Zuzana Musilová

• Professor (Assistant) at Charles University in Prague

Cichlid visual systems can evolve rapidly during adaptive radiations. This study investigates the Bermin crater lake species flock in Cameroon, comprising thirteen (nine valid and four undescribed) Coptodon species, to explore the effects of deep-water light environments on visual evolution. We analyzed visual opsin genes and their expression using...

Haemoglobin is a key molecule for oxygen transport in vertebrates. It exhibits remarkable gene diversity in teleost fishes, reflecting adaptation to various aquatic environments. In this study, we present the dynamic evolution of haemoglobin subunit genes based on a comparison of high‐quality genome assemblies of 24 vertebrate species, including 17...

Multiple species of the elephant fishes (Mormyridae) commonly coexist in sympatry in most African tropical rivers and lakes. In this study, we investigated the trophic ecology and potential trophic niche partitioning of eleven mormyrid fish species from the Sanaga River system in Cameroon using the stable isotope composition of carbon and nitrogen...

Hemoglobin is a crucial element of the oxygen transport system in vertebrates. It exhibits remarkable gene diversity across teleost fishes, reflecting their evolutionary adaptations for thriving in various aquatic environments. In this study, we present the dynamic evolution of hemoglobin subunit genes based on a comparison of high quality long-rea...

The real-time quantitative PCR (qPCR) calibration curves are highly reproducible and allow the generation of specific, sensitive, and reproducible data that can be used for gene quantification. However, it is important to rigorously validate the external calibration curve model in qPCR since absolute quantification is dependent on the standards use...

Background Smell abilities differ greatly among vertebrate species due to distinct sensory needs, with exceptional variability reported in the number of olfactory genes and the size of the odour-processing regions of the brain. However, key environmental factors shaping genomic and phenotypic changes linked to the olfactory system remain difficult...

Elevated environmental levels of elements originating from anthropogenic activities threaten natural communities and public health, as these elements can persist and bioaccumulate in the environment. However, their environmental risks and bioaccumulation patterns are often habitat-, species- and element-specific. We studied the bioaccumulation patt...

Deposits of fly ash and other coal combustion wastes are common remnants of the energy industry. Despite their environmental risks from heavy metals and trace elements, they have been revealed as refuges for threatened terrestrial biodiversity. Surprisingly, freshwater biodiversity of fly ash sedimentation lagoons remains unknown despite such lack...

Multiple species of the elephant fishes (Mormyridae) commonly coexist in sympatry in most African tropical rivers and lakes. In this study, we investigated the trophic ecology and potential trophic niche partitioning of eleven mormyrid fish species from the Sanaga River system (Cameroon) using the stable isotopes of carbon and nitrogen of muscles a...

Vertebrates have four visual cone opsin classes that mediate sensitivity from ultraviolet to red wavelengths of light. The rhodopsin-like 2 (RH2) opsin is sensitive to the central mostly green part of the spectrum. While lost in some terrestrial vertebrates (mammals), the RH2 opsin gene has proliferated during the evolution of teleost fishes. Here,...

Although the concept of trophic interactions has been used for a long time, there are still considerable gaps in our understanding of the effect of various environmental factors on trophic interactions within river fish assemblages. Carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotope ratios of 20 species of fish belonging to both eurytopic and rheophi...

Length-weight relationships (LWRs) are useful for calculating weight based on measurements of length. Here we provide LWRs for 17 species of fish from the rivers Vltava and Elbe in the Czech Republic, Central Europe. The samples were collected by electrofishing from May 2016 to August 2019. There are far fewer LWRs for riverine than lotic fish. All...

Smell abilities differ greatly among vertebrate species, as reflected by the exceptional size variability of gene families and brain regions involved in odour detection. However, key environmental factors shaping the molecular and phenotypic evolution of the olfactory sensory system remain mostly unknown. Here, we investigate the association betwee...

Fish often change their habitat and trophic preferences during development. Dramatic functional differences between embryos, larvae, juveniles and adults also concern sensory systems, including vision. Here, we focus on the photoreceptors (rod and cone cells) in the retina and their gene expression profiles during development. Using comparative tra...

Globalisation has led to increased trade and consumption of fish worldwide. As international trade and consumption of fish increases, so does the likelihood of fish being adulterated. It is often an illegal exchange of species where a cheaper species is substituted for a more expensive and rarer one. In Europe, the anglerfish (Lophius piscatorius)...

