RESEARCH COMMUNICATIONS
Development of a Biogeographical Information System for conservation monitoring of biodiversity V. N. Neelakandan*, C. N. Mohanan and B. Sukumar Centre for Earth Science Studies, P.B. No. 7250, Akkulam, Thiruvananthapuram 695 031, India
The need to document and conserve biodiversity has become a necessity in the wake of increased threats from deforestation, alteration in land use, soil degradation, pollution and climatic change. Developing technologies with more predictive capabilities could help the society address some of the concerns affecting nature and biodiversity. Current electronic inventories provide limited information on biodiversity, its environmental status, bioclimate, evolutionary history and management units of conservation. This communication explains a system that provides species-specific and site-specific information with improved data semantics to help conservation monitoring, eco-restoration and sustainable use of biological resources. Keywords: Biodiversity, Biogeographical Information System, conservation monitoring, eco-restoration. ONE of the major tasks proposed in the global initiative for biodiversity conservation is to document floral, faunal and microbial diversity with detailed accounts of species of all regions and developing an integrated interactive information system1–4. Many herbaria and museums in the developed countries have started using Information Technology (IT) tools and techniques to create electronic repositories on specific groups of species or species of a region5–8. Most of these inventories provide only limited details regarding species habitat and environment. This is a serious limitation in view of the importance of geomorphological and ecological factors in assessing and understanding the distribution of species and ecosystem status9–15. Developing electronic inventories of specified groups of species based on catalogued specimens in a herbarium and museum has recently caught the attention of researchers in India8,16–22. Many of these inventories do not provide geographical and environmental details of taxa. Developments in the field of Geographic Information System (GIS) and Remote Sensing (RS) have opened new avenues to map and analyse distribution of biological resources and also to monitor them19–29. Most of the recent developments reported are based on landscape-level approach using satellite images and/or smaller scale vegetation maps to analyse land use/ cover changes. In certain cases, different thematic maps are also used in the preparation of atlas of endemic trees19 as well as in eco-distribution mapping of medicinal plants20. *For correspondence. (e-mail:
[email protected]) 444
These landscape-level approaches deal mainly with a small group of plants or organisms and a few environmental parameters on maps of smaller spatial scale. Retrieving information on complete biodiversity status along with all environmental details from such systems is difficult. GIS-based approaches can be effectively used for capturing spatial and environmental details on biodiversity to overcome some of the above limitations. The Biogeographical Information System (BGIS) developed by the authors provides detailed information on bioresources and their environment. The approach employed is to map independently the environmental attributes of a biological species and its spatial distribution over space and time and then integrate them with community data. Work carried out for Kollam and Pathanamthitta districts and parts of Idukki district in the southern Western Ghats region highlights the applications of BGIS30–32. The area (~5900 km2) covers Periyar Tiger Reserve (PTR) in the north and Shendurney Wildlife Sanctuary (SWS) in the south, which is part of the southern Western Ghats of peninsular India – a global hotspot of biodiversity33–36. Here new species are being discovered and even lost before being described. Old information on biodiversity from the region exists as natural history collections. There is also literature on species scattered in different books, journals and other publications from within and outside the country. Data obtained from herbarium and museum collections, literature and field surveys are invariably collated for the bioresources database37–40 (C. N. Mohanan, unpublished). Converting these datasets into electronic format provided easy access to valuable biodiversity baseline information. Apart from documenting, identification tools are developed for groups of biota in order to further facilitate local or regional ecological studies, conservation efforts and bioprospecting. Thematic maps on geographical and environmental parameters in BGIS are prepared based on Survey of India (SOI) topographic sheets (1 : 50,000 scale), maps and/or data from Forest Department, State Soil Survey Department, Geological Survey of India, Forest Survey of India, India Meteorological Department and other sources. The themes used include altitude/contour, water bodies and drainage, basin boundaries, geology, soil type, soil texture, rainfall, temperature, potential evapotranspiration (PET) and number of rainy days. Administrative boundaries like district, taluk, block, panchayat, as well as forest division and range are added. Current land use/cover, vegetation and Normalized Difference Vegetation Index maps derived from satellite imagery are also incorporated. The spatial database thus developed has more than 20 layers of digital map themes integrated in MapInfo GIS core with resolution varying from 50 m × 50 m to 500 m × 500 m depending on the source of the themes. The bioresources database consists of five relational tables, viz. Taxonmaster, Family, Species, Locality and Climate. Taxonmaster records store data on species occurrence with scientific name, location, altitude, landform, soil and longitude and latitude for geoCURRENT SCIENCE, VOL. 90, NO. 3, 10 FEBRUARY 2006
RESEARCH COMMUNICATIONS Scanned maps and processed satellite images
Data on flora, fauna and microbes
GIS attribute tables GIS Map database (spatial data) RDBMS database on bioresources
GIS link
BGIS customi -zation module
Query processing, analysis and display of maps and bioresource data in GIS core
Windows NT workstation Figure 1.
