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1.
This paper aims to clarify terminological differences that have arisen between two different field studies of gelada baboons (Theropithecus gelada). First, a comparison of age classifications is made to show the physical correspondences between the two sets of classes. Second, the social system of the gelada baboon is outlined and the terms used to refer to the components of this system are defined and clarified. Attention is drawn to the complex structure of gelada society and to the relationship between the superficially similar social systems of the gelada and the hamadryas baboon.  相似文献   

2.
Summary. The genetic distances separating 14 Spanish goat breeds are calculated from gene frequency data of 14 genetic blood markers (GSH, Ke, Hb, Dia, Ct, MDH, CA, X, NP, Alp, Am, Cp, Tf and Al).
Working from the matrix of Nei's genetic distances we drew a dendrogram demonstrating a great genetic similarity among populations from Negra Serrana, Zamorana, Guadarrama, Retinta, Blanca Andaluza, Berciana and Pirenaica on one hand; and Canaria, Murciana, Blanca Celtibérica, Verata, Palmera, Malaguena and Granadina on the other.
We discuss the similarities and differences within our classification using gene frequency data of the blood genetic markers studied, and classifications based chiefly on morphological and production data.  相似文献   

3.
The genetic distances separating 14 Spanish goat breeds are calculated from gene frequency data of 14 genetic blood markers (GSH, Ke, Hb, Dia, Ct, MDH, CA, X, NP, Alp, Am, Cp, Tf and Al). Working from the matrix of Nei's genetic distances we drew a dendrogram demonstrating a great genetic similarity among populations from Negra Serrana, Zamorana, Guadarrama, Retinta, Blanca Andaluza, Berciana and Pirenaica on one hand; and Canaria, Murciana, Blanca Celtibérica, Verata, Palmera, Malague?a and Granadina on the other. We discuss the similarities and differences within our classification using gene frequency data of the blood genetic markers studied, and classifications based chiefly on morphological and production data.  相似文献   

4.
In this paper we define two types of formal biological entities corresponding to biological levels of organization, thebiolons and theorgons, the properties of which are phenomenologically analyzed and discussed.We examine then, in a rather speculative manner, how some characteristics of these entities may suggest analogies between properties of biological systems and some special features of quantum systems.These analogies are principally related to the specific roles played by these entities (relatively to matter-energy, for orgons, and to information, for biolons) in a biological system. They are funded on the formal equivalence between the temporal variations associated to the development of the orgons and the biolons, respectively, and the statistical distribution over the available energy levels of the two main types of quantum entities, the fermions and the bosons (the former being associated to the constitution of matter and the latter to the effects of interactions).This formal comparison leads us to put into correspondences the developmental duration in biological systems with the energetic structuration in quantum ones and the related characteristic times of the former with the temperature of the latter. We discuss briefly these correspondences.  相似文献   

5.
A brief review of the contemporary theoretical concepts of homology being developed basically in systematics and phylogenetics as well as in developmental biology is presented. Ontologically, both homology and analogy represent a kind of correspondence considered from the standpoint of nominalism, realism, and conceptualism. According to their nominalistic treatment, both are described by a set-theory approximation which makes them classes (in the logical sense). The realistic treatment provides their holistic view according to which a homologue is an anatomical or evolutionary singular while analogue remains a class. The conceptualistic treatment means that there are real (objective) correspondences existing among real (objective) entities while fixation of any of them is based on certain theoretical presumptions adopted by a researcher; homology as a natural kind (including homeostatic property cluster) seems to be most consistent with such a treatment. Realistic view of homology makes it "absolute", while two others make discrimination of homology and analogy strictly relative. Two basic general homology concepts have been developed in recent literature--taxic and transformational ones; the first considers respective correspondences as structure relations, the second as process relations. The taxic homology is nearly the same as classical typological one (Owen), while transformational homology unites all its phylogenetic, ontogenetic (developmental) and transformation-typological definitions. Process-structuralistic approach seems to unite both taxic and transformational ones. The latter makes it possible to apply general homology concept not only to structures but to processes as well. It is stressed that homology is not identical to the similarity, the latter being just the means for revealing the former. Some closer consideration is given to phylogenetic, ontogenetic and genetic treatments of homology; significant uncertainty is shown to exist between them which causes the "homology problem". Epistemologically, any homology statement has a status of hypothesis which makes such a statement theory-dependent according to the hypothetic-deductive argumentation scheme. This dependence allows to stress once more the relative nature of homology and analogy correspondences. Some questions concerning operational concepts and criteria of homology are considered. A hierarchical concept of homology seems to be the most promising prospect of future development of the "homology problem".  相似文献   

