SAMANAR CAVE, Nagamalai 1

Herbert Daniel Gebauer - 06/01/2018

One single (KOILRAJ, SHARMA et al. 2000: 759), south-east facing (KOILRAJ & MARIMUTHU 1998: 1111), crawl-sized (CHANDRASHEKARAN 2003: 8) cave entrance (unidentified dimensions) leads to one (note 1) out of eight natural caves (TUTTLE & CHANDRASHEKARAN 1987: 6) in foliated biotite gneiss, which is probably a gneissose granite (IMPERIAL GAZETTEER 1907-1909, 16: 387-388) occuring on Samanar Malai (Samanar Hill), the Jain Hill west of Madurai city: Samanar Hill rises from the surrounding fields, a mass of rock composed largely of granite. Inside, the hill is honey-combed with caves, important archeological sites as well as homes for thousands of insectivorous bats of nine species. Distributed among eight caves, these bats have likely roosted in Samanar Hill for thousands of years, critical contributors to the health of the local environment (TUTTLE & CHANDRASHEKARAN 1987: 6). The entrance to one natural cave leads to a single chamber (MARIMUTHU, RAJAN & CHANDRASHEKARAN 1981) with a dark zne (note 2) at estimated distances ranging from more than 15 m (KOILRAJ & MARIMUTHU 1998: 1112) and 30 m (MARIMUTHU, SUBBARAJ & CHANDRASHEKARAN 1978: 600) to 35 m (KOILRAJ, SHARMA et al. 2000: 759) or 40 m (MARIMUTHU & CHANDRASHEKARAN 1983: 620) from the entrance. ETYMOLOGY: In Tamil, the Jain (Jaina) community is called samanar (shramana) (Vijaya Sherry Chand, Indian Institute of Management, Ahmedabad 380 015, on iimahd.ernet.in/~vijaya/sit.htm accessed 2008.06.01). SITUATION 1983: Around our university complex (9°58' N, 78°10' E) (note 3) (MARIMUTHU & CHANDRASHEKARAN 1983: 620). SITUATION 1987: In southern India near Madurai (TUTTLE & CHANDRASHEKARAN 1987: 6). SITUATION 1998: At an unidentified location lies Samanar Cave … within a radius of about 10 km from Madurai Kamaraj University campus (9°58 N, 78°10' E) (KOILRAJ & MARIMUTHU 1998: 1111). SITUATION 1999: The Samanar Cave at Madurai (lat. 9°58'N, long. 78°10'E) (KOILRAJ & MARIMUTHU 1999). Both (1) Samanar Cave and The amanar cave is [facing?] towards to the south-east … and is at a distance of about 10 km from the Madurai Kamaraj University campus (9°58'N, 78°10'E) (KOILRAJ, MARIMUTHU et al. 1999). SITUATION 2000: The entire Samanar hill complex in India [lies] about 8 km [probably along a road] south-east of Madurai Kamaraj University campus (9°58 N, 78°10' E) (KOILRAJ, SHARMA et al. 2000: 759). … a true cave … in Samanar Hills, 8 km from the Madurai Kamaraj University campus (9°58'N; 78°10'E) (CHANDRASHEKARAN 2002: 899).SITUATION 2003: There are … vital bat caves in Samanar Hill in southern India (MISTRY 2003: 9). SITUATION 2004: Samanar Malai … [lies] about 8 km from Madurai (LALJAPATI ROY (2004.06.05). SITUATION 2005: CHANDRASHEKARAN (2005: 2) narrates to have reached in summer 1978 the Jain Hills caves (the caves on Samanar Malai) by travelling about 7 km on the Madurai (N09°55': E078°07'30”) - Bodinayakanur (N10°01': E077°21') passenger train up to the Nagamalai - Pudukkotta unmanned rail stop (note 4). SITUATION 2006: … Jain caves are located amid serene surroundings of green fields, atop Samana Malai … about 10 km west of the city [of Madurai, and] near Keezhakuyilkudi village [note 5] (SAIRAM 2006.09.27). CAVE DESCRIPTION 1978: The deeper recesses of the cave, ca. 30 m from the cave mouth, show invariant temperature (27°C) and humidity (95%) and the darkness is absolute (a UDT optometer does not measure any light on the energy scale for 1000 s) (MARIMUTHU, SUBBARAJ & CHANDRASHEKARAN 1978: 600). CAVE DESCRIPTION 2003: … the cave of the Samanar Hills in Madurai, in which G. Marimuthu and I worked, the entrance to which was so small that we had to file in one after the other, legs first (CHANDRASHEKARAN 2003a: 8). CHANDRASHEKARAN (2003b) reports to have been Working at a depth of 40 m in a natural cave … (no name mentioned). CAVE CLIMATE: According to KOILRAJ & MARIMUTHU (1998: 1111) and KOILRAJ et al (1999) it was MARIMUTHU & CHANDRASHEKARAN (1983), MARMUTHU (1984: 352-357), USMAN (1981 PhD thesis) and HABERSETZER (1983 PhD thesis) who recorded temperature, humidity, relative humidity and light intensity) for a period of one year (September 1997 to August 1998). Both MARIMUTHU, SUBBARAJ & CHANDRASHEKARAN (1978: 600) and KOILRAJ & MARIMUTHU (1999: 1112 table 1) report to have found constant values of cave temperature (27°C) and humidity (95%) at the dark zone more than 15 m from the entrance. KOILRAJ, SHARMA et al. (2000: 759) report a temperature of 27°C (±0.5°C) and a relative humidity of 95% (Oakton hygrothermograph, Wilb. Lambrecht KG, Göttingen, Germany). CAVE LIFE: MARIMUTHU, SUBBARAJ & CHANDRASHEKARAN (1978: 