Publications by authors named "Jonathan Ready"

The commercial importance of cephalopods has increased considerably, being an important fishing resource. However, during the preparation for commercialization of those species, they suffer the process known as "finning" which includes removing and separating the head, arm, skin or even having the body structure cut into rings, which ends up making it difficult or often prevents the identification of the species, which can lead to replacements. In this sense, the present study aimed to use the large ribosomal region, rrnL (16S rDNA) to genetically identify cephalopod species sold in markets and fairs in Latin America.

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Knowledge on species composition is the first step necessary for the proper conservation and management of biological resources and ecologically relevant species. High species diversity and a lack of diagnostic characters for some groups can impose difficulties for taxonomic identification through traditional methodologies, and ichthyoplankton (fish larvae and eggs) are a good example of such a scenario. With more than 35.

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Sex chromosomes are evolutionarily labile in many animals and sometimes fuse with autosomes, creating so-called neo-sex chromosomes. Fusions between sex chromosomes and autosomes have been proposed to reduce sexual conflict and to promote adaptation and reproductive isolation among species. Recently, advances in genomics have fuelled the discovery of such fusions across the tree of life.

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Article Synopsis
  • Effective biomonitoring strategies are essential to protect vulnerable aquatic habitats from human-induced ecosystem changes, particularly in marine environments affected by climate change.
  • This study focuses on the Oslo fjord, utilizing eDNA-based monitoring over a year to analyze aquatic biodiversity and identify 63 fish species, revealing significant migratory patterns and seasonal dynamics.
  • eDNA metabarcoding proves to be a cost-effective and powerful method for assessing fish communities, offering valuable data for conservation efforts and management strategies in fluctuating marine ecosystems.
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Article Synopsis
  • Hybridization can facilitate the sharing of adaptations between different lineages and may lead to the emergence of new species, although clear cases of this phenomenon are uncommon.
  • In a study of Heliconius butterflies, researchers found that Heliconius elevatus, a hybrid species, has independently evolved for over 180,000 years alongside its parent species, despite ongoing genetic mixing with one parent.
  • The study highlighted that specific traits related to survival and reproduction, which were influenced by genetic contributions from both parent species, enabled H. elevatus to thrive in the same environment as its parents, demonstrating that speciation can occur even with gene flow in a complex genetic landscape.
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Bryconops Kner, 1858, includes two well defined subgenera based on morphological evidence, with each containing at least one species (B. (Bryconops) caudomaculatus and B. (Creatochanes) melanurus) with a very wide distribution, within which regional populations present color variations.

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Carangid fishes are commercially important in fisheries and aquaculture. They are distributed worldwide in both tropical and subtropical marine ecosystems. Their role in food webs is often unclear since their diet cannot be easily identified by traditional gut content analysis.

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The coastline of Sub-Saharan Africa hosts highly diverse fish communities of great conservation value, which are also key resources for local livelihoods. However, many costal ecosystems are threatened by overexploitation and their conservation state is frequently unknown due to their vast spatial extent and limited monitoring budgets. Here, we evaluated the potential of citizen science-based eDNA surveys to alleviate such chronic data deficiencies and assessed fish communities in Mozambique using two 12S metabarcoding primer sets.

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Identifying the relative importance of different mechanisms responsible for the emergence and maintenance of phenotypic diversity can be challenging, as multiple selective pressures and stochastic events are involved in these processes. Therefore, testing how environmental conditions shape the distribution of phenotypes can offer important insights on local adaptation, divergence, and speciation. The red-yellow Müllerian mimicry ring of butterflies exhibits a wide diversity of color patterns across the Neotropics and is involved in multiple hybrid zones, making it a powerful system to investigate environmental drivers of phenotypic distributions.

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The biogeography of American loliginid squids has been improved in recent years, but certain key taxa have been missing. Given that the most accurate phylogenies and estimates of divergence times of common ancestors depend heavily on good taxonomic coverage we have reanalyzed the genus Lolliguncula in light of new samples that increase the geographic and taxonomic coverage. New sequences were produced using standard methods to update an existing dataset for COI, 16S and Rhodopsin markers.

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In many animals, mate choice is important for the maintenance of reproductive isolation between species. Traits important for mate choice and behavioral isolation are predicted to be under strong stabilizing selection within species; however, such traits can also exhibit variation at the population level driven by neutral and adaptive evolutionary processes. Here, we describe patterns of divergence among androconial and genital chemical profiles at inter- and intraspecific levels in mimetic butterflies.