6.
By means of 14 restriction enzymes, we have studied the kinetoplast DNA polymorphism in 21 Trypanosoma cruzi isolates previously classified into 19 different genotypes based on the analysis of 15 isozyme loci. We have found a high correlation (p less than 0.001) between the proportion of restriction bands (fragments) common to any two given isolates and the corresponding genetic identities calculated from the isozyme data. This shows that the two classifications (kDNA and isozymes) corrobate one another and strongly suggests that the two types of variability are correlated with time (molecular clocks). The phylogenic classifications so obtained can be used as rational bases for medical and epidemiological studies. Although they are correlated, the two types of analysis are complementary as they do not yield identical results. Like the isozyme genetic distances and genetic identities, the values obtained for the proportion of common restriction bands (fragments) exhibit a continuum. This seems to confirm that natural T. cruzi populations exhibit a wide range of genotypes rather than a few well-differentiated clusters of strains.  相似文献   

7.
This paper describes a new vegetation classification for the Greater Maya Mountains of Belize, focusing primarily on the Chiquibul Forest Reserve. Extensive use is made of GIS, remote sensing, botanical collections and field visits to provide a macro‐ and meso‐scale overview of the vegetation of this region. A total of 32 vegetation classes have been defined, both geographically and structurally, including 11 new classes. Where possible, classes have been compared with earlier classifications. A dominant scaling technique has been used to enable direct comparison between ground truthing data and a supervised Maximum Likelihood Classifier image‐based vegetation classification. The merits of such classifications and the effect of scale are discussed.  相似文献   

8.
Application of optical classifications to North European lakes   总被引:1,自引:0,他引:1  
Two classifications (rough and fine) based on the optical properties of water were used to classify 42 Estonian, Finnish, and Swedish lakes. The rough classification was based on the amount of optically active substances (OAS: chlorophyll a, suspended matter, and colored dissolved organic matter) in the water. The basic variables of the fine classification were chlorophyll a concentration, beam attenuation coefficient of light in the photosynthetically active radiation (PAR) region in the water (or corresponding Secchi depth), and the beam attenuation coefficient for filtered water at 380 nm. All optical classes were represented in the studied lakes by both classifications, when they changed their class depending on the seasonal and biological conditions. In a large lake, different parts of the lake belonged to different optical classes. The results obtained by both classifications were in good agreement. There was a concurrence between optical classes and water transparency by Secchi depth. Often the bio-optical variations of water properties are described from the measurements of all three OAS and Secchi depth because these parameters belong to routine monitoring datasets and have been carefully recorded. The water classes provide a method to summarize the influences of the different factors.  相似文献   

9.
The genetic structure of the population of Ferrara Province in the Po delta in Italy was investigated using chi 2 analysis, kinship analysis, analysis of correspondences, and geographical mapping of principal components of gene frequencies. chi 2 Analysis tests for Hardy-Weinberg equilibrium and for heterogeneity of gene and phenotype frequencies; kinship analysis tests for association between indicators of genetic and geographic proximity; analysis of correspondences relates localities and genetic systems in an eigenvectorial space; and geographic mapping displays the principal components of gene frequencies in the real space. In 1,364 adults in 26 residential units, seven presumably neutral isoenzyme systems were typed; ACP1 ESD, GLO I, GPT, PGD, PGM1 and PGP. It was found that average kinship for these neutral systems is correlated with geographic distance in this small area, but not as strongly as kinship for beta-thalassemia. A north-south gradient was observed for ESD. Analysis of correspondences indicated GPT, PGM1, and GLO I as the systems contributing most to differentiation within the province. The maps obtained from principal components of gene frequencies were consistent with the migrational history of the area.  相似文献   

10.
Classification of 16S RNA sequences over their frequency dictionaries, both real ones, and transformed ones was studied. Two entities were considered to be close each other from the point of view of their structure, if their frequency dictionaries were close, in Eucledian metric. A transformation procedure of a frequency dictionary has been implemented that reveals the peculiarities of information structure of a nucleotide sequence. A comparative study of two classification developed over the real frequency dictionary vs. that one developed over the transformed frequency dictionary was carried out. The strong correlation is revealed between the classification and the taxonomy of 16S RNA bearer. For the classes isolated, the information valuable words were identified. These words are the main factors of a difference between the classes. The frequency dictionaries containing the words of the length 3 exhibit the best correlation between a class and a genus. A genus, as a rule, is included into the same class, and the exclusion are sporadic. A development of hierarchy classification over the transformed frequency dictionaries separated one or two taxonomy groups, as each stage of classification. The unexpectedly frequent, or contrary, unexpectedly rare occurred of words (of the length 3) in entities under consideration make the structure difference between the classes of the nucleotide sequences.  相似文献   

