Gabriele Uhl

University of Greifswald · Zoological Institut and Museum

In the internet era, the digital architecture that keeps us connected and informed may also amplify the spread of misinformation. This problem is gaining global attention, as evidence accumulates that misinformation may interfere with democratic processes and undermine collective responses to environmental and health crises. In an increasingly poll...

Differences between sexes in growth, ecology and behaviour strongly shape species biology. In some animal groups, such as spiders, it is difficult or impossible to identify the sex of juveniles based on external morphology. This information would be useful for field surveys, behavioural experiments and ecological studies, such as those on sex ratio...

Mass media plays an important role in the construction and circulation of risk perception associated with animals. Widely feared groups such as spiders frequently end up in the spotlight of traditional and social media. We compiled an expert-curated global database on the online newspaper coverage of human-spider encounters over the past ten years...

In the Internet era, the digital architecture that keeps us connected and informed may collaterally amplify the spread of misinformation and falsehood1,2. The magnitude of this problem is gaining global relevance3, as evidence accumulates that misinformation interferes with democratic processes and undermines collective responses to environmental a...

Sperm competition drives traits that enhance fertilization success. The amount of sperm transferred relative to competitors is key for attaining paternity. Female reproductive morphology and male mating order may also influence fertilization, however the outcome for sperm precedence under intense sperm competition remains poorly understood. In the...

Sexual selection has been shown to drive speciation. In dwarf spiders (erigonines), males possess diverse, sexually selected prosomal structures with nuptial-gift-producing glands. The genus Oedothorax is suitable for investigating the evolution of these features due to high structural variation. We have re-delimited this genus based on a phylogene...

Sexual selection has been shown to drive speciation. In dwarf spiders (erigonines), males possess diverse, sexually selected prosomal structures with nuptial-gift-producing glands. The genus Oedothorax is suitable for investigating the evolution of these features due to high structural variation. We have re-delimited this genus based on a phylogene...

Anthropogenic climate change is rapidly altering ecosystems, driving range shifts, range contractions, dwindling population sizes and local extinctions in many species. Some species, however, are expanding their ranges and seem to benefit from warming temperatures. This is the case for the wasp spider, Argiope bruennichi, which has undergone a rang...

Differences between sexes in growth, ecology and behavior strongly shape species biology. In some animal groups, such as spiders, it is difficult or impossible to identify the sex of juveniles. This information would be useful for field surveys, behavioral experiments, and ecological studies on e.g. sex ratios and dispersal. In species with sex chr...

Chemical communication plays a fundamental role in many aspects of an animal's life from assessing habitat quality to finding mating partners. Behavioural observations show that chemical communication likewise plays an important role in spiders, but the contexts and the substances involved are little explored. Here, we investigate the chemical comm...

Background Sexual selection has been considered to promote diversification and speciation. Sexually dimorphic species have been used to explore the supposed effect, however, with mixed results. In dwarf spiders (Erigoninae), many species are sexually dimorphic—males possess marked prosomal modifications. These male traits vary from moderate elevati...

Do animals set the course for the evolution of their lineage when manipulating their environment? This heavily disputed question is empirically unexplored but critical to interpret phenotypic diversity. Here, we tested whether the macroevolutionary rates of body morphology correlate with the use of built artifacts in a megadiverse clade comprising...

Background Sexual selection has been considered to promote diversification and speciation. Sexually dimorphic species have been used to explore the supposed effect, however, with mixed results. In dwarf spiders (Erigoninae), many species are sexually dimorphic - males possess marked prosomal modifications. These male traits vary from moderate eleva...

Sexual dimorphism can evolve under sexual selection or ecological factors. Sexually dimorphic male prosomal modifications are associated with gustatorial courtship in erigonines. The modifications vary from moderate elevations to bizarre shapes. Males transfer substances from these structures to females, which affect mate acceptance and fecundity....