Block schematic of BGIS.
coding. Family table stores taxonomical details, while species records contain data on scientific name, synonyms, common name, status, habit, habitat, importance/use, literature, sketch/photograph and audio/video. Locality table stores descriptive data on ecosystem, river basin, administrative and forest boundaries, land use, geology and location. Climate table contains data on vegetation, climate type, rainfall, temperature and humidity. Integration of bioresources database with spatial database in BGIS enhances biodiversity data semantics. It is possible to assess current status and threats to habitat of each taxon, its distribution and key environmental factors at work using BGIS. Detailed inventory of multi-taxa provides a relatively complete and broader understanding of site-specific and region-specific mode of biodiversity distribution status. The database can be upgraded as and when new additions/ species are discovered and trends reported. BGIS is customized by invoking MapInfo interface through MapBasic program codes and adding custom menus, submenus, dialogue boxes and tool boxes41. A simplified block schematic of the BGIS is shown Figure 1. Figure 2 shows screenshots of customized BGIS with digital map layers and bioresources data in tabular form as well as user-interface for query processing and information retrieval. Spatial and attribute queries on species and environment as well as report generation are also possible with BGIS. The BGIS comprises of spatial and bioresources (4524 species) data representing a cross-section of the State from the coastal plains to the high-altitude forest regions of the Western Ghats. Physiographically, the area can be divided into lowland, midland and highland. Geologically, it is an Archaean terrain. Recent sediments occupy lowlands bordering the 45-km long coastline. Soils of the highland region are mainly forest loam, while lateritic soil predominates the midlands. These laterites have isolated patches of brown hydromorphic soil at the interfluvial areas. Riverine alluvium occupies the river valleys. The lowland in the west is occupied by greyish Onattukara soil, which is bordered along the seacoast by coastal alluvium. Periyar, Pamba, Manimala, Achenkovil, Kallada, Ithikkara and CURRENT SCIENCE, VOL. 90, NO. 3, 10 FEBRUARY 2006
Pallikara are the seven major rivers in the region, which are west-flowing and perennial. Major reservoirs are Periyar, Pamba and Kakki, while the largest freshwater body is at Sasthamcotta. Ashtamudi lake is the major backwater in this region. The area enjoys a tropical humid climate. Mean annual temperature varies from 21.5°C in the east to 27.5°C in the west. The mean annual rainfall varies from 4000 mm in the Western Ghats to 2000 mm in the plains. Most of the midland and highland regions gets moderate to high rainfall. Vegetation comprises of tropical evergreen, semi-evergreen, moist deciduous, subtropical montane and montane temperate forests. About 6077 plant occurrences belonging to 3311 species in the database have been used for spatial analysis. They belong to 181 families and 1114 genera. This is against 4575 species of flowering plants reported from the whole state42, which means that about 72% of the state flora is present in 15% of the land area. Many of the plants are distributed in wet and damp areas. About 491 plants have medicinal properties. There are 1088 rare, endangered, and threatened (RET) plant species among the flora, with 1958 occurrences. Similarly, 2113 animal occurrences belonging to 1213 animal species in the database have been considered for analysis. Among these, 482 are birds, 277 reptiles, 194 amphibians, 125 fishes and 135 mammals. Little information is available on invertebrates and lower groups of plants. In the absence of detailed data, methods involving estimation, inference and projection on the status of taxa are based on currently available data and their extrapolation. It may be noted that the results are based on limited data, and field check and inferences are likely to change when new information on lower group of organisms is added. Distribution of species in the region with respect to spatial and environmental variable has been analysed. Details of animals and plants in different landforms from coastal plain to high mountain are given in Table 1. More than half of the total area is covered by denudational hills, high mountains and structural hills. Plant occurrences in high mountains, structural hills and high plateau as well as animal 445
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Figure 2. Screenshot of customized BGIS (top left) user interface for displaying map layers, species search, environmental search, species information and output for taxonomy, environmental aspects, importance, picture and report of a plant (Rauvolfia serpentina).