The small cyprinid genus Prolabeops Schultz, 1941 is restricted to the Nyong and Sanaga River systems in Cameroon. In the past, the genus had been suggested to be either a member of the Labeoninae, Torinae or the Smiliogastrinae mainly on the basis of morphological similarities, and it is nowadays considered as incertae sedis within the Cypriniform...

African cichlids (subfamily: Pseudocrenilabrinae) are among the most diverse vertebrates, and their propensity for repeated rapid radiation has made them a celebrated model system in evolutionary research. Nonetheless, despite numerous studies, phylogenetic uncertainty persists, and riverine lineages remain comparatively underrepresented in higher-...

Fish often change their habitat and trophic preferences during development. Dramatic functional differences between embryos, larvae, juveniles and adults also concern sensory systems, including vision. Here we focus on the photoreceptors (rod and cone cells) in the retina and their gene expression profiles during the development. Using comparative...

The visual sensory system is essential for animals to perceive their environment and is thus under strong selection. In aquatic environments, light intensity and spectrum differ primarily along a depth gradient. Rhodopsin (RH1) is the only opsin responsible for dim‐light vision in vertebrates and has been shown to evolve in response to the respecti...

Cover page for an original article "Visual Gene Expression Reveals a Cone-to-Rod Developmental Progression in Deep-Sea Fishes" by Lupše et al. 2021. https://doi.org/10.1093/molbev/msab281. Illustration by Zuzana Musilova.

Vertebrates use cone cells in the retina for color vision and rod cells to see in dim light. Many deep-sea fishes have adapted to their environment to have only rod cells in the retina, while both rod and cone genes are still preserved in their genomes. As deep-sea fish larvae start their lives in the shallow, and only later submerge to the depth,...

Parvalbumin is considered a major fish allergen. Here, we report the molecular evolution of the parvalbumin genes in bony fishes based on 19 whole genomes and 70 transcriptomes. We found unexpectedly high parvalbumin diversity in teleosts; three main gene types (pvalb-α, pvalb-β1, and pvalb-β2, including oncomodulins) originated at the onset of ver...

Per- and polyfluorinated alkyl substances (PFASs) represent a group of highly recalcitrant micropollutants, that continuously endanger the environment. The present work describes the geographical trends of fish contamination by individual PFASs (including new compounds, e.g., Gen-X) assessed by analyzing the muscle tissues of 5 separate freshwater...

Visual opsin genes expressed in the rod and cone photoreceptor cells of the retina are core components of the visual sensory system of vertebrates. Here, we provide an overview of the dynamic evolution of visual opsin genes in the most species-rich group of vertebrates, teleost fishes. The examination of the rich genomic resources now available for...

Vertebrates generally use cone cells in retina for colour vision and rod cells to see in the dim light. Many deep-sea fishes have only rod cells in the retina, while both rod and cone genes are still preserved in their genomes. As deep-sea fish larvae start their lives in the shallow, well-lit epipelagic zone, they have to cope with diverse environ...

Vertebrates have four visual cone opsin classes that, together with a light-sensitive chromophore, provide sensitivity from the ultraviolet to the red wavelengths of light. The rhodopsin-like 2 (RH2) opsin is sensitive to the centre blue-green part of the spectrum, which is the most prevalent light underwater. While various vertebrate groups such a...

Photopigments, consisting of an opsin protein bound to a light-sensitive chromophore, are at the centre of vertebrate vision. The vertebrate ancestor already possessed four cone opsin classes involved in colour perception during bright-light conditions, which are sensitive from the ultraviolet to the red-wavelengths of light. Teleosts experienced a...

Southeast Asia is one of the world’s biodiversity hotspots, and the high level of diversity and endemism was reached by colonisation events as well as internal diversification. We investigate the phylogenetic relationships and biogeographic history of the loach genus Nemacheilus, which is widely distributed and common across freshwaters of Southeas...

Background: The invasive benthic round goby (Neogobius melanostomus) is the most successful temperate invasive fish and has spread in aquatic ecosystems on both sides of the Atlantic. Invasive species constitute powerful in situ experimental systems to study fast adaptation and directional selection on short ecological timescales and present promi...

Background Cichlids are a prime model system in evolutionary research and several of the most prominent examples of adaptive radiations are found in the East African Lakes Tanganyika, Malawi and Victoria, all part of the East African cichlid radiation (EAR). In the past, great effort has been invested in reconstructing the evolutionary and biogeogr...

