Sepia Officinalis Research Articles

The cuttlebone development of Common Cuttlefish [Sepia officinalis (Linneaus, 1758)

Sepia officinalis’in onemli embriyonik gelisim kriterlerinden biri olan ic kabuk gelisimi 30 safhalik embriyonik gelisim surecinde detayli olarak yeniden tanimlanmistir. Safha 24+(XIV)’da subye kemigi olusumu baslamistir ve kalsiyum karbonattan olusan kalkerli yapi gorulebilmektedir. Safha 26(XV-XVI)’da subye kemiginde ilk bolme gorulebilir, ancak henuz hava ile dolmamistir. Safha 27(XVI-XVII)’de ilk bolme tam olarak olusmustur, jelatinimsi akiskan yerini hava kabarciklarina birakmistir. Safha 30(XX)’da yumurtadan yeni cikmis juvenil 7-8 arasinda bolme iceren ic kabuga sahiptir

Postnatal persistence of episodic spontaneous rapid-body-movement bursts and twitches in the cuttlefish, Sepia officinalis

Measurements made under microscopic examination of spontaneous motility shortly before and after hatching in the cuttlefish, Sepia officinalis, revealed a developmental continuity wherein bursts of vigorous mantle contractions lasting a few seconds at most, often associated with irregular twitching of the tentacles and head (but less often of the eyes or chromatophores), follow each other at variable intervals ranging from less than 5 s to many minutes. Releasing the animals prematurely into sea water had no qualitative effect on visible movements but augmented their incidence considerably if done several days before hatching, while reducing it if done shortly prior to hatching. That this was not an age effect is suggested by the lack of any difference between the two groups after their emergence from the egg capsule. The temporal patterning of these stereotyped ‘rapid-body-movements’, defined here as an immature subclass of ‘motorically active sleep’, differed both quantitatively and qualitatively from the repetitive bouts of swimming (‘active wakefulness’) that also occur episodically in hatchlings but not in embryos. Similar to endothermic vertebrates, sleep bursts in cuttlefish rapidly became much less frequent with increasing age as the incidence of wake-like behaviour increased. Spontaneous embryonic motility, c.q., active sleep, thus appears to constitute an ontogenetically and phylogenetically primordial behavioural state which continues without discontinuity into postnatal life, with classical ‘rapid-eye-movement’, c.q., ‘paradoxical’ sleep, being a later appearing special case.

Maturation of polarization and luminance contrast sensitivities in cuttlefish (Sepia officinalis)

Polarization sensitivity is a characteristic of the visual system of cephalopods. It has been well documented in adult cuttlefish, which use polarization sensitivity in a large range of tasks such as communication, orientation and predation. Because cuttlefish do not benefit from parental care, their visual system (including the ability to detect motion) must be efficient from hatching to enable them to detect prey or predators. We studied the maturation and functionality of polarization sensitivity in newly hatched cuttlefish. In a first experiment, we examined the response of juvenile cuttlefish from hatching to the age of 1 month towards a moving, vertically oriented grating (contrasting and polarized stripes) using an optomotor response apparatus. Cuttlefish showed differences in maturation of polarization versus luminance contrast motion detection. In a second experiment, we examined the involvement of polarization information in prey preference and detection in cuttlefish of the same age. Cuttlefish preferentially chose not to attack transparent prey whose polarization contrast had been removed with a depolarizing filter. Performances of prey detection based on luminance contrast improved with age. Polarization contrast can help cuttlefish detect transparent prey. Our results suggest that polarization is not a simple modulation of luminance information, but rather that it is processed as a distinct channel of visual information. Both luminance and polarization sensitivity are functional, though not fully matured, in newly hatched cuttlefish and seem to help in prey detection.

Sübye [Sepia officinalis (Linneaus, 1758)]’nin iç kabuk gelişimi

Sübye [Sepia officinalis (Linneaus, 1758)]’nin iç kabuk gelişimi

An extreme biomimetic approach: hydrothermal synthesis of β-chitin/ZnO nanostructured composites

β-Chitinous scaffolds isolated from the skeleton of marine cephalopod Sepia officinalis were used as a template for the in vitro formation of ZnO under conditions (70 °C) which are extreme for biological materials. Novel β-chitin/ZnO film-like composites were prepared for the first time by hydrothermal synthesis, and were thoroughly characterized using numerous analytical methods including Raman spectroscopy, HR-TEM and XRD. We demonstrate the growth of hexagonal ZnO nanocrystals on the β-chitin substrate. Our chitin/ZnO composites presented in this work show antibacterial properties against Gram positive bacteria and can be employed for development of inorganic-organic wound dressing materials.

