scholarly journals Interspecific variation of antennal lobe composition among four hornet species

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Antoine Couto ◽  
Gérard Arnold ◽  
Hiroyuki Ai ◽  
Jean-Christophe Sandoz
Keyword(s):  
Olfactory System ◽  
Antennal Lobe ◽  
Sensory Modality ◽  
Interspecific Variation ◽  
Insect Brain ◽  
Behavioral Differences ◽  
Vespa Crabro ◽  
Site Preferences ◽  
Adaptive Shifts ◽  
Species Specific

AbstractOlfaction is a crucial sensory modality underlying foraging, social and mating behaviors in many insects. Since the olfactory system is at the interface between the animal and its environment, it receives strong evolutionary pressures that promote neuronal adaptations and phenotypic variations across species. Hornets are large eusocial predatory wasps with a highly developed olfactory system, critical for foraging and intra-specific communication. In their natural range, hornet species display contrasting ecologies and olfactory-based behaviors, which might match to adaptive shifts in their olfactory system. The first olfactory processing center of the insect brain, the antennal lobe, is made of morphological and functional units called glomeruli. Using fluorescent staining, confocal microscopy and 3D reconstructions, we compared antennal lobe structure, glomerular numbers and volumes in four hornet species (Vespa crabro, Vespa velutina, Vespa mandarinia and Vespa orientalis) with marked differences in nesting site preferences and predatory behaviors. Despite a conserved organization of their antennal lobe compartments, glomeruli numbers varied strongly between species, including in a subsystem thought to process intraspecific cuticular signals. Moreover, specific adaptations involving enlarged glomeruli appeared in two species, V. crabro and V. mandarinia, but not in the others. We discuss the possible function of these adaptations based on species-specific behavioral differences.

scholarly journals Distributed representation of social odors indicates parallel processing in the antennal lobe of ants

2011 ◽  
Vol 106 (5) ◽  
pp. 2437-2449 ◽  
Author(s):  
Andreas Simon Brandstaetter ◽  
Christoph Johannes Kleineidam
Keyword(s):  
Parallel Processing ◽  
Olfactory System ◽  
Antennal Lobe ◽  
Activity Patterns ◽  
Insect Brain ◽  
Camponotus Floridanus ◽  
Colony Odor ◽  
Spatial Activity ◽  
Neuronal Representation ◽  
Social Odors

In colonies of eusocial Hymenoptera cooperation is organized through social odors, and particularly ants rely on a sophisticated odor communication system. Neuronal information about odors is represented in spatial activity patterns in the primary olfactory neuropile of the insect brain, the antennal lobe (AL), which is analog to the vertebrate olfactory bulb. The olfactory system is characterized by neuroanatomical compartmentalization, yet the functional significance of this organization is unclear. Using two-photon calcium imaging, we investigated the neuronal representation of multicomponent colony odors, which the ants assess to discriminate friends (nestmates) from foes (nonnestmates). In the carpenter ant Camponotus floridanus, colony odors elicited spatial activity patterns distributed across different AL compartments. Activity patterns in response to nestmate and nonnestmate colony odors were overlapping. This was expected since both consist of the same components at differing ratios. Colony odors change over time and the nervous system has to constantly adjust for this (template reformation). Measured activity patterns were variable, and variability was higher in response to repeated nestmate than to repeated nonnestmate colony odor stimulation. Variable activity patterns may indicate neuronal plasticity within the olfactory system, which is necessary for template reformation. Our results indicate that information about colony odors is processed in parallel in different neuroanatomical compartments, using the computational power of the whole AL network. Parallel processing might be advantageous, allowing reliable discrimination of highly complex social odors.

scholarly journals Body Site and Body Orientation Preferences during Social Grooming: A Comparison between Wild and Captive Chimpanzees and Bonobos

2021 ◽  
pp. 1-12
Author(s):  
Morgane Allanic ◽  
Misato Hayashi ◽  
Takeshi Furuichi ◽  
Tetsuro Matsuzawa
Keyword(s):  
Dominance Rank ◽  
Body Orientation ◽  
Body Site ◽  
Social Variables ◽  
Social Grooming ◽  
Social Differences ◽  
Monkey Species ◽  
Site Preferences ◽  
Risk Of Predation ◽  
Species Specific

Grooming site preferences have been relatively well studied in monkey species in order to investigate the function of social grooming. They are not only influenced by the amount of ectoparasites, but also by different social variables such as the dominance rank between individuals or their levels of affiliation. However, studies on this topic mainly come from monkey species, with almost no report on great apes. This study aimed to explore whether body site and body orientation preferences during social grooming show species-specific differences (bonobos vs. chimpanzees) and environment-specific differences (captivity vs. wild). Results showed that bonobos groomed the head, the front and faced each other more often than chimpanzees, while chimpanzees groomed the back, anogenitals and more frequently in face-to-back positions. Moreover, captive individuals were found to groom facing one another more often than wild ones, whereas wild individuals groomed the back and in face-to-back positions more. While future studies should expand their scope to include more populations per condition, our preliminary 2 by 2 comparison study highlights the influence of (i) species-specific social differences such as social tolerance, social attention and facial communication, and (ii) socioenvironmental constraints such as risk of predation, spatial crowding and levels of hygiene, that might be the two important factors determining the grooming patterns in two <i>Pan</i>species.

Investigating the species-specific association between anuran calling phenology and air temperature

2021 ◽  
Author(s):  
Samantha Wong
Keyword(s):  
Climate Change ◽  
Air Temperature ◽  
Management Strategies ◽  
Temporal Trends ◽  
Interspecific Variation ◽  
Northern Ontario ◽  
Anuran Species ◽  
Calling Behaviour ◽  
Survival And Development ◽  
Species Specific

Climate change has been associated in phenological shifts for a variety of taxa. Amphibians, specifically the order Anura (frogs and toads), are considered particularly vulnerable due to their sensitivity to anthropogenic and environmental change. Previous research has documented shifts in the timing of anuran breeding that can be attributed, in part, to climate change, with potential implications for reproduction, survival, and development. This study aims to investigate how air temperature is associated with anuran calling phenology. I will examine the temporal trends in spring and summer air temperature in a lake in northern Ontario, Canada. and quantify seasonal patterns of calling anuran species using acoustic monitoring over a four-month period. I predict that there will be interspecific variation in peak calling associated with air temperature. Additionally, I expect to find asymmetrical association between air temperature and anuran species’ calling behaviour – wherein prolonged breeding species will have a larger optimal temperature range for calling compared to explosive breeding species. The findings of this research will aid in future conservation and provide insight for management strategies of anurans in Canada in response to anticipated climate warming.

Antennal Lobe Processing Increases Separability of Odor Mixture Representations in the Honeybee

2010 ◽  
Vol 103 (4) ◽  
pp. 2185-2194 ◽  
Author(s):  
Nina Deisig ◽  
Martin Giurfa ◽  
Jean Christophe Sandoz
Keyword(s):  
Antennal Lobe ◽  
Second Order ◽  
Insect Brain ◽  
Output Level ◽  
Local Networks ◽  
Odor Mixture ◽  
Receptor Neurons ◽  
Evoked Activity ◽  
Input Level ◽  
Olfactory Space

Local networks within the primary olfactory centers reformat odor representations from olfactory receptor neurons to second-order neurons. By studying the rules underlying mixture representation at the input to the antennal lobe (AL), the primary olfactory center of the insect brain, we recently found that mixture representation follows a strict elemental rule in honeybees: the more a component activates the AL when presented alone, the more it is represented in a mixture. We now studied mixture representation at the output of the AL by imaging a population of second-order neurons, which convey AL processed odor information to higher brain centers. We systematically measured odor-evoked activity in 22 identified glomeruli in response to four single odorants and all their possible binary, ternary and quaternary mixtures. By comparing input and output responses, we determined how the AL network reformats mixture representation and what advantage this confers for odor discrimination. We show that increased inhibition within the AL leads to more synthetic, less elemental, mixture representation at the output level than that at the input level. As a result, mixture representations become more separable in the olfactory space, thus allowing better differentiation among floral blends in nature.

scholarly journals Multimodal integration and stimulus categorization in putative mushroom body output neurons of the honeybee

2018 ◽  
Vol 5 (2) ◽  
pp. 171785 ◽  
Author(s):  
Martin F. Strube-Bloss ◽  
Wolfgang Rössler
Keyword(s):  
Visual Information ◽  
Mushroom Body ◽  
Visual Cues ◽  
Sensory Modality ◽  
Sensory Information ◽  
Insect Brain ◽  
Pollinating Insects ◽  
Output Neurons ◽  
Electrophysiological Characterization ◽  
Nonlinear Integration

Flowers attract pollinating insects like honeybees by sophisticated compositions of olfactory and visual cues. Using honeybees as a model to study olfactory–visual integration at the neuronal level, we focused on mushroom body (MB) output neurons (MBON). From a neuronal circuit perspective, MBONs represent a prominent level of sensory-modality convergence in the insect brain. We established an experimental design allowing electrophysiological characterization of olfactory, visual, as well as olfactory–visual induced activation of individual MBONs. Despite the obvious convergence of olfactory and visual pathways in the MB, we found numerous unimodal MBONs. However, a substantial proportion of MBONs (32%) responded to both modalities and thus integrated olfactory–visual information across MB input layers. In these neurons, representation of the olfactory–visual compound was significantly increased compared with that of single components, suggesting an additive, but nonlinear integration. Population analyses of olfactory–visual MBONs revealed three categories: (i) olfactory, (ii) visual and (iii) olfactory–visual compound stimuli. Interestingly, no significant differentiation was apparent regarding different stimulus qualities within these categories. We conclude that encoding of stimulus quality within a modality is largely completed at the level of MB input, and information at the MB output is integrated across modalities to efficiently categorize sensory information for downstream behavioural decision processing.

scholarly journals Metagenomic Shotgun Analyses Reveal Complex Patterns of Intra- and Interspecific Variation in the Intestinal Microbiomes of Codfishes

2020 ◽  
Vol 86 (6) ◽  
Author(s):  
Even Sannes Riiser ◽  
Thomas H. A. Haverkamp ◽  
Srinidhi Varadharajan ◽  
Ørnulf Borgan ◽  
Kjetill S. Jakobsen ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Interspecific Variation ◽  
Shotgun Sequencing ◽  
Intestinal Microbiome ◽  
Ecological Niches ◽  
Content Type ◽  
Evolutionary Trajectories ◽  
Species Specific

ABSTRACT The relative importance of host-specific selection or environmental factors in determining the composition of the intestinal microbiome in wild vertebrates remains poorly understood. Here, we used metagenomic shotgun sequencing of individual specimens to compare the levels of intra- and interspecific variation of intestinal microbiome communities in two ecotypes (NEAC and NCC) of Atlantic cod (Gadus morhua) that have distinct behavior and habitats and three Gadidae species that occupy a range of ecological niches. Interestingly, we found significantly diverged microbiomes among the two Atlantic cod ecotypes. Interspecific patterns of variation are more variable, with significantly diverged communities for most species’ comparisons, apart from the comparison between coastal cod (NCC) and Norway pout (Trisopterus esmarkii), whose community compositions are not significantly diverged. The absence of consistent species-specific microbiomes suggests that external environmental factors, such as temperature, diet, or a combination thereof, comprise major drivers of the intestinal community composition of codfishes. IMPORTANCE The composition of the intestinal microbial community associated with teleost fish is influenced by a diversity of factors, ranging from internal factors (such as host-specific selection) to external factors (such as niche occupation). These factors are often difficult to separate, as differences in niche occupation (e.g., diet, temperature, or salinity) may correlate with distinct evolutionary trajectories. Here, we investigate four gadoid species with contrasting levels of evolutionary separation and niche occupation. Using metagenomic shotgun sequencing, we observed distinct microbiomes among two Atlantic cod (Gadus morhua) ecotypes (NEAC and NCC) with distinct behavior and habitats. In contrast, interspecific patterns of variation were more variable. For instance, we did not observe interspecific differentiation between the microbiomes of coastal cod (NCC) and Norway pout (Trisopterus esmarkii), whose lineages underwent evolutionary separation over 20 million years ago. The observed pattern of microbiome variation in these gadoid species is therefore most parsimoniously explained by differences in niche occupation.

scholarly journals Sensitivity in the antioxidant system of discus fish (Symphysodon spp.) to cold temperature: evidence for species-specific cold resistance

2019 ◽  
Author(s):  
Shi-Rong Jin ◽  
Bin Wen ◽  
Zai-Zhong Chen ◽  
Jian-Zhong Gao ◽  
Lei Wang ◽  
...  
Keyword(s):  
Cold Hardiness ◽  
Cold Resistance ◽  
Cold Treatment ◽  
Principal Component ◽  
Interspecific Variation ◽  
Continuous Sequence ◽  
Model Animal ◽  
Set Up ◽  
Species Specific ◽  
Subordinate Function

ABSTRACTThe discus fish (Symphysodon spp.) is an endemic species of the Amazon that is among the most popular ornamental fish around the world, and is usually used as the model animal for studying the diversification of Amazon fish. Here, a comparative analysis of two species of discus fish, i.e., S. haraldi and S. aequifasciatus, based on several antioxidant indexes was conducted, to test the hypothesis that cold resistance might correlate with the diversification of discus fish. We set up a continuous sequence of three temperature programs, namely cooling (28 °C to 14 °C; -1 °C/h), cold maintenance (14 °C for 12 h) and recovery (14 °C to 28 °C; +1 °C/h). Subordinate function (SF) combined with principal component analysis (PCA) showed that the cold hardiness of S. haraldi during cold treatment was in the order of cooling > cold maintenance ≈ recovery, but the cold hardiness of S. aequifasciatus during cold treatment was in the order of cold maintenance > cooling > recovery. Specifically, the lowest cold hardiness was observed in S. aequifasciatus during recovery, indicating that cold stress resulted in more seriously oxidative stress in S. aequifasciatus than in S. haraldi. Overall, these results show a significant interspecific variation, indicating the correlation between environmental adaptation and the diversification of discus fish.

scholarly journals Effects of seasonality, fertilization and species on the chlorophyll a fluorescence as related with photosynthesis and leguminous tree growth during Amazonian forest restoration

2020 ◽  
Author(s):  
Roberto Kirmayr Jaquetti ◽  
José Francisco de Carvalho Gonçalves ◽  
Henrique Eduardo Mendonça Nascimento ◽  
Karen Cristina Pires da Costa ◽  
Jair Max Fortunato Maia ◽  
...  
Keyword(s):  
Electron Transport ◽  
Performance Index ◽  
Forest Restoration ◽  
Cost Effective ◽  
Interspecific Variation ◽  
High Water ◽  
Diameter Growth ◽  
Cost Effective Technique ◽  
Species Specific ◽  
Degraded Ecosystems

AbstractThe ability of species to adjust their light energy uptake is determined during plant establishment and development. Changes in resource availability may impact energy fluxes and photosynthesis. General and specific variations in chlorophyll a fluorescence under high vs. low water and nutrient conditions have been studied. N2-fixing leguminous trees, which are commonly used in tropical forest restoration, seem to be very well adapted to degraded ecosystems. To understand the effects of biological nitrogen fixation on Chl a fluorescence variables, three of the six Fabaceae species selected for this study were N2-fixing species. Additionally, the correlation among Chl a fluorescence and growth, photosynthesis and nutrient levels was evaluated. A 24-month forest restoration experiment was established, and data on dark-adapted Chl a fluorescence, photosynthesis, diameter growth and foliar nutrients were collected. Multivariate analysis was performed to detect the effects of seasonality and fertilization. Under high water- and nutrient-availability conditions, plants exhibited enhanced performance index values that were correlated with electron transport fluxes. Under drought and nutrient-poor conditions, most species exhibited increased energy dissipation as a method of photoprotection. Great interspecific variation was found; therefore, species-specific responses to the test conditions should be considered in future studies. N2-fixing species showed increased performance index and maximum fluorescence values, indicating their ability to colonize high-light environments. Negative correlations were found between photosynthesis and trapped fluxes and between diameter growth and initial fluorescence. Electron transport fluxes were positively correlated with growth. Given the different responses identified among species, Chl a fluorescence is considered a cost-effective technique to screen for seasonality, nutrient and N2-fixing species effects and should be considered for use during forest restoration. Finally, including N2-fixing species and multiple fertilization treatments in related studies may greatly facilitate the restoration of biogeochemical cycles in the tropics.

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