34 research outputs found
The land and the mangrove snail fauna of the islands of Banggi and Balambangan (Mollusca: Gastropoda)
We studied land and mangrove snails at four sites (three of which were limestone outcrops) on the islands of Balambangan and Banggi, within the proposed Tim Mustapha Marine Park. Both locations have island faunas with a moderate number of species: we found a total of 56 true land snail species, plus 11 intertidal Ellobiidae and Truncatellidae. Of the 56 land snails, at least six are short-range endemics of the Kudat-Banggi-Balambangan-Balabac-Palawan region. In addition, several other species that occur here are rare or threatened. We conclude that the limestone outcrops of Banggi and Balambangan are essential to the survival of at least 12 Malaysian land snail species. In view of uncontrolled logging and possibility of planned mining of limestone, we highly recommend conserving limestone outcrops of both Banggi and Balambangan as part of land-based degradation prevention at the proposed Tun Mustapha Marine Park
The Preliminary Survey of Avifauna in Gaya Island, Sabah, Malaysia
To date, there is no updated information of the status of avifauna in Gaya Island. We have conducted a preliminary survey of birds in Gaya Island with the aim to initiate and verify the data of avifauna in Gaya Island that was published 38 years ago. A six days survey was conducted from 28 June to 3 July 2013. The main method used was mist netting. Incidental sightings of bird’s species were also recorded. Three existing trails were chosen for the survey. Four mist-nets station at 50m apart were established at each trail. The total sampling effort for mist netting for the whole survey was 45 hours. A total number of 10 species of birds from 7 families were recorded in this study. 5 families and 7 species were captured with mist-nets. The majority of the species collected are from the family of Pycnonotiidae. The result of this preliminary survey provides a general view of the communities of birds in Gaya Island
Susceptibility of tropical mountain forests to biological invasions from the temperate and subtropical zone, exemplified by <i>Zonitoides</i> (Gastropoda: Gastrodontidae)
Colonisation by, and spread of, animal species from the temperate zone are rather uncommon observations in the tropics. The study provides the first reports of two snail species of the genus Zonitoides in Sabah, Borneo, namely Z. arboreus (Say, 1819) and Z. nitidus (O.F. Muller, 1774). The identification was aided using partial sequences of 28S rDNA, and the barcoding sequence of COI. So far, the two Zonitoides species were found in locations where the natural forest cover had been disturbed, and only in the montane forest at elevations between 1500 and 2000 m a.s.l.. Niche modeling suggests that both taxa could be widely distributed in the mountains of tropical South America and Africa. Z. arboreus finds suitable climates in many places in SE Asia and especially at many conservation areas in Borneo. In contrast, Z. nitidus finds only marginal climatic conditions in the same area, and introductions of Z. nitidus probably will remain spatially restricted. This prediction, however, needs to be monitored because the latter species can display molluscivory. Our results additionally point to the possibility of Z. arboreus being a species complex that, given its potential economic impact, urgently needs a taxonomic revision.</p
A Preliminary Survey on the Effect of Anthropogenic Noise to Bird Community in Gaya Island
To date, there is still scarce study that has been done looking on the impact of the anthropogenic noise in influencing the bird community in Gaya Island as it acts as an important indicator for the health of the island’s ecosystem. Hence, this preliminary study aims to determine the effect of the anthropogenic noise on the bird community in Gaya Island. The data collection was conducted for three months in three of the selected sites within the island. The methods that were being used were the point count sampling and noise mapping respectively. The anthropogenic noise level that was being measured at the selected sites ranges from 29dB to 80dB. Meanwhile, descriptive analysis, diversity indexes and correlation analysis were used to analyze the obtained data. A total of 422 individuals from 24 species and 16 families were recorded during the survey in Gaya Island. The result of the Shannon Wiener index showed that the diversity of the birds in low anthropogenic noise zone is slightly higher (H’=2.559) as compared to the bird in high anthropogenic noise zone (H’= 2.558) even though there is no significant different in terms of diversity of birds between these two zones. However, the Spearman’s correlation analysis showed a very significant and negative correlation of the anthropogenic noise with the abundance and species richness of bird (r= -0.076, p=0.000). Therefore, this study shows that the bird community is negatively affected with the increasing of anthropogenic noise in Gaya Island
Activity Patterns and Habitat Use of \u3cem\u3eAnsonia hanitschi\u3c/em\u3e on Gunung Kinabalu, Sabah, Malaysia
