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1.
Walter W. Ferguson 《Primates; journal of primatology》1986,27(4):485-492
The taxonPraeanthropus africanus (Weinert, 1950), represented by the Garusi maxilla, is valid and reinstated. The morphological pattern of the Garusi maxilla is not
that of a primitive hominid, but of a relatively generalized pongid. Since the apelike lectotype L.H.-4 and paralectotype
A.L.200-1a ofAustralopithecus afarensis
Johanson et al. 1978 are conspecific withP. africanus, and originate from the same formation, they are reassigned toPraeanthropus africanus. 相似文献
2.
Walter W. Ferguson 《Primates; journal of primatology》1987,28(2):257-265
The subspecies ofAustralopithecus africanus
Dart, 1925 have been revised in a morphological and statistical analysis. Four subspecific names were previously proposed, but
only one was found to be valid. The subspeciesA. africanus transvaalensis (Broom, 1936), from the Plio/Pleistocene of South Africa, cannot be sustained due to an insufficient sample, and is combined with
the nominate race,A. a. africanus. The type ofA. africanus afarensis
Tobias, 1980 is a mistake in identification and notA. africanus, but a pongid. The population ofA. africanus from the late Pliocene of Ethiopia does indeed represent a relatively small-toothed geographical race for which the nameA. africanus aethiopicus was conditionally proposed; and the lectotype for it, A.L. 288-1, is notA. africanus, but the type ofHomo antiquus
Ferguson, 1984. The trinominalaethiopicus is thus unavailable for the Ethiopian race, which is redescribed as a new subspecies,A. africanus miodentatus n. ssp., and the mandible A.L. 266-1 is designated as the holotype. 相似文献
3.
D. Curnoe 《Human Evolution》2001,16(3-4):169-198
Among Plio-Pleistocene hominins the East African ‘robust’ group [Australopithecus (Paranthropus) boisei sensu lato] has the largest sample. This makes it an important test case for examining within-group variability and its implications
for early hominin systematics. When using the CV to test for mixed-species samples, sexual dimorphism and diachronic variation
are important additional (confounding) sources of variability. After examining nineteen variables, five craniometric variables
in the East African ‘robust’ group are identified that have low sexual dimorphism. All are characterised by CVs from a combined
KNM-WT 17000 andA. (P.) boisei sample less than the CV of the bonobo. Diachronic variation is found to be an important source of variability for cranial
capacity. This form of variation cannot be detected in other variables studied here, but its possible presence cannot be ignored
(owing mostly to small sample sizes). It is concluded that there is insufficient evidence to refute the hypothesis that all
East African ‘robust’ fossils belong toA. (P.) boisei (Walker and Leakey, 1988). 相似文献
4.
Walter W. Ferguson 《Primates; journal of primatology》1992,33(2):273-279
In response to a critique byFerguson (1989),Leonard (1991) reiterates most of his original arguments for supporting “Australopithecus afarensis”Johanson, White, andCoppens, 1978 as a single species. He disregards the principle of morphological equivalence by comparing the dental metrics and morphology
of a hominid with those of species of the Pongidae, which do not correspond with the degree of variation in hominids, instead
of with those of species of the Hominidae. He fails to refute clear evidence that the range of variation of dental metrics
and morphology in “A. afarensis” exceeds that seen in species of the Hominidae. On the basis of extreme variation, “A. afarensis” is, therefore, interpreted as representing a composite species. 相似文献
5.
Walter W. Ferguson 《Primates; journal of primatology》1989,30(1):103-109
A fossil skull, Stw 53, from the Plio/Pleistocene of Sterkfontein, in South Africa, has been referred toHomo habilis
Leakey, Napier, andTobias, 1964. Reappraisal of its putative hominine affinity reveals a closer resemblance toAustralopithecus africanus
Dart, 1925. The skull, as reconstructed, is too small forH. habilis; with no indication of brain expansion overA. africanus; has a facial angle outside the hominine range, but identical with that ofA. africanus; and whose teeth are not elongated but display buccolingual expansion. Although it was found in the same strata (Member 5)
as stone tools, there is no causal connection. It has been dated faunistically at 2–1.5 my BP, but due to an unconformity
it is suggested that it could be older. In spite of its late date, Stw 53 shows no intermediate characters which could support
a trend towardsH. habilis orA. robustus
Broom, 1938. It may, therefore, represent a relict population ofA. africanus. 相似文献
6.
