U
Mormopterus pl aniceps 9150 7190 01789 U
Nycti nomops aurispi nosus 17100 0176 - 01335 U
Nycti nomops f emorosaccus 14175 0176 - 01309 U
Nycti nomops laticaudatus 12143 0161 - 01373 U
Tadarida aegyptiaca 16110 0184 - 01281 U
Tadarida brasiliensis 12180 0155 - 01423 U
Tadarida teniotis 34110 0180 - 01440 U
Mormoopidae Mormoops megalophylla 17110 1100 - 01217 U
Natalidae Natalus strami neus 5137 0163 - 01205 U
Nycteris hispi da 10193 1150 01041 U
Nycteris macrotis 16121 5100 01492 U
Nycteris thebaica 9100 2182 01351 U
Pteropodidae Acerodon celebensis 500100 8100 01067 U
Cynopterus brachyotis 31150 1183 - 01066 U
Cynopterus sphinx 37119 2108 - 01041 U
Cynopterus titthaecheileus 62100 2180 - 01006 U
Dobsonia exoleta 249100 5170 01048 U
Dobsonia minor 70100 3135 01050 U
Dobsonia moluccensis 412125 7130 01063 U
894 动 物 学 报 50 卷
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
Dobsonia pannietensis 294100 3160 - 01182 U
Eidolon dupreanum 292150 4100 - 01135 U
Eidolon helv u m 258194 4140 - 01072 U
Eonycteris spelaea 62100 3169 01114 U
Epomophorus gambianus 122130 3113 - 01082 U
Epomops f ranqueti 135195 1160 - 01393 U
Hypsignathus monst rosus 354140 2150 - 01375 U
Macroglossus mi ni mus 15113 2177 01248 U
Macroglossus sobrinus 23100 2141 01111 U
Micropteropus pusill us 32140 2110 - 01012 U
Nycti mene albiventer 29135 3180 01264 U
Nycti mene cephalotes 43120 1190 - 01108 U
Nycti mene major 100176 3180 01038 U
Pteropus admiralitatum 334100 2130 - 01400 U
Pteropus alecto 800100 9126 01045 U
Pteropus aneti anus 470100 4150 - 01171 U
Pteropus conspicillat us 811125 9115 01037 U
Pteropus giganteus 881133 6153 - 01125 U
Pteropus hypomelan us 440100 6176 01018 U
Pteropus macrotis 365100 8100 01125 U
Pteropus melanopogon 860100 9145 01040 U
Pteropus neohibernicus 1 052150 12190 01138 U
Pteropus ornatus 285100 8130 01186 U
Pteropus poliocephalus 841100 6150 - 01118 U
Pteropus rayneri 774100 5160 - 01168 U
Pteropus scapulatus 489150 10198 01209 U
Pteropus tongan us 448100 7140 01054 U
Pteropus vampyrus 1 010100 7105 - 01116 U
Rousettus aegyptiacus 151123 1120 - 01537 U
Rousettus am plexicau datus 83143 2176 - 01066 U
Rousettus leschenaulti 100100 3115 - 01042 U
Syconycteris aust ralis 17161 5160 01526 U
Rhinolophidae Asellia t ridens 12127 1147 01011 U
Coelops f rithi 7140 1195 01227 U
Hip posi deros caf f er 9108 1128 01007 U
Hipposideros cervinus 9140 0130 - 01630 U
Hipposideros cineraceus 3175 2102 01367 U
Hipposideros diadema 47100 2130 - 01040 U
Hipposideros galerit us 6150 0140 - 01437 U
Hipposideros lankadiv a 60100 3125 01065 U
Hipposideros speoris 10100 0147 - 01446 U
994
4期Alan DIXSON et al. : Baculum length in mammals
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
Rhinolophus blasii 10140 2113 01203 U
Rhinolophus clivosus 14110 3106 01304 U
Rhinolophus euryale 7190 3125 01437 U
Rhinolophus ferrumequi num 18142 4132 01405 U
Rhinolophus hipposideros 4137 3131 01553 U
Rhinolophus megaphyllus 9150 5100 01590 U
Rhinolophus mehelyi 13160 2180 01272 U
Rhinolophus rouxi 12157 2142 01224 U
Triaenops persicus 13110 2180 01279 U
Rhinopomatidae Rhinopom a hardw ickei 19100 1133 - 01112 U
Rhinopoma microphyllum 32113 1135 - 01202 U
