Publications by authors named "Kalsum M Yusah"

Article Synopsis
  • Logged and disturbed forests, often seen as degraded, actually harbor significant biodiversity and should not be dismissed in conservation efforts.
  • A study in Sabah, Malaysia examined the effects of logging intensity on 1,681 species, revealing two important conservation thresholds.
  • Lightly logged forests (less than 29% biomass removed) can recover well, while heavily degraded forests (over 68% biomass removed) may need more intensive recovery efforts, highlighting the varying conservation values of logged forests.
View Article and Find Full Text PDF

Asian weaver ants () are an important biocontrol agent in agricultural habitats. We conducted surveys in oil palm plantations in Riau, Indonesia for an obligate myrmecophilous butterfly larvae, (Lepidoptera, Lycaenidae), that is known to consume weaver ant larvae in other habitat types. We found larvae in five of the twenty nests surveyed, with larval presence not being related to weaver ant nest size.

View Article and Find Full Text PDF

Fungal pathogens are implicated in driving tropical plant diversity by facilitating strong, negative density-dependent mortality of conspecific seedlings (C-NDD). Assessment of the role of fungal pathogens in mediating coexistence derives from relatively few tree species and predominantly the Neotropics, limiting our understanding of their role in maintaining hyper-diversity in many tropical forests. A key question is whether fungal pathogen-mediated C-NDD seedling mortality is ubiquitous across diverse plant communities.

View Article and Find Full Text PDF

Background: Competitive interactions in biological communities can be thought of as giving rise to "assembly rules" that dictate the species that are able to co-exist. Ant communities in tropical canopies often display a particular pattern, an "ant mosaic", in which competition between dominant ant species results in a patchwork of mutually exclusive territories. Although ant mosaics have been well-documented in plantation landscapes, their presence in pristine tropical forests remained contentious until recently.

View Article and Find Full Text PDF
Article Synopsis
  • Invertebrates like termites, ants, and beetles are super important in tropical rainforests because they help keep the ecosystem healthy and strong.
  • Logging (cutting down trees) has harmed more than one-third of these forests, reducing the number of invertebrates by up to half, which affects how the forest works.
  • Even though some other animals like small mammals and certain birds may increase after logging, the decline of important invertebrates shows that humans are changing how these rainforests operate.
View Article and Find Full Text PDF

Understanding how species assemble into communities is a key goal in ecology. However, assembly rules are rarely tested experimentally, and their ability to shape real communities is poorly known. We surveyed a diverse community of epiphyte-dwelling ants and found that similar-sized species co-occurred less often than expected.

View Article and Find Full Text PDF

Anthropogenic disturbance and the spread of non-native species disrupt natural communities, but also create novel interactions between species. By-product mutualisms, in which benefits accrue as side effects of partner behaviour or morphology, are often non-specific and hence may persist in novel ecosystems. We tested this hypothesis for a two-way by-product mutualism between epiphytic ferns and their ant inhabitants in the Bornean rain forest, in which ants gain housing in root-masses while ferns gain protection from herbivores.

View Article and Find Full Text PDF

Flies in the family Milichiidae are often myrmecophilic. We document the first record of a fly from this family interacting with an ant of the genus Polyrhachis. In lowland riparian rainforest in Sabah, Malaysia, we observed a female of the genus Milichia following an ant of the species of P.

View Article and Find Full Text PDF

The conversion of natural forest to oil palm plantation is a major current threat to the conservation of biodiversity in South East Asia. Most animal taxa decrease in both species richness and abundance on conversion of forest to oil palm, and there is usually a severe loss of forest species. The extent of loss varies significantly across both different taxa and different microhabitats within the oil palm habitat.

View Article and Find Full Text PDF

Specialized parasites are expected to express complex adaptations to their hosts. Manipulation of host behavior is such an adaptation. We studied the fungus Ophiocordyceps unilateralis, a locally specialized parasite of arboreal Camponotus leonardi ants.

View Article and Find Full Text PDF