J. G. Chmielewski C. C. Chinnappa J. C. Semple 《Plant Systematics and Evolution》1990,169(3-4):151-175
Multivariate analysis of vegetative and reproductive characters was used to examine morphological relatedness amongAntennaria alborosea
A. E. Porsild,A. corymbosa
E. Nels.,A. marginata
Greene,A. microphylla
Rydb.,A. parvifolia
Nutt.,A. rosea
Greene, andA. umbrinella
Rydb. Both pistillate and staminate plants were examined. Some of the characters examined were variable in one species, but stable in another (i.e., presence or absence of papillae on the achenes). Our analyses indicate that the seven species are morphologically distinct. It is hypothesized that theA. rosea agamic complex arose through hybridization amongA. corymbosa, A. microphylla, A. umbrinella, and possiblyA. dioica (L.)Gaertn. However, hybridization between the three former species and others, as well as their subsequent morphological responses to different environmental conditions causes confusion in recognizing the taxa.Antennaria angustifolia
Rydb.,A. arida
E. Nels.,A. confinis
Greene,A. scariosa
E. Nels.,A. foliacea humilis
Rydb.,A. concinna
E. Nels., andA. viscidula
E. Nels. are considered to represent F 1 hybrids. 相似文献
7.
J. G. Chmielewski C. C. Chinnappa J. C. Semple 《Plant Systematics and Evolution》1990,169(3-4):123-150
Patterns of intraspecific variation were examined inAntennaria alborosea
A. E. Porsild,A. corymbosa
E. Nels,A. marginata
Greene,A. microphylla
Rydb.,A. parvifolia
Nutt., andA. umbrinella
Rydb. AlthoughA. alborosea was initially considered arctic in distribution, it became apparent that a southern montane element also exists. Our results suggest that morphological differences between arctic and southern montane specimens represent clinal variation. The additional morphological data for specimens that occur more than 1,500 km south of the species' range as it was initially described result in a better understanding of this once presumed arctic taxon. Morphological variation in the dioecious speciesA. corymbosa, A. marginata, A. microphylla, A. parvifolia, andA. umbrinella was greater between the genders than was geographic variation within each gender. These results demonstrate that both pistillate and staminate specimens must be examined in dioecious species ofAntennaria if morphological variation in the respective species is to be fully understood. Character size or number of broadly distributed species (A. microphylla andA. parvifolia) generally decreased with increasing longitude, whereas characters of species with more restricted distributions (A. alborosea, A. corymbosa, andA. marginata) generally increased in size or number with increasing latitude or longitude.Antennaria umbrinella was an exception in this respect. 相似文献
8.
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
9.
A partial cranium of a juvenile Australopithecus boisei, recovered from the Shungura Formation in the lower Omo basin, southern Ethiopia, and dated at 2.1 m.y. B.P. , is described anatomically and compared to young and adult australopithecines, modern Homo sapiens, chimpanzees, and gorillas. A resemblance to the gracile Australopithecus is observed but is attributed mainly to the generalized appearance of the Omo specimen resulting from its young individual age. An attempt is made to reconstruct part of the ontogenetic process of A. boisei. This process is compared to the developmental changes exhibited by the African great apes and modern man and is found to combine characteristics of both. 相似文献
10.
