Looking up at the night sky, we can see millions of galaxies suspended in our universe. This has mesmerised generations upon generations of people. Looking down, we can also see a galaxy of our own: our oceans. Millions of saltwater organisms are sustaining the marine ecosystems, and with the advancement of technology used in studying the marine life, many more will be discovered. In 2005, a study by marine biologist Kent Carpenter (1) showed that the hotspot of marine biodiversity is in the Indo-Malay-Philippines Archipelago (IMPA), particularly in a region now called as the Coral Triangle (CT). A number of studies conducted on the Coral Triangle, the world’s most diverse marine ecosystem, discusses its formation, identification, and conservation.
While the CT is known as the marine biodiversity hotspot of the world, little is known about its origins (1). Since the CT lies in the tropics, the common paradigm that exists when talking about its origins is that it is a ‘cradle’ of new organisms (2). New species originate from tropical areas, such as the CT, and these species will spread out and populate farther regions. However, in a study by Chou et. al., it was found that the rate of endemism in the CT is low and this implies that the species present in the CT are widespread species which originated from other regions. Factors such as the geographical process that the CT had undergone and the diversity of the neighbouring regions should also be looked into.
Studies conducted in the CT during the early 2000s showed that multiple data sets share a common trend: the marine biodiversity in the IMPA is the highest on a global scale (3). Though the IMPA is well known for widespread variation of species that can be found in the region, studies in IMPA highlights the number of coral reefs present in the region for most of marine organisms are dependent on the presence of coral reefs (4), thus its name Coral Triangle. Invertebrate and vertebrate surveys are also at its peak, but most studies are particular on reef and shelf density along longitudinal and latitudinal gradients (5).
The Coral Triangle is one of the world’s greatest marine resource. Coastal communities along its shores are highly dependent on the Coral Triangle for their livelihood. In a study led by Swansea University, the results showed that seagrass meadows in Indonesia are widely damaged and will cause a decline in the fishing livelihood of the locals (6). Aside from the communities, the tropical reef biodiversity is at risk of being lost due to threats from human activity and coral bleaching (7). To address this, continuous efforts on ecosystem management are being developed on different regions along the Marine Protected Areas (MPAs) (8).
To conclude, the Coral Triangle has been identified as the world’s most diverse marine biodiversity by several studies conducted to survey the density of its reefs. Its origins are still being debated as more studies emerge, shedding light into the role of geographical evidences in the widespread distribution of species from nearby regions to the CT. The marine resources from the CT are at stake; thus, ecosystem management efforts are being put forward in order to preserve the Coral Triangle.
1: Huang, D., Goldberg, E. E., Chou, L. M., & Roy, K. (2018). The origin and evolution of coral species richness in a marine biodiversity hotspot. Evolution, 72(2), 288-302.
3: Carpenter, K. E., & Springer, V. G. (2005). The center of the center of marine shore fish biodiversity: the Philippine Islands. Environmental biology of fishes, 72(4), 467-480.
4: Hoeksema, B. W. (2007). Delineation of the Indo-Malayan centre of maximum marine biodiversity: the Coral Triangle. In Biogeography, time, and place: distributions, barriers, and islands (pp. 117-178). Springer, Dordrecht.
5: Förderer, M., Rödder, D., & Langer, M. R. (2018). Patterns of species richness and the center of diversity in modern Indo-Pacific larger foraminifera. Scientific reports, 8.
6: Richard K.F. Unsworth, Rohani Ambo-Rappe, Benjamin L. Jones, Yayu A. La Nafie, A. Irawan, Udhi E. Hernawan, Abigail M. Moore, Leanne C. Cullen-Unsworth. Indonesia’s globally significant seagrass meadows are under widespread threat. Science of The Total Environment, 2018; 634: 279 DOI: 10.1016/j.scitotenv.2018.03.315
7: Roberts, C. M., McClean, C. J., Veron, J. E., Hawkins, J. P., Allen, G. R., McAllister, D. E., … & Vynne, C. (2002). Marine biodiversity hotspots and conservation priorities for tropical reefs. Science, 295(5558), 1280-1284.
8: Weeks, Rebecca & M Aliño, Porfirio & Atkinson, Scott & Beldia Ii D E, Pacifico & Binson, Augustine & Campos, Wilfredo & Djohani, Rili & Green, Alison & Hamilton, R & Horigue, Vera & Jumin, Robecca & Kalim, Kay & Kasasiah, Ahsanal & Kereseka, Jimmy & Klein, Carissa & Laroya, Lynette & Magupin, Sikula & Masike, Barbara & Mohan, Candice & White, Alan. (2014). Developing Marine Protected Area Networks in the Coral Triangle: Good Practices for Expanding the Coral Triangle Marine Protected Area System. Coastal Management. 42. 183-205. 10.1080/08920753.2014.877768.