Dept. of Biological Sciences, National University of Singapore
PhD Defense Seminar cum Oral Examination
“Contest and post-contest behaviour of mangrove crab Perisesarma eumolpe (Crustacea: Sesarmidae), and the vibro-acoustic communication of Parasesarma and Perisesarma species.”
By Chen Zijian Paul
Supervisor: Professor Ng Kee Lin, Peter
Mon 07 Sep 2015: 10.00am
@ DBS Conference Room (S3, Level 5,#05-02)
All are welcome
Abstract – Fighting in animals, though an effective means to gain access to limited resources, often incurs high cost on individuals. Thus, fights often involve strategies at different stages of the contest, to avoid any unnecessary cost accrual. In Perisesarma eumolpe — a species of mangrove crab — contests are sometimes followed by stridulatory events with the rubbing of specialised structures found on the chelae. These structures, characteristic to the genera Parasesarma and Perisesarma, are known to be species-specific. This thesis attempts to answer the following questions:
- Is stridulation also present among other species of crabs of the genera, Parasesarma and Perisesarma?
- Is stridulation a cost-mitigating strategy in Pe. eumolpe contests?
- If so, how does stridulation reduce the cost involved in conflict resolution?
- Which assessment strategy does P. eumolpe employ to avoid protracted contest?
To begin, the prevalence of stridulatory behaviour in two other related species, P. fasciatum and Parasesarma ungulatum were investigated. Observation of intra-specific interactions showed that these species also use the structures on their chelae to stridulate. Although the stridulatory frequency spectra were similar, the signals obtained from all three species were markedly different in their temporal features.
Stridulation in P. eumolpe was dubbed by M.W.F. Tweedie as “a gesture of defiance and triumph”. In P. eumolpe, this is hypothesized as a post-contest cost-mitigating strategy—more specially a victory display. Evaluation of P. eumolpe stridulation against the three established criteria of victory display supports this hypothesis.
In P. eumolpe, stridulation was never observed in other contexts except to assert victory. While it is uncertain how victory displays actually mitigate the cost of fighting, two possible functions have been suggested: to advertise recent victory to nearby eavesdroppers or deter recent losers from future contest. Empirical support for these purported functions is generally lacking.
While some evidence has been provided for the advertising function of victory display, no study has yet supported the browbeating function of victory display. To investigate this function, the influence of stridulation on losers was examined. The results suggest that stridulation deterred losers from starting a new fight. While mainly observational, this is probably the first empirical work that supports the browbeating function of victory display in animals.
While future fights could be averted by a stridulatory victory display, how does P. eumolpe avoid drawing-out a current contest? The two main strategies animals have evolved to prevent protracted fighting are self and mutual assessments. However, distinguishing between these assessments has not been easy. Studies examining contest assessment of various animals have yielded findings that are not consistent with the predictions of either assessment type. The mismeasure of resource holding potential (RHP) in relation to contest duration is a potential cause of the inconsistency.
In this study, contest behaviours were the only trait that predicted contest outcome and contest duration. Thus, they were used to evaluate the contest assessment strategy of P. eumolpe. The fights of P. eumolpe were consistent with the predictions of the cumulative assessment model (CAM), a self assessment contest model.
Department of Biological Sciences,
National University of Singapore
“Payments for ecosystem services and their impacts on social equity”
Francesca Louise Mcgrath
Supervisor: Asst Prof Carrasco T L Roman
Wed 26 Aug 2015: 11.00 am
Conference Room-II (S1-03 Mezzanine)
All are welcome
Abstract: Payments for Ecosystem (or Environmental) Services (PES) schemes, a form of market-based conservation, are an established method of using incentives to compensate individuals for the provision of goods and services provided through conservation of the environment. Internationally, many PES schemes are being implemented as a way of conserving ecosystems at a variety of spatial/temporal scales across a breadth of developed and developing nations. PES schemes have been proposed as a win-win situation where environmental conservation can be coupled with poverty alleviation to produce positive outcomes for both of these factions. More recent PES scheme research has focused on the concept of equity within these schemes, building on existing literature on environmental justice. Ignoring equity within a PES scheme can lead to unintended negative impacts on the actors within the scheme which can undermine the schemes environmental objectives.
