Click to read JC Mendoza’s Nat Geo Extreme Explorer article in which he tells some stories from his many encounters during expeditions and examinations of crustacea; well done JC!
We are playing catch-up on news about Seshadri, one of the PhD students in the Evolutionary Ecology and Conservation Lab who is back in Singapore after spending the summer in India doing field work.
Seshadri’s master’s research on the effects of selective logging on frogs in the Kalakad Mundanthurai Tiger Reserve was recently published in Biotropica and featured on the conservation website Mongabay.com. The reserve is part of the Western Ghats, which along with Sri Lanka is a biodiversity hotspot that is home to many threatened endemic amphibians. Seshadri found that negative impacts on densities and community composition of anurans persisted in logged forest even 40 years after moderate logging was ceased.
The degradation from logging has led to the loss of ecological niches – particularly affecting stream- and litter-dwelling species. It appears that anuran assemblages in the region do not recover quickly from habitat degradation due to logging.
Seshadri will continue to work on threatened amphibians in the Western Ghats for his PhD dissertation, focusing on the ecology and behaviour of bamboo nesting frogs. His research will be supported by the Mohamed bin Zayed Species Conservation Fund and Chicago Zoological Fund, which are competitive grants awarded to conservation efforts to save species worldwide.
CITATION LINK: K.S. Seshadri (2014). Effects of Historical Selective Logging on Anuran Communities in a Wet Evergreen Forest, South India. Biotropica 46:615-623.
Congratulations to Associate Professor Antónia Monteiro and colleagues on the publication of their latest paper, “Nymphalid eyespot serial homologues originate as a few individualized modules” in the Proceedings of The Royal Society B.
The paper was highlighted on ScienceDaily in “Butterfly ‘eyespots’ add detail to story of evolution“. The first author, Jeffrey Oliver, a postdoctoral scholar in the Department of Integrative Biology of the Oregon State University College of Science stated that the study indicated how continued mutations allowed eyeposts to move to different positions on the wings to perform a different function from its original placement. With the help of butterfly eyespots, we are inching closer to understand the existence of serial homologues and even the fundamentals of evolution.
For full citation: J. C. Oliver, J. M. Beaulieu, L. F. Gall, W. H. Piel, A. Monteiro. Nymphalid eyespot serial homologues originate as a few individualized modules. Proceedings of the Royal Society B: Biological Sciences, 2014; 281 (1787): 20133262 DOI: 10.1098/rspb.2013.3262
Veera is an NUS biology graduate from the late 80’s who setup Greenology in 2008. Lovely to see him featured in Singapore International Foundation’s Oct-Dec 2013 issue of Singapore.
“… he set up Greenology to spread the concept of urban ‘green walls.’ A green wall is found in nature where plants grow naturally on vertical surfaces. Using this concept, plants are introduced into compact living spaces — a vital point as more than half the world’s population now live in cities.
And this is a trend, the World Health Organisation says is going to continue, with seven out of every 10people living in cities by 2050.
Greenology’s big break came when it was commissioned to build a green wall for the Formula 1 Pit Building in 2010.Things were looking up for Veera and it appeared that the business had turned the corner.
However, towards the end of that year he contracted a rare medical condition, Parsonage-Turner syndrome.“It rendered both my arms unusable.They were paralysed, and for six months I couldn’t eat or drink. It also caused tremendous pain.” Because it is so rare,his doctors were uncertain about how it should be treated.”
Most people don’t think of frogs as being good parents, but in fact amphibians have a wide diversity of reproductive strategies, including guarding their eggs.
Sheila Poo, from the Evolutionary Ecology and Conservation Lab, just published her first paper entitled “The Adaptive Significance of Egg Attendance in a South-East Asian Tree Frog” in the journal Ethology. For the past three years, she has been closely observing the treefrog Chiromantis hansenae in Thailand to find out about its life history and the role of parental care in larval survival. Her study is the first to show that egg attendance by female C. hansenae plays a critical role in offspring survivorship.
Sheila is currently in the field again in Thailand, hard at work collecting even more data. Below is a short video with footage from her study site created by one of her field assistants, Adair McNear, giving a glimpse of what it is like working on these critters.
Congratulations Sheila, all the time you spent wading in ponds in the dark has paid off!
BEFORE dawn broke last Monday, Ms Neo Mei Lin and Ms Kareen Vicentuan set off on a yacht from Sentosa on a 45-minute journey.
Taking advantage of the low spring tide, they anchored just off Terumbu Pempang Tengah, a submerged reef near the southern islands, before piloting a rubber dinghy onto the reef flat.
Their mission? To search for a creature once abundant in Singapore but now rarely seen – the giant clam.
Ms Neo, 25, a PhD student, and Ms Vicentuan, 31, a research assistant, both from the National University of Singapore (NUS), are part of a small team of biologists that wants to repopulate Singapore’s coral reefs with hundreds of giant clams, organisms which contribute to the reefs’ complexity.
