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Rapid effects of marine reserves via larval dispersal

Richard Cudney Bueno (2009, [Artículo])

Marine reserves have been advocated worldwide as conservation and fishery management tools. It is argued that they can protect ecosystems and also benefit fisheries via density-dependent spillover of adults and enhanced larval dispersal into fishing areas. However, while evidence has shown that marine reserves can meet conservation targets, their effects on fisheries are less understood. In particular, the basic question of if and over what temporal and spatial scales reserves can benefit fished populations via larval dispersal remains unanswered. We tested predictions of a larval transport model for a marine reserve network in the Gulf of California, Mexico, via field oceanography and repeated density counts of recently settled juvenile commercial mollusks before and after reserve establishment. We show that local retention of larvae within a reserve network can take place with enhanced, but spatially-explicit, recruitment to local fisheries. Enhancement occurred rapidly (2 yrs), with up to a three-fold increase in density of juveniles found in fished areas at the downstream edge of the reserve network, but other fishing areas within the network were unaffected. These findings were consistent with our model predictions. Our findings underscore the potential benefits of protecting larval sources and show that enhancement in recruitment can be manifested rapidly. However, benefits can be markedly variable within a local seascape. Hence, effects of marine reserve networks, positive or negative, may be overlooked when only focusing on overall responses and not considering finer spatially-explicit responses within a reserve network and its adjacent fishing grounds. Our results therefore call for future research on marine reserves that addresses this variability in order to help frame appropriate scenarios for the spatial management scales of interest. © 2009 Cudney-Bueno et al.

article, environmental monitoring, fishery, larva, marine environment, marine species, Mexico, mollusc, nonhuman, oceanography, prediction, animal, biology, environmental protection, food industry, geography, growth, development and aging, larva, met CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Octopus maya white body show sex-specific transcriptomic profiles during the reproductive phase, with high differentiation in signaling pathways

Oscar Juárez (2019, [Artículo])

White bodies (WB), multilobulated soft tissue that wraps the optic tracts and optic lobes, have been considered the hematopoietic organ of the cephalopods. Its glandular appearance and its lobular morphology suggest that different parts of the WB may perform different functions, but a detailed functional analysis of the octopus WB is lacking. The aim of this study is to describe the transcriptomic profile of WB to better understand its functions, with emphasis on the difference between sexes during reproductive events. Then, validation via qPCR was performed using different tissues to find out tissue-specific transcripts. High differentiation in signaling pathways was observed in the comparison of female and male transcriptomic profiles. For instance, the expression of genes involved in the androgen receptor-signaling pathway were detected only in males, whereas estrogen receptor showed higher expression in females. Highly expressed genes in males enriched oxidation-reduction and apoptotic processes, which are related to the immune response. On the other hand, expression of genes involved in replicative senescence and the response to cortisol were only detected in females. Moreover, the transcripts with higher expression in females enriched a wide variety of signaling pathways mediated by molecules like neuropeptides, integrins, MAPKs and receptors like TNF and Toll-like. In addition, these putative neuropeptide transcripts, showed higher expression in females’ WB and were not detected in other analyzed tissues. These results suggest that the differentiation in signaling pathways in white bodies of O. maya influences the physiological dimorphism between females and males during the reproductive phase. © 2019 Juárez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

androgen receptor, integrin, mitogen activated protein kinase, neuropeptide, transcriptome, tumor necrosis factor, argonaute protein, corticotropin releasing factor receptor, corticotropin releasing factor receptor 2, DEAD box protein, estradiol 17be BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) BIOLOGÍA ANIMAL (ZOOLOGÍA)

Dos obituarios

VICENTE FRANCISCO TORRES MEDINA (2020, [Artículo])

Artículo número 4 de la Sección Variaciones. 12 páginas. tyvlliv

En estos tiempos de coronavirus, la muerte no respeta a los escritores. Luis Sepúlveda fue una de las víctimas. La entrevista que entrego quiere ser una suerte de homenaje, o despedida. También proporciona información de la que sólo circula en los centros de estudios literarios. George Steiner, sabio magnífico, se fue sobre las dulces aguas de la edad. De él ofrezco el recuerdo de algunos de sus libros.

In these times of coronavirus, death does not respect writers. Luis Sepúlveda was one of the victims. The interview that I give wants to be a kind of tribute, or farewell. It also provides information that only circulates in literary study centers. George Steiner, magnificent sage, went on the sweet waters of age. Of him I offer the memory of some of his books.

Telurismo, amazonia, ecologismo, crítica literaria, canon literario. Tellurism, Amazon, environmentalism, literary criticism, literary canon. HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA LITERARIAS