Fractionation and Enzymatic Characterization of Endoprotease and Exopeptidase from Crude Extracts of Cuttlefish Sepia officinalis Hepatopancreas

This study examines the optimal fractionation method and conditions for the isolation of endoprotease- and exopeptidase-active fractions from crude extracts of cuttlefish hepatopancreas (HP) using four fractionation methods: ammonium sulfate fractionation (ASF), polyethylene glycol fractionation (PGF), ion exchange chromatography (IEC), and gel filtration chromatography (GFC). Total endoprotease activity highest in the fraction II (concentrate of fractions 34-42; 842.60 U) of GFC, followed by fraction III (40-60% ammonium sulfate fraction; 670.25 U) of ASF, fraction I (concentrate of fractions 8-12; 436.89 U) of IEC, and fraction II (10-20% polyethylene glycol; 307.31 U) of PGF. Total exopeptidase activity of these fractions was highest in fraction II (2,704.70 U) of GFC, fraction III (2,110.50 U) of ASF, fraction III (1,605.60 U) of PGF, and fraction II (concentrate of fractions 38-44; 1,196.22 U) of IEC. These results showed that fraction II of GFC had the highest activity toward both exopeptidase and endoprotease, with exopeptidase activity being 3.21 times higher than of endoprotease. These results suggest cuttlefish HP could be used as a potential source for the extraction of exopeptidase, an enzyme capable of catalyzing the cleavage of N- and C-terminal amino acids in polypeptides, Like endoprotease, the most efficient method for separating exopeptide-active fractions was GFC.

Good handling practices of the catch: The effect of early icing on the freshness quality of cuttlefish (Sepia officinalis L.)

Three postharvest icing treatments were implemented on cuttlefish specimens (overall number = 243) after they were hauled onboard: T1-ICO, storage under a 15-mm-thick layer of contact crushed freshwater ice; T2-ICA, storage over a 15-mm-thick layer of contact crushed freshwater ice; T3-NOI, storage without any contact ice, but placed over a 15-mm-thick layer of contact crushed freshwater ice once ashore. All storage trials (n = 6) were conducted at 2 ± 2 °C and were terminated on the sixth day of storage because the aim of the study was to evaluate the effect of realistic icing practices on the freshness quality and shelf -life of cuttlefish, as assessed by sensory (a non-destructive Quality Index Method, QIM), physical (dielectric properties through the Fish Freshness Meter, “295 – Torrymeter”) and chemical (the breakdown products of adenosine 5′–triphosphate, or ATP, as well as relevant ratios among them) methods.The early use of contact ice, either above (T1-ICO) or underneath (T2-ICA) single-layered cuttlefish placed in self-draining polystyrene boxes, was able to slow down ATP degradation. Nevertheless, because three visual traits were significantly worsened in the former treatment, the T2-ICA treatment was suggested as the most proper icing procedure for this cephalopod. The Torrymeter readings had no utility either for predicting the cuttlefish actual/remaining shelf-life for each icing treatment, or for discriminating among them. The percentage ratio between hypoxanthine (Hx) and adenosine 5′–monophosphate (AMP) proved to be the chemical index most highly correlated with ice days. A useful, non-destructive, QIM scheme for cuttlefish was successfully tried and tested in the process.

Quantification of cuttlefish (Sepia officinalis) camouflage: a study of color and luminance using in situ spectrometry

Cephalopods are renowned for their ability to adaptively camouflage on diverse backgrounds. Sepia officinalis camouflage body patterns have been characterized spectrally in the laboratory but not in the field due to the challenges of dynamic natural light fields and the difficulty of using spectrophotometric instruments underwater. To assess cuttlefish color match in their natural habitats, we studied the spectral properties of S. officinalis and their backgrounds on the Aegean coast of Turkey using point-by-point in situ spectrometry. Fifteen spectrometry datasets were collected from seven cuttlefish; radiance spectra from animal body components and surrounding substrates were measured at depths shallower than 5 m. We quantified luminance and color contrast of cuttlefish components and background substrates in the eyes of hypothetical di- and trichromatic fish predators. Additionally, we converted radiance spectra to sRGB color space to simulate their in situ appearance to a human observer. Within the range of natural colors at our study site, cuttlefish closely matched the substrate spectra in a variety of body patterns. Theoretical calculations showed that this effect might be more pronounced at greater depths. We also showed that a non-biological method ("Spectral Angle Mapper"), commonly used for spectral shape similarity assessment in the field of remote sensing, shows moderate correlation to biological measures of color contrast. This performance is comparable to that of a traditional measure of spectral shape similarity, hue and chroma. This study is among the first to quantify color matching of camouflaged cuttlefish in the wild.

