Technique of Generation of Scenario for Simulation Within the Area Evolutionary Models (Szenariogenerierungstechnik fur Simulationen im Bereich Evolutionare Modelle)

2003 ◽  
Author(s):  
Martin Signer
Keyword(s):  
Author(s):  
William D. Hopkins ◽  
Cheryl D. Stimpson ◽  
Chet C. Sherwood

Bonobos and chimpanzees are two closely relates species of the genus Pan, yet they exhibit marked differences in anatomy, behaviour and cognition. For this reason, comparative studies on social behaviour, cognition and brain organization between these two species provide important insights into evolutionary models of human origins. This chapter summarizes studies on socio-communicative competencies and social cognition in chimpanzees and bonobos from the authors’ laboratory in comparison to previous reports. Additionally, recent data on species differences and similarities in brain organization in grey matter volume and distribution is presented. Some preliminary findings on microstructural brain organization such as neuropil space and cellular distribution in key neurotransmitters and neuropeptides involved in social behaviour and cognition is presented. Though these studies are in their infancy, the findings point to potentially important differences in brain organization that may underlie bonobo and chimpanzees’ differences in social behaviour, communication and cognition. Les bonobos et les chimpanzés sont deux espèces du genus Pan prochement liées, néanmoins ils montrent des différences anatomiques, comportementales et cognitives marquées. Pour cette raison, les études comparatives sur le comportement social, la cognition et l’organisation corticale entre ces deux espèces fournissent des idées sur les modèles évolutionnaires des origines humaines. Dans ce chapitre, nous résumons des études sur les compétences socio-communicatives et la cognition sociale chez les chimpanzés et les bonobos de notre laboratoire en comparaison avec des rapports précédents. En plus, nous présentons des données récentes sur les différences et similarités d’organisation corticale du volume et distribution de la matière grise entre espèces. Nous présentons plus de résultats préliminaires sur l’organisation corticale microstructurale comme l’espace neuropile et la division cellulaire dans des neurotransmetteurs clés et les neuropeptides impliqués dans le comportement social et la cognition. Bien que ces études sont dans leur enfance, les résultats montrent des différences d’organisation corticale importantes qui sont à la base des différences de comportement social, la communication et la cognition entre les bonobos et les chimpanzés.


1998 ◽  
Vol 11 (1) ◽  
pp. 363-363
Author(s):  
Johanna Jurcsik ◽  
Benjamin Montesinos

FG Sagittae is one of the most important key objects of post-AGB stellar evolutionary studies. As a consequence of a final helium shell flash, this unique variable has shown real evolutionary changes on human time scales during this century. The observational history was reviewed in comparison with predictions from evolutionary models. The central star of the old planetary nebula (Hel-5) evolved from left to right in the HR diagram, going in just hundred years from the hot region of exciting sources of planetary nebulae to the cool red supergiant domain just before our eyes becoming a newly-born post-AGB star. The effective temperature of the star was around 50,000 K at the beginning of this century, and the last estimates in the late 1980s give 5,000-6,500 K. Recent spectroscopic observations obtained by Ingemar Lundström show definite changes in the nebular line intensities. This fact undoubtedly rules out the possibility that, instead of FG Sge, a hidden hot object would be the true central star of the nebula. Consequently, the observed evolutionary changes are connected with the evolution of a single star.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Marta Skowron Volponi ◽  
Luca Pietro Casacci ◽  
Paolo Volponi ◽  
Francesca Barbero

Abstract Background The endless struggle to survive has driven harmless species to evolve elaborate strategies of deceiving predators. Batesian mimicry involves imitations of noxious species’ warning signals by palatable mimics. Clearwing moths (Lepidoptera: Sesiidae), incapable of inflicting painful bites or stings, resemble bees or wasps in their morphology and sometimes imitate their behaviours. An entirely unexplored type of deception in sesiids is acoustic mimicry. We recorded the buzzing sounds of two species of Southeast Asian clearwing moths, Heterosphecia pahangensis and H. hyaloptera and compared them to their visual model bee, Tetragonilla collina, and two control species of bees occurring in the same habitat. Recordings were performed on untethered, flying insects in nature. Results Based on eight acoustic parameters and wingbeat frequencies calculated from slow-motion videos, we found that the buzzes produced by both clearwing moths highly resemble those of T. collina but differ from the two control species of bees. Conclusions Acoustic similarities to bees, alongside morphological and behavioural imitations, indicate that clearwing moths display multimodal mimicry of their evolutionary models.


2011 ◽  
Vol 96 (3) ◽  
pp. 207-229 ◽  
Author(s):  
Marta Casanellas ◽  
Jesús Fernández-Sánchez

2018 ◽  
Vol 44 (1) ◽  
pp. 20
Author(s):  
Eloiza Teles Caldart ◽  
Helena Mata ◽  
Cláudio Wageck Canal ◽  
Ana Paula Ravazzolo

Background: Phylogenetic analyses are an essential part in the exploratory assessment of nucleic acid and amino acid sequences. Particularly in virology, they are able to delineate the evolution and epidemiology of disease etiologic agents and/or the evolutionary path of their hosts. The objective of this review is to help researchers who want to use phylogenetic analyses as a tool in virology and molecular epidemiology studies, presenting the most commonly used methodologies, describing the importance of the different techniques, their peculiar vocabulary and some examples of their use in virology.Review: This article starts presenting basic concepts of molecular epidemiology and molecular evolution, emphasizing their relevance in the context of viral infectious diseases. It presents a session on the vocabulary relevant to the subject, bringing readers to a minimum level of knowledge needed throughout this literature review. Within its main subject, the text explains what a molecular phylogenetic analysis is, starting from a multiple alignment of nucleotide or amino acid sequences. The different software used to perform multiple alignments may apply different algorithms. To build a phylogeny based on amino acid or nucleotide sequences it is necessary to produce a data matrix based on a model for nucleotide or amino acid replacement, also called evolutionary model. There are a number of evolutionary models available, varying in complexity according to the number of parameters (transition, transversion, GC content, nucleotide position in the codon, among others). Some papers presented herein provide techniques that can be used to choose evolutionary models. After the model is chosen, the next step is to opt for a phylogenetic reconstruction method that best fits the available data and the selected model. Here we present the most common reconstruction methods currently used, describing their principles, advantages and disadvantages. Distance methods, for example, are simpler and faster, however, they do not provide reliable estimations when the sequences are highly divergent. The accuracy of the analysis with probabilistic models (neighbour joining, maximum likelihood and bayesian inference) strongly depends on the adherence of the actual data to the chosen development model. Finally, we also explore topology confidence tests, especially the most used one, the bootstrap. To assist the reader, this review presents figures to explain specific situations discussed in the text and numerous examples of previously published scientific articles in virology that demonstrate the importance of the techniques discussed herein, as well as their judicious use.Conclusion: The DNA sequence is not only a record of phylogeny and divergence times, but also keeps signs of how the evolutionary process has shaped its history and also the elapsed time in the evolutionary process of the population. Analyses of genomic sequences by molecular phylogeny have demonstrated a broad spectrum of applications. It is important to note that for the different available data and different purposes of phylogenies, reconstruction methods and evolutionary models should be wisely chosen. This review provides theoretical basis for the choice of evolutionary models and phylogenetic reconstruction methods best suited to each situation. In addition, it presents examples of diverse applications of molecular phylogeny in virology.


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