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Schismatoglottis clivemarshii and Schismatoglottis priapica are described and illustrated as new species from the Danum Valley Conservation Area, Tawau, Lahad Datu, Sabah, to where both are endemic. [ABSTRACT FROM AUTHOR]

Bucephalandra danumensis is described from the Danum Valley Conservation Area, Tawau, Lahad Datu, Sabah, where it is restricted to streams and waterfalls on igneous outcrops in forests on Cretaceous deepwater sediments, and compared with the only other Sabahan Bucephalandra species, and with all species with echinate/papillate spadix appendix staminodes. Recognition of B. danumensis takes Bucephalandra to 31 described species, of which just two, both endemic, are known from Sabah. Both Bucephalandra species from Sabah are illustrated from living plants, and a comparative plate of the spadix of all species with echinate/papillate appendix staminodes is provided. [ABSTRACT FROM AUTHOR]

Understanding whether the long and elaborate songs of male gibbons (Hylobates muelleri) have syntax and hierarchical structures (chunks) is an interesting question in the evolution of language, because gibbons are near humans in the phylogenetic tree and a hierarchically organized syntax is considered to be a basic component of human language. We conducted field research at Danum Valley Conservation Area in northern Borneo to test the hypothesis that gibbon songs have syntax and chunks. We followed one Mueller's gibbon group for 1 week in the dry and rainy seasons every year from 2001 to 2009, collecting vocal and behavioral data. Results show that songs emitted by the studied male gibbon were governed by combinatory rules. Some context-dependent songs had different combinatory rules, although they overlapped with the songs whose contexts were uncertain. The male Mueller's songs had characteristics that suggest existence of chunk structure. These results provided an important perspective in the study of language origin. [ABSTRACT FROM AUTHOR]

Activity budget, travel distance, sleeping time and height of activity of two wild East Bornean grey gibbon (Hylobates funereus) groups and travel order of one group were investigated during the dry and wet season at the Danum Valley Conservation Area, Sabah, Malaysia. One male showed seasonal change in his behaviors between the dry season (August) and wet season (December). He spent more time engaged in moving, playing and grooming, traveled longer and entered the sleeping tree later in the dry season when fruit was abundant but did the opposite in wet season. On the other hand, another male gibbon whose family had a new-born baby did not show a similar seasonal behavioural change between the dry season (May-June) and wet season (December). Fruit availability and gibbon family composition, especially whether the family had a new-born baby, may have an influence on the activity budget, movement and sleeping time of East Bornean grey gibbons. Early night-tree entry may be influenced by combined factors such as fruit availability, predator avoidance and fruit competition with other animals. The female gibbon's activities occurred at greater height above the ground compared to that of males in the early morning and the late afternoon. Similar to other gibbons, the female East Bornean grey gibbon led the group more often than the male. In addition, a rare observation was made of infant carrying by the adult male when the infant was 29 months old. [ABSTRACT FROM AUTHOR]

A correction to the article "Fallback Foods of Red Leaf Monkeys (Presbytis rubicunda) in Danum Valley, Borneo" by Goro Hanya and Henry Bernard in the previous issue is presented.

Increases in the frequency of large to extreme rainfall events are widely predicted with global warming, but evidence from the humid tropics is hampered by a paucity of long-term data. This paper assesses changes in daily rainfall magnitude–frequency and their geomorphological consequences in the equatorial environment of northern Borneo using (1) rare daily rainfall data series for 1906–2012 assembled from archival and current sources and (2) geomorphological process data from the Danum Valley area of eastern Sabah. Rainstorm changes are explored using (1) analysis of frequencies of daily falls above threshold values, (2) extreme-value analysis comparing differences in locally weighted scatterplot smoothing (LOESS) best-fit curves for successive 20-year periods and (3) a novel approach constructing graphs of long-term change in daily falls of 1- to 10-year return period derived from overlapping 20-year LOESS curves. Substantial increases, some statistically significant, since 1980 (intensifying since 1999) are detected at most stations in (1) the frequency of daily falls ≥50, 100 and 200 mm and (2) the magnitudes of daily falls with return periods of 0.2–5.0 years. The scale and temporal patterns of historical change vary with (1) coastal aspect and (2) different parts of the return period spectrum. The period 1921–1940 exhibited higher rainstorm magnitude–frequency than 1952–1979 and demonstrates the dangers of simple deductions derived from post-1960 data comparisons. Geomorphological responses indicated by long-term monitoring at Danum (eastern Sabah), where there has been a marked upswing in heavy rainfalls since 1999, include a threefold increase in slopewash rates, more frequent high flows and higher sediment loads. The very high soil pipe sediment yields, rates of pipe roof collapse and stream channel extension recorded from 2002 to 2012 in pipe systems at Danum may be a consequence of this upswing. Increased landsliding is also a likely consequence, exacerbated in logged, agricultural and urban terrain. [ABSTRACT FROM AUTHOR]

Animals in Southeast Asia must cope with long periods of fruit scarcity of unpredictable duration between irregular mast fruiting events. Long-term data are necessary to examine the effect of mast fruiting on diet, and particularly on the selection of fallback foods during periods of fruit scarcity. No such data is available for colobine monkeys, which may consume substantial amounts of fruits and seeds when available. We studied the diet of red leaf monkeys ( Presbytis rubicunda, Colobinae) in Danum Valley, Sabah, northern Borneo, using 25 mo of behavioral observation, phenology and vegetation surveys, and chemical analysis to compare leaves eaten with nonfood leaves. The monkeys spent 46% of their feeding time on young leaves, 38% on seeds, 12% on whole fruits, 2.0% on flowers, 1.0% on bark, and 1.2% on pith. They spent more time feeding on seeds and whole fruit when fruit availability was high and fed on young leaves of Spatholobus macropterus (liana, Leguminosae) as fallback foods. This species was by far the most important food, constituting 27.9% of the total feeding time, and the feeding time on this species negatively correlated with fruit availability. Consumed leaves contained more protein than nonconsumed leaves, and variation in time spent feeding on different leaves was explained by their abundance. These results suggest that red leaf monkeys show essentially the same response to the supra-annual increase in fruit availability as sympatric monogastric primates, increasing their seed and whole-fruit consumption. However, they depended more on young leaves, in particular Spatholobus macropterus, as fallback foods during fruit-scarce periods than did gibbons or orangutans. Their selection of fallback food appeared to be due to both nutrition and abundance. [ABSTRACT FROM AUTHOR]

The article reports on the discovery of the new bird specie, "Spectacled Flowerpecker," near the Borneo Rainforest Lodge in the Danum Valley of Malaysia's Sabah province. University of Leeds biologist Richard Webster and two leaders from the tour company Field Guides found a pair of this species on June 18, 2009. Webster consulted Leeds University Fellow David Edwards about the species. They joined Rose Ann Rowlett to further observe the species and discovered at least two of the birds feeding on the mistletoe.