Background Mating generally occurs after individuals reach adulthood. In many arthropods including spiders, the adult stage is marked by a final moult after which the genitalia are fully developed and functional. In several widow spider species (genus Latrodectus), however, immature females may mate a few days before they moult to adulthood, i.e. i...

Background Argiope bruennichi, the European wasp spider, has been investigated intensively as a focal species for studies on sexual selection, chemical communication, and the dynamics of rapid range expansion at a behavioral and genetic level. However, the lack of a reference genome has limited insights into the genetic basis for these phenomena. T...

Much of our knowledge regarding the role of chemicals in species recognition in arthropods is based on a few taxonomic groups, predominantly insect pest species. To investigate the chemical underpinnings of species recognition cues in other arthropods, we conducted mate choice experiments and analyzed the chemical profiles of two species in the lon...

Male mate choice likely occurs when costs are associated with courtship or mating. For example, when males produce continuous vibrational signals, provide nutritious nuptial gifts, or are likely killed during mating, they should assess female developmental and reproductive state. Substrate‐borne vibratory courtship signals are very common in spider...

Aggressive and cannibalistic female spiders can impose strong selection on male mating and fertilization strategies. Furthermore, the distinctive reproductive morphology of spiders is predicted to influence the outcome of sperm competition. Polyandry is common in spiders, leading to defensive male strategies that include guarding, plugging and self...

In animals that regularly experience tissue loss, physiological responses may have evolved to overcome the related costs. Changes in oxidative status may reflect such self-maintenance mechanisms. Here, we investigated how markers of oxidative status vary in female orb-weaving spiders (Larinia jeskovi) by mimicking two distinct types of tissue loss...

Condition-dependent secondary sexual traits and signals are often crucial for mate choice decisions. Nuptial gifts, provided by the male to the female during mating, may represent an indicator of male condition, especially if production of the gift is energetically costly. Additionally, other signalling modalities may well play a role in mate choic...

While chemical communication has been investigated intensively in vertebrates and insects, relatively little is known about the sensory world of spiders despite the fact that chemical cues play a key role in natural and sexual selection in this group. In insects, olfaction is performed with wall-pore and gustation with tip-pore sensilla. Since spid...

A main goal of ecological and evolutionary biology is understanding and predicting interactions between populations and both abiotic and biotic environments, the spatial and temporal variation of these interactions, and the effects on population dynamics and performance. Trait-based approaches can help to model these interactions and generate a com...

One of the strongest determinants of behavioural variation is the tradeoff between resource gain and safety. Although classical theory predicts optimal foraging under risk, empirical studies report large unexplained variation in behaviour. Intrinsic individual differences in risk‐taking behaviour might contribute to this variation. By repeatedly ex...

Assessing the genetic adaptive potential of populations and species is essential for better understanding evolutionary processes. However, the expression of genetic variation may depend on environmental conditions, which may speed up or slow down evolutionary responses. Thus, the same selection pressure may lead to different responses. Against this...

Background: Argiope bruennichi, the European wasp spider, has been studied intensively as to sexual selection, chemical communication, and the dynamics of rapid range expansion at a behavioral and genetic level. However, the lack of a reference genome has limited insights into the genetic basis for these phenomena. Therefore, we assembled a high-qu...

Sexual reproduction is pervasive in animals and has led to the evolution of sexual dimorphism. In most animals, males and females show marked differences in primary and secondary sexual traits. The formation of sex-specific organs and eventually sex-specific behaviors is defined during the development of an organism. Sex determination processes hav...

Some animals have evolved task differentiation among their eyes. A particular example is spiders, where most species have eight eyes, of which two (the principal eyes) are used for object discrimination, whereas the other three pairs (secondary eyes) detect movement. In the ctenid spider Cupiennius salei these two eye types correspond to two visual...

Keywords: brown widow spider Latrodectus geometricus male mate choice mating with subadults sexual cannibalism Mating generally occurs with adult females, which undergo a suite of changes in morphology, physiology and behaviour during maturation. In the brown widow spider, Latrodectus geometricus, however, males can mate with immature females durin...

