Geographic variation in body size and sexual dimorphism of the short‐nosed fruit bat (Cynopterus sphinx) was investigated in peninsular India. Bats were sampled at 12 localities along a 1200 km latitudinal transect that paralleled the eastern flanks of the Western Ghats. The geographic pattern of variation in external morphology of C. sphinx conforms to the predictions of Bergmann's Rule, as indicated by a steep, monotonic cline of increasing body size from south to north. This study represents one of the first conclusively documented examples of Bergmann's Rule in a tropical mammal and confirms that latitudinal clines in body size are not exclusively restricted to temperate zone homeotherms. Body size was indexed by a multivariate axis derived from principal components analysis of linear measurements that summarize body and wing dimensions. Additionally, length of forearm was used as a univariate index of structural size to examine geographic variation in a more inclusive sample of bats across the latitudinal transect. Multivariate and univariate size metrics were strongly and positively correlated with body mass, and exhibited highly concordant patterns of clinal variation. Stepwise multiple regression on climatological variables revealed that increasing size of male and female C. sphinx was associated with decreasing minimum temperature, increasing relative humidity, and increasing seasonality. Although patterns of geographic size variation were highly concordant between the sexes, C. sphinx also exhibited a latitudinal cline in the magnitude and direction of sexual size dimorphism. The size differential reversed direction across the latitudinal gradient, as males averaged larger in the north, and females averaged larger in the south. The degree of female‐biased size dimorphism across the transect was negatively correlated with body size of both sexes. Canonical discriminant analysis revealed that male‐ and female‐biased size dimorphism were based on contrasting sets of external characters. Available data on geographic variation in the degree of polygyny in C. sphinx suggests that sexual selection on male size may play a role in determining the geographic pattern of sexual size dimorphism.

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Fishes are the most successful and diverse group of vertebrate animals, first appeared during Devonian period. Despite of certain differences, the immune system of fish is physiologically similar to that of higher vertebrates. The heterogenous group of fishes are the apparent link between innate immunity and the first appearance of the adaptive immune response. Importantly, fishes have immune organs homologous to that of mammalian immune system. In comparison to higher vertebrates, fishes live free in their environment from the early embryonic stage and during that time mostly they are dependent on non-specific immune system for their survival. In the fishes, non-specific immunity is the fundamental defense mechanism, therewith acquired immunity also plays key role in maintaining homeostasis by activation though a system of receptors proteins, which identify pathogen associated molecular pattern typical of pathogenic microorganism includes lipopolysaccharides, peptidoglycans, DNA, RNA and other molecules that are typically not present on the surface of multicellular organism. There are several external factors like environmental factors, biological factors, stress and internal factors like genetic makeup, age and sex, maternal effect etc. can affect immunological defense capabilities of the fishes.

We used radiotelemetry to evaluate relationships between female Cynopterus sphinx and their young during the late lactation and weaning periods. Our observations suggest that young C. sphinx may be tutored by their mothers during this period. Before young are weaned, females intermittently visit their young during nightly feeding bouts. During the weaning period, mothers forage near their day roosts and are accompanied by or forage near their young. We suggest that observational learning during the late lactation and weaning period occurs when young C. sphinx accompany their mothers on foraging flights. Thus, young bats may have an opportunity to learn the location of profitable food patches.

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This paper presents a novel scheme that provides high level of security and privacy in a Wireless Mesh Network (WMN). We combine an approach of Network Coding with multiple layered encryption of onion routing for a WMN. An added superior feature provides higher level of security and privacy. Sensitive network information is confined to 1-hop neighborhood which is available anyways in a wireless medium with nodes using a bivariate polynomial. The only routing information divulged to a relay node is about next hop. No plain text is ever transmitted and all data can only be decrypted by its source and destination.Prior work finds it difficult to enforce encryption with network coding without divulging in complete routing information,hence losing privacy and anonymity. We compare our scheme with other existing approach for several networks. The preliminary results show this work to provide superior security and anonymity at low overhead cost.

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The issues related to network data security were identified shortly after the inception of the first wired network. Initial protocols relied heavily on obscurity as the main tool for security provisions. Hacking into a wired network requires physically tapping into the wire link on which the data is being transferred. Both these factors seemed to work hand in hand and made secured communication somewhat possible using simple protocols. Then came the wireless network which radically changed the field and associated environment. How do you secure something that freely travels through the air as a medium? Furthermore, wireless technology empowered devices to be mobile, making it harder for security protocols to identify and locate a malicious device in the network while making it easier for hackers to access different parts of the network while moving around. Quite often, the discussion centered on the question: Is it even possible to provide complete security in a wireless network? It can be debated that wireless networks and perfect data security are mutually exclusive. Availability of latest wideband wireless technologies have diminished predominantly large gap between the network capacities of a wireless network versus a wired one. Regardless, the physical medium limitation still exists for a wired network. Hence, security is a way more complicated and harder goal to achieve for a wireless network (Imai, Rahman, & Kobara, 2006). So, it can be safely assumed that a security protocol that is robust for a wireless network will provide at least equal if not better level of security in a similar wired network. Henceforth, we will talk about security essentially in a wireless network and readers should assume it to be equally applicable to a wired network.