Asian Myrmecology, Volume 2, pages 33-49, published December 2008
An analysis of declining ant species richness with increasing elevation at Mount Kinabalu, Sabah, Borneo
ANNETTE K.F. MALSCH1*, BRIGITTE FIALA2, ULRICH MASCHWITZ1, MARYATI MOHAMED3, JAMILI NAIS4 & K. EDUARD LINSENMAIR2
1J.W. Goethe-University Frankfurt, Institute of Zoology, Department of Ethoecology, 60054 Frankfurt, Germany
2Animal Ecology and Tropical Biology (Zoology III), Biozentrum, Julius-Maximilian-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
3 Universiti Malaysia Sabah, Institute for Tropical Biology and Conservation, Post Box 2073, 88999 Kota Kinabalu, Sabah, Malaysia
4Sabah Parks, Post Box 10626, 88806 Kota Kinabalu, Sabah, Malaysia
© A.K.F. Malsch, B. Fiala, U. Maschwitz, M. Mohamed, J. Nais & K. E. Linsenmair
Abstract. This study investigated factors responsible for the decline of ant species
richness with increasing elevation in an evergreen tropical rain forest on Mount
Kinabalu. From 580 m to 1520 m a.s.l. we studied the ant community as well as biotic
and abiotic factors in parallel on the ground and in the lower vegetation with various
methods. We collected a total of 376 ant morphospecies, belonging to 65 genera and
8 subfamilies. The decline of ant species richness was significantly correlated with
the decline in temperature but the pattern of decline differed between the two strata.
In contrast the ant nest density remained the same on the ground and in the lower
vegetation up to 1000 m, but then dropped significantly. As the main nesting resource
(dead wood) remained rather constant over the elevation gradient, the most plausible
explanation is a direct impact of temperature. In addition, the increasing compaction
of the soil and increased depth of the humus layer also restricts nesting on the
ground at the highest elevations. A case study of the ground ant Diacamma sp.
along the elevation gradient indicated scarcity of food as another important factor in
the ground layer uphill.
Keywords: elevational gradient, ants, Malaysia, Kinabalu, species richness, temperature, tropical diversity