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Human activities within the context of a drying trend triggered the megafaunal extinctions in Madagascar and Mascarene Islands., Madagascar and the Mascarene Islands of Mauritius and Rodrigues underwent catastrophic ecological and landscape transformations, which virtually eliminated their entire endemic vertebrate megafauna during the past millennium. These ecosystem changes have been alternately attributed to either human activities, climate change, or both, but parsing their relative importance, particularly in the case of Madagascar, has proven difficult. Here, we present a multimillennial (approximately the past 8000 years) reconstruction of the southwest Indian Ocean hydroclimate variability using speleothems from the island of Rodrigues, located ∼1600 km east of Madagascar. The record shows a recurring pattern of hydroclimate variability characterized by submillennial-scale drying trends, which were punctuated by decadal-to-multidecadal megadroughts, including during the late Holocene. Our data imply that the megafauna of the Mascarenes and Madagascar were resilient, enduring repeated past episodes of severe climate stress, but collapsed when a major increase in human activity occurred in the context of a prominent drying trend.

The “4.2 ka event” is frequently described as a major global climate anomaly between 4.2 and 3.9 ka, which defines the beginning of the current Meghalayan age in the Holocene epoch. The “event” has been disproportionately reported from proxy records from the Northern Hemisphere, but its climatic manifestation remains much less clear in the Southern Hemisphere. Here, we present highly resolved and chronologically well-constrained speleothem oxygen and carbon isotopes records between ∼6 and 3 ka from Rodrigues Island in the southwestern subtropical Indian Ocean, located ∼600 km east of Mauritius. Our records show that the 4.2 ka event did not manifest itself as a period of major climate change at Rodrigues Island in the context of our record's length. Instead, we find evidence for a multi-centennial drought that occurred near-continuously between 3.9 and 3.5 ka and temporally coincided with climate change throughout the Southern Hemisphere.

A Study conducted over a time span of two years on 304 subjects (152, non-diabetic and 152 diabetics) ended with some interesting outcome possibly due to the existing lifestyle of Raipur. During the study, by keeping the male and female in a ratio of 1:1. All the 304 subjects were divided into 4 different age groups. There fasting blood samples were tested for some biochemical parameters viz., plasma glucose and serum lipids. The diabetic patients showed a significant increasing trend in the values of Total Cholesterol, Triglycerides, VLDL and LDL and a significant decrease in the values of HDL as compared to that of non-diabetic subjects. The study showed the prevalence of hyperlipidemic conditions associated with diabetic patients whose intensity and horrific consequences are increasing along with age. The disorders related to lipid parameters occurred more in diabetic females perhaps indicating that the diabetic females of the area are more prone towards the development of cardiovascular diseases in the future. The possible reason behind each unusual findings have been tried correlate with the living style of the area.

Subterranean caves represent itself always a sterile ecosystem as it usually has very bleak connections with the external world. Due to complete lack of light, the existence of autotrophs become out of question inside the cave and whatever the organic energy sources get available inside the cave are mostly transported from the external world. Thus, most of the micro-fungi found inside the caves are also generally transported inside from some external agencies. Further, the available habitats inside the cave either abolish them completely or accelerate them to flourish. In the present study, we have tried to isolate the micro-fungi responsible for decaying the wood log inside a cave, Dandak of Chhattisgarh, India. Samples were collected from two different habitats of the cave, one which remains under the influence of external world (outer chamber) the other which is almost isolated from it (inner chamber). We found that besides some other genera of micro-fungi, the genus Aspergillus is dominating the decaying process of wood in the outer chamber whereas the genus Penicillium is dominating the same for the inner chamber.

