Animal Adaptations: Evolution of Forms and Functions

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Neha Saxena, a film actress who acts mainly Malayalam, Kannada, Tamil and Telugu, Hindi language films Almost all animals inhabiting natural environments are exposed to changes in important climatic factors like temperature, rainfall, humidity and photoperiod. It is these factors on which they rely to cue changes in their sexual status, and an interaction between them and the sexual activity has been reported ( Pevet, 1985a, b; Pevet et al., 1987; Vivien-Roles and Pevet, 1983). The pineal gland has been shown to be involved in the long term adaptation of animal to seasonal reproduction ( Pevet, 1985b; Reiter, 1985). The MI synthesized by the pineal gland act on the hypothalamo-hypophysealgonadal axis and may exert a stimulatory, inhibitory or no effect on the gonads depending on their mode and time of administration ( Berndtson et al., 1974; Ebels et al., 1965; Hoffmann, 1981a; Peat et al., 1971; Turek et al., 1975). The pineal gland of F. pennanti, a tropical seasonal breeder, is sensitive to environmental daylength, temperature and humidity ( Haldar et al., 1988; Haldar et al., 1990). Evening injections of MI inhibit testicular activity of this rodent ( Saxena et al., 1992; Saxena, 1997). Day-night variations in plasma aMT suggest the existence of a diurnal rhythmi- city in pineal activity of this mammal ( Saxena et al., 1993). Haematological analysis: From the respective groups above, four mice were sacrificed from each of the groups on days 3, 8 and 14 post-infection and blood samples collected in heparinized sample bottles were submitted for haematological examination.

Dyer, S. J., O’Neill, J. P., Wasel, S. M. & Boutin, S. Quantifying barrier effects of roads and seismic lines on movement of female woodland caribou in northeastern Alberta. Can. J. Zool. 80, 839–845 (2002). At higher traffic volumes the barrier effect sets in due to continuous flow of traffic, where road crossing by animals may not occur. Thus higher traffic volumes would result in a barrier-like situation because of avoidance of animals at high traffic segments 6, 7 reducing the number of attempted crossings by wildlife. This avoidance would reflect as low roadkill counts on high traffic roads 22.

The transportation infrastructure of a nation is vital for its social and economic growth, especially for a developing economy. However, the construction and operation of roads come at great costs to wildlife and forests dissected by linear infrastructure 1, 2. The most conspicuous impact of roads is wildlife-vehicle collisions, which is a major cause of decline in animal populations in human-dominated landscapes 3. Road-related mortality affects animal populations more adversely than natural mortality since it is non-selective, and affects healthy and unhealthy individuals of a population equally 4, 5.

Johnsingh, A. J. T. & Manjrekar, N. (eds) Mammals of South Asia (Universities Press, Hyderabad, 2015).We placed vehicle input points at the beginning of the link, and data collection points midway along the road, and specified the hourly traffic volume at each vehicle input point. The average harmonic speed of traffic flow at each traffic volume and free flow speeds of different traffic components were selected as data collection measurement attributes (outputs of the simulation). Each simulation was run for 600 s (10 min) with 20 replicates. Simulation resolution of 10 time steps/second was set to maximize speed data collection at data collection points. Species characteristics Bains, M. S., Ponnu, B. & Arkatkar, S. S. Modeling of traffic flow on Indian expressways using simulation technique. Procedia Soc. Behav. Sci. 43, 475–493. https://doi.org/10.1016/j.sbspro.2012.04.121 (2012).

The model assumes that traversing of roads by animals is ‘blind’ for animals in that they do not respond to the presence of vehicles (i.e. do not stop or turn around), and for drivers in that they do not respond to the presence of animals on the road by braking. Therefore, we define P h as the probability of hit of an animal that is attempting to cross the road, as we cannot account for the number of crossing attempts that translate into actual presence of animal on the road for an AVC to occur. Arasan, V. T. & Koshy, R. Z. Headway distribution of heterogeneous traffic on urban arterials. J. Inst. Eng. (India) 84, 210–215 (2003). Shepard, D. B., Kuhns, A. R., Dreslik, M. J. & Philips, C. A. Roads as barriers to animal movement in fragmented landscapes. Anim. Conserv. 11, 288–296. https://doi.org/10.1111/j.1469-1795.2008.00183.x (2008). Avadh Saxena, the American Group Leader of Physics of Condensed Matter and Complex Systems Group (T-4) at Los Alamos National Laboratory The present study reveals, for the first time in a tropical mammalian species, that besides aMT there also exists a diurnal rhythm in the sensitivity of the animal to exogenous MT injections. Pinealecomy and constant release of aMT and MT have been reported to cause atrophy of gonad in male European hamsters kept under long photoperiod ( Masson-Pevet et al., 1986). aMT implants have been reported to hasten recrudescence in male hamsters on short days (Turek et al., 1976). aMT implants cause testicular regression in long-day intact. male Peromyscus leucopus ( Johnston et al., 1980; Lynch et al., 1976) but do not retard testicular regression on short days ( Petterborg et al., 1981). Also varied results have been observed on the effects of photoperiod and melatonin on gonadal function of prepubertal and adult animals of Microtus and Peromyscus species. Although in the case of F. pennanti silastic capsule implants of aMT and MT lead to testicular regression in both intact and Px animals, ( Saxena, 1988) the effects of this continuous mode of MI administration under different photoperiods remains to be assessed.

Majumder, A. Prey Selection, Food Habits and Population Structure of Sympatric Carnivores: Tiger Panthera tigris tigris (L.), Leopard Panthera pardus (L.) and Dhole Cuon alpinus (Pallas) in Pench Tiger Reserve, Madhya Pradesh (India) (Saurashtra University, Rajkot, 2011).