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1.
B. F. J. Manly 《Population Ecology》1975,16(2):219-230
The fitness of animals subjected to natural selection can be defined as the probability of surviving selection for a given interval of time, or some convenient multiple of this probability. If the fitness of animals is related to some quantitative variable X (such as size) then this relationship is expressed mathematically in the fitness function w(x) and this function can be estimated by comparing the distribution of X in samples taken before and after selection. In this note five methods for estimating the fitness function on the basis of samples from a large population are discussed. They are compared on three previously published sets of data and as a result estimation according to weighted multiple regression is recommended. 相似文献
2.
Michael Schlirf 《Pal?ontologische Zeitschrift》2002,76(2):331-338
The ichnospeciesBolonia lata
Meunier, 1886 is a straight, bilobate trace fossil with a somewhat heart-shaped outline in cross-section. It has previously been
reported from various localities mainly from the Jurassic by different authors under various names such asGyrochorte, Scolicia, orProtovirgularia. Because none of these previous determinations fully agrees with the trace fossils’ morphology, the ‘forgotten name’ is reintroduced,
and due to a lack of type material a neotype from the type area of Boulonnais, France is proposed. The ichnogenus is currently
represented only by one ichnospecies,B. lata
Meunier, 1886. Diagnostic criteria ofBolonia and morphologically related trace fossils such asScolicia, Gyrochorte, Bichordites, “Taphrhelminthopsis nelsoni”, andProtovirgularia are discussed, the synonymy ofB. lata is provided and finally a discussion on the possible producer ofBolonia is given.
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3.
Roman Croitor Marie-Françoise Bonifay Jean-Philip Brugal 《Pal?ontologische Zeitschrift》2008,82(3):325-346
New osteological material of the endemic deer from Lunel-Viel and l’Igue des Rameaux (France) reveals its evolutionary specialization,
and gives reason for establishing a new genus,Haploidoceros, with a single speciesH. mediterraneus (Bonifay, 1967). The cranial proportions and morphology suggest thatH. mediterraneus is close to the Late Villafranchian speciesMetacervocerus rhenanus, which may be a possible forerunner of the deer under study. The evolutionary origin ofH. mediterraneus took place in the Iberian glacial refugia during the “Mindel glaciation” of the early Middle Pleistocene. The North-East
distribution ofH. mediterraneus was limited by unfavorable climate influence of the Arctic and Alpine Ice Shields.
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4.
In our previous report [Aita, T., Morinaga, S., Hosimi, Y., 2004. Thermodynamical interpretation of evolutionary dynamics
on a fitness landscape in an evolution reactor I. Bull. Math. Biol. 66, 1371–1403], an analogy between thermodynamics and
adaptive walks on a Mt. Fuji-type fitness landscape in an artificial selection system was presented. Introducing the ‘free
fitness’ as the sum of a fitness term and an entropy term and ‘evolutionary force’ as the gradient of free fitness on a fitness
coordinate, we demonstrated that the adaptive walk (=evolution) is driven by the evolutionary force in the direction in which
free fitness increases. In this report, we examine the effect of various modifications of the original model on the properties
of the adaptive walk. The modifications were as follows: first, mutation distance d was distributed obeying binomial distribution; second, the selection process obeyed the natural selection protocol; third,
ruggedness was introduced to the landscape according to the NK model; fourth, a noise was included in the fitness measurement. The effect of each modification was described in the same
theoretical framework as the original model by introducing ‘effective’ quantities such as the effective mutation distance
or the effective screening size. 相似文献
5.
Walter W. Ferguson 《Primates; journal of primatology》1989,30(3):383-387
A partial mandible with two molars intact was recovered between 1981 and 1984 from deposits of the Middle Pliocene at Tabarin,
in Kenya. It has been described and assigned toAustralopithecus cf.afarensis
Johanson, White, andCoppens, 1978, with the condition that if ‘A. afarensis’ is revised, then the attribution may change. The taxon ‘A. afarensis’ was found to be invalid and was revised. The smaller specimens of ‘A. afarensis,’ to which the Tabarin mandible was said to be similar, were redescribed asHomo antiquus
Ferguson, 1984. Since the Tabarin mandible andH. antiquus are successive transients of the same gens and are allopatric, the Tabarin hominid population is described as an earlier
chronosubspecies,Homo antiquus praegens ssp. n. 相似文献
6.