The 4.2 ka BP event is widely described as a 200–300 years long interval of major climate anomaly (typically, arid and cooler conditions potentially across the globe), which defines the beginning of the current Meghalayan age in the Holocene epoch. The 4.2 ka event however, has been disproportionately reported from proxy records situated at low-mid latitudes in the Northern Hemisphere. Consequently, the climatic manifestation of the 4.2 ka event in both spatial and temporal domains is still much less clear in Southern Hemisphere. This is particularly the case for the southwest sector of the southern Indian Ocean. Here we present high-resolution and chronologically well-constrained speleothem oxygen and carbon isotopes records of hydroclimate variability between ~ 6 and 3 ka ago from Rodrigues Island, located in the southwest subtropical Indian Ocean, ~ 600 km east of Mauritius. Our records reveal a major shift to drier condition at circa 4 ka BP, which culminated into a multicentennial period of drought (i.e., megadrought) that lasted continuously from ~ 3.9 to 3.5 ka BP. The inferred hydroclimatic conditions between 4.0 and 4.2 ka BP, are however not distinctly distinguishable from the region’s mean hydroclimatic state over the length of our record. Because the precipitation variability at Rodrigues is distinctly modulated by meridional movement of the Inter-Tropical Convergence Zone and the El Nino Southern Oscillation dynamics, our proxy data may ultimately provide critical constraints in our understanding the timing and dynamical forcing of the 4.2 ka event.

Conventional weather-compensated heating controllers are often configured to deliver more heating than necessary, resulting in energy losses. Furthermore, they cannot take into account future climate conditions, and yield less than optimal thermal comfort. We have developed a non-invasive add-on module for existing heating controllers that implements an adaptive, model-predictive heating control algorithm. This algorithm helps the heating controller deliver a heating energy just sufficient for maintaining thermal comfort, resulting in energy savings. In this paper we report on the energy savings measured on ten buildings equipped with this device. By monitoring the space heating energy during the 2013–2014 heating season, and by periodically alternating between the new controller and the reference controller, we establish the energy signature of all buildings with both controllers. The comparison of the energy signatures yields the relative energy savings achievable with the new controller. These energy savings are positive for all test sites, with a mean of 28 ± 4% (standard error of the mean).

Deinococcus radiodurans is one of the most yet discovered extremophilic microbe, the isolation of which from the various habitats of Kotumsar cave is always a matter of enticement to discover its ecological economics. In the present work we studied the intra versus extracellular alkaline protease and glucose isomerase secretion capabilities of Deinococcus radiodurans; KCB21, KCB50, KCB93 isolated from three distinct subterranean niches of Kotumsar cave. The selected niches/zones were the entrance zone, transient zone and the deep inner zone from where the soil sediments were collected to isolate the bacterial strains. The results revealed high extracellular alkaline protease activity from the Deinococcus radiodurans strain which was isolated from the deeper zones of the cave, whereas no such phenomenon was revealed for glucose isomerase. The possible reason for the obtained results has been discussed.

Background: Candida albicans is the commonly associated species with oral lesions, but other Candida spp., such as C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, and C. dubliniensis have also been isolated from the human saliva, even irrespective to the oral candidiasis. Candidal colonization has also been documented from subgingival plaque of adults with periodontitis. Objective: Nowadays there is a great demand of natural herbal medicines. For a Diabetic person having Periodontitis, the use antifungal drugs are must. Therefore the antifungal capacity of the commonly used drug and herbs has been evaluated. Methods: For the study, the patients were screened and categorised into two study and one control group, having 20 patients in each group, on the basis of their respective Blood Glucose level and Dental status using standard clinical parameters. Oral rinse of 60 patients including both gender were selected from the Out Patient Department of Periodontitis, Rungta College of Dental Sciences and Research, Chhattisgarh. Chrome Candida Agar Media was used to identify Candida albicans and NAC. In vitro tests of the effectiveness of selected antimycotic agents against test candidal isolates recovered from the patient were performed to check the efficacy of the antifungal agents by the Kirby-Bauer Disc Diffusion method. Result: We found that by the use of this chromogenic media most of the commonly recovered NAC can be easily distinguished as each species produced the widest range of colours and morphologies. The herbal extracts Aloe Vera and Garlic failed to inhibit the growth of the candidal species but Neem, Meetha Neem, Triphala, Tulsi showed sensitivity to varying degree. Now a day there are much popularity of using herbal products, having its extracts incorporated in the cosmetics and other products used by humans. Conclusion: We conducted the sensitivity check of the candidal isolates against the dental dentrifices and found that however all the toothpastes contained herbal extracts capable of destroying bacteria but it did not showed good results against candidal species except the Patanjali Toothpaste. This may be due the fact that Patanjali Dant Kanti Dental Cream has the combination of all the herbal extract mixed altogether. DOI: http://dx.doi.org/10.3126/ijosh.v4i1.12164