Cichlid fishes are the subject of scientific interest because of their rapid adaptive radiation, resulting in extensive ecological and taxonomic diversity. In this study, we examined 11 morphologically distinct cichlid species endemic to Barombi Mbo, the largest crater lake in western Cameroon, namely Konia eisentrauti, Konia dikume, Myaka myaka, P...

Cichlid fishes have as many as seven different cone opsin genes (SWS1, SWS2B, SWS2A, RH2B, RH2Aβ, RH2Aα and LWS) in their genome responsible for colour vision. Each opsin protein is sensitive to different wavelengths (see Figure 1); however, only a subset of them are usually expressed as previously shown in lacustrine cichlids from lakes Victoria,...

In deep‐water animals, visual sensory system is often challenged by the dim‐light environment. Here, we focus on the molecular mechanisms involved in rapid deep‐water adaptations. We examine visual system evolution in a small‐scale yet phenotypically and ecologically diverse adaptive radiation, the species flock of cichlid fishes in deep crater lak...

Do some fish see color in the black-and-white world of the ocean's depths? In episode 55, Zuzana Musilová, an evolutionary biologist at Charles University in Prague, discusses her research into the unique way that some fish in the deep ocean’s darkness may be able to see in color. Her article "Vision using multiple distinct rod opsins in deep-sea f...

Fish catch color with rods Vertebrates are typically thought to have a consistent system for processing light, in which multiple cone opsins permit color vision during the day, but a single rod opsin provides only monochrome vision in the dark. Musilova et al. analyzed more than 100 deep-sea fish genomes and found a previously unknown proliferatio...

Sensory adaptation is essential for animal survival and reproduction. As species are constantly challenged by their environment (e.g. predator-prey interactions, reproduction, finding food), their sensory systems are very diverse and highly micro-habitat specific, thus enabling the direct detection of environmental conditions and changes in the sur...

Vertebrate vision is accomplished through a set of light-sensitive photopigments, which are located in the photoreceptors of the retina and consist of a visual opsin protein bound to a chromophore. In dim-light, vertebrates generally rely upon a single rod opsin (RH1) for obtaining visual information. By inspecting 101 fish genomes, we found that t...

Ecoevolutionary dynamics of the gut microbiota at the macroscale level, that is, in across-species comparisons, are largely driven by ecological variables and host genotype. The repeated explosive radiations of African cichlid fishes in distinct lakes, following a dietary diversification in a context of reduced genetic diversity, provide a natural...

Unnoticed by the public, initiatives for oil exploration are advanced in Africa’s largest freshwater reservoirs, including Lakes Tanganyika, Malawi and lately Albert, threatening their ecosystems and biota. It is imperative that environmental impact assessments are conducted by independent organizations to ensure that decisions on this matter are b...

As the world’s demands for hydrocarbons increase, remote areas previously made inaccessible by technological limitations are now being prospected for oil and gas deposits. Virtually unnoticed by the public, such activities are ongoing in the East African Great Lakes region, threatening these ecosystems famed for their hyper-diverse biota, includin...

Background Understanding the genetic basis of novel traits is a central topic in evolutionary biology. Two novel pigmentation phenotypes, egg-spots and blotches, emerged during the rapid diversification of East African cichlid fishes. Egg-spots are circular pigmentation markings on the anal fins of hundreds of derived haplochromine cichlids species...

Background Understanding the genetic basis of novel traits is a central topic in evolutionary biology. Two novel pigmentation phenotypes, egg-spots and blotches, emerged during the rapid diversification of East African cichlid fishes. Egg-spots are circular pigmentation markings on the anal fins of hundreds of derived haplochromine cichlids species...

Divergence-time estimation based on molecular phylogenies and the fossil record has provided insights into fundamental questions of evolutionary biology. In Bayesian node dating, phylogenies are commonly time calibrated through the specification of calibration densities on nodes representing clades with known fossil occurrences. Unfortunately, the...

Animals often change their habitat throughout ontogeny; yet, the triggers for habitat transitions and how these correlate with developmental changes - e.g. physiological, morphological, and behavioural - remain largely unknown. Here, we investigated how ontogenetic changes in body colouration and of the visual system relate to habitat transitions i...

Divergence-time estimation based on molecular phylogenies and the fossil record has provided insights into fundamental questions of evolutionary biology. In Bayesian node dating, phylogenies are commonly time calibrated through the specification of calibration densities on nodes representing clades with known fossil occurrences. Unfortunately, the...