A preliminary estimate of the trophic position of the deep-water ram’s horn squid Spirula spirula based on the nitrogen isotopic composition of amino acids

The ram’s horn squid, Spirula spirula (Spirulida, Coleoidea), inhabits subsurface waters of the tropical and subtropical oceans. Because of the presence of an internal chambered shell in this species, it has frequently been used as a model species to investigate the paleobiology of fossil coleoids. However, the feeding and dietary habits of S. spirula in the nature are poorly known. In this study, we applied a new method (amino acid nitrogen isotopic analysis) to estimate the trophic position of S. spirula specimens captured off Suriname, as well as three cuttlefish Sepia species (Sepia officinalis, S. latimanus, and S. esculenta), with a calcified chambered shell from the shallower water. The trophic position of S. spirula was estimated to be 2.5–2.8, which was significantly lower than that for the three Sepia species (3.4–3.6). The results and available data on the gastric contents of S. spirula suggest that it feeds mainly on detritus and zooplankton, including crustaceans, from the overlying water column. The method used in this study can potentially be applied to the estimation of the trophic position of the fossil cephalopods having calcified chambered shells.

Tri-axial accelerometers tease apart discrete behaviours in the common cuttlefish Sepia officinalis

Acceleration data loggers can be used to construct time–energy budgets or identify specific behaviours in free living animals. Within a marine context such devices have been largely deployed on vertebrates with comparatively little attention paid to commercially important invertebrates such as cephalopod molluscs. Here we tested the utility of tri-axial accelerometers to tease apart six discrete behaviours in the common cuttlefish Sepia officinalis. By considering depth profiles in conjunction with body pitch and roll and overall dynamic body acceleration we were able to make distinctions between resting at the seabed, active swimming, mating, post-coital panting and active manoeuvring along the seabed.

Does exposure to noise from human activities compromise sensory information from cephalopod statocysts?

Many anthropogenic noise sources are nowadays contributing to the general noise budget of the oceans. The extent to which sound in the sea impacts and affects marine life is a topic of considerable current interest both to the scientific community and to the general public. Cepaholopods potentially represent a group of species whose ecology may be influenced by artificial noise that would have a direct consequence on the functionality and sensitivity of their sensory organs, the statocysts. These are responsible for their equilibrium and movements in the water column. Controlled Exposure Experiments, including the use of a 50–400Hz sweep (RL=157±5dB re 1μPa with peak levels up to SPL=175dB re 1μPa) revealed lesions in the statocysts of four cephalopod species of the Mediterranean Sea, when exposed to low frequency sounds: (n=76) of Sepia officinalis, (n=4) Octopus vulgaris, (n=5) Loligo vulgaris and (n=2) Illex condietii. The analysis was performed through scanning (SEM) and transmission (TEM) electron microscopical techniques of the whole inner structure of the cephalopods' statocyst, especially on the macula and crista. All exposed individuals presented the same lesions and the same incremental effects over time, consistent with a massive acoustic trauma observed in other species that have been exposed to much higher intensities of sound: Immediately after exposure, the damage was observed in the macula statica princeps (msp) and in the crista sensory epithelium. Kinocilia on hair cells were either missing or were bent or flaccid. A number of hair cells showed protruding apical poles and ruptured lateral plasma membranes, most probably resulting from the extrusion of cytoplasmic material. Hair cells were also partially ejected from the sensory epithelium, and spherical holes corresponding to missing hair cells were visible in the epithelium. The cytoplasmic content of the damaged hair cells showed obvious changes, including the presence of numerous vacuoles and electron-dense inclusions not seen in the control animals. The lesions described here are new to cephalopod pathology. Given that low-frequency noise levels in the ocean are increasing (e.g. shipping, offshore industry, and naval manoeuvres), that the role of cephalopods in marine ecosystems is only now beginning to be understood, and that reliable bioacoustic data on invertebrates are scarce, the present study and future investigations will bring an important contribution to the sustainable use of the marine environment.