Tunnel caves are such passages, usually formed in the foothill of any mountain and mutually connect two plateaus. Such caves are large enough to accommodate the sizable amount of human beings and/or animals but do not meet all the criteria which are required to define a true cave (Vandel, 1965; Ford & Cullingford, 1976). Perhaps the geological processes of formation of such structures are the same as the other adjacent true caves. In essence, the complete dark zones are usually absent in tunnel caves due to which constant geophysical characteristics never develops. However, up to far extent tunnel caves also harbor the same biotic components which are usually common in the other true caves exist elsewhere.

The life in subterranean caves always needs a high degree of biological adaptability, due to its unusual ecosystem. The cave dwelling species usually get selected from preadapted biological traits for cave life. The cave dwelling tendencies in frog are very uncommon. Majority of reported cave frogs usually prefer cave for temporary shelter. In India, the biospeleological inventory is still in its primary stage. Till date no serious attempt has been taken to understand the cave dwelling habitat for any frog in India. Inspite of it, in India time to time various reports on natural histories of anurans reveal its cave dwelling tendencies. On the basis of personal observations and available literature in this report I have documented the occurrences and distributions of five cave dwelling frogs of India. Common biological traits from all the established cave frogs, which could be referred as preadapted for cave life, have been discussed. Further, the possible threats and IUCN status of each discussed species has been highlighted.

There are a number of clear examples in the instrumental period where positive El Niño–Southern Oscillation (ENSO) events were coincident with a severely weakened Indian summer monsoon (ISM). ENSO's influence on ISM precipitation has therefore remained the centerpiece of various predictive schemes of ISM rainfall for over a century. The teleconnection between ISM precipitation and ENSO has undergone a protracted weakening since the late 1980s, suggesting the strength of ENSO's influence on ISM precipitation may vary on multidecadal timescales. The recent weakening has occurred despite the fact that the ENSO system has experienced variance levels during the latter part of the 20th century that are as high as any period in the past millennium. The recent change in the ENSO–ISM coupling has prompted questions as to whether this shift represents a natural mode of climate variability or a fundamental change in ENSO and/or ISM dynamics due to anthropogenic warming or aerosol impacts on the ISM. Here we place the 20th century ENSO–ISM relationship in a millennial context by assessing the phase relationship between the two systems across the time spectrum using a a series of high-resolution reconstructions of ENSO and the ISM from tree rings, speleothems and corals. The results from all the proxies suggest that in the high-frequency domain (5–15 yr), warm (cool) sea surface temperatures in the eastern tropical Pacific lead to a weakened (strengthened) monsoon. This finding is consistent with the observed relationship between the two systems during the instrumental period. However, in the multidecadal domain (30–90 yr) the phasing between the systems is reversed such that periods of strong monsoons were, in general, coincident with periods of enhanced ENSO variability. This result is counterintuitive to the expectation that enhanced ENSO variance favors an asymmetric increase in the frequency of El Niño events and therefore a weakened monsoon system. The finding implies that the prominent multidecadal variability that characterizes the last 1000 yr of the ISM is not likely attributable to multidecadal shifts in ENSO. If there is a continued trend towards enhanced ENSO variance in the coming decades, the results presented here do not suggest this will force a reduction in ISM precipitation.