occurrences in denudational hills and high mountains are relatively high. Maximum land area and high animal occur446
rences are associated with denudational hills in the midlands due to concentration of birds and amphibians. Low CURRENT SCIENCE, VOL. 90, NO. 3, 10 FEBRUARY 2006
RESEARCH COMMUNICATIONS Table 1. Landform Coastal plains Denudational hills Highly dissected hills Dissected erosional plains Structural hills High plateau High mountain
Animals
Plants
293 594 50 57 276 308 535
386 279 14 529 1766 1237 1866
RET plants Amphibians 39 73 3 140 605 310 788
Table 2. River basin Ayirur Ithikkara Pallikara Kallada Achenkovil Pamba Manimala (part) Periyar (part)
Figure 3.
Species distribution across landforms
21 170 4 9 22 54 61
Reptiles
Fishes
Mammals
Birds
Area (km2)
44 109 15 26 123 101 163
32 31 7 – 9 26 132
42 35 8 6 58 52 87
154 249 16 16 64 75 92
479.533 1570.88 694.666 270.379 1131.65 631.838 1135.18
Species distribution across river basins
Animals
Plants
RET plants
Amphibians
Reptiles
Fishes
Mammals
Birds
Area (km2)
7 56 269 693 179 353 10 546
3 49 382 1649 343 1279 13 2359
– 15 39 536 88 460 5 815
1 12 21 135 56 25 2 89
1 15 38 182 61 133 3 148
– 13 20 21 10 59 4 110
– 2 36 78 21 63 – 88
5 14 154 277 31 73 1 111
30.88 624.6 517.9 1313 890.2 1548 294.9 642.9
Altitudinal distribution of species.
count of species, both plants and animals, in the highly dissected hills of the midland region is mainly due to anthropogenic factors like settlement and cultivation. Species data for river basins (Table 2) indicate low occurrences of animals and plants in Ayirur, part of Manimala, Ithikkara and Achenkovil, while parts of Periyar, Kallada and Pamba show high concentration probably because of the large forest cover. Achenkovil and Ithikkara basins show less species count possibly due to large human settlement. The species distribution versus altitude plot in Figure 3 indicates concentration of plants in the elevation range of 100 to 500 m. Species distribution is also analysed with respect to bioclimatic zones and grids. The bioclimatic map is derived based on factors such as PET, rainfall, number of rainy days, temperature and forest/non-forest areas with 44 bioclimatic regions. Among these, 14 bioclimatic zones are identiCURRENT SCIENCE, VOL. 90, NO. 3, 10 FEBRUARY 2006
fied by considering three main factors, viz. forest/non-forest areas, PET and rainfall. It is known that bioclimatic factors considerably influence biodiversity pattern of the region and help to analyse distribution of species based on one or a combination of climatic factors. Grid-wise analysis provides better spatial concept of species distribution. A smaller grid size would be ideal for hilly terrain where geodiversity resulting from topography is more evident. Therefore 15′ × 15′ (~760 km2) grids, generated by the system, which divide the area into 12 parts are used here. Bioclimatic zones along with grids are shown in Figure 4. For biodiversity assessment the species diversity is assumed as a rough proxy of biodiversity. The species diversity in different grids and bioclimatic zones is then calculated and compared. On a global scale, areas with 1500 plants per 10,000 km2 (i.e. 0.15) are considered to be highly biologically rich, while those with less than 200 plants per 10,000 km2 (i.e. 0.02) are biologically poor43. Although this is in the context of plants, it is generally known that plant and animal diversities are correlated. Here average values of species per unit area for plants, RET plants and animals are found to be 1.03, 0.33 and 0.36 respectively. Based on the above criterion the entire area can be considered biologically rich, despite the fact that there are degraded patches. Details of species in different bioclimatic zones are given in Table 3. Bioclimatic zones I to X are in forest areas where altitude is above 100 m, while zones XI to XIV are in non-forest areas with altitude less than 100 m. The number of animals in zones II, IV and X and the number of plants and RET plants in zones II, III and V is relatively high, whereas birds, reptiles, amphibians and mammals are more in bioclimatic zone IV. Species per unit area for 447