11.
Hybridization between wild species and their domestic counterparts may represent a major threat to natural populations. However, high genetic similarity between the hybridizing taxa makes the detection of hybrids a difficult task and may hinder attempts to assess the impact of hybridization in conservation biology. In this work, we used a combination of 42 autosomal microsatellites together with Y-chromosome microsatellite-defined haplotypes and mtDNA sequences to investigate the occurrence and dynamics of wolf-dog hybridization in the Iberian Peninsula. To do this, we applied a variety of Bayesian analyses and a parallel set of simulation studies to evaluate (i) the differences between Iberian wolves and dogs, (ii) the frequency and geographical distribution of hybridization and (iii) the directionality of hybridization. First, we show that Iberian wolves and dogs form two well-differentiated genetic entities, suggesting that introgressive hybridization is not a widespread phenomenon shaping both gene pools. Second, we found evidence for the existence of hybridization that is apparently restricted to more peripheral and recently expanded wolf populations. Third, we describe compelling evidence suggesting that the dynamics of hybridization in wolf populations is mediated by crosses between male dogs and female wolves. More importantly, the observation of a population showing the occurrence of a continuum of hybrid classes forming mixed packs may indicate that we have underestimated hybridization. If future studies confirm this pattern, then an intriguing avenue of research is to investigate how introgression from free-ranging domestic dogs is enabling wolf populations to adapt to the highly humanized habitats of southern Europe while still maintaining their genetic differentiation.  相似文献   

12.
Standard microbial evolutionary ontology is organized according to a nested hierarchy of entities at various levels of biological organization. It typically detects and defines these entities in relation to the most stable aspects of evolutionary processes, by identifying lineages evolving by a process of vertical inheritance from an ancestral entity. However, recent advances in microbiology indicate that such an ontology has important limitations. The various dynamics detected within microbiological systems reveal that a focus on the most stable entities (or features of entities) over time inevitably underestimates the extent and nature of microbial diversity. These dynamics are not the outcome of the process of vertical descent alone. Other processes, often involving causal interactions between entities from distinct levels of biological organisation, or operating at different time scales, are responsible not only for the destabilisation of pre-existing entities, but also for the emergence and stabilisation of novel entities in the microbial world. In this article we consider microbial entities as more or less stabilised functional wholes, and sketch a network-based ontology that can represent a diverse set of processes including, for example, as well as phylogenetic relations, interactions that stabilise or destabilise the interacting entities, spatial relations, ecological connections, and genetic exchanges. We use this pluralistic framework for evaluating (i) the existing ontological assumptions in evolution (e.g. whether currently recognized entities are adequate for understanding the causes of change and stabilisation in the microbial world), and (ii) for identifying hidden ontological kinds, essentially invisible from within a more limited perspective. We propose to recognize additional classes of entities that provide new insights into the structure of the microbial world, namely “processually equivalent” entities, “processually versatile” entities, and “stabilized” entities.  相似文献   

13.
14.
Delineating regions is an important first step in understanding the evolution and biogeography of faunas. However, quantitative approaches are often limited at a global scale, particularly in the marine realm. Reef fishes are the most diversified group of marine fishes, and compared to most other phyla, their taxonomy and geographical distributions are relatively well known. Based on 169 checklists spread across all tropical oceans, the present work aims to quantitatively delineate biogeographical entities for reef fishes at a global scale. Four different classifications were used to account for uncertainty related to species identification and the quality of checklists. The four classifications delivered converging results, with biogeographical entities that can be hierarchically delineated into realms, regions and provinces. All classifications indicated that the Indo-Pacific has a weak internal structure, with a high similarity from east to west. In contrast, the Atlantic and the Eastern Tropical Pacific were more strongly structured, which may be related to the higher levels of endemism in these two realms. The “Coral Triangle”, an area of the Indo-Pacific which contains the highest species diversity for reef fishes, was not clearly delineated by its species composition. Our results show a global concordance with recent works based upon endemism, environmental factors, expert knowledge, or their combination. Our quantitative delineation of biogeographical entities, however, tests the robustness of the results and yields easily replicated patterns. The similarity between our results and those from other phyla, such as corals, suggests that our approach may be of broad utility in describing and understanding global marine biodiversity patterns.  相似文献   

15.
M. Ba  G. Diallo 《IRBM》2013,34(1):56-59
The proliferation of biomedical applications, which rely on different knowledge organization systems, such as ontologies and thesauri raises the issue of the automated identification of the correspondences between these models, in particular for the data integration need. A significant effort has been conducted for tackling this issue of ontology alignment. However, few systems are able to deal with ontologies containing tens of thousands of entities, as it may be the case in the biomedical domain where resources such as SNOMED-CT, the FMA or the NCI thesaurus are commonly used. We present in this paper ServOMap, an efficient system for large-scale ontology alignment. It relies on an Ontology Server (ServO) and uses Information Retrieval techniques for computing similarity between entities. The system participated with two configurations in the 2012 Ontology Alignment Evaluation Initiative campaign. We report the very promising results obtained by the system for large biomedical ontologies alignment. ServOMap is freely available for download at http://code.google.com/p/servo/.  相似文献   