The evolutionary adaptations of the organisms which inhabit the unusual and fragile ecosystems within caves are of inherent interest to both biologists and laymen. Cave organisms generally develop a high degree of physiological and behavioural adaptation for survival in the subterranean environment. The Kotumsar Cave is biologically the best known cave in India and has attracted interest from researchers from all over the world. This paper assesses the ecological community and overall habitat of the cave. This is based on long-term field observations and the review of the extensive literature on Kotumsar. For each species, features indicative of evolutionary adaptation to the cave environment are noted and conclusions drawn regarding the status of the species as a cavernicole. Several species of this cave are yet to get a proper study for correct taxonomic position although they have apparent troglomorphic dispositions. Several species which are highly endemic to this cave are probably in verge of its extinction. A serious measure to conserve the whole biodiversity has been suggested.

Subterranean cave ecosystems are characterized by perpetual darkness, almost constant ambient temperature, limited source of food supply and relatively high humidity. The occurrence of circadian rhythms in organisms living in such an ecosystem always attracts chronobiologists to understand the phenomena of time-measuring mechanisms. Few attempts have been made to correlate such rhythmic patterns of the organism with the putative periodicities in weak zeitgebers. In the present study, the effects of periodic feeding schedules on the characteristics of circadian rhythm in the vertical swimming activity of the cave loach Nemacheilus evezardi were examined. Results reveal that periodic feeding at 18:00 has the ability to synchronize the vertical swimming activity rhythm. It seems that periodic restricted feeding could act as a powerful zeitgeber of circadian rhythms in subterranean organisms.

[1] The “internally” generated intraseasonal variability of the Indian Summer Monsoon is characterized by intermittent periods of enhanced (“active”) and deficient (“break”) precipitation, which produce a quasi east-west precipitation dipole over the Indian subcontinent. Here we present multicentennial-length and near annually-resolved reconstructions of monsoon precipitation, inferred from absolute-dated and instrumentally calibrated speleothem oxygen isotope records from regions (central and northeast India) that have diametric responses to active-break monsoon circulation patterns. On centennial timescales (AD 1400–2008), precipitation variability from these two regions exhibit opposing behavior, oscillating between periods with a persistently “active-dominated” (AD ∼1700 to 2007) and a “break-dominated” (AD 1400 to ∼1700) regime. The switch between these regimes occurs abruptly (within decades) at a time (AD ∼ 1650–1700) when a proxy record of upwelling intensity from the Arabian Sea suggest an abrupt increase in the monsoon winds. On the basis of these observations, we hypothesize that the frequency distribution of active-break periods varies on centennial timescales, implying a leading role of internal dynamics in governing the ISM response to slowly-evolving changes in the external boundary conditions.

The Mandhhip Khhol-Pyton cave, located in an area declared Protected Forest in thhe Rajnandgaon District about 7 km in a direct line WwNWw from thhe village of Thakurtola (N21°39’:E080°58’), consists of an upper level orientated essentially along NE-SWw and NNWw-SSE fracture systems, subsequently connected thhroughh a NE-SWw structure withh an independent karst system, at a lower level orientated predominantly along bedding planes. The speleogenesis controlled by various structuralelements hhas manifested itself as hhaving different morphhologiesin thhe two levels. In fact, fracture-controlled vadose passages prevail in thhe upper level, whhile water flow along thhe bedding planes in thhe lower level caused morphhologies chharacterized by wide but low passages. The studied system constitutes a particular example of karst morphhologies developedin a lenticular limestone formation withhin phhyllite rocks of Precambrian metamorphhic age. Keywords: India, Chhhhattisgarhh, karst, speleogenesis, Mandhhip Khhol.

Study of the biological rhythms in cavernicoles is of considerable interest especially since the cave ecosystem is characterized by absence of light, relatively constant temperature and relatively high and constant humidity. The present paper documents for the first time multifrequency biologic rhythms in air gulping behaviour of a cavernicolous fish Oreonectus evezardi, kept under complete darkness, DD. A circadian rhythm was demonstrated with statistical significance by cosinor method for air‐gulping activity during 9 months out of 14 months of observations. A 6‐monthly rhythm in circadian mesor was detected. However, statistically significant circannual rhythms in circadian amplitude and circadian acrophase were validated. Thus, results of the present study clearly demonstrate semicircannual or circannual modulation of the circadian behavioural rhythm of a cave dwelling teleost.

