scholarly journals Diversity of Olfactory Responses and Skills in Astyanax Mexicanus Cavefish Populations Inhabiting different Caves

Diversity ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 395 ◽  
Author(s):  
Maryline Blin ◽  
Julien Fumey ◽  
Camille Lejeune ◽  
Maxime Policarpo ◽  
Julien Leclercq ◽  
...  
Keyword(s):  
Single Species ◽  
Constant Darkness ◽  
Astyanax Mexicanus ◽  
Olfactory Responses ◽  
In The Wild ◽  
Genetic Mechanisms ◽  
Olfactory Detection ◽  
Northeastern Mexico ◽  
Olfactory Detection Thresholds ◽  
Natural Settings

Animals in many phyla are adapted to and thrive in the constant darkness of subterranean environments. To do so, cave animals have presumably evolved mechano- and chemosensory compensations to the loss of vision, as is the case for the blind characiform cavefish, Astyanax mexicanus. Here, we systematically assessed the olfactory capacities of cavefish and surface fish of this species in the lab as well as in the wild, in five different caves in northeastern Mexico, using an olfactory setup specially developed to test and record olfactory responses during fieldwork. Overall cavefish showed lower (i.e., better) olfactory detection thresholds than surface fish. However, wild adult cavefish from the Pachón, Sabinos, Tinaja, Chica and Subterráneo caves showed highly variable responses to the three different odorant molecules they were exposed to. Pachón and Subterráneo cavefish showed the highest olfactory capacities, and Chica cavefish showed no response to the odors presented. We discuss these data with regard to the environmental conditions in which these different cavefish populations live. Our experiments in natural settings document the diversity of cave environments inhabited by a single species of cavefish, A. mexicanus, and highlight the complexity of the plastic and genetic mechanisms that underlie cave adaptation.

scholarly journals A whole genome analysis of the red-crowned crane provides insight into avian longevity

2017 ◽  
Author(s):  
HyeJin Lee ◽  
Oksung Chung ◽  
Yun Sung Cho ◽  
Sungwoong Jho ◽  
JeHoon Jun ◽  
...  
Keyword(s):  
Metabolic Rate ◽  
Whole Genome ◽  
Whole Genome Analysis ◽  
Grus Japonensis ◽  
Low Genetic Diversity ◽  
In Captivity ◽  
In The Wild ◽  
Genetic Mechanisms ◽  
Avian Genomes ◽  
Insight Into

AbstractThe red-crowned crane (Grus japonensis) is an endangered and large-bodied crane native to East Asia. It is a traditional symbol of longevity and its long lifespan has been confirmed both in captivity and in the wild. Lifespan in birds is positively correlated with body size and negatively correlated with metabolic rate; although the genetic mechanisms for the red-crowned crane’s long lifespan have not previously been investigated. Using whole genome sequencing and comparative evolutionary analyses against the grey-crowned crane and other avian genomes, we identified candidate genes that are correlated with longevity. Included among these are positively selected genes with known associations with longevity in metabolism and immunity pathways (NDUFA5, NDUFA8, NUDT12 IL9R, SOD3, NUDT12, PNLIP, CTH, and RPA1). Our analyses provide genetic evidence for low metabolic rate and longevity, accompanied by possible convergent adaptation signatures among distantly related large and long-lived birds. Finally, we identified low genetic diversity in the red-crowned crane, consistent with its listing as an endangered species, and we hope this genome will provide a useful genetic resource for future conservation studies of this rare and iconic species.

How Giraffes Work

2021 ◽  
Author(s):  
Graham Mitchell
Keyword(s):  
Single Species ◽  
Free Living ◽  
Factors Affecting ◽  
Normal Functions ◽  
Private Lives ◽  
Social Biology ◽  
Biochemical Systems ◽  
In The Wild ◽  
Physiological And Biochemical ◽  
Biological Milieu