A Complex Set of Sex Pheromones Identified in the Cuttlefish Sepia officinalis

BackgroundThe cephalopod mollusk Sepia officinalis can be considered as a relevant model for studying reproduction strategies associated to seasonal migrations. Using transcriptomic and peptidomic approaches, we aim to identify peptide sex pheromones that are thought to induce the aggregation of mature cuttlefish in their egg-laying areas.ResultsTo facilitate the identification of sex pheromones, 576 5′-expressed sequence tags (ESTs) were sequenced from a single cDNA library generated from accessory sex glands of female cuttlefish. Our analysis yielded 223 unique sequences composed of 186 singletons and 37 contigs. Three major redundant ESTs called SPα, SPα′ and SPβ were identified as good candidates for putative sex pheromone transcripts and are part of the 87 unique sequences classified as unknown. The alignment of translated SPα and SPα′ revealed a high level of conservation, with 98.4% identity. Translation led to a 248-amino acid precursor containing six peptides with multiple putative disulfide bonds. The alignment of SPα-α′ with SPβ revealed a partial structural conservation, with 37.3% identity. Translation of SPβ led to a 252-amino acid precursor containing five peptides. The occurrence of a signal peptide on SPα, SPα′ and SPβ showed that the peptides were secreted. RT-PCR and mass spectrometry analyses revealed a co-localization of transcripts and expression products in the oviduct gland. Preliminary in vitro experiments performed on gills and penises revealed target organs involved in mating and ventilation.ConclusionsThe analysis of the accessory sex gland transcriptome of Sepia officinalis led to the identification of peptidic sex pheromones. Although preliminary functional tests suggested the involvement of the α3 and β2 peptides in ventilation and mating stimulation, further functional investigations will make it possible to identify the complete set of biological activities expected from waterborne pheromones.

The use of different anaesthetics as welfare promoters during short-term human manipulation of European cuttlefish (Sepia officinalis) juveniles

Anaesthetics are frequently used to prevent injuries, stress and to promote welfare while handling animals. The efficiency of five anaesthetics for short-term handling of the European cuttlefish (Sepia officinalis) was tested in order to determine the best agent and its concentration. Ethanol (10.0, 20.0 and 30.0mL.L−1), clove oil (0.05, 0.15mL.L−1), hypothermia (8°C), magnesium chloride (hexahydrated; 20.0, 27.0g.L−1) and AQUI-S® (10.9μl.L−1) were the selected anaesthetics. This choice was preceded by a preliminary trial, with additional agents, where 2-phenoxyethanol (10, 15, 20, 30mL.L−1) and MS-222® (30, 40mg.L−1) were used. Due to the lack of reliable results from these two agents, they were discarded. Anaesthetic procedure was performed in 85 cuttlefish juveniles with a mean wet weight of 45.69±12.01g, on a 5L container, under hyper-oxygenated seawater (~200%), plus the dose of a given anaesthetic agent. After achieving induction, cuttlefish were handled for 180s, which consisted in a weighing procedure according to a developed CCMAR protocol. Recovery from anaesthesia was performed in a tank with flow-through hyper-oxygenated water. All these procedures were video recorded and used to, a posteriori, obtain the time frames of induction, handling and recovery, as well as for the behaviour analysis during each stage.For the analysis of results and taking into account the best welfare practice, we established the following time period criteria to determine the optimum anaesthetic dose: induction<600s; and recovery <900s. Data gathered was used to build a descriptive table of behaviour related stages based on all the anaesthetic agents, which was then also used to analyse the individual data.Despite the multitude of new anaesthetics developed for marine vertebrates, with this work we verified that MgCl2, at 27g.L−1, is still the anaesthetic agent to be used in short-term handling of cuttlefish. Relative to other agents used, MgCl2 proved superior in ease of application, price, availability, and its minimal distressing effect on individuals. However, it's of utmost importance to increase the knowledge regarding this species physiology related to the field of animal welfare. The development of tools for the identification of possible biomolecular indicators of stress in cuttlefish and the confirmation of similar physiology to vertebrates will allow a correct verification of stress induction and reduction, when using an anaesthetic agent and during the handling process.

