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1.
Analysis of flotation samples from twelve sites in Karnataka and Andhra Pradesh (south India) provides clear evidence for the predominant subsistence plants of the Neolithic period (2,800–1,200 cal b.c.). This evidence indicates that the likely staples were two pulses (Vigna radiata and Macrotyloma uniflorum) and two millet-grasses (Brachiaria ramosa and Setaria verticillata) which were indigenous to the Indian peninsula. At some sites there is evidence for limited cultivation of wheats (Triticum diococcum, Triticum durum/aestivum) and barley (Hordeum vulgare), and a few crops that originated in Africa, including hyacinth bean (Lablab purpureus), pearl millet (Pennisetum glaucum) and finger millet (Eleusine coracana). In addition there is evidence for cotton (Gossypium sp.), and linseed (Linum sp.), as well as gathered fruits of Ziziphus and two Cucurbitaceae. This evidence suggests that the earliest agriculture in south India, dating to the third millennium b.c., was based on plants domesticated in the region, and that subsequently from the late 3rd millennium b.c. through the 2nd millennium additional crops from other regions were adopted into the subsistence system.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00334-004-0036-9  相似文献   

2.
Field observations on pollination in New World species of the genusSarcostemma R. Br. sensuHolm are reported. Morphological and anatomical comparisons of pollinated flowers ofSarcostemma subg.Ceramanthus Kuntze (New World) andSarcostemma subg.Sarcostemma (Old World) are presented.  相似文献   

3.
The past decade has brought considerable debate on the subject of modern human origins. The nature of the transition from Homo erectus to archaic Homo sapiens to modern H. sapiens has been examined primarily in terms of the relative contribution of archaic populations to later moderns, both within and among geographic regions. The recent African origin model proposes that modern humans appeared first in Africa between 100,000 and 200,000 years ago, and then spread through the rest of the Old World, replacing preexisting populations.1–6 This model has been referred to by a variety of names, including “replacement”, “Garden of Eden”, “Noah's Ark”, and “out of Africa”. The recent African origin model contrasts with the multiregional model, which proposes a species-wide transition to modern humans throughout the Old World during the past million years or more.7–10 Indeed, some proponents of the multiregional model advocate placing Homo erectus and all subsequent species of Homo in the evolutionary species Homo sapiens.11 This contrasts with the view that there were multiple hominid species during the Middle Pleistocene. The debate continues.12,13 Although the multiregional model is often portrayed as proposing a simultaneous transition to anatomically modern humans in different geographic regions, it explicitly allows for varying degrees of continuity across time and space.10 This model, in the broad sense, does not rule out the possibility that modern human morphology appeared first in Africa and then spread through the rest of the Old World through gene flow. However, not all advocates of the multiregional model adhere to this specific subset of the general model.9 Comparison of the African and multiregional models is complicated by considering other, less extreme, hypotheses. Some versions of the recent African origin model imply a speciation event associated with the initial origin of modern humans. Another version, which suggests the possibility of some admixture between “moderns” leaving Africa and preexisting “archaics” elsewhere in the Old World,14,15 is similar to some variants of the multiregional model, which also suggest that modern morphology appeared first in Africa, but involved admixture with other Old World populations.16 The major difference between these views appears to be the extent of admixture, although the exact level is never specified. A further complication is the possibility that multiple dispersals from Africa produced a more complicated pattern of worldwide variation.17  相似文献   

4.
T’ef ( Eragrostis tef ) in Ancient Agricultural Systems of Highland Ethiopia. T’ef (Eragrostis tef) has been cultivated in the Horn of Africa for at least 2,000 years. The earliest known agricultural systems in this region date to the Pre-Aksumite period (800–400 b.c.) and appear to have focused on Near Eastern crops, with indigenous African species increasing in importance during Aksumite times (400 b.c.a.d. 700). While palaeoethnobotanical data are available from Pre-Aksumite and late Aksumite periods, macroscopic botanical remains from the site of Ona Nagast, northern Ethiopia, provide a first glimpse of agricultural systems dating to Proto-Aksumite (400–50 b.c.), Early to Classic (50 b.c.a.d. 340), and Post-Aksumite (a.d. 700–900) times. Archaeological t’ef remains from Ona Nagast are examined in detail. Guidelines are developed for the identification of t’ef grains preserved on archaeological sites, with a focus on how to differentiate them from seeds of wild Eragrostis species. Charring experiments reveal that in some cases t’ef may not survive high temperatures tolerated by larger cereal grains, such as wheat and barley. The domestication history of t’ef appears to be different from some other cereals, a factor which may explain the preponderance of indeterminate Eragrostis seeds in archaeological samples. Selection of large seed size and intensified tillage were not key factors in t’ef domestication. Early cultivators were likely selecting for increased branching and higher percentage seed set under conditions of minimal tillage.  相似文献   

