A survey of small mammals was made in a tree plantation in Sabah, East Malaysia. Transects within pure plantings of Eucalyptus deglupta, Gmelina arborea, Albizia falcataria, and A. falcataria/Theobroma cacao were compared with a similar transect laid through seven-year-old logged forest near the plantation. A total of 16 small mammal species were trapped, with 11 found in the logged forest area, and 15 in the plantation. Values for the Shannon-Wiener Diversity Index (H') and for biomass were highest in logged forest, which also showed a low (<45%) Percent Similarity when compared with any of the plantation areas. Highest diversity and biomass values within the plantation were found in Albizia falcataria plantings, while the lowest were found in A. falcataria underplanted with Theobroma cacao. All plantation areas were dominated by Maxomys whiteheads, whereas A. falcataria plantings had the highest numbers of Tupaia glis and Tupaia tana.

The study shows that although tropical plantations of exotic tree species can support a large number of species of scansorial small mammals, overall diversity and species biomass per hectare is much lower than that found in logged forest.

The grasping behaviour, locomotion and substrate use of the tree shrews Tupaia minor and T. tana were investigated in the Department of Zoological Research at the National Zoological Park in Washington, DC. Seven arboreal T. minor and five terrestrial T. tana were observed and videotaped for 10-min focal animal samples totalling 77 h of observation. Locomotion and substrate use were scored and images of grasping behaviour were captured from videotapes. Tupaia minor individuals were videotaped crossing dowels and the number of dowel crossings that included grasps were scored. In 84% of dowel crossings, T. minor individuals used either their hallux or their pollex to grasp the dowels. Tupaia minor was also more active, moved more quickly, was more arboreal, rooted less, reversed its feet more, flexed its forelimbs more and was more semi-plantigrade than T. tana. It is proposed that arboreal tupaiids, such as Ptilocercus lowii and T. minor, may represent better models for early primates than didelphid marsupials because they are capable of grasping and are more closely related to primates.