Background: Dispersal and reproduction are key life-history traits that jointly determine species' potential to expand their distribution, for instance in light of ongoing climate change. These life-history traits are known to be under selection by changing local environmental conditions, but they may also evolve by spatial sorting. While local na...

Many ecological and evolutionary processes in animals depend upon microbial symbioses. In spiders, the role of the microbiome in these processes remains mostly unknown. We compared the microbiome between populations, individuals, and tissue types of a range-expanding spider, using 16S rRNA gene sequencing. Our study is one of the first to go beyond...

Some animals have evolved task differentiation among their eyes. A particular example is spiders, where most species have eight eyes, of which two (the principal eyes) are used for object discrimination, whereas the other three pairs (secondary eyes) detect movement. In the spider species Cupiennius salei these two eye types correspond to two visua...

In animals that regularly experience tissue loss, physiological responses may have evolved to overcome the related costs. Changes in oxidative status may reflect such self-maintenance mechanisms. Here, we investigated how markers of oxidative status varied in female orb-weaving spiders (Larinia jeskovi) by mimicking two distinct types of tissue los...

Background: Recognition is growing that many ecological and evolutionary processes in animals are dependent upon microbial symbioses. Although there is much known about the ecology and evolution of spiders, the role of the microbiome in these processes remains mostly unknown. We conducted an exploratory study of the microbiome of a range-expanding...

Background: Nervous tissue is an inherent component of the many specialized genital structures for transferring sperm directly into the female's body. However, the male copulatory organ of spiders was considered a puzzling exception. Based on the recent discovery of nervous tissue in the pedipalps of two distantly related spider species, we invest...

High throughput sequencing (HTS) has emerged as a valuable tool for the rapid isolation of genetic markers for population genetics and pedigree analysis. HTS-based SNP (single nucleotide polymorphism) genotyping protocols like RAD (Restriction-site associated DNA) sequencing or hybrid capture allow for the isolation of thousands of markers from any...

Some semelparous species show terminal investment by suicidal offspring provisioning. This requires internal cellular disintegration for the production of regurgitated food and in preparation for the sacrifice of the female body to the offspring, however, we have limited insights into the extent and costs of such physiological modifications. Extrem...

When females can mate multiply, the interests of both sexes over female remating may not coincide, leading to selection for adaptations and counteradaptations in males and females. In several orb-weaving spiders, males damage external structures of the female genitalia during copulation, which hinders the female from remating. We investigated wheth...

Dwarf spiders are of special interest due to their sexually dimorphic prosomal structures in males. Glandular secretions within these structures serve as nuptial gifts, and thus sexual selection may have contributed to their high species richness. However, species diversity of dwarf spiders in East Asia is yet understudied. Here, we review the erig...

The female internal reproductive anatomy of two mantophasmatodean species, Karoophasma biedouwense and Viridiphasma clanwilliamense, is described in detail using X-ray micro-computed tomography, light microscopy, and scanning electron microscopy. We identified paired ovaries containing panoistic ovarioles, a spermatheca surrounded by an epithelium...

In order to avoid sperm competition, males of many taxa apply physical barriers, so-called mating plugs, into female genitalia. Females may control which males deposit a plug through pre-copulatory mate choice or by influencing plug efficacy to avoid costs imposed by plugging. However, subsequent suitors might remove the plugs. We investigated beha...

Spiders show a wide range of sensory capabilities as evidenced by behavioural observations. Accordingly, spiders possess diverse sensory structures like mechano-, hygro-, thermo- or chemoreceptive sensilla. As to chemoreceptive structures, only trichoid tip-pore sensilla were found so far that were tested for gustation. That spiders are also able t...

The central nervous system is known to be plastic in volume and structure depending on the stimuli the organism is subjected to. We tested in the jumping spider Marpissa muscosa (Clerck, 1757), whether rearing environments affect the volume of two target higher-order brain centers: the mushroom body (MB) and the arcuate body (AB). We reared female...