16.
Abstract

An « index weighing » characters for monothetic classifications. — The Author, according to the classification principles of maximization, presents an index in order to value in what measure characters may be considered good for monothetic classifications. The index is given by the ratio between the average similarity within a set of entities exhibiting the character whose importance we want to ascertain and the average similarity that such entities have with those not exhibiting it.  相似文献   

17.
Where structural similarities between molecular ligands are suspected in competitive binding, these similarities may be represented by a set of correspondences between analogous ligand points in the two molecules. This paper describes an algorithm which searches through all possible sets of this form, to find the one which gives the best geometric fit between matched points. Two parameters are supplied to the algorithm, giving the number of correspondences required and the tolerance permitted in the fit. A tree-search technique is used, and methods are described which prune the tree and thus limit the search. The marine neurotoxins, saxitoxin and tetrodotoxin, are used to test a computer implementation of the procedure.  相似文献   

18.
The phenomenon of species extinction raises more and more concern among ecologists facing the actual crisis of biodiversity. Scientific investigations of the causes and effects of extinction must be completed by a philosophical analysis of the concept of extinction that aims to clarify the meanings of the term 'extinction' and to analyse modalities, criteria and degrees of extinction. We will focus our attention on the apparent paradox of the possible 'resurrection' of species in the near future with the help of genetic biotechnology and cloning techniques. The ontological background of the extinction concept is analysed in relation to the idea of species as classes. We will also show that there is no simple analogy between death and species extinction, and develop a conceptualist and dualistic system of supra-individual entities (species vs. population), supported by an instrumentalist approach to genetic manipulations which transform species into interactive kinds, which can go extinct and be recreated.  相似文献   

19.
Analyzing morphological characters in a phylogenetic context comprises two steps, character analysis and cladistic analysis, which are equivalent to two independent tests for hypotheses on homology. The concept of homology concerns comparable parts of the same or different organisms if their correspondences are the consequence of the same genetic or epigenetic information, and consequently of the same origin. The concept of homology is more inclusive than the character concept. Characters are seen as parts of transformation series. In the first step of morphological character analyses correspondences and non-correspondences between two characters are analyzed. A range of different examination methods and accurate study contribute to the severity of test. The hypothesis that two characters are homologous is corroborated if the correspondences outweigh the non-correspondences because the non-correspondences contradict the homology hypothesis whereas the correspondences contradict the analogy hypothesis. Complex characters possess a higher empirical content than less complex characters because they are more severely testable. The cladistic analysis tests characters against other characters which have all passed the first test. Characters which are congruent with the most parsimonious topology are further corroborated; incongruent characters are not seen as ‘falsified’ but as not further corroborated and subject to re-analysis. To test both homologies and topologies repeatedly is consistent with Popperian testability, and it is in such cycles of research that hypotheses will be critically re-evaluated.  相似文献   

20.
Recent studies have detailed a remarkable degree of genetic and linguistic diversity in Northern Island Melanesia. Here we utilize that diversity to examine two models of genetic and linguistic coevolution. The first model predicts that genetic and linguistic correspondences formed following population splits and isolation at the time of early range expansions into the region. The second is analogous to the genetic model of isolation by distance, and it predicts that genetic and linguistic correspondences formed through continuing genetic and linguistic exchange between neighboring populations. We tested the predictions of the two models by comparing observed and simulated patterns of genetic variation, genetic and linguistic trees, and matrices of genetic, linguistic, and geographic distances. The data consist of 751 autosomal microsatellites and 108 structural linguistic features collected from 33 Northern Island Melanesian populations. The results of the tests indicate that linguistic and genetic exchange have erased any evidence of a splitting and isolation process that might have occurred early in the settlement history of the region. The correlation patterns are also inconsistent with the predictions of the isolation by distance coevolutionary process in the larger Northern Island Melanesian region, but there is strong evidence for the process in the rugged interior of the largest island in the region (New Britain). There we found some of the strongest recorded correlations between genetic, linguistic, and geographic distances. We also found that, throughout the region, linguistic features have generally been less likely to diffuse across population boundaries than genes. The results from our study, based on exceptionally fine-grained data, show that local genetic and linguistic exchange are likely to obscure evidence of the early history of a region, and that language barriers do not particularly hinder genetic exchange. In contrast, global patterns may emphasize more ancient demographic events, including population splits associated with the early colonization of major world regions.  相似文献   

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