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The survival of a species largely depends on the ability of individuals to reproduce, thus perpetuating their life history. The advent of metazoans (i.e. pluricellular animals) brought about the evolution of specialized tissues and organs, which in turn led to the development of complex protein regulatory pathways. This study sought to elucidate the evolutionary relationships between female reproduction-associated proteins by analyzing the transcriptomes of representative species from a selection of marine invertebrate phyla. Our study identified more than 50 reproduction-related genes across a wide evolutionary spectrum, from Porifera to Vertebrata. Among these, a total of 19 sequences had not been previously reported in at least one phylum, particularly in Porifera. Moreover, most of the structural differences between these proteins did not appear to be determined by environmental pressures or reproductive strategies, but largely obeyed a distinguishable evolutionary pattern from sponges to mammals.

Salton Sea (a destination resort) is to be saved from being converted into a skeleton-filled wasteland. The critical amount of water flowing into the sea to maintain its level and salinity has been diverted since January 2018. This will lead to shrinking volumes and increasing salinities. Ecological consequences and public health impacts of altered conditions will be phenomenal. We design and analyze a minimal eco-epidemiological model to figure out future journey of this sea; a way station for fish-eating migratory birds. The mathematical model has been assembled in terms of prey-predator interaction. The salient feature of the proposed model is its seasonally varying contact rate which represents rate of conversion of susceptible fishes into infectives. We have analytically investigated the global stability, disease persistence and periodic solutions of the proposed model system. Susceptible prey-induced periodic solution is globally asymptotically stable when ${\bar{R}}_{01}<1$, otherwise unstable and hence disease persists for ${\bar{R}}_{01}>1$.

Global stability and Hopf bifurcation (HB) analysis help us extract parameter values to explore the dynamical behavior of the model system. Two-dimensional parameter scans and bifurcation diagrams reveal that the model displays propensity towards chaotic dynamics, which is associated with extinction-sized population densities. In the presence of stochastic external forces, this implies extinction of most of the fish species. This, in turn, suggests that resident birds will have to migrate to other destinations. The fish-eating migratory birds will be forced to switch over to invertebrates. Ecological consequences and public health impacts of this transition would be severe. Conservation groups are solicited to draw attention of the government to avert this impounding danger. It is important to plan for an ecosystem-wide transition such that impacts on birds and on human inhabitants living adjacent to the shrinking and salinizing sea are minimized.

Understanding the extent and causes of insect diversity in the humid tropics is one of the major challenges in modern ecology. We review some of the current approaches to this problem, and discuss how future progress may be made. Recent calculations that there may be more than 30 million species of insect on earth have focused attention on the magnitude of this problem and stimulated several new lines of research (although the true figure is now widely thought to be between five and ten million species). We discuss work based on insecticidal fogging surveys; studies of herbivore and parasitoid specificity; macroecological approaches; and the construction of food webs. It is argued that progress in estimating insect diversity and in understanding insect community dynamics will be enhanced by building local inventories of species diversity, and in descriptive and experimental studies of the trophic structure of communities. As an illustration of work aimed at the last goal, we discuss the construction and analysis of quantitative host-parasitoid food webs, drawing on our work on leaf miner communities in Central America.

Lipid mediator is the collective term for prostanoids, leukotrienes, lysophospholipids, platelet-activating factor, endocannabinoids and other bioactive lipids, that are involved in various physiological functions including inflammation, immune regulation and cellular development. They act by binding to their ligand-specific G-protein coupled receptors (GPCRs). Since 1990's a number of lipid GPCRs have been cloned in humans, with a few more identified in other vertebrates. However, the conservation of these receptors has been poorly investigated in other eukaryotes. Herein we performed a phylogenetic analysis by collecting their orthologs in 13 eukaryotes with complete genomes. The analysis shows that orthologs for prostanoid receptors are likely to be conserved in the 13 eukaryotes. In contrast, those for lysophospholipid and cannabinoid receptors appear to be conserved only in vertebrates and chordates. Receptors for leukotrienes and other bioactive lipids are limited to vertebrates. These results indicate that the lipid mediators and their receptors have coevolved with the development of highly modulated physiological functions such as immune regulation and the formation of the central nervous system. Accordingly, examining the presence and role of lipid mediator GPCR orthologs in invertebrate species can provide insight into the development of fundamental biological processes across diverse taxa.