474 
PACIFIC SCIENCE, VoE XX, October 1966 
TABLE 1 
Rectal Temperatures of 23 Species of Malaysian Rain Forest Mammals* 
SPECIES NAME 
NO. OF 
INDI- 
VIDUALS 
NO. OF 
TEMP. 
READINGS 
TEMPERATURE 
RANGE 
MEAN ±95% 
CONF. LIMITS 
COEFFICIENT 
OF 
VARIABILITY 
Insectivora 
Erinaceidae 
Hylomys suillus 
14 
34 
33.6-38.1 
36.11 ± 0.35 
2.79 
Echinosorex gymnura 
2 
2 
28.1-32.3 
30.20 
— 
Chiroptera 
Pteropidae 
Cynopterus brachyotis 
3 
3 
34.0-36.3 
35.33 
— 
V espertilionidae 
Tylonycteris robust ula 
9 
9 
34.3-38.4 
36.64 
— 
Primates 
Tupaiidae 
Tupaia glis 
4 
9 
35.8-39.2 
37.50 
— 
Tupaia minor 
2 
2 
39.1,39.1 
39.1 
— 
Lorisidae 
Nycticebus coucang 
1 
1 
34.9 
34.9 
— 
Rodentia 
Sciuridae 
Callosciurus can/ceps 
4 
4 
40.1-41.4 
40.65 
• — 
Callosciurus notatus 
6 
6 
35.8-41.2 
38.58 
— 
Callosciurus nigrovittatus 
1 
2 
40.1;40.9 
40.50 
— 
Sundasciurus tenuis 
10 
12 
36.6-42.1 
39.44 ± 1.13 
4.59 
Rhizomyidae 
Rhizomys sumatrensis 
1 
1 
36.1 
36.1 
■ — 
Muridae 
Rattus annandalei 
2 
12 
36.1-38.2 
37.10 ± 0.63 
1.76 
Rattus muelleri 
26 
79 
34.5-39.2 
37.04 ± 0.28 
3.53 
Rattus sabanus 
157 
670 
33.7-39.4 
36.54 ± 0.53 
7.61 
Rattus rajah 
21 
86 
35.1-39.6 
37.25 ± 0.58 
7.32 
Rattus surifer 
55 
138 
34.4-39.3 
37.40 ± 0.32 
5.32 
Rattus jalorensis 
6 
6 
34.8-38.2 
36.80 
— 
Rattus cremoriventer 
9 
16 
36.2-39.7 
38.20 ± 0.40 
1.97 
Rattus whiteheadi 
19 
36 
35.8-39-2 
37.91 ± 0.28 
2.34 
Rattus edwardsii 
4 
20 
34.6-38.2 
36.22 ± 0.48 
2.89 
Rattus bower si 
6 
8 
34.2-37.5 
35.87 
■ — 
Chiropodomys gliroides 
21 
32 
35.9-39-1 
37.80 ± 0.35 
2.59 
* Scientific names follow Harrison and Traub (1950) and Medway (Mammals of Borneo, in press). 
ever, throughout the majority of the period 
there was no other evidence of breeding. There- 
fore temperature readings recorded herein have 
to be considered applicable to nonbreeding ani- 
mals. 
Sexual differences in temperature were gen- 
erally very small and were concluded to be in- 
significant. For this reason no sexual separa- 
tions are made in Table 1. Curiously, however, 
in the sibling species pair, Rattus rajah and R. 
surifer, females consistently showed higher tem- 
peratures. In R. rajah mean temperatures of 
females were 1.3° higher than males; in R. 
surifer 0.5° higher. There is no ready explana- 
tion for these differences. 
Relation of temperature to body weight 
Irving and Krog (1954), Morrison and 
Ryser (1952), and Scholander et al. (1950) 
effectively show that mammalian body tempera- 
ture bears no primary relationship to body 
weight. Rather consistent differences in tem- 