5.
The genus Gardenia (Rubiaceae), noted for its beautiful and fragrant flowers, is widespread throughout the Old World tropics. In the Fijian Region it is represented by eleven indigenous species, of which eight are endemic to Fiji; an additional oriental species is occasionally found in cultivation. The taxonomic relationships and nomenclature of these species are discussed, and one new Fijian species, G. anapetes, is described.  相似文献   

6.
Growth data from a number of species of Old and New World primates have been analyzed by calculating instantaneous relative growth rates. Species discussed are the New World species Saimiri sciureus and Saguinus nigricollis, and the Old World species Pan troglodytes and Macaca mulatta. The analysis of the perinatal growth data indicated that differences in relative growth rates are present during early periods of growth. More specifically, it was found that the closer taxonomically a species is to man the greater the deceleration of growth during the first postnatal year. It is suggested that this may be a general primate trend.  相似文献   

7.

The Historia Naturalis Brasiliae (HNB, 1648) is the most complete treatise on Brazilian flora and fauna created in the seventeenth century. Scientists Marcgrave and Piso depicted hundreds of plants and described uses, vernacular names, and diseases in Dutch Brazil. We aimed to verify whether these plants are still used similarly, using herbarium vouchers and taxonomic literature to identify the species described in the HNB and reviewing historical and modern ethnobotanical literature to analyze whether the HNB documented specific plants and uses for the northeast region. We highlighted Old World species, as they indicate plant introduction before and during the trans-Atlantic slave trade and exchange of African ethnobotanical knowledge. Of the 378 species found in the HNB, 256 (68%) were useful, mostly used for healing and food in a similar way (80%) both in the seventeenth century and in modern Brazil. Only one species (Swartzia pickelii) is endemic to northeast Brazil, while the others are more widely distributed. The HNB includes one of the first reports on African crops in Brazil, such as sesame, okra, and spider plant. This study brings insights on indigenous and African plant knowledge retentions since the creation of the HNB and acknowledges its non-European contributors.

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8.
The chromosome complement in the human bed bug, Cimex lectularius Linn., is 26+X1X2Y in the male and 26+X1X1X2X2 in the female. However, a population from Cairo, Egypt has 4 supernumerary X chromosomes. In the hybrid between the Berkeley population (with no supernumeraries) and the Cairo population (with 4 supernumeraries), the behavior of supernumeraries was observed during embryogenesis and oogenesis as well as spermatogenesis.In embryogenesis the transmission of supernumeraries was quite regular. However, one chromosome may sometimes be eliminated early in the germ line. This abnormality could induce the variations in chromosome number encountered in later stages. In the first meiotic division, some of the supernumeraries were nondisjunctional. Moreover, in the second division, some supernumeraries were eliminated. These results show that there is a tendency towards a decrease in the number of supernumeraries in the hybrids.Although the supernumeraries behave like X chromosomes, they seem not to be important for sex determination and appear to be largely or entirely inert genetically. Supernumeraries in the bed bug originate from small fragments caused by structural rearrangement. They are increased by an accumulation mechanism. Supernumeraries in the bed bug appear to be of relatively recent origin. The phylogenetic sequence in their development was probably from none to a stabilized number of four in the Old World. Then the supernumeraries were lost in two specialized lines, Cimex columbarius Jenyns on domestic birds in Europe and Cimex lectularius Linn. on man in the Western Hemisphere.This study was carried out under U.S. Public Health Service Grant (GM-13197).  相似文献   

9.
Drosophila subobscura is a Palearctic species that was first detected in the New World in Puerto Montt (Chile) in February 1978. Since that time, it has spread over a broad area and increased in population density. The South American populations exhibit a high level of chromosomal polymorphism: 20 different arrangements exist, distributed among five chromosomes. Chromosomal arrangement heterozygosity varies from 0.55 to 0.61 in the nine populations examined. Incipient clines in the frequencies of the arrangements are appearing; these clines follow the same latitudinal direction as in the Old World. Wing length significantly decreases with latitude, as it does in Europe. The colonization of South America by D. subobscura appears to be a major natural experiment with outcomes that duplicate the distributional patterns—in chromosomal polymorphism and in wing length—observed in the Old World, thereby strongly supporting the adaptive significance of these patterns. The data show a very rapid effect of natural selection promoting genetic differentiation among natural populations.  相似文献   