600) … investigated whether a bat 'trapped' in such an invariant [and] time-cue-less environment would still be able to tell time. Red light (600 nm), an infrared source, and noctovision were employed in conducting the experiments. The bats wre hand-fed daily with minced cock-roaches. Figure 1 shows the flight pattern f a [female Hipposideros speoris Schneider 1800, insectivorous] trapped bat in a cage (30 x 30 x 30 cm) suspended by a sturdy spring. The flight movements set the cage in gentle motion which were [was?] traced on a mechanically wound drum with felt-tipped stylets. There is a clear-cut rhythmicity in the activity which is (a) 'entrained' and (b) bimodal. Circadian rythms in bats entrain to light-dark cycles and in the absence of such a Zeitgeber influence they run free. The rythm of our captive bat clearly entrains and displays the strict 24-h periodicity of the light-sampling bats. We conclude that this entrainment has arisen through the process of 'social synchronisation' wherein the free-flyingconspecifics transmit the message of timing … MARIMUTHU, RAJAN & CHANDRASHEKARAN (1981) studied social entrainment of bats (Chiroptera: Microchiroptera: Hipposideros speoris Schneider 1800). MARIMUTHU & CHANDRASHEKARAN (1983) kept four alien bats (Chiroptera: Taphozous nudiventris kachensis) confined for 60 days inside cages (30 cm egde cubicle) put up 40 m from the entrance to a dark cave (no name mentioned), which was inhabited by a colony of at least 500 individuals of Hipposideros speoris. The caged bats failed to entrain their activity / rest pattern to that of the free-flying members of the colony: It is tempting to postulate that a certain degree of species specificity might be involved in social entrainment of circadian rythms among microchiropteran bats. KOILRAJ (1992 Mss: M. Sc. dissertation) made Histological studies on the frontal gland and breeding behavior of the leaf-nosed bat Hipposideros speoris.- KOILRAJ & MARIMUTHU (1998: 1112 table 2) report that a one Mrs. Elizabeth (no name mentioned: Varghese?) reared algae from soil samples collected in the daylight-lit area 0 to 5 m from the entrance: Three species of Chlorophyceae (Chlorella sp., Chlorococcum sp., Scenedesmus sp.) and four species of Bacillariophyceae (Cyclotella sp., Navicula sp., Nitzscha sp., Surirella sp). KOILRAJ & MARIMUTHU (1999: 339-340) compared three specimens of adult cave millipede Glyphiulus cavernicolus (body length 40.4 ± 2.8 mm; body weight 78.3 ± 7.6 mg; n = 30) from Samanar cave with the free living millipede Syngalobolus sp. (body length, 45.8 ± 2.4 mm; body weight 93.0 ± 12.0 mg; n = 18) living near the cave entrance. The troglobitic millipede contained only 7 ommatidia in each eye spot whereas, the surface dwelling millipede possessed 28 ommatidia per eye spot. The body surface of the troglobitic millipedes was lobular with thick projections all over the body; but the body surface of the epigean millipedes was soft and flat. KOILRAJ, SHARMA et al. (2000: 757-765) monitored the locomotor activity of the millipede Glyphiulus cavernicolus (Cambalidae, Spirostreptida) which lives in the darker recesses of a natural cave (with one single opening … in the Samanar hill complex or Samanar Malai), is nearly dull white in colour (40.4 ±2.8 mm long, about 2 m wide), found all over the deeper and darker reas of the cave (page 759), and supposed to have been from time unknown never exposed to any periodic factors of the environment such as light-dark, temperature, humidity, etc but nevertheless entertained a circadian rythm, which was interpreted as the capacity to measure time and to respond to light and dark situations. KOILRAJ, SHARMA et al. (2000: 759): A colony of about 500 insectivorous bats, Hipposideros speoris, uses this cave as their daytime roosting place. Apart from bats, spiders, flies, insects, millipedes, centipedes, scorpions, snakes (seen only at the entrance chamber), and shrews also live inside this cave. CHANDRASHEKARAN (2002: 899): … was inside a true cave watching a colony of bats in Samanar Hills, 8 km from the Madurai Kamaraj University campus (9°58'N; 78°10'E) when a solar eclipse plunged Africa and parts of Asia into a twilight state of darkness for 4 min 8 s on 16 February 1980. Then onwards I could truthfullysay ‘Nothing happened to my bats during the solar eclipse. They all still roosted inside the cave upside down’. CHANDRASHEKARAN (2003b abstract): Working at a depth of 40 m in a natural cave [no name mentioned: most likely: Samanar Cave], we discovered that there is mutual social synchronisation of the circadian rhythm underlying the exodus flight of a colony of circa 600 Hipposideros speoris bats around the