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Is there only one electric eel species? For two and a half centuries since its description by Linnaeus, Electrophorus electricus has captivated humankind by its capacity to generate strong electric discharges. Despite the importance of Electrophorus in multiple fields of science, the possibility of additional species-level diversity in the genus, which could also reveal a hidden variety of substances and bioelectrogenic functions, has hitherto not been explored. Here, based on overwhelming patterns of genetic, morphological, and ecological data, we reject the hypothesis of a single species broadly distributed throughout Greater Amazonia.

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(Cichliformes, Cichlidae) present a highly conserved diploid number 2n=48 with fundamental numbers varying between 52 and 62. We analyzed four species in order to investigate the role of repetitive DNA in chromosome evolution in the genus. , cf.

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The cephalopod fauna of the southwestern Atlantic is especially poorly-known because sampling is mostly limited to commercial net-fishing operations that are relatively inefficient at obtaining cephalopods associated with complex benthic substrates. Cephalopods have been identified in the diets of many large marine species but, as few hard structures survive digestion in most cases, the identification of ingested specimens to species level is often impossible. Samples can be identified by molecular techniques like barcoding and for cephalopods, mitochondrial 16S and COI genes have proven to be useful diagnostic markers for this purpose.

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Chromosome changes can perform an important role in speciation by acting as post-zygotic reproductive barriers. The Neotropical electric fish genus (Gymnotiformes, Hypopomidae) has 28 described species, but cytogenetic data are hitherto available only for four of them. To understand karyotype evolution and investigate the possible role of chromosome changes in the diversification of this genus, we describe here the karyotype of eight species of from a sympatric assemblage in the central Amazon basin.

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Various species and lineages that until recently were identified as Microsternarchus bilineatus (Hypopomidae, Gymnotiformes) have a widespread distribution in the Amazon and Orinoco River basins and across the Guiana shield. Recent molecular studies show five distinct lineages for Microsternarchus from different localities. These results suggest that this previously monotypic genus actually consists of more than one species.

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Although recent years have seen an increase in genetic analyses that identify new species of cephalopods and phylogeographic patterns, the loliginid squid of South America remain one of the least studied groups. The suggestion that Doryteuthis plei may represent distinct lineages within its extensive distribution along the western Atlantic coasts from Cape Hatteras, USA (36°N) to northern Argentina (35°S) is consistent with significant variation in a number of environmental variables along this range including in both temperature and salinity. In the present study D.

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The diversity of Hypancistrus species in the Xingu River is remarkable and the variation in color morphs represents a real challenge to taxonomists to delimit species boundaries. One of the most recognizable Hypancistrus complexes is the worm-lined species, known in the aquarium trade as King Tiger Plec in English, Hypancistrus "pão" in Portuguese or under the L-numbers L066 and L333 that represent two melanic pigment pattern phenotypes. To assess the identity of these two phenotypes, we described their karyotypes and sequenced part of the mitochondrial cytochrome oxidase I gene (DNA barcode).

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Mimesis is a relatively widespread phenomenon among reef fish, but the ontogenetic processes relevant for mimetic associations in fish are still poorly understood. In the present study, the allometric growth of two allopatric leaf-mimetic species of ephippid fishes, Chaetodipterus faber from the Atlantic and Platax orbicularis from the Indo-Pacific, was analyzed using ten morphological variables. The development of fins was considered owing to the importance of these structures for mimetic behaviors during early life stages.

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The electric eel, Electrophorus electricus, the only species of its genus, has a wide distribution in the Amazon and Orinoco drainages. There is little previous information regarding the population variation in E. electricus, with only basic karyotype data from two populations (Amazon and Araguaia Rivers).

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Squid of the genus Lolliguncula Steenstrup, 1881 are small bodied, coastal species capable of tolerating low salinity. Lolliguncula sp. are found exclusively in the New World, although only one of the four recognized species (Lolliguncula brevis) occurs in the Atlantic Ocean.

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The family Loliginidae Lesueur, 1821, is currently considered to include seven genera and approximately 50 species of neritic and coastal squids. These commercially important species occur in tropical and temperate coastal waters around the world. The taxonomy of the family has been revised a number of times in recent years, focusing in particular on genera such as Doryteuthis, Sepioteuthis, Alloteuthis, and Uroteuthis, which are represented by populations in the New World, Oceania, Europe/Africa, and Asia.

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Quantifying the spatial distribution of taxa is an important prerequisite for the preservation of biodiversity, and can provide a baseline against which to measure the impacts of climate change. Here we analyse patterns of marine mammal species richness based on predictions of global distributional ranges for 115 species, including all extant pinnipeds and cetaceans. We used an environmental suitability model specifically designed to address the paucity of distributional data for many marine mammal species.

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