10.
11.
Fruits, seeds and embryos of Pimenta officinalis Lindl. syn. Pimenta dioica (L.) Merr. (Myrtaceae) have been found in Gdask (northern Poland) in latrines dated to the 18th century. This is one of the first few records of allspice from European archaeobotanical material. The paper presents morphological criteria used for the identification of allspice or myrtle pepper remains and briefly summarises the information on the introduction of this species to the Old World.  相似文献   

12.
In this paper, the auther re-examinesKloeckera faecalis Batista &Silveria 1959 and transfers to genusPichia.
Resumen El autor hace una revisión de la levaduraKloeckera faecalis llevandola al géneroPichia.
  相似文献   

13.
Based on personal collections ofGlobba unifolia Ridl. andG. unifolia var.sessiliflora Holtt., the latter is recognized as a distinct species. As the nameG. sessiliflora is already occupied, the nomen novumG. corneri is proposed in honour of Prof. DrE. J. H. Corner, who was the first collector of the plant.Dedicated to Prof. DrE. J. H. Corner (Cambridge) on the occasion of his 85th birthday on January 12th, 1991.  相似文献   

14.
Macrofossil data from 73 sites dating to the south Swedish Iron Age (500 b.c.a.d. 1100) have been compiled and analyzed in order to elucidate long term changes in cereal cultivation. The analyses indicate that “permanent field” agriculture was established at the end of the Bronze Age utilizing Hordeum vulgare var vulgare as a primary crop and Triticum aestivum ssp vulgare/compactum, Triticum spelta/dicoccum/monococcum, Avena sativa and Secale cereale as secondary crops. An observed change towards the end of Roman Iron Age (1–a.d. 400) is the expansion of Secale cereale and Avena sativa cultivation. Evidence also suggests that winter sowing of the former commenced at the latest during the eighth, ninth and tenth centuries a.d. The introduction of winter sowing possibly coincided with the establishment of crop rotation agriculture. During most of the Iron Age southern Sweden displays significant regional variations with regards to cereal cultivation practice. There is however evidence that a more homogenous agriculture appeared across the investigated area from the beginning of the Viking Age (a.d. 800–1100) onwards.  相似文献   

15.
Datura (Solanaceae) is a small genus of plants that, for long, was thought to occur naturally in both the New and Old Worlds. However, recent studies indicate that all species in the genus originated in the Americas. This finding has prompted the conclusion that no species of Datura could have been present in the Old World prior to its introduction there by Europeans in the early 16th century CE. Further, the textual evidence traditionally cited in support of a pre-Columbian Old World presence of Datura species is suggested to be due to the misreading of classical Greek and Arabic sources. As a result, botanists generally accept the opinion that Datura species were transferred into the Old World in the post-Columbian period. While the taxonomic and geographic evidence for a New World origin for all the Datura species appears to be well supported, the assertion that Datura species were not known in the Old World prior to the 16th century is based on a limited examination of the pre-Columbian non-Anglo sources. We draw on old Arabic and Indic1 texts and southern Indian iconographic representations to show that there is conclusive evidence for the pre-Columbian presence of at least one species of Datura in the Old World. Given the systematic evidence for a New World origin of the genus, the most plausible explanation for this presence is a relatively recent but pre-Columbian (probably first millennium CE) transfer of at least one Datura species, D. metel, into the Old World. Because D. metel is a domesticated species with a disjunct distribution, this might represent an instance of human-mediated transport from the New World to the Old World, as in the case of the sweet potato (Ipomoea batatas).  相似文献   

16.
Two novel, non-glaucofide, germacrolide sesquiterpene lactones, 8α-methacryloyloxycostunolide-1(10),4(5)-diepoxide and 1-oxo-10α-OH-8α-methacryloyloxycostunolide (not fully characterized), were isolated from Vernonia jonesii and the previously described glaucolide B was identified from V. pooleae. This is one of the few reports of non-glaucolide type germacrolides in a New World species of Vernonia, although members of this class of sesquiterpene lactones are common constituents of Old World species of the genus. The chemical evidence supports the suggestion that V. jonesii may be part of a relictual, isolated group of the New World Vernonia, closely related to some of the Old World taxa.  相似文献   