The aim of this PhD is to explore the mechanisms (social, spatial, institutional, etc) influencing equity outcomes to better inform PES scheme design and implementation. My first chapter is a meta-analysis looking into the factors associated with equity in PES schemes. Specifically analyzing scheme characteristics found in the case studies against the factors of equity. Chapter two is an analysis into PES scheme participants’ perception of fairness and how this can produce social disruptions within a community, using a case study from Sumberjaya, Indonesia. Chapter 3 will incorporate distributive equity into a land-use change agent-based model, by creating different inequitable payment scenarios. Chapter 4 will then be an application of this model to a PES scheme site in Lantapan, Philippines to see how these different inequitable payment scenarios can influence community behavior and the subsequent impacts on land-use change.”
Claire Clements from Beach House Pictures who made Wild City is looking for a couple of interns for their latest wildlife documentary filmed here in Singapore about Singapore’s wildlife. She says,
Beach House Pictures is offering a paid internship (1 – 3 months) working on our latest wildlife documentaries!
This is a great opportunity for young nature lovers to get involved, have input and get some great experience in a very niche industry.
Please note if you are studying and cannot commit to full time but would like to be involved we could potentially hire you as a part term intern. This is a unique opportunity to join a small team following Singapore’s wildlife.
The ideal candidate will want to gain experience in working in the field – duties will include:
- helping to track wild animals,
- assist with carrying equipment,
- assist with planning of shoots
- potential camera experience depending on skill levels,
- some office duties such as research and planning.
There are potential of night shoots, over night camping shoots, early starts. You will likely be seeing parts of Singapore that most people don’t!
This is a role where hard work and enthusiasm will be rewarded with increased opportunities and responsibilities and you will really get a chance to be part of the team.
You don’t necessarily need any prior experience but preference will be given to people with a experience/enthusiasm for wildlife and TV documentary.
Must be based in Singapore. Start date immediately.
Please contact the Production Manager at firstname.lastname@example.org with a CV and cover letter.
The biology, life history and phylogeny of Osedax, deep-sea siboglinid polychaetes (boneworms, bone-eating or zombie worms) which bore into bones of whale carcasses to feed on lipids.
Department of Biological Sciences
National University of Singapore
“Ecology, genetics and conservation of pangolins”
Graduate Student, NUS Biological Sciences
Wed 05 Aug 2015: 2.00pm
@ Conference Room-II (S1 Level 3, mezzanine)
Supervisor: Assoc Prof Evans, Theodore Alfred
Mammal species in East and SE Asia are at the highest risk of extinction for mammals anywhere in the world. Of this select group, the ant and termite eating scaly pangolins (Family Pholidota) are particularly threatened. Pangolin populations are in severe decline in part due to habitat loss and deterioration; however, a greater threat is increasing hunting. Pangolins are hunted for the illegal international trade of pangolin skins and scales for traditional medicine, and their meat constitutes a high-status delicacy in many regions. While pangolins are protected by international and local laws, these have been poorly enforced and are thus largely ineffective for conservation. Sadly, pangolins are now the most heavily trafficked animal in illegal wildlife trade globally.
Illegal wildlife trade networks are poorly understood, and the origin of seized pangolins and pangolin products is difficult to determine due to the large range sizes of most pangolin species. Conservation action and management plans are urgently required for all pangolin species. Unfortunately, little is known about their basic biology, ecology and threats, which is essential to formulate such plans.
My doctoral research project aims to collect data necessary to strengthen the evidence-base for informing robust conservation action and management plans for Asian pangolins. Specifically, I aim to (1) investigate status and threats of Chinese pangolin (Manis pentadactyla) in Hainan, South China, using local ecological knowledge (2) investigate genetic population structure of Sunda pangolin (Manis javanica), and compare DNA of accurately georeferenced pangolin specimens with samples seized from illegal wildlife trade of unknown origin, in order to test and enhance forensic genetic techniques for pangolins, (3) investigate dispersal movement, home range and habitat selection of Sunda pangolin in Singapore, and (4) work with varied local and international stakeholders, such as the Singapore Pangolin Working Group, to reflectively evaluate conservation projects for Sunda pangolin.
Neo Mei Lin says,
“I am honoured to be nominated by The Singapore Women’s Weekly for this award, and had a chance to see what’s like behind the scenes of fashion, makeup and glam. I couldn’t ask for more as I already feel like a winner!
I hope my interview reaches out to a different audience, and for them to see what’s like to be a marine biologist and environmentalist.”
Courtesy of The Singapore Women’s Weekly, August 2015.
In a similar vein, see: