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1.
J. Liska 《Human Evolution》1987,2(3):205-212
This paper summarizes and applies a continuum of «arbitrariness» or «symbolicity» composed of symptoms, rituals and symbols to the results of research in which American Sign Language (ASL) was used as the method of «language» training. Additionally, an expansion of the symbolicity continuum to include a continuum of «abstractness» with the «conceptual symbol» anchoring the most arbitrary end of the continuum was advanced. The results of the comparison provide additional support for the claim that apes are capable of learning and using symbolic signs. However, only a small number of those symbolic signs could be considered «conceptual symbols».  相似文献   

2.
The purpose of this report is to present data about two !Kung Bushmen! population («Cassequeles» and «Mucuancalas»), inhabiting savannah country, in order to check the existence of significant differences between them and to see if these are imputable to environmental factors.  相似文献   

3.
InCallithrix, Saguinus, Aotus, andCallicebus other group members than the mother participate in infant care. Differences among these species are obvious in respect to the time of being off any caregiver, and in respect to the carrying position (Aotus andCallicebus). Alloparental care, a basic behaviour pattern in these species, has evolved from the parking behaviour of the prosimians. The infants are «parked» at other group members.  相似文献   

4.
K. Stanger 《Human Evolution》1989,4(2-3):181-185
Vocalizations and corresponding behavior patterns were recorded inGalago demidovii (Lorisidae), Microcebus murinus, andCheirogaleus medius (Cheirogaleidae). Physical characteristics of the calls were analyzed and calls correlated with their behavioral context. Based on these correlations an «advertisement» call can be identified in all three species. Interspecific comparison suggest that within the Prosimian suborder there are at least two different evolutionary pathways in the organization of this call and of the vocal repertoires in general. The Lorisid speciesG. demidovii conveys acoustic information mainly in pulsed calls, leading to an extreme amplitude-modulation. Individual characteristics are in temporal patterns of calls.C. medius andM. murinus, the Cheirogaleid species, use tonal calls and encode individual characteristics in frequency patterns. Despite the fundamental similarity in the call-structure of the two Cheirogaleid species different adaptations can be found to meet different ecological needs.  相似文献   

5.
The age and geographical distribution of fossil cercopithecids in China   总被引:2,自引:0,他引:2  
Cercopithecids did not arrive in China until the latest Tertiary, relatively late in their evolutionary history. Cercopithecines are represented in the Chinese fossil record by two genera,Procynocephalus andMacaca, both of which made their appearance in the Late Pliocene or Early Pleistocene, but only one of which,Macaca, was widely distributed throughout the Quaternary and remains in the country today. The much less well known genusProcynocephalus disappeared from China in the late Early Pleistocene, but is of considerable interest because it appears to have been part of a radiation of large terrestrial cercopithecines that extended throughout portions of southern and eastern Asia. Colobines are poorly represented in the fossil record of China. Aside from a few scattered occurrences ofRhinopithecus in the Middle and Late Pleistocene records of southern China, the subfamily is represented by only one other intriguing specimen. This is the large and nearly complete mandible now classified as «Megamacaca lantianensis» from the Gongwangling locality of Lantian, Shaanxi Province. The specimen was retrieved from sediments of late Early Pleistocene age and was associated with elements of a typical southern,Ailuropoda — Stegodon fauna. The distribution of cercopithecids, especiallyMacaca, in China followed the southern and eastern retreat of subtropical habitats during the course of the Pleistocene.  相似文献   

6.
The prevalence of NIDDM in the «Punjabi» population from north India corroborates the «epidemiological transition» model. Hospital admittees gave a higher prevalence of NIDDM in urban areas (8.2–9.3 percent), as compared to rural areas (2.4 percent), and this difference probably is the outcome of the respective lifestyles. Moreover, urban residents are 3.7 times more likely to develop diabetes than are rural residents. Principal component analysis suggests a high correlation of NIDDM with age, BMI, systolic and diastolic blood pressure. The combined relative risk of diabetes with hypertension as a risk factor was 5.16 (p<.0001). Findings indicate that a combination of risk factors show significant association with diabetes.  相似文献   

7.
Abstract

«Pinus mugo» Turra and «Pinus uncinata» Miller in Piedmont. Critical notes and distribution. — The Authors have carried on a research on the distribution of Pinus mugo Turra (sensu Fl. Eur.) and Pinus uncinata Miller in all Piedmont Alpes and, having observed the extreme variability of the characters which are employed in the keys of determination to differentiate these two species, they suggest other and more constant characters. These are:

Table  相似文献   


8.
S. Ragusa 《BioControl》1974,19(1):61-66
The author has studied the influence of different temperatures (22°, 24°, 26°, 28°C) on oviposition and longevity ofOpius concolor siculus Mon., studying separately 13 couples at 22°, 15 at 24°, 100 at 26° and 11 at 28°C. The optimum temperature has been found to be 26°C. Differences have been observed betweenO. concolor Szepl. «African» andO. concolor siculus Mon. «Sicilian».  相似文献   

9.
Acacia guilandinae DC. is recognized asMimosa guilandinae (DC.) Barneby, endemic to French Guiana and adjoining Amapá, Brazil;M. pseudo-obovata is subordinated as a Brazilian var.pseudo-obovata (Taub.) Barneby to CaribbeanM. ceratonia L.; andM. laticifera is found synonymous withM. obovata Benth. Diagnostic morphological characters of each taxon are presented in key form.  相似文献   

10.
11.
The expression of nine functional candidates for QT abdominal fat weight and relative abdominal fat content was investigated by real-time polymerase chain reaction (PCR) in the liver, adipose tissue, colon, muscle, pituitary gland and brain of broilers. The high mobility group AT-hook 1 (HMG1A) gene was up-regulated in liver with a ratio of means of 2.90 (P?≤?0.01) in the «fatty» group (relative abdominal fat content 3.5?±?0.18%, abdominal fat weight 35.4?±?6.09 g) relative to the «lean» group (relative abdominal fat content 1.9?±?0.56%, abdominal fat weight 19.2?±?5.06 g). Expression of this gene was highly correlated with the relative abdominal fat content (0.70, P?≤?0.01) and abdominal fat weight (0.70, P?≤?0.01). The peroxisome proliferator-activated receptor gamma (PPARG) gene was also up-regulated in the liver with a ratio of means of 3.34 (P?≤?0.01) in the «fatty» group relative to the «lean» group. Correlation of its expression was significant with both the relative abdominal fat content (0.55, P?≤?0.05) and the abdominal fat weight (0.57, P?≤?0.01). These data suggest that the HMG1A and PPARG genes were candidate genes for abdominal fat deposition in chickens. Searching of rSNPs in regulatory regions of the HMG1A and PPARG genes could provide a tool for gene-assisted selection.  相似文献   

12.
13.
The paper treats the taxonomy of the genus Systenostrema Hazard & Oldacre, 1975, starting with an ultrastructural investigation of two new species, parasitic in larvae of the dragonflies Aeshna grandis and Libellula quadrimaculata, collected in Sweden. The two species are identical in pathology and presporal stages, but differ in the shape of spores and sporophorous vesicles, the fine structure of the spores, and numerical characters. The new species, which are named S. alba and S. candida, are compared to the octosporoblastic microsporidia parasitic in Odonata. An emended diagnosis of the genus Systenostrema is given, together with a taxonomic summary. The new combinations S. trichostegiae for Thelohania trichostegiae Baudoin, 1969 and Amblyospora capillata for T. capillata Larsson, 1983 are established.  相似文献   

14.
Previously, we have reported the role of MAPKs (mitogen-activated protein kinases) under cadmium stress. This work continue to explore the relationship between MAPKs, H2O2, auxin signaling, and OsHMA and OsZIP gene expression in rice (Oryza sativa L.) roots under combined cadmium (Cd) and zinc (Zn) stress. Compared with Cd, Cd+Zn reduced Cd levels but increased Zn accumulation in the roots. Three OsMAPK genes were negatively regulated, while two OsHMA and two OsZIP genes were positively regulated by MAPK pathways under Cd+Zn stress. Transgenic rice expressing DR5-GUS exhibited enhanced GUS activity in H2O2-, PD (MAPKK inhibitor PD98059)-, or (Cd+Zn)-treated roots, which also exhibited increased H2O2 concentrations, whereas GUS staining decreased in roots in response to Cd+Zn+PD, DMTU (N,N′-dimethylthiourea, a H2O2 scavenger), or Cd+Zn+DMTU treatment, with reduced H2O2 levels. GUS levels were consistent with H2O2 levels, suggesting that MAPK pathway-mediated auxin redistribution occurs via H2O2, and H2O2 functions downstream of MAPK but upstream of auxin signaling pathways. Furthermore, MAPK pathways serve specific functions in regulating the expression of some key genes of auxin signaling (OsYUCCA, OsPIN, OsARF, and OsIAA) under Cd+Zn stress. Overall, MAPK cascades function in the integration of metal transport, H2O2 generation, and auxin signaling in rice seedlings grown under Cd+Zn stress.  相似文献   

