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Aich, Anulipi
- Expression of Hepatic Metallothionein in Guppy Fish (Poecilia reticulata) Exposed to Composite Tannery Wastewater
Authors
1 Govt. College of Engineering and Leather Technology, LBIII, Salt Lake, Kolkata-700 098, West Bengal, IN
Source
Journal of Environment and Sociobiology, Vol 12, No Sp Iss (2015), Pagination: 31-31Abstract
Throughout the year composite industrial and municipal wastewater contaminate the East Calcutta Wetlands (ECW; lat.22°33' - 22°40'N; long. 88°25' - 88°35'E), a special conservation site (Ramsar Site No.1208), in Kolkata city, West Bengal, India. Tannery wastewater is mainly characterized by high salinity, high organic loading and harmful heavy metals, especially chromium. However, the composite wastewater discharges are being productively utilized in the aquaculture after stabilization and also being used to irrigate adjoining farmlands. Industrial discharges in aquatic bodies may lead to increased concentrations of toxic chemicals and elements including heavy metals in the medium, which in turn affects the freshwater food-web. The liver is a vital organ that plays an important role in metabolic processes by the way of detoxifcation of xenobiotics. Present study was conducted to record the bioaccumulation of metals in a fish (Guppy; Poecilia reticulata) biosystem when exposed to composite tannery effuent. The 96-h LC50 tests were conducted to measure the vulnerability of fish to composite tannery wastewater. The present study was also undertaken to determine the cell-types that exhibited metallothionein (MT) expression in liver tissue of guppy fish survived in sub-lethal dose of composite tannery effuent. It was evident from the study that metal concentration was higher in tannery effuent exposed fish in comparison to the unexposed fish (control fish where no tannery effuent was mixed). Immuno Electron microscopic study for the presence of metallothionein in treated fish along with the control specimen showed signifcant induction of fish hepatic MT under sub-lethal exposure to tannery effuent. Metalloprotein complexes sequester firmly the extra loads of metals in liver and thereby hinder the infuences of hazardous metals in fish biosystem. Hence, the induction of fish hepatic MTs could be conveniently employed as biomarkers for metal contamination.- Diel Changes in the Avian Community at the Edge of a Shola Forest of Western Ghat
Authors
1 Department of Zoology, Maulana Azad College, Kolkata-700 013, IN
Source
Journal of Environment and Sociobiology, Vol 2, No 1-2 (2005), Pagination: 9-14Abstract
Die! changes in avifaunal activities were studied at tine edge of a stiola forest patch belonging to Silent Valley National Park in the southern part of Western Ghat range of Kerala. Twentytwo species of birds under 15 families were recorded to be active at the study site. Highest population density of 19.46 ha-1 in the evening was recorded while in the morning the density was 9.42 ha-1. Under 12 families. 19 species were detected in the evening, while only 8 species under 7 families were found in the morning count. A higher diversity index (2.706), recorded from the evening counts, indicates less dominance (0.089) and more evenness (0.955) in comparison with morning counts where diversity estimated at 1.972 emphasises minimum evenness (0.948) and maximum dominance (0.219).Keywords
Shola, Diel Change, Birds, Western Ghats, Hotspot.- Evolutionary Arms Race:A Review on the Red Queen Hypothesis
Authors
1 Department of Zoology, Maulana Azad College, Kolkata, IN
Source
Journal of Environment and Sociobiology, Vol 2, No 1-2 (2005), Pagination: 109-118Abstract
Leigh Van Valen (1973), an evolutionary biologist of the University of Chicago, devised Red Queen hypothesis stating : "for an evolutionary system continuing development is needed in order to maintain its titness relative to the system it is co-evolving with." This hypothesis maintains that biotic interactions are most important drivers of evolutionary changes. On the other hand. Court Jester hypothesis, a class of alternative ideas to Red Queen, regards physicalenvironment perturbations as indicators of major changes in organisms and ecosystem.
From evolutionary point of view, sexual reproduction is not most efficient way of reproducing due to major investment of time and energy for fmding a male. Rather, for spreading genes from one generation to the next asexually reproducing organisms have an edge. Because in sexual reproduction half of the genes from each parent is handed over to the next generation. In this context. Red Queen hypothesis talks about evolution of sex and recombination. This hypothesis describes two similar ideas that (i) co-evolution can lead to situations for which the probability of extinction is relatively constant over millions of years and that (ii) coevolution, more particularly between hosts and parasites, could lead to sustained oscillations in genotype frequencies. According to this hypothesis the species had to "run" (evolve) a leg race instead of an arms race" in order to slay in the same place (extant). The Red Queen hypothesis emphasises the biotic interaction that imposes changes in species and clearly indicates the necessity of sexual reproduction in compaiison with asexual reproduction for stabilising the evolution of sex and recombination.
Keywords
Red Queen Hypothesis, Evohttionary Arms Race, Co-Evolution, Court- Jester Hypothesis, Milankovitch Oscillation.- Co-Operation as an Evolutionary Consequence
Authors
1 Government College of Engineering and Leather Technology, LB Block, Sector-Ill, Kolkata-700 098, IN