An oft-cited nutritional advantage of large body size is that larger animals have lower relative energy requirements and that, due to their increased gastrointestinal tract (GIT) capacity, they achieve longer ingesta passage rates, which allows them to use forage of lower quality. However, the fermentation of plant material cannot be optimized endlessly; there is a time when plant fibre is totally fermented, and another when energy losses due to methanogenic bacteria become punitive.
Three new ciliate species presumed to belong to the family Paraisotrichidae were recovered from faecal samples from Asian and African elephants (Elephas maximus and Loxodonta africana) in Kiev, Moscow and Warsaw zoos. As all the ciliates have a unique but similar arrangement of somatic ciliature, a new genus Latteuria gen. nov. was erected. The genus is characterized by the presence of a tapered frontal "spout" at the anterior end of the body, posterior ciliary rows in narrow grooves encircling the posterior half of the body and an anterior arch of cilia. L.
The management of tropical forest in timber concessions has been proposed as a solution to prevent further biodiversity loss. The effectiveness of this strategy will likely depend on species-specific, population-level responses to logging. We conducted a survey (749 line transects over 3450 km) in logging concessions (1.2 million ha) in the northern Republic of Congo to examine the impact of logging on large mammal populations, including endangered species such as the elephant (Loxodonta africana), gorilla (Gorilla gorilla), chimpanzee (Pan troglodytes), and bongo (Tragelaphus eurycerus…
Hierarchical properties characterize elephant fission-fusion social organization whereby stable groups of individuals coalesce into higher order groups or split in a predictable manner. This hierarchical complexity is rare among animals and, as such, an examination of the factors driving its emergence offers unique insight into the evolution of social behaviour.
Chemokine receptors (CCRs) play an essential role in the initiation of an innate immune host response. Several of these receptors have been shown to modulate the outcome of viral infections. The recent availability of complete genome sequences from a number of species provides a unique opportunity to analyze the evolution of the CCR genes. A phylogenetic analysis revealed that the CCR2 gene evolved in concert with the paralogous CCR5 gene, but not with another paralogous gene, CCR3, in the opossum, platypus, rabbit, guinea pig, cat, and rodent lineages.