Anne-Marie Lacoste Mette Poulsen André Cassaigne Eugène Neuzil 《Current microbiology》1979,2(2):113-117
A comparative study was performed on the kinetic properties and the specificity ofd-alanyl-d-alanine ligases fromPseudomonas aeruginosa, Streptococcus faecalis, andStaphylococcus aureus, using some aminophosphonic acids and related compounds.dl-I-Aminoethylphosphonic acid was shown to be a competitive inhibitor of theP. aeruginosa andS. faecalis ligases; assuming ad-form stereospecificity, its activity was nearly equal to that ofd-cycloserine. 2-Aminoethylphosphonate was found to be a weak inhibitor of the ligases, in contrast to the carboxylic analog,
β-alanine. γ-Aminobutyric acid and phosphoethanolamine also exhibited some inhibitory properties. 相似文献
7.
Anew osteostracan genus and species,Victoraspis longicornualis n. gen., n. sp., is described based on material from Rakovets’, present day Ukraine. This new taxon shares characters with
the two generaStensiopelta
Denison, 1951 andZychaspis
Janvier, 1985. A phylogenetic analysis supports the position ofVictoraspis as the sister group to a monophyleticStensiopelta, while the interrelationships of the various species ofZychaspis are poorly resolved. A morphometric analysis is carried out in an attempt to further resolve the taxonomic affinity. This
analysis groups all examinedZychaspis species closely together, and further supports the establishment ofVictoraspis as separate genus.
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8.
Thomas Haack Ma. José González Yolanda Sánchez Ernest Giralt 《International journal of peptide research and therapeutics》1997,4(4-6):377-386
Summary With a few exceptions, proteins in our biosphere are based exclusively onl-amino acids. The inversion of configuration of all the stereogenic centers in a protein leads to anall-d compound with ‘mirror image’ properties and ‘mirror image’ structure. We propose to use the termprotein-enantiomerism to describe the relationship between two proteins that have the same sequence but whose amino acids have opposite configuration.
We will use the termprotein-diastereomerism to define the relationship between two proteins that have the same sequence in which some amino acids have opposite configurations.
A classification of type I, II, III, and IV protein-diastereomerism is proposed. By extension, a diastereoprotein is a protein
where some amino acids have the same configuration (l ord) while others have the opposite one (d orl). A particular case of diastereoproteins aremesoproteins, also analyzed in this article. In addition to the goal of making proteins resistant to protease degradation, the use ofd-amino acids in protein de novo design may give rise to proteins with structures, and perhaps properties, very different to
those of nativeall-l-proteins. 相似文献
9.
On fixed precision level sequential sampling 总被引:1,自引:0,他引:1
Roger H. Green 《Population Ecology》1970,12(2):249-251
Summary It is proposed that the sequential sampling design ofKuno (1969) for estimating populations with a fixed level of precision be modified by using σ2=am
b
for the variance-mean relationship for most field distributions of organisms. This function yields a straight line “stop
line” rather than a curve. An example is calculated and used with field data. 相似文献
10.
Walter W. Ferguson 《Primates; journal of primatology》1989,30(4):561-569
Leonard andHegmon (1987) compare a series of dental metrics of ‘Australopithecus afarensis
Johanson, White, andCoppens, 1978’ with criteria for modern apes, to test the hypothesis that ‘A. afarensis’ represents a single species. They also compare the morphology of the lower third premolar. The dental breadth of ‘A. afarensis’ shows a wide range of variation, particularly in the lower third premolar morphology which displays greater variation than
in modern apes—yet the study concludes that the single species hypothesis cannot be rejected.
The study is flawed by applying criteria for pongids inappropriate for a hominid. When ‘A. afarensis’ is compared with criteria for hominids, the range of variation in dental size, breadth, and third premolar morphology is
greater than that in any hominid species. The single species hypothesis is, therefore, once again rejected. Moreover, the
name ‘A. afarensis’ is preoccupied byPraeanthropus africanus (Weinert) and must be dropped. 相似文献
11.
Yuri A. Popov 《Pal?ontologische Zeitschrift》2007,81(4):429-439
Mainly based on collections from Willershausen (Lower Saxony, North Germany), the Pliocene Heteroptera fauna of West Europe
is briefly revised. The present compilation includes a checklist with taxonomic and systematic corrections ofJordan’s (1967, 1969) type materials. Naucoroid water bugs of the family Aphelocheiridae are distinguished and the extinct species
of the genusAphelocheirus are redescribed. The new genusWillershausenia n.gen. (type species:Nabis strausi
Jordan, 1969) is defined and transferred to the coreoid family Alydidae.
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12.