Observations show that summer rainfall over large parts of South Asia has declined over the past five to six decades. It remains unclear, however, whether this trend is due to natural variability or increased anthropogenic aerosol loading over South Asia. Here we use stable oxygen isotopes in speleothems from northern India to reconstruct variations in Indian monsoon rainfall over the last two millennia. We find that within the long-term context of our record, the current drying trend is not outside the envelope of monsoon's oscillatory variability, albeit at the lower edge of this variance. Furthermore, the magnitude of multi-decadal oscillatory variability in monsoon rainfall inferred from our proxy record is comparable to model estimates of anthropogenic-forced trends of mean monsoon rainfall in the 21st century under various emission scenarios. Our results suggest that anthropogenic-forced changes in monsoon rainfall will remain difficult to detect against a backdrop of large natural variability.

Erythropoietic responses of fed and starved species of teleosts, viz., Clarias batrachus and Heteropneustes fossilis , to human urinary erythropoietin and thyroxine have been examined. The effects of these hormones on energy reserves have also been evaluated. Twenty-four C. batrachus were divided into two groups: half were fed regularly; the remaining fish were starved 20 days. On the 21st day each group was further divided into three subgroups of four each and received either saline, thyroxine (8 μg), or erythropoietin (6 IU) over 4 consecutive days. The experimental protocol was identical for H. fossilis ; however, for H. fossilis two identical studies were conducted approximately 1 year apart. A decline in the rate of erythropoiesis and a stimulatory response to human urinary erythropoietin followed starvation in both species of teleosts. In addition, erythropoietin had a pronounced effect on hepatic glycogenesis of fed H. fossilis and stimulated erythropoiesis in the fed teleosts of both species. Prolonged starvation drastically depleted hepatic glycogen in C. batrachus . In contrast, it had no effect on hepatic glycogen in H. fossilis and on muscle glycogen and protein in both species. In general, while both species could respond to erythropoietin and withstand prolonged starvation, H. fossilis alone exhibited remarkable tolerance to fasting.

Ruedi, Manuel, Biswas, Jayant, Csorba, Gábor (2012): Bats from the wet: two new species of Tube-nosed bats (Chiroptera: Vespertilionidae) from Meghalaya, India. Revue suisse de Zoologie 119 (1): 111-135, DOI: 10.5962/bhl.part.150145, URL: http://www.biodiversitylibrary.org/part/150145

Background and Objectives: In the last few decades, losses of our cultural heritage due to biodeteriorationare beinghighly recognized. From museum objects to rock monuments, the microbial biodeterioration agents are found to be the most destructive. Possibilities for proper preservative measure(s) are always more when it is only a monument, statue, museum article, or pre-historic art in any small subterranean cave. Nevertheless, preservation/protection of the footprints occupying a big area, lying scattered in a very negligible manner requires safeguard against several deterioration factors; right from various physical, chemical and biological agents which are indeed interrelated to each other. Materials and Methods: In the present study, some microbial communities possibly responsible for deteriorating the rocks of Kabra-pahad, where the most famous pre-historic rock paints of India prevail have been identified. The diversity of fungi and bacteria present in the stone crust of the infected areas has been studied by employing standard laboratory methods. Results:The cultivated cultures confirmed total fifteen fungal species, among which Aspergillus group were the most dominant. Among bacteria, total 80 numbers of colonies were observed that dominated by two major groups; Micrococcus. spp and Staphylococcus spp. Conclusion: The pre-historic footprint in the form of rock paints in Kabra-pahad of district Raigarh, Chhattisgarh, India is lying in a very deteriorated manner. In the present study, we have tried to identify few major deteriorating factors that are responsible for such degradation of our existing pre-historic footprints.