local sunset time. The circadian rhythm in the flight/rest activity of a solitary bat in a solitary cave without other conspecifics (social informers) free-ran. We also report here results of experiments with H. speoris showing that daylight dimmer than starlight (0.0001 to 0.0006 lux) streaming into a cave for c. 90 mins could entrain their circadian rhythm. H. speoris is very sensitive to light, and light flashes lasting only 0.0625 msecs could shift the phases of the circadian rhythm. The spectral sensitivity of the photoreceptors in H speoris indicates that they have colour viion. There is annual breeding periodicity in Hipposideros speoris.say ‘Nothing happened to my bats during the solar eclipse. They all still roosted inside the cave upside down’. CHANDRASHEKARAN (2003b abstract): Working at a depth of 40 m in a natural cave [no name mentioned: most likely: Samanar Cave], we discovered that there is mutual social synchronisation of the circadian rhythm underlying the exodus flight of a colony of circa 600 Hipposideros speoris bats around the local sunset time. The circadian rhythm in the flight/rest activity of a solitary bat in a solitary cave without other conspecifics (social informers) free-ran. We also report here results of experiments with H. speoris showing that daylight dimmer than starlight (0.0001 to 0.0006 lux) streaming into a cave for c. 90 mins could entrain their circadian rhythm. H. speoris is very sensitive to light, and light flashes lasting only 0.0625 msecs could shift the phases of the circadian rhythm. The spectral sensitivity of the photoreceptors in H speoris indicates that they have colour visay ‘Nothing happened to my bats during the solar eclipse. They all still roosted inside the cave upside down’. CHANDRASHEKARAN (2003b abstract): Working at a depth of 40 m in a natural cave [no name mentioned: most likely: Samanar Cave], we discovered that there is mutual social synchronisation of the circadian rhythm underlying the exodus flight of a colony of circa 600 Hipposideros speoris bats around the local sunset time. The circadian rhythm in the flight/rest activity of a solitary bat in a solitary cave without other conspecifics (social informers) free-ran. We also report here results of experiments with H. speoris showing that daylight dimmer than starlight (0.0001 to 0.0006 lux) streaming into a cave for c. 90 mins could entrain their circadian rhythm. H. speoris is very sensitive to light, and light flashes lasting only 0.0625 msecs could shift the phases of the circadian rhythm. The spectral sensitivity of the photoreceptors in H speoris indicates that they have colour visay ‘Nothing happened to my bats during the solar eclipse. They all still roosted inside the cave upside down’. CHANDRASHEKARAN (2003b abstract): Working at a depth of 40 m in a natural cave [no name mentioned: most likely: Samanar Cave], we discovered that there is mutual social synchronisation of the circadian rhythm underlying the exodus flight of a colony of circa 600 Hipposideros speoris bats around the local sunset time. The circadian rhythm in the flight/rest activity of a solitary bat in a solitary cave without other conspecifics (social informers) free-ran. We also report here results of experiments with H. speoris showing that daylight dimmer than starlight (0.0001 to 0.0006 lux) streaming into a cave for c. 90 mins could entrain their circadian rhythm. H. speoris is very sensitive to light, and light flashes lasting only 0.0625 msecs could shift the phases of the circadian rhythm. The spectral sensitivity of the photoreceptors in H speoris indicates that they have colour visay ‘Nothing happened to my bats during the solar eclipse. They all still roosted inside the cave upside down’. CHANDRASHEKARAN (2003b abstract): Working at a depth of 40 m in a natural cave [no name mentioned: most likely: Samanar Cave], we discovered that there is mutual social synchronisation of the circadian rhythm underlying the exodus flight of a colony of circa 600 Hipposideros speoris bats around the local sunset time. The circadian rhythm in the flight/rest activity of a solitary bat in a solitary cave without other conspecifics (social informers) free-ran. We also report here results of experiments with H. speoris showing that daylight dimmer than starlight (0.0001 to 0.0006 lux) streaming into a cave for c. 90 mins could entrain their circadian rhythm. H. speoris is very sensitive to light, and light flashes lasting only 0.0625 msecs could shift the phases of the circadian rhythm. The spectral sensitivity of the photoreceptors in H speoris indicates that they have colour viion. There is annual breeding periodicity in Hipposideros speoris.