A cladistic analysis of molecular data from the chloroplast generbcL was used to examine the taxonomic relationships of the walnut family (Juglandaceae). In addition, chemical and morphological data from a previous study byHufford (1992) were incorporated, expanded, and analyzed independently and in combination with the molecular data. The results of these analyses suggest that theJuglandaceae are more closely related to theFagaceae, Betulaceae, Casuarinaceae, andUrticaceae and their relatives (sensuCronquist 1981) than they are to theAnacardiaceae (sensuThorne 1983). However, sequence data fromrbcL also suggest a relationship between the higherHamamelidae and certain families in theRosidae sensuCronquist 1981 (such asRosaceae andRhamnaceae), an outcome which would add credence to the widely accepted view of the polyphyletic nature of theHamamelidae. 相似文献
11.
Hordeum caespitosum
Scribner,H. jubatum L., andH. lechleri (Steudel)Schenck are very similar in appearance and therefore until recently were mostly not recognized as separate entities. The first two are tetraploid and natives to North America, but the second occurs naturally in eastern Siberia and has been introduced in Europe and South America and may become a cosmopolitan weed. The third is hexaploid and South American. This study analyses their morphological diversity by means of selected multivariate techniques in order to determine if there is justification to recognize them as three separate morphological species. Logistic discrimination, although based on a reduced set of characters, yielded the highest percent of correct assignments. A linear discriminant function is provided and validated by 100 bootstrap repeats. Canonical discriminant analysis indicated three groups. It is subsequently concluded that the three are separate morphological species. Although a linear discriminant function is given, a traditional identification key is provided based on the palea length and triad (the group of three spikelets at each rachis node) length. 相似文献
12.
G. Suwa 《Human Evolution》1996,11(3-4):269-282
The early hominid dental remains from the Omo succession represent a fragmentary but important source of information regarding
hominid evolution during the 2 to 3 myr time period. As an initial step toward the evaluation of taxonomic affinities and
evolutionary significance, the present study attempts serial allocations of 21 isolated mandibular molars from the Shungura
and Usno Formations. A comparative sample consisting of 250 mandibular molars ofA.afarensis, A.africanus, A.robustus, A.boisei and earlyHomo was used to compile the baseline data for allocating the isolated Omo molars to serial positions. The methods employed in
the present study include morphometric analyses of 5 cusp areas, 8 linear variables reflecting crown shape, and 4 measurements
of fissure pattern. It was found that by combining morphological observations with both “restricted” and “non-restricted”
applications of discriminant function analyses (sensu Albrecht, 1992), sufficiently reliable serial allocations could be attained. 相似文献
13.
Bogdan Korica 《Plant Systematics and Evolution》1979,133(1-2):71-76
Asperula visianii
Korica is described as a new stenoendemic species from the small Central Dalmatian island of Svetac (near Vis). It differs in several morphological features (which remain constant in cultivation) and in its ecology from the closely relatedA. staliana
Vis., endemic on the nearby island of Bievo. 相似文献
14.
The systematics of the aquatic fern genusAzolla
Lam. is revised at the supraspecific level. Published morphological data are reviewed, and cytological and cladistic analyses of the genus conducted, enabling a discussion of the putative evolutionary trends in the genus, and a revision of the current taxonomy. A phylogenetically more acceptable subgeneric and sectional classification is proposed, viz. subg.Azolla sect.Azolla (comprisingA. filiculoides
Lam.,A. rubra
R. Br.,A caroliniana auct. nonWilld.,A. microphylla auct. nonKaulf. andA. mexicana
Presl), subg.Azolla sect.Rhizosperma (Mey.)Mett. (comprisingA. pinnata
R. Br.), and subg.Tetrasporocarpia subg. nov. (comprisingA. nilotica
Decne. exMett.). 相似文献
15.
Morphological and cytological investigations as well as crossing experiments were carried out withRanunculus seguieri
Vill. and 4 species of theRanunculus alpestris L. group (R. alpestris L.,R. traunfellneri
Hoppe,R. bilobus
Bertol.,R. crenatus
Waldst. & Kit.). ForR. seguieri andR. alpestris, localities and distribution are given in addition to extensive diagnoses. A key to the species includes morphological characteristics and distribution data forR. traunfellneri, R. bilobus, andR. crenatus. New diagnostic characters are described. Crossing experiments betweenR. seguieri and the species of theR. alpestris group were unsuccessful. All 5 species have a chromosome number of 2n = 16, the record forR. bilobus is new. There is no statistically significant difference between the karyotypes ofR. seguieri andR. alpestris s. str. Nevertheless, according to morphological evidence and crossing experiments,R. seguieri is not closely related to theR. alpestris group. 相似文献
16.