17.
Evidence for Gondwanan vicariance in an ancient clade of gecko lizards   总被引:2,自引:0,他引:2  
Aim Geckos (Reptilia: Squamata), due to their great age and global distribution, are excellent candidates to test hypotheses of Gondwanan vicariance against post‐Gondwanan dispersal. Our aims are: to generate a phylogeny of the sphaerodactyl geckos and their closest relatives; evaluate previous phylogenetic hypotheses of the sphaerodactyl geckos with regard to the other major gecko lineages; and to use divergence date estimates to inform a biogeographical scenario regarding Gondwanan relationships and assess the roles of vicariance and dispersal in shaping the current distributions of the New World sphaerodactyl geckos and their closest Old World relatives. Location Africa, Asia, Europe, South America, Atlantic Ocean. Methods We used parsimony and partitioned Bayesian methods to analyse data from five nuclear genes to generate a phylogeny for the New World sphaerodactyl geckos and their close Old World relatives. We used dispersal–vicariance analysis to determine ancestral area relationships among clades, and divergence times were estimated from the phylogeny using nonparametric rate smoothing. Results We recovered a monophyletic group containing the New World sphaerodactyl genera, Coleodactylus, Gonatodes, Lepidoblepharis, Pseudogonatodes and Sphaerodactylus, and the Old World Gekkotan genera Aristelliger, Euleptes, Quedenfeldtia, Pristurus, Saurodactylus and Teratoscincus. The dispersal–vicariance analysis indicated that the ancestral area for this clade was North Africa and surrounding regions. The divergence between the New World spaherodactyl geckos and their closest Old World relative was estimated to have occurred c. 96 Myr bp . Main conclusions Here we provide the first molecular genetic phylogenetic hypothesis of the New World sphaerodactyl geckos and their closest Old World relatives. A combination of divergence date estimates and dispersal–vicariance analysis informed a biogeographical scenario indicating that the split between the sphaerodactyl geckos and their African relatives coincided with the Africa/South America split and the opening of the Atlantic Ocean. We resurrect the family name Sphaerodactylidae to represent the expanded sphaerodactyl clade.  相似文献   

18.
Effects of hybridization on sesquiterpene lactones in Xanthium strumarium were studied for clues to the relationship of Old and New World populations. In crosses between indigenous Asiatic plants in the “strumarium” morphological complex and various American complexes that produce xanthinin as a major sesquiterpene lactone, the F1 hybrids contained xanthinin and the related compounds, xanthanol, xanthatin, and xanthinosin. In other crosses with various American complexes that produce xanthumin, the stereoisomer of xanthinin, the F1 hybrids contained xanthinin and xanthumin as well as xanthinin-related compounds and their stereoisomers, xanthumanol, deacetoxylxanthumin, and tomentosin. The Asiatic plants of “strumarium” from Hong Kong involved in the crosses produce approximately equal percentages of xanthinin, xanthatin and xanthinosin, but those from India contain only xanthinosin. The putative introduction of the American morphological complex, “chinense,” contains xanthumin as the major component but shows chemical diversity that indicates genes derived from the indigenous “strumarium” complex.  相似文献   

19.
In this paper, the author re-examinesKloeckera faecalis Bat. &Sil. 1959 and transfers to genusPichia.
Resume El autor hace una revisión de la levaduraKloeckera faecalis llevàndola al géneroPichia.
  相似文献   

20.
Patterns of fire occurrence within the Las Bayas Forestry Reserve, Mexico are analyzed in relation to variability in climate, topography, and human land-use. Significantly more fires with shorter fire return intervals occurred from 1900 to 1950 than from 1950 to 2001. However, the frequency of widespread fire years (25% filter) was unchanged over time, as widespread fires were synchronized by climatic extremes. Widespread fire years occurred during dry years that lagged wet years. Widespread fire years lagged the negative El Niño phase (wet winters) of the Southern Oscillation by 1 year, but were not synchronized by the positive, La Niña phase (dry winters) of the Southern Oscillation. The smaller, localized fires that occurred more frequently during the first half of the 20th century were attributed to changes in land tenure with the introduction of the ejido system in the early 1950s. Ejido management strategies lowered fire frequencies by suppressing fires and reducing anthropogenic fires. There were likely more ignitions prior to the arrival of the ejido system as fires were ignited by lightning and indigenous people. As the movement of indigenous peoples across the landscape has been restricted by changes in land tenure, numbers of human-ignited fires subsequently decreased post 1950. After 1950, fires occurred less frequently, were more synchronized, and more restricted to years of extreme climate.  相似文献   

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