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1.
Macchiarelli & Bondioli (1984, 1986) argue that post-Pleistocene cranio-facial reduction cannot be explained by biomechanical factors related to
change in the diet (Carlson, 1974;Carlson & Van Gerven, 1977) or to facial reduction related to the selective advantages of smaller, morphologically simpler teeth (Greene, 1967;Van Gerven, Armelagos & Rohr, 1977). Instead, they maintain that facial reduction is a mere side-effect of a reduction in overall body size. Our analysis
of skeletal and facial reduction in post-Pleistocene Sudanese Nubia suggests thatMacchiarelli & Bondioli's interpretation is incorrect for two reasons. First, the reduction in facial morphology (at least since Mesolithic times)
is greater by several orders of magnitude than the reduction in general body size. Second, the dentition not only shows a
greater size reduction than does general body size, but a shifting pattern of dental reduction rather than a general decrease
across all teeth. 相似文献
2.
M. K. Macphail A. D. Partridge E. M. Truswell 《Plant Systematics and Evolution》1999,214(1-4):199-210
Microfossils which matchLactoris (Lactoridaceae) pollen more closely than those of any other living angiosperm occur in Campanian to Paleogene sediments around the margins of Australia. These are referred to the fossil genus Lactoripollenites (Zavada & Benson 1987). A species belonging to the same genus occurs in older (Turonian-Santonian) deposits off southern Africa but Australian specimens represent not only the most southern, but also the youngest known (Oligocene) records to date. Our data support suggestions that theLactoridaceae were widespread across the Southern Hemisphere during the Late Cretaceous (Lammers & al. 1986,Zavada & Benson 1987). An homology between gymnosperm sacci and the saccus-like structures found in Lactoripollenites and some specimens ofLactoris pollen is contested, as is the use of (anasulcate) apertures to support the primitive position of the family. 相似文献
3.
Rebecca S. Overbury Luis L. Cabo Dennis C. Dirkmaat Steven A. Symes 《American journal of physical anthropology》2009,139(2):261-268
Studies of skeletal development frequently document populational incidences of bilateral asymmetry. Degenerative morphological skeletal changes, attributed to age related and irregular ossification, may also progress asymmetrically, either as the result of asymmetric biomechanical factors expressed over the lifespan, asymmetric expression of physiological processes, or progressive magnification of asymmetry acquired previously during development. This study illustrates the effects of bilateral asymmetry on age at death estimates obtained from human skeletal remains. The Suchey‐Brooks method, which uses the pubic symphyseal face for age estimation (Katz and Suchey, Am J Phys Anthropol 69 1986 427–435), was selected for the study based on its widespread use. Asymmetry in the Suchey‐Brooks symphyseal age phases was found in over 60% of a sample composed of 20th century White male individuals from 18 to 86 years of age (N = 130). However, results suggest that the presence of asymmetry does not compromise the accuracy of the Suchey‐Brooks method if the morphologically older symphyseal face of an asymmetric individual is used to estimate age at death. In addition, weak directional asymmetry and a correlation between age and asymmetry were found. This suggests that a comparison of asymmetry in this area with that in other skeletal areas, where the factors originating and influencing asymmetry are better understood, may be useful in better understanding the biological processes which underlie the age markers used in the Suchey‐Brooks method. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc. 相似文献
4.
Enigmagraptus n. gen. comprises a group of the smallest known graptolites, with problematical evolutionary ancestors. The species described,
all of Přídolí age are:E. yassensis (Rickards &Wright, 1999),E. cf.yassensis, E. mitchelli (Rickards &Wright, 1999) andE. pennyae n. sp.
相似文献
5.
The somatic nuclear division ofChaetomium globosum was studied utilizing acetocarmin and aceto-orcein techniques. Nuclear division in hyphae of this species was found to be mitotic, but diversity in morphology and division configuration was noted. Identifiable chromosomes, the metaphase plate, and the chromosome bridge were commonly seen.A combination of extremely small nuclei, difficulties in staining, multinucleate conditions, and protoplasmic streaming in hyphae presented difficulties for these studies. Contradictory views are held on the structure of the nucleus, presence of the centriolar body, and other karyological features as described byFinley (1970)Rabinow &Bakerspigel (1965). Nuclear division structural details in a few other fungal species such as the centriolar body, spindle apparatus, and nuclear membrane disassociation have been examined by electron microscopy (Motta, 1969;Ichida &Fuller, 1968;Namboodiri &Lowry, 1967).The present study and the previous report onC. globosum (Hsu, Yu &Volz, 1972) presents comparative data for a NASA Appollo 16 MEED Mycology investigation now in progress. 相似文献
6.