But to do this, the biologists need to spawn clams of local origin. To do that, they first need to find them.
This project is funded by the National Parks Board, and its principal investigator, Dr Peter Todd, said that the results are important for Singapore’s marine biodiversity.
‘From the evidence of our research, we are certain that giant clams were once abundant in Singapore,’ said Dr Todd, 45, an assistant professor in the NUS’ department of biological sciences.
Old records dating back to the mid- 1850s indicate that the waters around Singapore used to have five species of giant clam, he said. In the 1950s, the clams could still be easily seen from the shore.
‘We have lost a lot of reefs, where the clams live, due to land reclamation. Furthermore, the waters around Singapore have more sediment in them than they used to, which reduces light penetration,’ Dr Todd explained.
‘As the clams photosynthesise, they need light, so that may have contributed to their decline.’
Another problem of sedimentation on the reefs, he added, was that it could cover up solid substrate, which clam larvae need to attach themselves to as they develop.
Lastly, he noted that the harvesting of clams for food likely contributed to their decline.
When Ms Neo surveyed 87,500 sq m of Singapore’s coral reefs in 2009 and 2010, she found only 59 individual clams of two species.
‘The aim of the project is to put back what we lost,’ said Dr Todd.
Last Monday, using GPS coordinates from previous expeditions, the two researchers found one small specimen of Tridacna squamosa, otherwise known as the fluted giant clam for the leaf-like projections on its shell, but left it alone as it was too young to breed. After another 20 minutes, they found another fluted giant clam large enough to be brought back to the Tropical Marine Science Institute on St John’s Island. Marking it, they went to look for others.
In the 11/2 hours of remaining low tide, two Tridacna crocea, otherwise known as the burrowing giant clam, were found, and their locations recorded. But when the tide came in, the duo returned to the marked fluted giant clam.
Soon, they separated the giant clam from its base and put it into a container, ready to be transported to the lab.
There, giant clams, some local and some from overseas, will be induced to breed, their offspring raised, and experiments conducted to see how they can be transplanted onto Singapore’s reefs.
It will, however, be a long time before the team knows if the placement of giant clams has been successful. Said Ms Neo: ‘Realistically, it will take seven to 10 years to know if this will work.’
But as long as giant clams can grow once again on the reefs, the team will be happy. ‘The wait will definitely be worth it,’ she said.”
Li Daiqin’s paper with colleagues on genital amputation in the orb-web spider Nephilengys malabarensis has received considerable coverage, congratulations, Daiqin!
A large female Nephilengys malabarensis spider with the severed
copulatory organ (highlighted by the red square) of the smaller,
red-coloured male, embedded in her genitals.
Daiqin Li, J. Oh, S. Kralj-Fišer and M. Kuntner, 2012. Remote copulation: male adaptation to female cannibalism. Biology Letters, 01 Feb 2012; doi: 10.1098/rsbl.2011.1202.
“Sexual cannibalism by females and associated male behaviours may be driven by sexual conflict. One such male behaviour is the eunuch phenomenon in spiders, caused by total genital emasculation, which is a seemingly maladaptive behaviour. Here, we provide the first empirical testing of an adaptive hypothesis to explain this behaviour, the remote copulation, in a highly sexually cannibalistic orb-web spider Nephilengys malabarensis.
We demonstrate that sperm transfer continues from the severed male organ into female genitals after the male has been detached from copula. Remote copulation increases the total amount of sperm transferred, and thus probably enhances paternity. We conclude that the mechanism may have evolved in response to sexual cannibalism and female-controlled short copulation duration.”
And The Guardian used photos from Lee Qi Qi’s wikispaces page for the species.
The article has been covered by:
“Genital amputation, that is, genital damage or loss, seems maladaptive because it renders the amputee functionally sterile, but is nevertheless common in sexually dimorphic spiders. In these species, male genital amputation correlates with plugging of female genitals and with sexual cannibalism. Genital amputation in male spiders may be partial or full; the latter is known as the eunuch phenomenon. We tested two adaptive hypotheses about eunuch behaviour in an orb web spider, Nephilengys malabarensis: (1) the plugging hypothesis (i.e. broken male genitals (palps) effectively plug the female genitals) and (2) the better fighter hypothesis (i.e. eunuch males are better fighters than their intact rivals).
By staging mating trials, we documented genital amputation (occurrence and frequency), sexual cannibalism and genital organ reuse, morphologically examined plugs to infer their effectiveness, and conducted a series of maleemale contests to determine whether eunuch males were better fighters. Copulations always resulted in amputation of the palps: 87.5% of males became eunuchs directly during copulation and plugged females, while 12.5% of males first partially damaged the palps and then severed them after copulation. Sexual cannibalism and plugging effectiveness both reached 75%. Eunuchs guarded females, were highly aggressive and active, and initiated and won contests more often, whereas intact males and half-eunuchs showed significantly lower levels of guarding behaviour, aggression and general activity. Thus, both hypotheses are supported and we conclude that the eunuch phenomenon is adaptive.”