C. kincaidii, an ectoparasite ofTetragnatha laboriosa
Hentz, was found most commonly in spring and fall. Peak parasitism was 18%. They appeared to oviposit only on middle instar spiderlings,
and winter as larvae attached to spiders.
Résumé C. kincaidii, un ectoparasite deTetragnatha laboriosa Hentz, a été trouvé très communément au printemps et en automne avec un taux de parasitisme maximum de 18%. Il semble pondre seulement sur les stades juvéniles moyens de l’araignée et hiverner à l’état de larves fixées aux araignées adultes.相似文献
13.
Anatol Rapoport 《Bulletin of mathematical biology》1960,22(1):85-97
The derivation of H. D. Landahl’s learning curve (1941,Bull. Math. Biophysics,3, 71–77) from a single information-theoretical assumption obtained previously (Rapoport, 1956,Bull. Math. Biophysics,18, 317–21) is extended to obtain the entire family of such curves with the number of stimuliM (to each of which one ofN responses is to be associated) as a parameter. No additional assumptions are required. The entire family thus appears as
a function of a single free parameter,k, all other parameters being experimentally determined. The theory is compared with a set of experiments involving the learning
of artificial languages. An alternative quasi-neurological model leading to the same equation is offered. 相似文献
14.
Fossil species ofMelanopsis from a freshwater formation in the Jordan Valley (near Al-Qarn) were investigated and the deposits containing these species
are formally described as Al-Qarn Formation. Four species were found:Melanopsis buccinoidea
Olivier,M. tchernovi
Heller & Sivan,M. costata
Olivier andM. aaronsohni
Blanckenhorn.Melanopsis costata was represented by two groups, “stepped” and “non-stepped”, the latter differing in its lower figurativity index. Intermediates
were found betweenM. buccinoidea andM. tchernovi; they may be hybrids. TheMelanopsis assemblage bridges the faunal gap, in the Jordan Valley, between the 2 Ma lake of ‘Erq el Ahmar on the one hand and the 0.8–1.7
Ma lake of ‘Ubeidiya on the other. This suggests an early Pleistocene age of about 1.8 million years for the Al-Qarn Formation. 相似文献
15.
Summary Geological, papaeontological and microfacies studies in the Lower Cambrian carbonate complex of the G?rlitz Synclinorium (eastern
Germany/Saxony/Lusatian region) provide new data for the fossil content, depositional history and palaeogeography. The Lower
Cambrian of the G?rlitz Synclinorium belongs to the facies zones 5, 7 and 8 ofWilson (1975)-platform rim with connections to the open ocean and to the restricted platform areas. An extraordinarily rich fauna
was found with elements which are in some cases new for Europe (Rhombocorniculum cancellatum
Cobbold,Fordilla sibirica
Krasilova, Calodiscus lobatus Hall,Archaeooides granulatus
Qian,Archiasterella pentactina
Sdzuy,Allonia sp.,Obliquatheca aldanica
Sysoiev,Conotheca circumflexa
Missarzhevsky,Microcornus elongatus
Missarzhevsky,Lenalituus sp.,Pelagiella cf.lorenzi
Kobayashi,Beshtashella sp.,Comluella sp.,Cambroclavithidae gen. et sp. indet., Helcionellidae gen. et sp., indet. Eocrinoidea gen. et sp. indet.) This fauna indicates Lower Cambrian
(higher Atdabanian/Botomian) age and reveals palaeobiogeographical connections to the Siberian Platform, to the Mediterranean
area and to China. A somewhat new stratigraphical subdivision of the Lower Cambrian sequence (Zwetau Formation) is described.
New units are established within the Ludwigsdorf Member (the carbonatic lower part of the sequence), the ‘Lower Ludwigsdorf
Member’ (massive dolostone) and the ‘Upper Ludwigsdorf Member’ (bedeed limestones and their equivalents). The subsequentLusatiops Member is subdivided intoSerrodiscus Bed (claystones) andLusatiops Bed (siltstones). 相似文献
16.
Summary
Staphylococcus aureus can be enumerated in foods by the use ofChapman’s special medium (3), under application of the drop plate technique, recommended byMiles andMisra (6).
Colonies ofS.aureus so obtained can easily be macroscopically differentiated from aerobic sporeformers which grow also on this medium. The colonies
can be used immediately for testing their coagulase reaction. 相似文献
17.
The estimation of population size,migration rates and survival in a stratified population 总被引:3,自引:0,他引:3
A. Neil Arnason 《Population Ecology》1973,15(2):1-8
Summary Estimates of survival, migration rates, and population size are developed for a triple catch marking experiment onn (n>-2) areas with migration among all areas and death in all areas occurring, but no recruitment (birth). This repressents the
extension to three sampling times of the method ofChapman andJunge (1956) for estimates in a stratified population. The method is further extented to allow for ‘losses on capture’. 相似文献
18.