We reconstruct the historical biogeography of cichlid fishes endemic to the trans-Andean region of NW South America. DNA sequences were used to study historical biogeography of the cichlid genera Andinoacara (Cichlasomatini) and Mesoheros (Heroini). Two event-based methodological approaches, parsimony-based Statistical Dispersal-Vicariance Analysis...

We sequenced the complete mitochondrial genome of the Madagascar ground gecko Paroedura picta (Squamata: Gekkonidae). The mitogenome is 17 220 base pairs long and conforms to the typical vertebrate gene composition and arrangement, i.e. 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes and 1919 bp long control region. We reconstructed p...

Significance Gene and whole-genome duplications are important evolutionary forces promoting organismal diversification. Teleost fishes, for example, possess many gene duplicates responsible for photoreception (opsins), which emerged through gene duplication and allow fishes to adapt to the various light conditions of the aquatic environment. Here,...

The extinction of Stomatepia mongo Trewavas, 1972, a cichlid species from the Barombi Mbo crater lake, Cameroon, has been repeatedly speculated. Here, we review over 180 presumably unpublished records of this species since its description. Because a majority of them originate from our extensive surveys in the last several years, it is evident that...

Background Annual Nothobranchius fish are distributed in East and Southern Africa and inhabit ephemeral pools filled during the monsoon season. Nothobranchius show extreme life-history adaptations: embryos survive by entering diapause and they are the vertebrates with the fastest maturation and the shortest lifespan. The distribution area of Nothob...

A comparative cytogenetic analysis was carried out in five species of a monophyletic clade of neotropical Cichlasomatine cichlids, namely Cleithracara maronii Steindachner, 1881, Ivanacara adoketa (Kullander et Prada-Pedreros, 1993), Nannacara anomala Regan, 1905, N. aureocephalus Allgayer, 1983 and N. taenia Regan, 1912. Karyotypes and other chrom...

Distinguishing between hybrid introgression and incomplete lineage sorting causing incongruence among gene trees in that they exhibit topological differences requires application of statistical approaches that are based on biologically relevant models. Such study is especially challenging in hybrid systems, where usual vectors mediating interspecif...

Hansen et al. (Reports, 15 November 2013, p. 850) published a high-resolution global forest map with detailed information on local forest loss and gain. We show that their product does not distinguish tropical forests from plantations and even herbaceous crops, which leads to a substantial underestimate of forest loss and compromises its value for...

The headwaters of five large African river basins flow through the Bié Plateau in Angola and still remain faunistically largely unexplored. We investigated fish fauna from the Cuanza and Okavango-Zambezi river systems from central Angola. We reconstructed molecular phylogenies of the most common cichlid species from the region, Tilapia sparrmanii a...

Selected specimens of cichlid fishes analyzed in the study. SL = standard length. A-C) Serranochromis macrocephalus and Tilapia sparrmanii showing evidence of faunal contacts between the Cuanza and Okavango river systems in central Angola. D-F) Other members of serranochromines sensu lato used for larger phylogenetic analysis. Please note that the...

Here we report first documented record of African pike (Hepsetus odoe) in the River Kukemá (upper Kwanza River Basin) from province Bié, Angola.

Andinoacara stalsbergi sp. n. is described from the drainages of trans-andean rivers and lakes at the Peruvian Pacifi c coast where this species occurs between Río Chira (Depto. Piura) in the north and Río Pisco (Depto. Ica) in the south. It is distinguished from its sister species A. rivulatus by the possession of a conspicuous white margin of bot...

Phylogenetic relationships among cichlasomatine cichlids were studied using an extensive taxon sampling and both morphological and molecular data sets. A new genus, Andinoacara n. gen. with six species (A. pulcher-rivulatus group of previous authors) from trans-andean South America and NW cis-andean South America, is described based on results of p...

Project background and objectives The magnitude and geographic reach of human impact on Earth’s biosphere has increased rapidly over the last 100 years, in particular in equatorial East Africa where rates of population growth and the intensification of agriculture are among the highest in the world, and where developing economies strongly depend on...

We have conducted the first comprehensive molecular phylogeny of the tribe Cichlasomatini including all valid genera as well as important species of questionable generic status. To recover the relationships among cichlasomatine genera and to test their monophyly we analyzed sequences from two mitochondrial (16S rRNA, cytochrome b) and one nuclear m...

We present a developmental study focusing on the development of coloration patterns in a subgroup of Neotropical cichlids, the subfamily Cichlasomatinae. Based on the presented coloration ontogenetic series of 40 species we show that developmental information is a necessary prerequisite for any serious attempts in understanding adult coloration pat...