The Necessity for Studies on Biodiversity

The world’s biodiversity is not distributed uniformly throughout the globe. Some areas such as the tropical rainforests, seas and coral reefs teem with the varieties of life whereas others such as some deserts and polar regions are almost devoid of them (Gaston, 2000). The countries of Southeast Asia with their tropical jungles and seas, are rich with biodiversity. However, with the rapid pace of development globally, every day species are becoming extinct sometimes without us even knowing that they had ever existed. Even in a developed country such as the USA, one third of her plant and animal species are at risk of extinction (McCann, 2000). Hence, taxonomic and biosystematic studies of Southeast Asian plants, animals and microbes should be priority areas. So should studies on their genetics, reproductive biology, life cycles, physiology, feeding habits, migration patterns, predators and their sensitivities to environmental changes.

Biodiversity is much more than counting species and different measures of it can elucidate ecological and evolutionary processes that have resulted in the present state of biodiversity (Purvis and Hector 2000). Unique habitats such as the Straits of Malacca, mangrove swamps, seagrass beds, caves, highlands and coral reefs should be given emphasis. Conservation efforts and studies on rare and endangered species for example arowana, marine turtle, terrapin, dugong, orang utan, tiger, mouse deer, rafflesia, wild vigna and pitcher plants should be continued and better funded. Some of these species are already of economic significance or can be developed for commercial uses provided they are no longer endangered species through our research efforts. Another issue to consider is the impact of introduced species such as Acacia mangium trees and the freshwater crayfish Cherax quadricarinatus from Australia on the Southeast Asian ecosystem, flora and fauna.

RETROSPECT

Southeast Asia is one of the success stories as far as the application of biology especially genetics to agricultural production is concerned for rubber and oil palm mainly through the efforts of scientists working in our world renown rubber and oil palm research institutes such as Ong, Rajanaidu, and Cheah (Ong et al., 1981, Rajanaidu et al., 1983, Singh et al., 2008.). We are the world’s leading producers of these two essential commodities although they were crops introduced here in the late 19th and early 20th centuries from South America and Africa, respectively. However, the picture is not so rosy for our own indigenous flora and fauna and nowhere is this more clearly illustrated than in our food production despite the fact that the excellent International Rice Research Institute is located in the Phillipines. For example, local genetic diversity information is not available for the ten major types of marine fishes landed in Malaysia (Tan, 1998). However, the situation is a bit brighter when it comes to freshwater aquacultured fishes such as the river catfish, Mystus nemurus, and tilapia (an introduced African fish) and marine and freshwater prawns and the green-lipped mussel, Perna viridis, which has potential for use as a bioindicator of pollution (Usmani et al 2003, Yap et al 2002, 2003.). Morphology usually cannot distinguish between populations and stocks within species or even between closely related species. Choices of stocks to be used in crosses should ideally be made with the knowledge of genetic distances calculated from gene frequency data of molecular loci since stocks differ to varying degrees and are not all equally suitable for breeding programmes (Ferguson, 1994) while their heterozygosity levels should be maintained to prevent the deleterious effects of inbreeding (Guo, 2000).

PROSPECT

What has been discussed about the importance of conservation, maintenance and utilization of genetic diversity in aquacultured breeding stocks is equally applicable for other agriculturally important organisms such as our numerous and delicious fruiting plants and fragmented or small populations of wild plants, animals and microbes. Another point of concern is the real danger of the loss of traditional breeds of plants and animals in Southeast Asia either through over exploitation such as for medicinal plants like Eurycoma longifolia (tongkat ali) or through neglect for example local rice varieties and livestock breeds such as the indigenous goat (Barker et al 2001), swamp buffalo (Barker et al 1997a, 1997b, Lau et al 1998), Kedah-Kelantan cattle (Kasim et al 1981) and village chicken. Even the progenitor of all the chicken breeds in the world, the jungle fowl is indigenous to Southeast Asia. This is of global concern (Hodges, 1992) since farmers everywhere, usually with government support, are switching towards imported high yielding varieties of plants and animals which often need large inputs of high quality fertilizers, water, pesticides and feed before they can yield at their maximum potential. Unless these requirements can be readily met continuously, their yields are often disappointing. When the need for the locally adapted traditional plant and animal varieties is finally realized it may be too late as they may have vanished during the time when the imported varieties and breeds are being extensively used.

The identification, isolation and characterization of unique chemical compounds from the region’s rich biodiversity such as our oil, tannin and phenolic compound rich indigenous tropical plants, animals such as sea cucumbers and microbes need to be done. Not only are such compounds useful in biosystematics (Adams, 2000) but they may also be useful as medicines for example quinine and as insecticides for example pyrethroids or as biological control agents such as Trichoderma spp (Chakraborty and Chatterjee, 2008). Compounds that are of potential medical importance will have to be subjected to the usual animal and clinical tests which are expensive and time consuming undertakings. The biochemical pathways for the synthesis and metabolism of potentially useful compounds should also be investigated as should defense mechanisms, symbiotic relationships and metabolic and biochemical pathways unique to tropical organisms and environments. Hence, pharmaceuticals and nutriceuticals could be priority areas for research. Moreover, exact species identification is essential as one member of a cryptic species complex (species that look alike morphologically but are genetically distinct) may yield a medicine that can cure us but another member of the same species complex may contain a product that can kill us. The existence of cryptic species complexes is fairly common in Southeast Asian organisms (Latiff et al., 2008).

CONCLUSION

It is often the case that every significant break through in agriculture was preceded by the discovery of some basic biological information. For example, the current widespread practice of planting the tenera type of oil palm in commercial plantations which significantly raised palm oil production was preceded by the discovery of the gene controlling the oil palm fruit shell thickness by Beirnaert and Vanderweyen in 1941 during the course of their research work in tropical Africa (Corley and Tinker, 2003.). Hence, fundamental biological research is important and needs to continue to be supported with adequate and meaningful funding so that our rich biological resources can be well characterized and understood. This will enable them to be utilized economically for the benefit of humankind at their optimal sustainable levels that allow them to continue to thrive in our unique species rich tropical ecosystem. In this regard it is gratifying to note that in the effort to utilize the much touted marker assisted selection (MAS) approach to improve the production of our economic plants and animals, funding had been made available to develop molecular markers for species like oil palm (Singh et al., 2008), Asian river catfish, Mystus nemurus, (Usmani et al., 2003) and the Asian giant freshwater prawn, Macrobrachium rosenbergii, (Bhassu et al., 2008) so that high density genetic maps can be generated for them. Such a map is essential before the MAS approach can be effectively applied in the breeding program of any one species (Liu and Cordes, 2004). Therefore, to enable us to be good trustees of the treasure trove of natural resources that our region has been richly endowed with, it is strongly recommended that intensive studies on the diversity of Southeast Asia’s rich and diverse biological resources be conducted so that they may be rationally managed, conserved and wisely utilized for the benefit of humankind.

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