Summary This paper deals with four new fungi from the State of Rio Grande do Sul, Brazil.Phaeseptoria stenocalycis
Batista, Upadhyay &Da Costa Netto, collected on leaves ofStenocalyx dasyblastus
Bert. from Grammado,Phoma jasmino-macrospora
Batista, Upadhyay &Da Costa Netto, collected on leaves ofJasminum flexicaule
Vahl. from Pôrto Alegre,Melanconium argutidentis
Batista, Upadhyay &Da Costa Netto, collected on leaves ofSebastiana argutidens
Pex &K. Hoff from Grammado andCercospora caleifoleii
Batista, Upadhyay &Da Costa Netto, collected on leaves ofCalea pinnatifida
Banks from Pôrto Alegre are described here.Symptoms on the hosts and morphological characters of the fruitings and spores are described and illustrated.Publicação no 456 of IMUFP. 相似文献
19.
Nicole Hawlitzky 《BioControl》1979,24(3):237-245
Résumé Quand des œufs d’ages variés (1 h à 5 j) du lépidoptèreAnagasta kuehniella
Zell. sont offerts aux femelles parasites dePhanerotoma flavitestacea
Fisch., l’endroit où l’œuf du parasite est déposé, dépend du stade de développement de l’œuf h?te au moment de l’oviposition.
Lorsque l’œuf h?te est agé de 1 h à 3 j, la ponte a lieu dans le vitellus. Par contre, si l’œuf du parasite est déposé dans
un œuf agé de 4 jours ou plus, il est directement pondu dans l’embryon h?te.
Selon ces résultats, il semble que la pénétration de l’œuf du parasite ou de la larve est due uniquement à un mouvement passif
causé par la migration du vitellus dans le tube digestif moyen de l’embryon h?te.
Ces différents points et l’effet de la piq?re de l’ovipositeur sur l’embryon h?te, la nature de l’élimination des larves surnuméraires
sont discutés.
Summary When lepidopterous eggs of varied ages (1 hour to 5 days) are offered to parasitic females ofPhanerotoma flavitestacea Fisch., the location where the parasitic egg is deposited, depends on the developmental stage of the host egg at the time of oviposition. When the host egg is 1 hour to 3 days old, the laying takes place in the yolk. On the other hand, if the parasite egg is deposited in a four day old or an older host egg, it is directly laid in the host embryo. According to these results, it seems that the penetration of the parasitic egg or larva is only a passive movement caused by the migration of the yolk into the midgut of the host embryo. These different points and the effect of the sting of the ovipositor on the host embryo, the nature of the elimination of the supernumerary larva, are discussed.相似文献
20.
M. Hayat 《BioControl》1970,15(4):387-399
An account of the Indian forms belonging to the familySigniphoridae is given. The family is represented by two genera namely,Thysanus
Walker andChartocerus
Motschulsky. The genusThysanus with the speciesT. ater
Walker is reported for the first time from India, and is redescribed in greater detail. The subdivision of the genusChartocerus into three subgenera (Chartocerus s. str.,Xana
Kurdjumov, andSigniphorina
Nikol’skaja.) proposed byRosanov (1965) is accepted. In the subgenusXana two new species are described and two already known species are recorded. In the subgenusSigniphorina one new species is described. A new generic character in the subgenital plate of the genusThysanus is proposed. The generic character in the subgenital plate of the genusChartocerus described byMan Mohan (1963) is confirmed.
Résumé La famille desSigniphoridae est représentée par deux genres:Thysanus Walker etChartocerus Motschulsky. Le genreThysanus avec l’espèceT. ater Walker est indiquée pour la première fois de l’Inde et est redécrite avec plus de détails. La subdivision du genreChartocerus en trois sous-genres (Chartocerus s. str.,Xana Kurdjumov etSigniphorina Nikol’skaja proposée parRosanov (1965) est acceptée. Dans le sous-genreXana deux nouvelles espèces (C. (X.) hyalipennis sp. n. etC. (X.) walkeri sp. n.) sont décrites et deux espèces déjà connues sont répertoriée. Parmi celles-ciC. (X.) kurdjumovi (Nikol’skaja) est mentionnée pour la première fois en Inde. Les males de l’espèceC. (X.) kerrichi sont décrits. Dans le sous-genreSigniphorina une nouvelle espèce est décrite.相似文献