The ability to perceive and recognise a reflected mirror image as self (mirror self-recognition, MSR) is considered hallmark of cognition across species. Although MSR has been reported in mammals birds, it not known occur any other major taxon. Potentially limiting our test for taxa that the established assay, mark test, requires animals display contingency testing self-directed behaviour. These behaviours may be difficult humans interpret taxonomically divergent animals, especially those...

In animals where males engage in multiple matings, sperm depletion can substantially reduce the reproductive success of both sexes. However, little is known about how successive matings affect depletion, fertilization rates and mating behaviour. Here, we investigated this phenomenon under laboratory conditions. Medaka ( Oryzias latipes ), an externally fertilizing fish, ideal model to test predictions because there are established methods observe its count sperm. mated with females (19 per...

An animal that tries to remove a mark from its body is only visible when looking into mirror displays the capacity for self-recognition (MSR), which has been interpreted as evidence self-awareness. Conservative interpretations of existing data conclude convincing MSR currently restricted great apes. Here, we address proposed shortcomings previous study on in cleaner wrasse Labroides dimidiatus , by varying preexposure mirrors and marking individuals with different colors. We found (1) 14/14...

Some animals have the remarkable capacity for mirror self-recognition (MSR), yet any implications self-awareness remain uncertain and controversial. This is largely because explicit tests of two potential mechanisms underlying MSR are still lacking: mental image self kinesthetic visual matching. Here, we test hypothesis that ability in cleaner fish, Labroides dimidiatus , associated with a self, particular self-face, like humans . Mirror-naive fish initially attacked photograph models both...

Laboratory experiments were conducted using model organisms to elucidate biological phenomena. However, the natural habitats of are inherently more complex than those found in laboratory. To complement laboratory experiments, we field observations small freshwater fish medaka ( Oryzias latipes ), widely used as a organism, its ecology and behavior environments. Our results showed that initiated courtship spawning late at night, much earlier previously thought. Nocturnal video examining time...

Theory suggests that living in large social groups with dynamic interactions often favours the evolution of enhanced cognitive abilities. Studies how animals assess their own contest ability commonly focus on a single task, and little is known about diversity or co-occurrence abilities species. We examined highly cichlid fish Julidochromis transcriptus uses four major situations; direct experience, winner/loser effects, eavesdropping transitive inference (TI). conducted experiments which...

In mutualistic symbiosis, organisms often provide food to their partners. However, the processes and significance of provisioning hosts remain poorly understood. The anemonefish Amphiprion clarkii, which prefers larger hosts, has been suggested its host sea anemone Entacmaea quadricolor. present study, we investigated by effects on symbiotic relationships. When given foods various sizes types in field, selectively consumed small animal (krill, clams, squid, fish) green macroalgae size, while...

Summary Sleep is a ubiquitous process that has been conserved in animals. Yet, our understanding of the functions sleep largely derives from few species. considered to play an important role mental processes, including learning and memory consolidation, but how widespread this relationship across taxa remains unclear. Here, we test impact disruption on ability cleaner fish ( Labroides dimidiatus ) both learn remember novel cognitive task. was disrupted by exposing subset light at set...

<title>Abstract</title> Understanding the biological phenomena in model organisms typically relies on laboratory studies. However, ecological validity of these findings is often uncertain when natural behaviors remain understudied. Medaka (<italic>Oryzias latipes</italic>) a widely used reproductive and behavioral research, but timing its spawning settings has rarely been directly observed. Recent fieldwork suggested that medaka spawn several hours before sunrise, contrasting with common...

ABSTRACT Seminal vesicle (SV) secretions enhance fertilization by regulating sperm motility and capacity, forming plugs that prevent mating with other males. Although SVs are rare in teleosts, certain species, such as Corydoras spp., do possess them. In spp. species exhibit drinking or related behaviors, females attach their mouths to the males' genital pore ingest semen, a reproductive behavior known drinking. However, major proteins functions of seminal fluid (SVF) remain unidentified....

Reproductive timing is a critical ecological trait that directly influences fitness. Medaka (Oryzias latipes), small freshwater fish, widely used as model organism in various scientific fields. However, studies conducted under (semi-) natural conditions remain limited. Although, spawning has been reported to occur within 1 h before and after sunrise, direct observations scarce. We investigated the of initiation associated courtship medaka through 24-h using infrared cameras semi-natural...

Cooperatively breeding animals, in which helpers may participate reproduction with dominant breeders, are ideal species for examining intraspecific variation testis size because they often exhibit both monogamous (low risk of sperm competition) and polyandrous (high risk) within a population. However, little is known about investment as result competition these animals. The substrate-brooding cichlid fish Julidochromis ornatus has cooperatively system, some males mate monogamously other...

1. Communities of different species are often structured according to niche differentiation associated with competitive interactions. We show that similar principles may apply on an ecological time-scale when individuals a having wide size variation compete for resources, using the Lake Tanganyika cichlid Lobochilotes labiatus (5-30 cm). This has mouth especially adapted suck up invertebrates from rock crevices. 2. Individuals defended feeding territories against similar-sized conspecifics,...

Abstract The ability to perceive and recognise a reflected mirror image as self (mirror self-recognition, MSR) is considered hallmark of cognition across species. Although MSR has been reported in mammals birds, it not known occur any other major taxon. A factor potentially limiting the test for that established assay MSR, mark test, shows an interpretation bias towards animals with dexterity (or limbs) required touch mark. Here, we show cleaner wrasse fish, Labroides dimidiatus , passes...

Theories suggest that, in cooperatively breeding species, female control over paternity and reproductive output may affect male skew group stability. Female come about through cryptic choice or behaviour, but experimental studies are scarce. Here, we show a new form of polyandrous cichlid fish ( Julidochromis transcriptus ), which females prefer wedge-shaped nesting sites. Wedge-shaped sites allowed to manipulate the siring success member males by spawning clutch at spot where large were...

Parental roles and the amount of care in bi-parental fish have been assumed to be determined by sex.We studied parental behaviour a substrate brooding cichlid Julidochromis ornatus (40-90 mm total length) which both parents participate eggs young.In study population, ca 80% paired females were larger than their partners pairs mated assortatively for size.Males spent more time with offspring female-largest pairs, whereas opposite was found male-largest pairs.These differences conspicuous when...

Abstract Unravelling the evolution of complex social organization in animals is an important aim, not least because it helps to understand evolutionary roots human sociality. Recent advances comparative methods allow approach this question a phylogenetic context. The validity such approaches depends strongly on quality information regarding behaviour, sociality, and reproduction natural systems, reconstruction. Applying novel approach, recent study Dey et al. ( , Nature Ecology &amp;...

Abstract We investigated the evolutionary relationship between spawning behaviour and sperm motility traits among Tanganyikan mouth‐brooding cichlid species that have developed diverse mating behaviours male sexual traits. Mouth‐brooding is common these fish, but different demonstrate a range of behaviours, bower construction, timing gamete release. observed compared 28 cichlids to elucidate correlations Sperm longevity was considerably longer in bower‐building construct crater‐shaped sites...