Immunogens were found associated with particular fractions prepared from spherules ofCoccidioides immitis (Kong, Levine &Smith, 1963) and from yeast cells ofHistoplasma capsulatum (Salvin &Ribi, 1955). However,Blastomyces dermatitidis, another dimorphic systemic fungal pathogen was shown to elicit a minimal immunogenic response in experimental animals (Kong &Levine, 1967). It was therefore deemed pertinent to study factors which might enhance the resistance of mice to infection withB. dermatitidis. 相似文献
7.
Summary It is suggested that the construction of molecular models of the chromosome may prove to be a fruitful way of attacking the fundamental problems of cytology and genetics. Certain micelles consisting of molecules of protamine-nucleate are suggested for consideration. They are designed to interpret in molecular terms the postulates of genetics and the nature of the gene, and are constructed with special reference to the findings of the cytologists as to the capacity of the chromosomes to swell, to contract, to grow and to divide.Based upon a lecture given in the physics department of the University of Manchester on May 13, 1935. The Author is indebted to W. T.Astbuby, L. E.Bayliss, J. D.Bernal, D.Crowfoot, C.D.Darlington, P.& G.Eggleton, J.M.Gulland, L.J.Harris, D.Jordan Lloyd, M. F.Howson, W. O.Kermack, E. H.Neville, M.Polanyi and J. Z.Young for advice and criticism. 相似文献
8.
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
9.
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
10.
Paul A. Volz 《Mycopathologia》1972,48(2-3):175-185
The purpose of this study is to determine the ability of select Agaricales species to utilize various sources of carbon, nitrogen, vitamins, and growth hormones. Fungi selected for the studies include:Cantharellus clavatus
Fries,C. cibarius
Fries,Lepista nuda (Bull. ex. Fries)Cooke,Pleurotus ostreatus (Jacq. ex. Fries)Kummer, andVolvariella volvacea (Bull. ex. Fries)Singer. Three strains ofC. cibarius and one mutant ofV. volvacea (V135), V134, were employed to determine if nutritional requirement differences occurred. One species,V. volvacea, is grown commercially as a cottage industry in the Orient (Alicbusan &Ela, 1961) while the other species currently have no commercial value. All species studied possess pleasing flavors and have potential use in the mushroom production industry.A literature compilation of the nutritional regulation of basidiocarp formation and vegetative growth of Agaricales was made with specific mention to the named species (Volz &Beneke, 1969). Recent nutritional studies with one or more of the specific species include those byYusef &Allam (1967), andEger (1970). 相似文献
11.
Mario Benazzi 《Chromosoma》1966,19(1):14-27
The problem of the sexual differentiation of the neoblasts of planarians is approached on the basis of karyological evidence assembled by the author and by his collaborators. In the polyploid and pseudogamic biotypes of Dugesia benazzii, D. lugubris and Polycelis nigra, the transformation of the neoblasts into oogonia or spermatogonia is accompanied by variations in the chromosome set. These variations may be considered to be dependent upon the gradient of sexuality — that is, of the territorial influences that determine the evolution in a female or a male direction. Significant evidence is also inferred from the chromosome cycle of hybrids between amphigonic diploid biotypes and polyploid biotypes. A new direction of research, based on the comparison between anterior and posterior regenerated segments of experimental polyploids with variable chromosome sets aims at establishing possible regional differences in the set of the neoblasts.Dedicated to Prof. Dr. J. Seiler on the occasion of his eightieth birthday. 相似文献
12.