RESEARCH COMMUNICATIONS Table 3. Item/zone Area (km2) Plants RET plant Animals Amphibians Mammals Birds Reptiles Fishes Plants/area RET plants/area Animals/area
Species distribution across bioclimatic zones
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
20.7 280 152 30 7 7 2 14 – 13.5 7.34 1.44
244 808 270 335 71 63 57 108 36 3.3 1.1 1.37
247.7 1439 435 117 – 7 35 1 74 5.8 1.57 0.47
650 469 136 547 117 62 230 133 5 0.72 0.21 0.84
644.5 1356 468 187 22 27 54 69 15 2.1 0.73 0.29
363 375 119 168 16 33 26 73 20 1.03 0.33 0.46
525 187 44 40 7 1 8 20 4 0.36 0.08 0.07
655 510 220 157 8 29 42 57 21 0.86 0.33 0.24
32.7 14 8 – – – – – – 0.78 0.24 0
999 415 42 343 29 42 174 55 43 0.42 0.04 0.34
41.9 1 – – – – – – – 0.02 0 0
Table 4. Item/grid Land area (km2) Plants RET plants Animals Amphibians Mammals Birds Reptiles Fishes Plants/area RET plants/area Animals/area
XIII
XIV
872.8 449.6 172 25 51 8 143 35 60 3 13 3 24 8 36 14 10 7 0.2 0.05 0.06 0.02 0.16 0.07
160 26 5 11 1 1 6 1 2 0.16 0.03 0.06
Species distribution across grids
1
2
3
4
5
6
7
8
9
10
11
12
434.9 23 7 17 2 – 4 5 6 0.05 0.02 0.04
540.9 41 11 77 6 13 19 21 21 0.08 0.02 0.14
443.5 377 34 298 22 35 160 42 37 0.85 0.08 0.67
597.9 732 266 148 51 19 32 36 10 1.22 0.44 0.25
760 242 58 468 114 11 225 92 3 0.32 0.08 0.62
589 35 12 24 10 2 2 10 1 0.06 0.02 0.04
166.5 1137 297 135 – 8 32 1 94 6.83 1.78 0.81
754.5 650 245 302 30 50 58 117 53 0.86 0.32 0.40
679.6 235 64 123 10 22 25 61 7 0.35 0.09 0.18
521.3 1499 505 180 20 59 48 75 1 2.88 0.97 0.35
129 512 263 331 78 69 56 122 7 3.97 2.03 2.57
256 595 207 16 – – 7 – 9 2.33 0.81 0.06
Figure 4. Map showing study area with bioclimatic zones and 15′ × 15′ grids. 448
XII
plants and RET plants in zones I–III, V and VI and animals in zones I–IV, VI and X is more than the average values for the region. This indicates the importance of conservation of PTR, SWS and adjacent areas (Figure 4). Similarly, Table 4 shows details of species falling in different grids. Species per unit area is found by dividing the number of species by actual land area. Species per unit area of plants and RET plants in grids 4, 7, 10, 11 and 12 forming part of PTR and adjacent Ranni forest division and SWS is more than the average values for the region, whereas animals per unit area in grids 3, 5, 7, 8, 10 and 11 is more than the average value. Concentration of plants, RET plants and animals in grids 11, 7 and 10 shows the importance of conservation as these grids corresponds to PTR and SWS, which are known to be biologically rich. The spatial distribution of RET plants against major landforms, geology, river basins and bioclimatic zones is shown in Figure 5 a and b. There is good correlation between occurrence of RET species and geological structure43. The linear drainage pattern of Kallada, Achenkovil and Pamba rivers clearly indicates structural control over landforms, especially strike valleys. The flow of groundwater and surface water through these fractures, joints and faults in CURRENT SCIENCE, VOL. 90, NO. 3, 10 FEBRUARY 2006
RESEARCH COMMUNICATIONS the hard rock region enriches soil moisture. This might have facilitated existence of evergreen forests and survival of maximum RET species. A break in the pattern of distribution of RET species is due to anthropogenic factors. An analysis of the ten most critically endangered plant species showed a similar trend in their distribution31. For example, the past distribution and area of occupancy44 of the critically endangered plant Sageraea grandiflora is shown in Figure 5 c. It had an area of occupancy 996 km2 from Peermade hills in the north to Ranni, Konni and Aryankavu forests towards the south along structural and denudational hills that are subjected to human settlement
a
b