Vespertilionidae A nt rozous du biaquerc us 21185 0182 - 01348 U
A nt rozous pal li dus 22120 1104 - 01248 U
Barbastella barbastellus 8190 0176 - 01216 U
Chalinolobus argentatus 7199 0168 - 01245 U
Chalinolobus goul dii 13150 3194 01422 U
Chalinolobus morio 8108 4129 01553 U
Chalinolobus variegatus 11123 0184 - 01215 U
Eptesicus bottae 15140 0164 - 01391 U
Eptesicus brasiliensis 8190 0178 - 01205 U
Eptesicus capensis 5140 1196 01287 U
Eptesicus f u rinalis 7153 0192 - 01103 U
Eptesicus f uscus 17173 0180 - 01320 U
Eptesicus nilssoni 10150 1132 - 01007 U
Eptesicus serotinus 18185 1110 - 01193 U
Eptesicus somalicus 3140 1154 01267 U
Eptesicus vult urnus 3140 4147 01730 U
Glischropus tylopus 3170 0181 - 01028 U
Idionycteris phyllotis 11130 1180 01115 U
L aephot is w in toni 6100 2116 01310 U
L asionyct eris n octi vag ans 9170 2176 01328 U
L asiu rus boreal is 9195 1100 - 01117 U
L asiu rus ci nereus 24107 1112 - 01230 U
L asiu rus ega 11195 0187 - 01211 U
L asiu rus i nte rme dius 17130 1127 - 01115 U
Myotis austroriparius 5190 0187 - 01082 U
Myotis bechsteini 6110 0169 - 01189 U
Myotis blythii 21190 0188 - 01318 U
Myotis capaccinii 8180 0183 - 01176 U
Myotis daubentoni 7117 0169 - 01218 U
Myotis emargi natus 7100 0161 - 01268 U
005 动 物 学 报 50 卷
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
Myotis grisescens 9195 1100 - 01117 U
Myotis keenii 6140 0180 - 01133 U
Myotis l ucif ugus 7115 1123 01033 U
Myotis myotis 22165 0198 - 01277 U
Myotis nattereri 6114 0180 - 01126 U
Myotis ri dleyi 4100 0185 - 01021 U
Myotis thysanodes 7107 0177 - 01168 U
Myotis velif er 9190 1110 - 01075 U
Nyctalus lasiopterus 45120 7180 01497 U
Nyctalus leisleri 11150 6185 01692 U
Nyctalus noctula 28150 5176 01450 U
Nycticeius balstoni 10175 2121 01213 U
Nycticeius hu meralis 7120 2138 01318 U
N ycticei us sch lief f eni 4160 4116 01643 U
N yctophi lus geoff royi 6140 2153 01367 U
Nyctophil us gouldi 8100 3127 01437 U
Nyctophil us microtis 6170 3141 01488 U
Nyctophil us timoriensis 13125 3176 01405 U
Otonycteris hem prichi 24170 2163 01136 U
Philetor brachypterus 11120 2168 01289 U
Pipistrellus bodenhei meri 2150 1165 01353 U
Pipistrellus eisent rauti 6110 1141 01122 U
Pipistrellus hesperus 3150 2149 01470 U
Pipistrellus kuhlii 5182 2119 01321 U
Pipistrellus mi m us 3160 3123 01578 U
Pipistrellus nanus 3165 1157 01262 U
Pipistrellus nathusii 7130 1133 01063 U
Pipistrellus pipist rellus 5136 1166 01216 U
Pipistrellus rueppelli 4180 7127 01878 U
Pipistrellus rusticus 4100 1191 01331 U
Pipis trell us s ubf lav us 5158 0165 - 01198 U
Pipistrellus tenuis 3130 3150 01629 U
Plecotus aurit us 7177 1106 - 01047 U
Plecotus aust riacus 6156 0176 - 01160 U
Plecot us raf i nesqu ii 9110 1100 - 01101 U
Plecotus tow nsen dii 6190 0186 - 01116 U
Rhogeesa tum ida 3150 0167 - 01100 U
Scotoecus hirundo 9125 11130 01949 U
Scotophilus borbonicus 22100 1165 - 01045 U
Scotophilus heathi 37150 1169 - 01133 U
Scotophilus leucogaster 19190 2113 01084 U
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4期Alan DIXSON et al. : Baculum length in mammals
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
Tylonycteris pachypus 4110 0145 - 01302 U