Summary The frequency of partial heterozygotes was measured at different points of the T4 chromosome, using am- and rII-mutants. Two to three times more heterozygotes were formed in gene 34 and in gene 25 than in the rII-region or gene 23 resp. This finding is interpreted to be a consequence of increased recombination frequency in certain regions of the T4 DNA-molecule, in agreement with two other, independent sets of data (Womack, 1965; Mosig, 1966). 相似文献
13.
Summary This paper deals with some interesting new fungi which are described as a contribution for the development of the Mycogeography.Arbuscula
Batista &Peres n. gen. is studied as a member of the family Stilbaceae havingA. eugeniae
Batista &Peres n. sp. on leaves ofEugenia jambolana
Lam. from Lucknow, India, as the type species. Another new genus isEllisia
Batista &Peres, typified byE. ingae
Batista &Peres n. sp. on leaves ofInga fagifolia (L.)Willd. from Manaus. Amazonas, Brazil. Two new binomia are:Eriomycopsis paraensis
Batista &Peres n. sp. on leaves ofBertholletia excelsa H.B.K. from Belem, State of Pará, Brazil,Sporidesmium americanense
Batista &Peres n. sp. on leaves ofQuercus wislizenii A.D.C., from U.S.A. andSporidesmium cookei (Hughes)W. B. Ellis, on leaves of Lauraceae, from Manaus.
Dedicado à Mrmória do Prof.Raffaele Ciferri 相似文献
Zusammenfassung Diese Arbeit bringt einige interessante neue Pilze, welche als Beitrag zur Entwicklung der Mycogeographie beschrieben werden.Arbuscula Batista &Peres n. gen. wurde studiert als ein Mitglied der Familie Stilbaceae, dessen TypusA. eugeniae Batista &Peres n. sp. sich auf Blättern vonEugenia jambolana Lam. aus Lucknow, Indien, befand. Eine andere neue Gattung istEllisia Batista &Peres, typiziert durchE. ingae Batista &Peres n. sp. auf Blättern vonInga fagifolia (L.)Willd. aus Manaus, Amazonas, Brasilien. Zwei neue Binome sind:Eriomycopsis paraensis Batista &Peres n. sp. auf Blättern vonBertholletia excelsa H.B.K. aus Belém, Staat Pará, Brasilien,Sporidesmium americanense Batista &Peres n. sp. auf Blättern vonQuercus wislizenii A.D.C. aus U.S.A. undSporidesmium cookei (Hughes)W. B. Ellis, auf Blättern von Lauraceae, aus Manaus, Amazonas.
Dedicado à Mrmória do Prof.Raffaele Ciferri 相似文献
14.
In a previous paper (Hodkinson &Hunter, 1970a) we reported that salmon, suffering from a disease called ulcerative dermal necrosis, appeared to have precipitating antibodies to the mycelium of a fungus associated with their diseased skin lesions. This was confirmed when antigens were prepared from pure cultures of the fungus, a species ofSaprolegnia (Hodkinson &Hunter, 1970b). In this paper we describe the effects of culture media on the antigenicity ofSaprolegnia mycelium, as detected by double gel diffusion with salmon sera. 相似文献
15.
Gottfried Hohmann 《Primates; journal of primatology》2001,42(1):91-99
This study reports on close spatial association and repeated behavioural interactions between two strange adult male bonobos
with residents of another community. Over a period of 12 months one of the two males developed friendly social relations to
some of the females and other residents, which were indistinguishable from those existing between co-residents. Aggression
by resident males against the strangers decreased but the former remained intolerant. The strange males appeared at a time
when the number of adult resident males was lower as in the years before and when the adult sex ratio (number of adult females
per male) was higher as in the years before. Using definitions from studies on dispersal patterns of male gorillas (Harcourt, 1978) and female bonobos (Furuichi, 1989) the spatial association between the two strange males and residents could be described as male transfer. 相似文献
16.