and cultivation. Now it is seen only in restricted localities of SWS and is highly threatened and faces extinction. Its present area of occupancy is about 63 km2, which can be found by counting the number of smaller grids (area 21 km2) that make the convex polygon whose vertices are the sites of occurrence. There are several such species facing threat and extinction as evidenced from our studies31. The BGIS is found to be useful for biodiversity documentation and analysis. It is a powerful tool for the preparation of species database, atlases, derivative maps for identification of biological hotspots and preparation of habitat-wise conservation plans and for implementing national biodiversity strategies and action plans45. The BGIS provides on-the-spot information about the entire biodiversity of a region, distribution of a particular biological species at fingertips, identifies key environmental factors and hotspots, documents each species occurrences, and maps the habitat or spatial elements for conservation. It is also helpful to find out species on the verge of extinction and identify possible threats to their habitats, and to explore the existence of RET species in hitherto unnoticed habitats with similar ecological amplitude. It would also help in environmental impact analysis, estimate species loss when implementing developmental projects, construction of reservoirs and roads as well as to suggest/find alternatives. Since the BGIS integrates spatio-temporal inputs on land, water and climate, it could also be useful for evolving suitable management strategies for sustainable development of a region. Information related to biotechnology and traditional knowledge of the species can also be easily incorporated in the BGIS. It is felt that developing a full-fledged BGIS for every State in the country is required for preserving the rich bio-heritage. 1. 2. 3. 4. 5. 6. 7.
c 8. 9. 10. 11. 12. 13. 14. 15. 16. Figure 5. Distribution of RET plants against (a) major landforms and geology and (b) river basins and bioclimatic zones. (c) Distribution and area of occupancy of critically endangered plant Sageraea grandiflora across landform and bioclimatic zones. CURRENT SCIENCE, VOL. 90, NO. 3, 10 FEBRUARY 2006
17. 18.
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RESEARCH COMMUNICATIONS 19. Ramesh, B. R. and Pascal, J. P., Atlas of Endemics of the Western Ghats, India, French Institute, Pondicherry, 1997. 20. Ved, D. K., Barve, V., Noorunnisa Begum and Latha, R., Curr. Sci., 1998, 75, 205–208. 21. Ganeshaiah, K. N., Kathuria, S. and Uma Shaanker, R., Curr. Sci., 2002, 83, 810–813. 22. Ganeshaiah, K. N., Sasya Sahyadri, Univ. Agric. Sci., Bangalore, CD-ROM, 2003. 23. Shaily Menon and Bawa, K. S., Curr. Sci., 1997, 73, 134–145. 24. Narendra Prasad, S., Curr. Sci., 1998, 75, 228–235. 25. Nagendra, H. and Gadgil, M., Curr. Sci., 1998, 75, 264–271. 26. Ganeshaiah, K. N. and Uma Shaanker, R., Curr. Sci., 1998, 75, 292–298. 27. Ramesh, B. R., Menon, S. and Bawa, K. S., Ambio, 26, 529–536. 28. Nagendra, H. and Gadgil, M., J. Appl. Ecol., 1999, 36, 388–397. 29. Shi, H and Singh, A., J. Indian Soc. Remote Sensing, 2002, 30, 105–112. 30. Neelakandan, V. N., Mohanan, C. N. and Sukumar, B., A BioGeographical Information System. Indian Cartogra., 2001, 21. 31. Neelakandan, V. N., Mohanan, C. N., Sukumar, B. and Baijulal, B., Role of geoinformatics in biodiversity studies. Proc. National Symposium on Resource Management with Special Reference to Geoinformatics and Decentralised Planning, Trivandrum, 9–12 Dec. 2003. 32. Neelakandan, V. N., Mohanan, C. N. and Sukumar, B., Development of a Biogeographical Information System for Kerala. Project Completion Report submitted to the State Council for Science, Technology and Environment, Govt of Kerala, 2004. 33. Myers, N., Mittermeier, R. A., Mittermeier, C. G., da Fonseca, G. A. B. and Kent, J., Nature, 2000, 403, 853–858. 34. Pushpangadan, P. and Nair, K. S. S. (eds), Biodiversity and Tropical Forests – The Kerala Scenario, STEC, Govt of Kerala, 1997. 35. Nayar, M. P., Biodiversity challenges in Kerala and science of conservation biology. In Biodiversity of Tropical Forests – The Kerala Scenario (eds Pushpangadan, P. and Nair, K. S. S.), STEC, Govt of Kerala, 1997. 