James Guest, until recently, was a Lee Kuan Yew post-doctoral research fellow with the Marine Lab. All this while he has been working to understand the extent of spatial and temporal variation in thermal tolerance of corals, as this information would be crucial to the design of marine protected areas against climate change.
He shares the good news that PLoS ONE has published a paper today (date in USA is 09 Mar 2012) which he submitted about adaptation by corals in mass coral bleaching sites in Singapore and Malaysia.
As he says, “the research provides solid field evidence that certain coral taxa in Singapore and Malaysia have the capacity to adapt/acclimatise to thermal stress.”
The image from the paper below shows the different bleaching responses from their three study locations in Sumatra, Malaysia and Singapore. The photos indicate a reversed response of Acropora in Singapore and Malaysia.
James told me enthusiastically he hopes these stunning images “provides a bit of hopeful news among the general climate change doom and gloom!”
Contrasting coral bleaching patterns during 2010. Bleached Acropora colonies from (A) Pulau Weh, north Sumatra, Indonesia where patterns in bleaching susceptibility were normal. Reversals in bleaching susceptibility gradients in (B) Singapore and (C) Tioman Island, Malaysia, where healthy Acropora colonies were found adjacent to bleached encrusting, foliose and massive colonies: corals which are usually relatively resistant to bleaching.
Download the paper here; citation: Guest JR , Baird AH , Maynard JA , Muttaqin E , Edwards AJ , et al. (2012) Contrasting Patterns of Coral Bleaching Susceptibility in 2010 Suggest an Adaptive Response to Thermal Stress. PLoS ONE 7(3): e33353. doi:10.1371/journal.pone.0033353
Abstract
Background: Coral bleaching events vary in severity, however, to date, the hierarchy of susceptibility to bleaching among coral taxa has been consistent over a broad geographic range and among bleaching episodes. Here we examine the extent of spatial and temporal variation in thermal tolerance among scleractinian coral taxa and between locations during the 2010 thermally induced, large-scale bleaching event in South East Asia.
Methods/Principal Findings: Surveys to estimate the bleaching and mortality indices of coral genera were carried out at three locations with contrasting thermal and bleaching histories. Despite the magnitude of thermal stress being similar among locations in 2010, there was a remarkable contrast in the patterns of bleaching susceptibility. Comparisons of bleaching susceptibility within coral taxa and among locations revealed no significant differences between locations with similar thermal histories, but significant differences between locations with contrasting thermal histories (Friedman = 34.97; p 0.001).
Bleaching was much less severe at locations that bleached during 1998, that had greater historical temperature variability and lower rates of warming. Remarkably, Acropora and Pocillopora, taxa that are typically highly susceptible, although among the most susceptible in Pulau Weh (Sumatra, Indonesia) where respectively, 94% and 87% of colonies died, were among the least susceptible in Singapore, where only 5% and 12% of colonies died.
Conclusions/Significance: The pattern of susceptibility among coral genera documented here is unprecedented. A parsimonious explanation for these results is that coral populations that bleached during the last major warming event in 1998 have adapted and/or acclimatised to thermal stress. These data also lend support to the hypothesis that corals in regions subject to more variable temperature regimes are more resistant to thermal stress than those in less variable environments.
James is now a research fellow at University of New South Wales (UNSW Sydney) working with Prof. Peter Steinberg’s group in the Centre for Marine Bio-innovation (CMB), who is co-director of the marine ecology group within NTU’s Advanced Environmental Biotechnology Centre (AEBC), where James is now a visiting research fellow. James helps run a multi-disciplinary group of scientists, including geneticists, microbiologists, chemists and ecologists to tackle problems facing tropical marine ecosystems in Singapore and the region. You can email him at jrguest@gmail.com
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When not lurking the corridors of the department, Nalini Puniamoorthy is a doctoral candidate at the Institute of Evolutionary Biology and Environmental Studies at University of Zurich.