Ocean acidification and temperature rise: effects on calcification during early development of the cuttlefish Sepia officinalis

This study investigated the effects of seawater pH (i.e., 8.10, 7.85 and 7.60) and temperature (16 and 19 °C) on (a) the abiotic conditions in the fluid surrounding the embryo (viz. the perivitelline fluid), (b) growth, development and (c) cuttlebone calcification of embryonic and juvenile stages of the cephalopod Sepia officinalis. Egg swelling increased in response to acidification or warming, leading to an increase in egg surface while the interactive effects suggested a limited plasticity of the swelling modulation. Embryos experienced elevated pCO2 conditions in the perivitelline fluid (>3-fold higher pCO2 than that of ambient seawater), rendering the medium under-saturated even under ambient conditions. The growth of both embryos and juveniles was unaffected by pH, whereas 45Ca incorporation in cuttlebone increased significantly with decreasing pH at both temperatures. This phenomenon of hypercalcification is limited to only a number of animals but does not guarantee functional performance and calls for better mechanistic understanding of calcification processes.

Influence of Temperature, Hypercapnia, and Development on the Relative Expression of Different Hemocyanin Isoforms in the Common Cuttlefish Sepia officinalis

The cuttlefish Sepia officinalis expresses several hemocyanin isoforms with potentially different pH optima, indicating their reliance on efficient pH regulation in the blood. Ongoing ocean warming and acidification could influence the oxygen-binding properties of respiratory pigments in ectothermic marine invertebrates. This study examined whether S. officinalis differentially expresses individual hemocyanin isoforms to maintain optimal oxygen transport during development and acclimation to elevated seawater pCO(2) and temperature. Using quantitative PCR, we measured relative mRNA expression levels of three different hemocyanin isoforms in several ontogenetic stages (embryos, hatchlings, juveniles, and adults), under different temperatures and elevated seawater pCO(2). Our results indicate moderately altered hemocyanin expression in all embryonic stages acclimated to higher pCO(2), while hemocyanin expression in hatchlings and juveniles remained unaffected. During the course of development, total hemocyanin expression increased independently of pCO(2) or thermal acclimation status. Expression of isoform 3 is reported for the first time in a cephalopod in this study and was found to be generally low but highest in the embryonic stages (0.2% of total expression). Despite variable hemocyanin expression, hemolymph total protein concentrations remained constant in the experimental groups. Our data provide first evidence that ontogeny has a stronger influence on hemocyanin isoform expression than the environmental conditions chosen, and they suggest that hemocyanin protein abundance in response to thermal acclimation is regulated by post-transcriptional/translational rather than by transcriptional modifications.

Impact of ocean warming on the early ontogeny of cephalopods: a metabolic approach

The impact of a realistic warming scenario on the metabolic physiology of early cephalopod (squid Loligo vulgaris and cuttlefish Sepia officinalis) life stages was investigated. During exposure to the warming conditions (19 °C for the western coast of Portugal in 2100), the increase in oxygen consumption rates throughout embryogenesis was much steeper in squid (28-fold increase) than in cuttlefish (11-fold increase). The elevated catabolic activity–accelerated oxygen depletion within egg capsules, which exacerbated metabolic suppression toward the end of embryogenesis. Squid late-stage embryos appear to be more impacted by warming via metabolic suppression than cuttlefish embryos. At all temperature scenarios, the transition from encapsulated embryos to planktonic paralarvae implied metabolic increments higher than 100 %. Contrary to the nektobenthic strategy of cuttlefish newborns, the planktonic squid paralarvae rely predominantly on pulsed jet locomotion that dramatically increases their energy requirements. In the future, hatchlings will require more food per unit body size and, thus, feeding intake success will be crucial, especially for squid with high metabolic rates and low levels of metabolic reserves.