36. Nayar, M. P., Biodiversity and tropical forests – The Kerala Scenario. A compendium of background papers on the focal theme of the ninth Kerala Science Congress, 1997, The State Committee on Science, Technology and Environment, Kerala, 1997. 37. Sasidharan, N., Studies on the flora of Periyar Tiger Reserve. KFRI Research Report No. 128, KFRI, Peechi, 1997. 38. Sasidharan, N., Studies on the flora of Shendurney Wildlife Sanctuary. KFRI Research Report No. 150, KFRI, Peechi, 1998. 39. Nayar, M. P. and Sastry, A. R. K., Red Data Book on Indian Plants, Vols I–III, Botanical Survey of India, Calcutta, 1987, 1988, 1990. 40. Jain and Rao, Threatened plants of India. A state-of-the-art report, BSI, Calcutta, 1984. 41. Neelakandan, V. N. and Nair, M. M., Customization of Bio-Geographical Information System. Indian Cartogr., 2002, 22. 42. Nayar, M. P., Pushpangadan, P., Rajasekharan, S., Narayanan Nair, K. and Mathew Dan, Jaivavaividhyam (in Malayalam), State Institute of Language, Thiruvananthapuram, 2000. 43. Kathuria, S. and Ganeshaiah, K. N., Curr. Sci., 2002, 82, 76–81. 44. IUCN, Red List Categories, The World Conservation Union, Gland, Switzerland, 1994. 45. MoEF, National Biodiversity Strategy and Action Plan, October 2002, p. 53.
ACKNOWLEDGEMENTS. We thank Dr M. Baba, Director CESS, Thiruvananthapuram, for providing necessary facilities to carry out this work. We also thank Dr B. R. Ramesh, French Institute, Pondicherry, Drs N. Sasidharan, K. Vijayakumaran Nair and E. A. Jayson, Kerala Forest Research Institute, Trichur and Dr A. G. Pandurangan, Tropical Botanic Garden and Research Institute, Palode, for suggestions and 450
useful information. We are grateful to Prof. M. Balakrishnan, Department of Zoology, University of Kerala; Dr M. Kunhikrishnan, University College, Trivandrum and Dr Radhakrishnan, ZSI, Calicut for help. We thank the project staff K. Sriraj, B. Baijulal, and C. Anish for support in the preparation of spatial and bioresources database, and individuals and agencies who provided necessary data. We are grateful to the State Council for Science, Technology and Environment, Govt of Kerala for financial support.
Received 19 March 2005; revised accepted 27 October 2005
Developmental mode in white-nosed shrub frog Philautus cf. leucorhinus K. V. Gururaja and T. V. Ramachandra* Energy and Wetlands Research Group, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560 012, India
Direct development in amphibians bypassing intermediary tadpole stage has behavioural evolutionary and ecological significance. This paper presents direct development in Philautus cf. leucorhinus, while comparing with other congeners of the Western Ghats. Keywords: Amphibians, direct development, Philautus cf. leucorhinus, shrub frogs, Western Ghats. AMPHIBIANS exhibit remarkable variations in development from egg to adult. One such extreme modification is direct development, wherein free-swimming tadpole stage is completely eliminated and eggs hatch into baby frogs, resembling the adults except for their size. Species adapted completely to terrestrial living generally exhibit direct development. The advantage of being adapted to such development includes avoidance of predation, which is prevalent in aquatic media, parental care and more importantly, dependency on water body for development and complex metamorphic processes1. Direct development bypassing an aquatic, free-swimming tadpole stage in amphibians seems to be the fastest reproductive mechanism adapted in vertebrates and specifically among anamniotes2,3. Based on site of egg development, as many as 29 breeding types have been recorded in amphibians2. Nevertheless, direct development has an evolutionary significance in adapting to non-aquatic habitats, resembling oviparous development of birds and reptiles. The Western Ghats, a hill range on the west coast of India, with rich biodiversity harbours as many as 137 amphibian species. Among these, Philautus genus (Anura: Ranidae: Rhacophorinae), commonly known as Oriental shrub frog has direct development from egg to adult. *For correspondence. (e-mail:
[email protected]) CURRENT SCIENCE, VOL. 90, NO. 3, 10 FEBRUARY 2006