There are few creatures more beautiful, more aloof, and more fascinating than giraffes. Once they were plentiful and filled African landscapes, but in 2016 they were re-classified from “least concern” to “vulnerable” by the International Union for Conservation of Nature. Their survival in the wild is not assured. Much has been written about their private lives, about their behavior, social biology, and ecology, and their history in art and diplomacy. But so far no book has been written about their private lives, their physiology, and their anatomy and biochemistry—in short, the normal functions of a free-living animal in its natural environment—and it is these aspects of their lives that are the focus of this book. The study of a single species could be concise and relatively simply told. In reality it is not. A species never evolves in isolation from the general biological milieu in which it finds itself. Tectonics, astronomical physics, climate, and purely biological factors affecting food and water resources all shape the path of their evolution and all interact with its morphology, its internal physiological and biochemical systems, and the behavior patterns that regulate its daily life. Giraffes are no exception, as is revealed as the story told here unfolds. How do giraffes work? The answers lie in a story filled not only with the internal workings of a unique creature, but with geography, climate changes of great magnitude, and the labors of extraordinary people who put many pieces of the puzzle together.

scholarly journals III. Resin canals in the canadian spruce (Picea canadensis (Mill.) B. S. P.)-An anatomical study, especially in relation to traumatic effects and their bearing on phylogeny

1926 ◽  
Vol 214 (411-420) ◽  
pp. 63-111 ◽  
Keyword(s):  
Anatomical Study ◽  
Single Species ◽  
Adjacent Area ◽  
Local Material ◽  
Nursery Stock ◽  
In The Wild ◽  
Secondary Wood ◽  
Resin Canals ◽  
Conifer Wood ◽  
Selection Of

Every student of conifer wood structure is familiar with the importance that in modern anatomical work is attached to the occurrence and distribution of resin canals. It is apparent in classification, identification, and, above all, in discussions of phylogeny. For example, the Pineæ are said to be distinguished by the normal occurrence of resin canals throughout the secondary wood, the Abieteæ by their occurrence practically only in response to wounding. The canals in the latter case are considered by some as being “revived” by injury and by others as in the process of acquirement. However, important though resin canals undoubtedly are, too little is known with regard to them to warrant many of the prevailing conclusions. There has been no systematic study of their origin and distribution, even in a single species. It was to make a beginning towards the filling in of this gap in our knowledge that the present study was undertaken. The spruce was chosen partly because of the abundance of local material, both in nurseries and in the wild state. In fact, although nursery stock was ultimately made use of to perhaps a greater extent than the material from the woods, the study could probably not have been completed on this material alone, so obscure did the principle underlying the distribution of the resin canals seem when viewed merely from a study of nursery plants. There were, however, additional reasons of a scientific nature for the selection of the genus Picea. The resin canals, occurring apparently normally in the wood, are not nearly so abundant as they are in the pines, and are more irregular in distribution. Two low-power photographs have been made to illustrate these points. In Picea sometimes resin canals are completely lacking in an annual ring, whereas in the adjacent area they are fairly abundant (Plate 8, Photo. 1), but not so numerous nor so evenly distributed as they are in the pine, where every ring of the section shows several (Photo. 2); nor is their radial distribution in the year's growth uniform. They occur at various regions in either spring or summer wood, even to the very borders of both, although usually they are more abundant in the earlier part of the season's growth. The distribution of what are ordinarily considered normal .resin canals is thus very sporadic in Picea. Again, in the region of wounds, tangential series quite like those so frequently figured as typical of Abies, are plentiful ( cf . Photos. 23 and 24, Plate 9, the former of Picea, the latter of Abies).

scholarly journals Urban biodiversity: an insight into the terrestrial vertebrate diversity of Guwahati, India

2018 ◽  
Vol 10 (10) ◽  
pp. 12299-12316
Author(s):  
Jayaditya Purkayastha
Keyword(s):  
Threatened Species ◽  
Single Species ◽  
Iucn Red List ◽  
Red List ◽  
Urban Biodiversity ◽  
Terrestrial Vertebrate ◽  
In The Wild ◽  
Insight Into

This study focuses on the assessment of the terrestrial vertebrate diversity of Guwahati.  Twenty-six species of amphibians, 57 species of reptiles, 214 species of birds, and 36 species of mammals were recorded during the study period.  Thirty-three species were found to be threatened with extinction and another 62 species need evaluation.  A single species of turtle was found to be categorized as Extinct in the Wild under the IUCN Red List of Threatened Species. 

scholarly journals Olfactory Detection Thresholds for Primary Aliphatic Alcohols in Mice

2020 ◽  
Vol 45 (7) ◽  
pp. 513-521 ◽  
Author(s):  
Ellie Williams ◽  
Adam Dewan
Keyword(s):  
Sensory System ◽  
Relative Sensitivity ◽  
Ideal Gas ◽  
Aliphatic Alcohols ◽  
Neural Mechanisms ◽  
Odorant Receptors ◽  
Frequent Use ◽  
Nonideal Gas ◽  
Olfactory Detection ◽  
Olfactory Detection Thresholds

Abstract Probing the neural mechanisms that underlie each sensory system requires the presentation of perceptually appropriate stimulus concentrations. This is particularly relevant in the olfactory system as additional odorant receptors typically respond with increasing stimulus concentrations. Thus, perceptual measures of olfactory sensitivity provide an important guide for functional experiments. This study focuses on aliphatic alcohols because they are commonly used to survey neural activity in a variety of olfactory regions, probe the behavioral limits of odor discrimination, and assess odor-structure activity relationships in mice. However, despite their frequent use, a systematic study of the relative sensitivity of these odorants in mice is not available. Thus, we assayed the ability of C57BL/6J mice to detect a homologous series of primary aliphatic alcohols (1-propanol to 1-heptanol) using a head-fixed Go/No-Go operant conditioning assay combined with highly reproducible stimulus delivery. To aid in the accessibility of our data, we report the animal’s threshold to each odorant according to the 1) ideal gas condition, 2) nonideal gas condition (factoring in the activity of the odorant in the solvent), and 3) the liquid dilution of the odorant in the olfactometer. Of the odorants tested, mice were most sensitive to 1-hexanol and least sensitive to 1-butanol. These updated measures of murine sensitivity will hopefully guide experimenters in choosing appropriate stimulus concentrations for experiments using these odorants.

scholarly journals The Four Leaf Water Clover (Marsilea Quadrifolia L.) an Endangered Species. Aspects of Conservation and Management

2015 ◽  
Vol 16 (1) ◽  
pp. 161-176 ◽  
Author(s):  
Erika Schneider-Binder
Keyword(s):  
Field Research ◽  
Single Species ◽  
Leaf Water ◽  
European Countries ◽  
Habitat Directive ◽  
Ecological Requirements ◽  
Marsilea Quadrifolia ◽  
Bern Convention ◽  
In The Wild ◽  
Upper Rhine

Abstract The European species of the genus Marsilea are presented, with special regard to Four leaf water clover Marsilea quadrifolia L., the single species occurring in Central Europe. Based on field research on the Upper Rhine in Germany and the Lower Danube in Romania the ecological requirements of the species and the plant communities in which the species lives are analysed and compared with data from other European countries. Due to the decline of the species populations as a consequence of human activities, all European Marsilea species are rare, vulnerable, endangered by extinction or extinct in the wild and included in the Red data books of most European countries. Also all the European water clovers Marsilea strigosa, Marsilea batardae and Marsilea quadrifolia have been included in the Appendix I of the Bern Convention (1979) as strictly protected species and in the Annexe II of the European Flora Fauna Habitat Directive 92/43/1992. After analysis of ecological conditions, the state of conservation and the Red List categories of Marsilea quadrifolia following IUCN criteria in the countries of occurrence are presented and possible measures for conservation are discussed as well as realised reintroduction of the species in the wild

scholarly journals Envoy, a PAS/LOV Domain Protein of Hypocrea jecorina (Anamorph Trichoderma reesei), Modulates Cellulase Gene Transcription in Response to Light

2005 ◽  
Vol 4 (12) ◽  
pp. 1998-2007 ◽  
Author(s):  
Monika Schmoll ◽  
Lisa Franchi ◽  
Christian P. Kubicek
Keyword(s):  
Type Strain ◽  
Wild Type Strain ◽  
Light Response ◽  
Constant Darkness ◽  
Wild Type ◽  
Hypocrea Jecorina ◽  
Lov Domain ◽  
Cellulase Expression ◽  
In The Wild ◽  
Domain Protein

ABSTRACT Envoy, a PAS/LOV domain protein with similarity to the Neurospora light regulator Vivid, which has been cloned due to its lack of expression in a cellulase-negative mutant, links cellulase induction by cellulose to light signaling in Hypocrea jecorina. Despite their similarity, env1 could not compensate for the lack of vvd function. Besides the effect of light on sporulation, we observed a reduced growth rate in constant light. An env1 PAS− mutant of H. jecorina grows significantly slower in the presence of light but remains unaffected in darkness compared to the wild-type strain QM9414. env1 rapidly responds to a light pulse, with this response being different upon growth on glucose or glycerol, and it encodes a regulator essential for H. jecorina light tolerance. The induction of cellulase transcription in H. jecorina by cellulose is enhanced by light in the wild-type strain QM9414 compared to that in constant darkness, whereas a delayed induction in light and only a transient up-regulation in constant darkness of cbh1 was observed in the env1 PAS− mutant. However, light does not lead to cellulase expression in the absence of an inducer. We conclude that Envoy connects the light response to carbon source signaling and thus that light must be considered an additional external factor influencing gene expression analysis in this fungus.

scholarly journals Response of insect swarms to dynamic illumination perturbations

2019 ◽  
Vol 16 (150) ◽  
pp. 20180739 ◽  
Author(s):  
Michael Sinhuber ◽  
Kasper van der Vaart ◽  
Nicholas T. Ouellette
Keyword(s):  
Light Exposure ◽  
Collective Behaviour ◽  
Environmental Perturbations ◽  
Full Control ◽  
In The Wild ◽  
Variable Light ◽  
Classical Thermodynamics ◽  
Natural Settings ◽  
Thermodynamic Phase ◽  
Swarming Behaviour

Many animal species across taxa spontaneously form aggregations that exhibit collective behaviour. In the wild, these collective systems are unavoidably influenced by ubiquitous environmental perturbations such as wind gusts, acoustic and visual stimuli, or the presence of predators or other animals. The way these environmental perturbations influence the animals' collective behaviour, however, is poorly understood, in part because conducting controlled quantitative perturbation experiments in natural settings is challenging. To circumvent the need for controlling environmental conditions in the field, we study swarming midges in a laboratory experiment where we have full control over external perturbations. Here, we consider the effect of controlled variable light exposure on the swarming behaviour. We find that not only do individuals in the swarm respond to light changes by speeding up during brighter conditions but also the swarm as a whole responds to these perturbations by compressing and simultaneously increasing the attraction of individual midges to its centre of mass. The swarm-level response can be described by making an analogy to classical thermodynamics, with the state of the swarm moving along an isotherm in a thermodynamic phase plane.

Exogenous and Endogenous Control of Swimming Activity in Astyanax mexicanus (Characidae, Pisces) by Direct Light Response and by a Circadian Oscillator II. Features of Time-Controlled Behaviour of a Cave Population and their Comparison to a Epigean Ancestral Form

1982 ◽  
Vol 37 (11-12) ◽  
pp. 1266-1273 ◽  
Author(s):  
Wilhelmine Erckens ◽  
Wolfgang Martin
Keyword(s):  
Surface Activity ◽  
Activity Patterns ◽  
Light Response ◽  
Swimming Activity ◽  
Period Length ◽  
Circadian Oscillator ◽  
Constant Darkness ◽  
Control Activity ◽  
Astyanax Mexicanus ◽  
River Fish

Abstract 1. The swimming activity of 6 specimens of the Pachon cave form of Astyanax mexicanus was tested with regard to its time control under various light-dark(LD)cycles and constant conditions, and it is compared to that of a river form. 2. In general, activity is entrainable by all applied LDs, but even if the amplitude of a forcing signal increases the signal energies are lower than in the river fish. 3. In case of entrainment the maximum values of surface activity correspond to the dark phases, those of bottom activity to the light phases of a LD. Flexible patterns -as often observed in the river form in the range of resonance about 24 h - are very seldom. Furthermore, disturbances of­ ten occur in the entrainment of one activity form, or one form runs arrhythmic while the other is still entrained. 4. The activity answers to changing environmental conditions are not as uniformly quick as in the river fish. But the system hardly needs a swing-in time to become entrained when a LD starts. 5. After transition from LD to DD (= constant darkness) the entrained rhythms disappear immediately. 6. In no LD with a period length differing from 24 h a circadian rhythm can be observed in addition to the entrained frequency. 7. These results show that the passive system of the river form has developped into an extremely passive one being unable to oscillate and thus has become simplified during regressive evolution. Concerning the circadian oscillator of the epigean ancestor, it was also subjected to regression, but it has not been completely lost. After a LD with a period length about 24 h the circadian oscillator is able to act as a stable system, clearly shown by the freerunning circadian rhythms of surface activity. But out of this range the oscillator is unable to control activity. In DD after all other LDs activity patterns are arrhythmic.

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