In North Africa,Ornithogalum L. subg.Beryllis
Baker is represented by three taxa (O. narbonense L.,O. pyrenaicum L., andO. sessiliflorum
Desf.), often difficult to identify. 90 individuals from 4 localities were subjected to a biometric study based on 19 morphological characteristics. Several types of multivariate analyses allow a perfect identification of the three species. Studies on the reproductive biology, cytotaxonomy, and ecology supplement these data. 相似文献
17.
The phylogenetic relationships of the angiosperm generaByblis andRoridula have been the subject of ongoing taxonomic controversy. Twenty-eight taxa of varying degrees of alleged relationship, including 3 members of theWinteraceae (as an outgroup), were investigated using partial sequences of 18S rRNA (small subunit) and also compared against the morphological data set fromHufford's (1992) cladistic treatment of 80 members of theRosidae-Asteridae. The morphological analysis placed the two genera in a clade with theSarraceniaceae in theCorniflorae-Asterid group as a sister taxon to anEricales-Hydrangeales clade. The 18S rRNA analysis supports the recently publishedrbcL DNA analysis ofAlbert & al. (1992), withRoridula joined to taxa in the lowerRosidae, butByblis joining instead to members of theAsteridae near theSolanaceae. Comparisons for congruence between the three analyses placeByblis in the higher Asterid group near theSolanaceae, andRoridula possibly nearer theSarraceniaceae andEricales. These results imply that the traditional morphological characters used to relate the two genera are possibly the result of convergence towards similar ecological and life-history strategies rather than synapomorphies. 相似文献
18.
Intergeneric crosses were made between representatives of the genomically-defined generaElymus, Agropyron, Elytrigia, Pseudoroegneria, andThinopyrum. The genomic constitution ofElytrigia repens, the type species ofElytrigia, is shown to be SSH, a genomic combination otherwise found only inElymus. The S genome ofPseudoroegneria has almost always a dominant influence on the morphology of the taxa of which it is a component.Wang (1989) showed that the J genome inThinopyrum and the S genome have considerable homoeology, with a mean c-value of 0.35 in diploid SJ hybrids. A genetic coherence from S to SJe, Je, JeJb, and Jb can be expected, agreeing with the continuous morphologic variation pattern observed. Because of the absence of morphological discontinuities between the taxa,Pseudoroegneria (S),Elymus (SH, SY, sometimes with additional genomes),Elytrigia (SSH, SSHX), andThinopyrum (SJ, SJJ, J) are best treated as a single genus,Elymus, following the generic concept ofMelderis in Flora Europaea and Flora of Turkey. The basic genomic constituents ofElymus will then be the S and/or J genomes.Agropyron, with diploids, tetraploids, and hexaploids based on the P genome is morphologically distinct from other genera inTriticeae. In a few species ofElymus andPseudoroegneria, a P genome is an additional constituent. In these cases the P genome has a negligible morphological influence. Therefore, it seems reasonable to maintainAgropyron as a separate genus. 相似文献
19.
The dimension and variation range of terminal and intercalary cells, heterocysts, and akinetes of fourAphanizomenon taxa occurring in Czechoslovakia were studied. Statistical and graphical procedures were used for evaluation. With regard toA. flos-aquae, the results support the distinction of two varieties (var.flos-aquae and var.klebahnii). In the samples determined asA. gracile two clearly distinguishable morphological types could be found; one of them is recognized as a new species:A. flexuosum. Its diacritical features are established and problems of the intrageneric taxonomy ofAphanizomenon and its demarcation from the genusAnabaena are discussed.Dedicated to Prof. DrLothar Geitler on the occasion of his 90th birthday. 相似文献
20.