The anatomy of the female genitalia sets the arena for sperm competition in species in which females mate multiply and store sperm. In spiders, females possess cuticular internal structures that have evolved into diverse sperm storage sites. Here, we investigate the female genital morphology of seven eresid spider species. We used X-ray micro-compu...

The investigation of the type series of Oulema septentrionis (Weise, 1880) and Oulema erichsonii (Suffrian, 1841) using Micro-computed X-ray tomography (µCT) revealed that neither species is a melanic variant of Oulema melanopus (Linnaeus, 1758) as has been suggested previously. Lectotypes of Oulema septentrionis (Weise, 1880) and Oulema erichsonii...

Sperm competition may select for male reproductive traits that influence female mating or oviposition rate. These traits may induce fitness costs to the female; however, they may be costly for the males as well as any decrease in female fitness also affects male fitness. Male adaptations to sperm competition manipulate females by altering not only...

Division of reproductive behaviour and alloparental care are key aspects of many animal societies. In cooperatively breeding species, variation in helping effort and unequal task participation are frequently observed. However, the extent to which the reproductive state of an individual affects the tasks performed during offspring care remains poorl...

The primary function of male copulatory organs is depositing spermatozoa directly into the female reproductive tract. Typical male copulatory organs are sensorily active. This is in contrast to the copulatory organs of male spiders (i.e. palpal bulbi), which have been assumed to lack nerves and muscles until recently. Neurons have been found within...

A methodological insight into electrophysiological recordings to test for a gustatory and olfactory function of tip-pore sensilla on the body appendages of the wasp-spider Argiope bruennichi is given.

The interplay between pre- and postmating responses to intrasexual competition remains enigmatic. Sperm competition models often assume a trade-off between pre- and postmating traits that enhance mate acquisition and fertilization success, respectively. However, when males court females through food donations (i.e., nuptial gifts), pre- and postmat...

Jumping spiders are known for their extraordinary cognitive abilities. The underlying nervous system structures, however, are largely unknown. Here, we explore and describe the anatomy of the brain in the jumping spider Marpissa muscosa (Clerck, 1757) by means of paraffin histology, X-ray microCT analysis and immunohistochemistry as well as three-d...

Bipolar distributions of benthic taxa have intrigued many biologists since the firstAntarctic expeditions. Records of taxa, either at species or higher taxonomic levels, encompassing this peculiar distribution have been regularly reported since then. Moreover, the study of heterobranch mollusks from remote areas, such as Antarctica, often provides...

Although several studies are devoted to determining the diversity of Antarctic heterobranch sea slugs, new species are still being discovered. Among nudibranchs, Doto antarctica Eliot, 1907 is the single species of this genus described from Antarctica hitherto, the type locality being the Ross Sea. Doto antarctica was described mainly using externa...

Reconstructed anatomy of the anterior region of Doto carinova Moles, Avila & Wägele n. sp. It can be opened in Adobe Acrobat Reader and activated by clicking on it. Each system and organ can be selected independently. (PDF)

Accession numbers of the species included in the phylogenetic analysis. Species sequenced in this study are in bold. (DOCX)

A common male adaptation to prevent sperm competition is the placement of a mating plug. Such plugs are considered as an extreme investment if they comprise parts of the genital systems and render the male sterile. Genital mutilation occurs in monogynous spiders of several families and may co-occur with permanent sperm depletion, meaning that sperm...

The analysis of cuticular extracts from the cleptoparasitic spider Argyrodes elevatus revealed the presence of unusual esters, new for arthropods. These novel compounds proved to be methyl-branched long chain fatty acid esters with methyl branches located either close or remote from the internally located ester group. GC/MS analysis of the prosoma...

Aim: The phylogeographical history of wide-ranging Palaearctic species is not well understood. Here, we present a range-wide phylogeographical study of the wasp spider, Argiope bruennichi (Scopoli, 1772), a highly dispersive and widely distributed Palaearctic species. We aim to identify glacial refugia and patterns of interglacial gene flow across...