Tylonycteris robust ula 8140 0143 - 01453 U
Vespertilio m urinus 14152 1172 01049 U
Primates Lorisidae L oris t ardigradus 290 14120 01416 L
Perodicticus potto 1 002 21100 01359 U
Galago senegalensis 230 16170 01529 L
Gala goi des de mi dof f 63 13110 01661 L
Otolem ur crassicaudat us 1 290 22140 01341 L
Otolem ur garnettii 820 26100 01489 L
Cheirogaleidae Microcebus muri nus 80 11100 01542 L
Cheirogaleus medius 180 14100 01498 U
Lemuridae Eulemur catta 2 900 11150 - 01097 S
Eule mur f ul vus 2 500 9100 - 01177 U
V arecia va riegat a 3 600 12130 - 01108 S
Hapalem u r griseus 2 000 11100 - 01049 U
Indriidae Propithecus verreauxi 3 700 7160 - 01322 U
Daubentoniidae Daubentonia madagascariensis 2 800 28100 01296 L
Cebidae Aotus lem u ri nus 923 2120 - 01606 S
Cebus apella 2 860 8150 - 01226 S
Cebus capucin us 3 800 10110 - 01203 U
Saimi ri boli viensis 1 025 9100 - 01013 S
Callitrichidae Callithri x jacchus 310 2100 - 01447 S
Callit hrix argentata 357 2110 - 01452 U
Callit hrix humeralif er 300 2110 - 01420 U
Cebuella pygm aea 122 2120 - 01235 S
Saguinus oedi pus 500 1170 - 01605 S
Saguinus f uscicollis 420 1190 - 01525 S
Saguinus labiatus 460 1170 - 01590 U
Saguinus midas 600 2120 - 01527 U
Saguinus mystax 567 1160 - 01655 U
Saguinus ni gricollis 470 1160 - 01620 U
Saguinus bicolor 430 2140 - 01428 U
Leontopit hecus rosalia 560 3100 - 01379 S
Callimico goeldii 450 1180 - 01561 S
Cercopithecidae Presbytis comata 6 390 6170 - 01477 U
Trachypit hecus vet ulus 7 550 12150 - 01237 U
Nasalis larvat us 20 300 7190 - 01617 S
Pygat hrix nemaeus 10 900 15130 - 01216 U
Colobus guereza 11 800 12140 - 01322 U
Colobus polykomos 9 900 14120 - 01231 U
205 动 物 学 报 50 卷
Order Family Species Body weight
(grams)
Baculum length
(mm)
Residual baculum
length
Intromission
pattern
Colobus badi us 10 500 13130 - 01270 S
Procolobus verus 4 700 9180 - 01255 U
Chlorocebus aethiops 4 750 16150 - 01031 S
Cercopithecus mitis 7 600 16130 - 01123 U
Cercopithecus mona 4 400 23170 01140 U
Cercopithecus neglectus 7 000 17170 - 01072 U
Miopithecus talapoin 1 400 9150 - 01047 S
Erythrocebus patas 10 000 15180 - 01186 S
Lophocebus albigena 9 000 21120 - 01039 S
Cercocebus torquat us 10 750 14130 - 01243 U
Mandrillus sphinx 26 900 24180 - 01172 S
Mandrillus leucophaeus 1 700 21100 01262 S
Papio anubis 21 000 30100 - 01044 S
Papio cy nocephal us 20 000 22150 - 01160 S
Papio ham adryas 21 500 21160 - 01191 S
Papio papio 17 600 22100 - 01146 U
Papio u rsinus 20 400 26120 - 01098 S
Theropit hecus gelada 20 500 26100 - 01102 S
Macaca nemestrina 10 400 21170 - 01056 S
Macaca nigra 10 400 23180 - 01016 S
M acaca f ascicularis 5 900 13110 - 01171 S
Macaca mulatt a 11 200 17100 - 01175 S
Macaca f uscata 11 700 19100 - 01135 S
Macaca assamensis 11 450 25180 01002 U
Macaca sinica 6 500 20100 - 01005 S
Macaca thibetana 19 200 24140 - 01117 S
Macaca arctoides 10 050 53110 01339 L
Hylobatidae Hylobates lar 5 700 8150 - 01353 U
Pongidae Pongo py gmaeus 70 000 13155 - 01610 L
Pan troglodytes 41 600 6190 - 01808 S
Pan paniscus 45 000 8150 - 01731 S
Gorilla gorilla 160 000 12160 - 01793 S
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4期Alan DIXSON et al. : Baculum length in mammals