Pablo E. Puertas Rolando Aquino Filomeno Encarnacion 《Primates; journal of primatology》1995,36(2):281-287
In studies performed during 1986, 1987, 1990, and 1991, in the seasonally flooded forest of the Napo and Nanay river basin,
we recorded seven instances of cohabitation in night monkeys,Aotus vociferans. Cohabitation refers to the sharing of a sleeping site of one species of animal with other different species of animals (Aquino & Encarnacion, 1986). We also recorded two instances of cooccupation of night monkeys with other species of nocturnal mammals. Cooccupation
refers to the independent use of different sleeping sites within the same tree by two or more species of animals. This study
is the first report of cooccupation within the generaAotus. Forty-five sleeping trees with entrance holes were used by the night monkeys. In addition, one sleeping site was observed
in a small concavity of the foliar sheath on aMauritia flexuosa palm. 相似文献
17.
Hartmut H. Hilger Mechtild Balzer Wolfgang Frey Dieter Podlech 《Plant Systematics and Evolution》1985,148(3-4):291-312
Microparacaryum (M. Pop. exH. Riedl)Hilger & Podlech is described as a new genus of theBoraginaceae-Cynoglosseae. It comprises the annual species hitherto included inParacaryum (DC.)Boiss. andMattiastrum (Boiss.)Brand. Distribution maps are given for all 3 genera.Microparacaryum consists of two species,M. salsum (Boiss.)Hilger & Podlech (M. s.) andM. intermedium (Fresen.)Hilger & Podlech (M. i.). ParticularlyM. i. is a very variable species, and most of the species formerly recognized belong here. Scattered all over the range of the genus, plants occur with nutlets exhibiting flat or incurved marginal wings, often in mixed populations. This fruit polymorphism is taxonomically treated by recognizing formae. In addition, the following new infraspecific taxa and combinations are described:M. i. var.intermedium formaparacaryoides
Hilger & Podlech,M. i. var.stellatum (H. Riedl)Hilger & Podlech,M. i. var.stellatum formamattiastroides
Hilger & Podlech,M. s. formamattiastroides
Hilger & Podlech. 相似文献
18.
Renato D'Ovidio Giuseppe Scarascia Mugnozza Oronzo A. Tanzarella 《Plant Systematics and Evolution》1990,173(3-4):187-196
The tandemly repeated multigene families encoding 18S and 25S rRNAs were studied at the restriction enzyme level inPopulus alba L.,Populus deltoides
Bartr. exMarsh.,Populus trichocarpa
Torr. & Gray and in the hybrids between the last two mentioned species. The analysis of single and double digestion with EcoRI, BamHI, XbaI, and SstI endonucleases showed the presence of single repetitive unit types of 12.25 and 11.75kb inP. alba andP. trichocarpa, respectively.P. deltoides showed two rDNA gene types having the same length (12.25Kb) but different nucleotide sequence in the IGS. The rDNAs genes ofP. deltoides andP. triochocarpa are inherited codominantly in their hybrids. 相似文献
19.
Interspecific hybridizations were made between species of theE. semicostatus group, viz.,E. semicostatus (Nees exSteud.)Meld.,E. validus (Meld.)B. Salomon,E. abolinii (Drob.)Tzvel., andE. fedtschenkoi
Tzvel., and species of theE. tibeticus group, viz.,E. pendulinus (Nevski)Tzvel.,E. tibeticus (Meld.)Singh,E. shandongensis
B. Salomon, andE. gmelinii (Ledeb.)Tzvel., as well as among species within theE. tibeticus group. All species are tetraploid (2n = 4x = 28) and possess SY genomes. Meiotic pairing data from 24 hybrids involving 17 interspecific combinations are presented. The average number of chiasmata per cell ranged from 17.91 to 26.20 in hybrids within theE. tibeticus group, compared with 7.26 to 22.04 in hybrids between the two species groups. Despite the extensive collection of cytological data, there was no definite evidence for confirming or disproving the separate existence of the two groups. 相似文献
20.
In an effort to obtain orange mutants ofBlastocladiella emersonii
Cantino &Hyatt, wild type zoospores were treated with mitomycin. From the variants produced, we obtained a stable, albino mutant (Ma-1) that differs significantly from another, previously described (Shaw &Cantino, 1969) UV-induced, albino variant. This report concerns the origin of Ma-1, its distinguishing features, and its apparent similarity to the few LC (late colorless) plants that normally appear in wild type populations. A preliminary note regarding mitomycin-induced variants ofB. emersonii has been published (Matsumae &Cantino, 1970). 相似文献