ESI-MS and MALLS analysis of quaternary structure of molluscan hemocyanins

The understanding of the function of macromolecular complexes is mainly related to a precise knowledge of their structure. Recently, the development of suitable mass spectrometric techniques (electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI)) and multi-angle laser light scattering has enabled mass determination of native complexes and of their subunits. By these techniques, the structure and association/dissociation behavior of huge molecules of molluscan Octopus vulgaris, Sepia officinalis and Rapana venosa have been characterized. Molecular masses of the native and dissociated molecule of cephalopodan Hcs O. vulgaris (3545 and 359.3 kDa, respectively) and S. officinalis (4134 and 443.8 kDa, respectively) revealed that only one type subunit organizes their molecules, while the presence of two isoforms with different masses (422.8 and 400.0 kDa) has been determined for gastropodan R. venosa Hc, aggregated into didecamers. The difference of their structural subunits was also established after limited proteolysis with TPCK-trypsin. Eight functional units (FUs) with masses of ~ 50 kDa were isolated from both subunits of RvH and isoform of Sepia officinalis, while seven FUs were purified from OvH. Further characterization of proteins by ESI-mass spectrometry (MS) and MALDI-MS, methods gave insights into post-translational modifications such as glycosylation. Glycosylation of O. vulgaris and S. officinalis Hcs was suggested based on the differences (11.6 and 40.0 kDa, respectively) between the masses measured by ESI-MS and those calculated by their gene sequences.

A Preliminary Analysis of Sleep-Like States in the Cuttlefish Sepia officinalis

Sleep has been observed in several invertebrate species, but its presence in marine invertebrates is relatively unexplored. Rapid-eye-movement (REM) sleep has only been observed in vertebrates. We investigated whether the cuttlefish Sepia officinalis displays sleep-like states. We find that cuttlefish exhibit frequent quiescent periods that are homeostatically regulated, satisfying two criteria for sleep. In addition, cuttlefish transiently display a quiescent state with rapid eye movements, changes in body coloration and twitching of the arms, that is possibly analogous to REM sleep. Our findings thus suggest that at least two different sleep-like states may exist in Sepia officinalis.

Cuttlefish bone scaffold for tissue engineering: a novel hydrothermal transformation, chemical-physical, and biological characterization

PurposeNatural resources are receiving growing interest because of their possible conversion from a cheap and easily available material into a biomedical product. Cuttlefish bone from Sepia Officinalis was investigated in order to obtain an hydroxyapatite porous scaffold using hydrothermal transformation. MethodsComplete conversion of the previous calcium carbonate (aragonite) phase into a calcium phosphate (hydroxyapatite) phase was performed with an hydrothermal transformation at 200 °C (∼15 atm), for four hours, with an aqueous solution of KH2PO4 in order to set the molar ratio Ca/P = 10/6 in a reactor (Parr 4382). The complete conversion was then analyzed by TGA, ATR-FTIR, x-ray diffraction, and SEM. Moreover, the material was biologically investigated with MC3T3-E1 in static cultures, using both osteogenic and maintenance media. The expression of osteogenic markers as ALP and osteocalcin and the cell proliferation were investigated. ResultsCuttlefish bone has been successfully transformed from calcium carbonate into calcium phosphate. Biological characterization revealed that osteogenic markers are expressed using both osteogenic and maintenance conditions. Cell proliferation is influenced by the static culture condition used for this three-dimensional scaffold. ConclusionsThe new scaffold composed by hydroxyapatite and derived for a natural source presents good biocompatibility and can be used for further investigations using dynamic cultures in order to improve cell proliferation and differentiation for bone tissue engineering.

Cerebral correlates of visual lateralization in Sepia

The common cuttlefish, Sepia officinalis (cephalopod mollusc) has recently become a relevant model for studying the setting-up of brain asymmetry among invertebrates. As the animals age from 3 to 30 days post hatching, they progressively develop a left-turning bias resulting from an eye-use preference. The aim of this study is to investigate whether anatomical (vertical, peduncle, inferior buccal, and optic lobes) or neurochemical (monoamines in optic lobes) brain asymmetries are present in the cuttlefish brain at 3 or at 30 post hatching days; and whether these correlate with side-turning preferences. We here find brain and behavioral asymmetry only at 30 post hatching days. Cuttlefish displayed a significant population bias towards a larger right peduncle lobe, and higher monoamine concentration in the left optic lobe (i.e. serotonin, dopamine and noradrenaline). None of these brain asymmetries were correlated to the studied side-turning bias. However, we found individual variation in the magnitude of the vertical and optic lobes asymmetry. A striking correlation was found with the behavioral results: the larger the right optic lobe and the right part of the vertical lobe, the stronger the bias to turn leftwards. To our knowledge, this is the first study to demonstrate a relationship at the individual level between brain and behavioral asymmetries in invertebrates.