15.
Chromosomes and sex determination of 9 species of Haemaphysalis assigned to 4 subgenera are described. H. (tAlloceraea) kitaokai possesses an XX∶XO sex chromosome system with 18 autosomes plus XX in females; 18 plus X in males. H. (Kaiseriana) hystricis has 18 +XX and 18 + XY in females and males, respectively, in most specimens, but a supernumerary chromosome is present in some individuals. A supernumerary chromosome was also observed in 1 male H. (Aborphysalis) formosensis. These two species are the second and third species of ticks reported to have supernumerary chromosomes. H. formosensis, H. (Kaiseriana) bispinosa, H. (Haemaphysalis) campanulata, H. (H.) flava, H. (H.) megaspinosa, H. (H.) japonica, and H. (H.) pentalagi possess 20 autosomes plus 2 sex chromosomes in females and 20+1 sex chromosomes in males. Phylogenetic relationships within the genus Haemaphysalis are briefly discussed.  相似文献   

16.
The species composition of centric diatoms from Lake Frolikha (Transbaikal area) has been studied. The lake is located on the eastern shore of Lake Baikal and connected with it by a river. Twenty-three species of Centrophyceae from 7 genera (Aulacoseira, Cyclostephanos, Cyclotella, Discostella, Handmania, Pliocaenicus, and Stephanodiscus) have been found. The most represented genus is Aulacoseira (11 species). Fifteen species and 4 genera are new for the lake record. All revealed species are known in other lakes of the Baikal region; however Baikal endemics are absent in Lake Frolikha. The flora of centric diatoms in Lake Frolikha can be divided into two groups. The first group includes taxa common in Lake Baikal, and the second group includes taxa not typical for Lake Baikal. The level of differences between flora in Lake Baikal and Lake Frolikha is high (43%) despite the close location and connection to the river. An analysis of distribution of interesting species in Asia is presented.  相似文献   

17.
18.
Combinations of DNA-binding fluorescent dyes and counterstains that enhance selectivity and contrast in primary stain fluorescence were used to differentiate types of C-bands in the genus Warramaba. Chromomycin A3 (in conjunction with two A-T binding counterstains), which identifies chromosome segments enriched in G-C base pair clusters, stains only a minority of the C-bands in Warramaba species, but these include all those known to contain 18S + 26S rRNA cistrons and most of those containing 5S rRNA genes. DAPI/actinomycin D fluorescent staining is positive for a very few bands, including two (in the Standard phylad of W. virgo) that are at or adjacent to sites containing 5S rRNA cistrons. One of the latter regions is also positively stained by DAPI/distamycin A which, in addition, highlights some centromeric bands. The fluorescent staining patterns of the Standard and Boulder-Zanthus phylads of W. virgo are significantly different, confirming their independent origin by hybridization between different races of the ancestral species “P169” and “P196”.  相似文献   

19.
The laboratory strains of Chlamydomonas reinhardtii have been reported to contain no phosphatidylcholine (PC), which is considered to be replaced by another zwitterionic lipid, diacylglyceryl-N,N,N-trimethylhomoserine (DGTS). According to the recently published classification, the strains belonged to the subgroup Reinhardtinia. Screening for PC in 13 selected strains of Chlamydomonas in the NIES Algal Collection, which are different in habitats and belong to different phylogenetic subgroups in the genus, revealed the presence of PC in four strains: a strain in the subgroup Polytominia, and three strains in Reinhardtinia. PC was not detected in three other strains of Reinhardtinia analyzed. The presence/absence of PC was not related to the phylogenetic relationship based on 18S rRNA. DGTS was detected in all the strains analyzed. The rare isomer of linolenic acid, 18:3(5,9,12), which has been found in the DGTS of C. reinhardtii, was found in the PC of the two strains and in the DGTS of the five strains. The occurrence of this fatty acid seems limited to a branch of Reinhardtinia. Acquisition and loss of PC in various strains of Chlamydomonas are discussed from the viewpoint of evolution of PC biosynthetic pathway.  相似文献   

20.
Jack Maze 《Brittonia》1968,20(4):321-333
Introgression between two allopatric species,Quercus macrocarpa andQ. gambelii, has been observed in two separate locations: northeastern New Mexico and the Black Hills of western South Dakota and adjacent Wyoming. The probability that this introgression is the result of long-range pollination appears remote. Presumably these two species hybridized during a period of past sympatric association. Further indication of past sympatry in the Black Hills is the presence of a common species of obligate parasite, i.e., wasp(Cynips insulensis) onQ. gambelii in the Rocky Mountains and onQ. macrocarpa of the Black Hills. The hybrid oaks in New Mexico probably reflect a westward migration ofQ. macrocarpa during pluvial periods of the Pleistocene.Quercus gambelii most likely reached the Black Hills during the warmer postglacial hypsithermal era. The hybridization reported here may reflect secondary sympatry, i.e., sympatric occurrence after the species, or their ancestors, became geographically separated.  相似文献   

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