Ansonia hanitschi is a small, stream-breeding toad endemic to Borneo. Little is known about its ecology or behavior. We documented diurnal activity patterns and habitat use, nocturnal habitat use, and body sizes of A. hanitschi near streams and in forests on Gunung Kinabalu, Sabah, Malaysia, on the island of Borneo. We identified 12 unique diurnal behaviors in this species. Ansonia hanitschi are sit-and-wait predators that spend \u3e 75% of their time during the day, on average, sitting inactive in shady areas within 1.2 m of the stream. Observed toads spent 6% of their time jumping, 4% of their time crawling, and 4% of their time engaging in an arm waving behavior. During the day, individuals were more commonly found on smaller sand and cobble substrates. At night, individuals rested on the leaves of slender-stemmed plants within 2 m of the ground surface and at a mean distance of 2.3 m from the stream edge. Female snout-vent length averaged 32 mm, and gravid females ranged from 28 to 35 mm in length. We found that 88% of females near the stream during the day were gravid, compared with 80% of females away from streams at night. Our observations indicate that this species is diurnal and retreats to the leaves of small plants at night, possibly to avoid predation
Phylogenetic position of Tarsius bancanus based on partial Cytochrome b DNA Sequences
This study was carried out to ascertain the molecular phylogenetic position of Tarsius bancanus among Malaysian primates based on the partial of Cytochrome b (cyt b) gene sequences. A total of five samples of Tarsius bancanus from Sabah, Malaysia, were used in this study. Several other Malaysian primates were also included in the analysis (Leaf monkeys (Presbytis and Trachypithecus), Macaques (Macaca), Siamang (Symphalangus) and Slow loris (Nycticebus). We also included DNA sequences of several prosimians (Galago, Cheirogaleus, Daubentonia, Indri, Avahi, Lemur and Lepilemur) from GenBank. In addition, one individual of orang utan (Pongo pygmaeus) and human (Homo sapiens) were used as outgroups to root the tree. All taxa were analysed using character method (Maximum Parsimony, MP) and distance method (Neighbor-Joining, NJ). From the 375 examined characters, 43.2% were constant characters while 4.8% characters were parsimony uninformative whereas 52.0% characters were parsimony informative. Tree topologies discriminated three major clades in which primitive primates, Old World Monkeys and Anthropoids belongs to their own monophyletic clades. Both MP and NJ trees showed that T. bancanus was placed in primitive primates group
Phylogenetic relationships of leaf monkeys (Presbytis; Colobinae) based on cytochrome b and 12S rRNA genes
Little is known about the classification and phylogenetic relationships of the leaf monkeys (Presbytis). We analyzed mitochondrial DNA sequences of cytochrome b (Cyt b) and 12S rRNA to determine the phylogenetic relationships of the genus Presbytis. Gene fragments of 388 and 371 bp of Cyt b and 12S rRNA, respectively, were sequenced from samples of Presbytis melalophos (subspecies femoralis, siamensis, robinsoni, and chrysomelas), P. rubicunda and P. hosei. The genus Trachypithecus (Cercopithecidae) was used as an outgroup. The Cyt b NJ and MP phylogeny trees showed P. m. chrysomelas to be the most primitive, followed by P. hosei, whereas 12S rRNA tree topology only indicated that these two species have close relationships with the other members of the genus. In our analysis, chrysomelas, previously classified as a subspecies of P. melalophos, was not included in either the P. m. femoralis clade or the P. m. siamensis clade. Whether or not there should be a separation at the species level remains to be clarified. The tree topologies also showed that P. m. siamensis is paraphyletic with P. m. robinsoni, and P. m. femoralis with P. rubicunda, in two different clades. Cyt b and 12S rRNA are good gene candidates for the study of phylogenetic relationships at the species level. However, the systematic relationships of some subspecies in this genus remain unclear
New Species of Anomochilus from Borneo (Squamata: Anomochilidae)
A new species of Anomochilus is described from Gunung Kinabalu Park, Sabah, Malaysia (Borneo). The new species is diagnosed from the only two other known species in the genus by the combination of the following character states: SVL to 509 mm; an azygous parietofrontal; paravertebrals 269; transverse body rows 17 : 19 : 17; midventrals 258–261; subcaudals 7–8; dorsum unpatterned dark brown, except for pale flecks, one scale wide, on paravertebral region; large pale blotches absent on dorsum; flanks
without light line; and a pair of large pale blotches present on either side of venter. A dichotomous
identification key to the three currently known species of Anomochilus is provided. With three species of
Anomochilus known for Borneo, the island is the center of diversification of this genus of presumably
fossorial and cryptozoic snakes
A genome-wide assessment of stages of elevational parapatry in Bornean passerine birds reveals no introgression: implications for processes and patterns of speciation
Topographically complex regions often contain the close juxtaposition of closely related species along elevational gradients. The evolutionary causes of these elevational replacements, and thus the origin and maintenance of a large portion of species diversity along elevational gradients, are usually unclear because ecological differentiation along a gradient or secondary contact following allopatric diversification can produce the same pattern. We used reduced representation genomic sequencing to assess genetic relationships and gene flow between three parapatric pairs of closely related songbird taxa (Arachnothera spiderhunters, Chloropsis leafbirds, and Enicurus forktails) along an elevational gradient in Borneo. Each taxon pair presents a different elevational range distribution across the island, yet results were uniform: little or no gene flow was detected in any pairwise comparisons. These results are congruent with an allopatric “species-pump” model for generation of species diversity and elevational parapatry of congeners on Borneo, rather than in situ generation of species by “ecological speciation” along an elevational gradient