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1.
Renewed excavations at Die Kelders Cave 1 on the southern South African coast have uncovered large collections of Middle Stone Age (MSA) stone artefacts and coloring materials, but not bone or shell artefacts. High percentages of silcrete artefacts in one of the lower layers are confirmed, but there is no evidence for the Howieson's Poort stage of the MSA as previously mooted. The artefacts probably date to the middle-late MSA. The consistency and conservation which characterize the Die Kelders and other non-Howieson's Poort MSA artefact sequences contrast with the faster changes and innovative patterning seen in Later Stone Age sequences. It is not known whether this picture is a consequence of the traditional typological approach to MSA stone artefact analysis, or whether it reflects differences between Middle and Later Stone Age tool-makers in biological cognition capabilities or merely in social relations and world views.  相似文献   

2.
Since 1991, excavations at Blombos Cave have yielded a well-preserved sample of faunal and cultural material in Middle Stone Age (MSA) levels. The uppermost MSA phase, M1, is dated to c. 75 ka by optically stimulated luminescence (OSL) and thermoluminescence, and the middle M2 phase to a provisional c. 78 ka. Artefacts unusual in a MSA context from these phases include bifacial points, bone tools, engraved ochre and engraved bone. In this paper, we describe forty-one marine tick shell beads recovered from these MSA phases and tick shell beads from Later Stone Age (LSA) levels at Blombos Cave and the Die Kelders site. Thirty-nine shell beads come from the upper M1 phase and two from M2. Morphometric, taphonomic and microscopic analysis of modern assemblages of living and dead tick shell demonstrate that the presence of perforated Nassarius kraussianus shells in the Blombos MSA levels cannot be due to natural processes or accidental transport by humans. The types of perforation seen on the MSA shells are absent on modern accumulations of dead shells and not attributable to post-depositional damage. Their location, size, and microscopic features are similar to those obtained experimentally by piercing the shell wall, through the aperture, with a sharp bone point. Use-wear, recorded on the perforation edge, the outer lip, and the parietal wall of the aperture indicates the shells having being strung and worn. MSA shell beads differ significantly in size, perforation type, wear pattern and shade compared to LSA beads and this eliminates the possibility of mixing across respective levels. Thirty-one beads were found in four groups of five to twelve beads, each group being recovered in a single square or in two adjacent sub-squares during a single excavation day. Within a group, shells display a similar shade, use-wear pattern and perforation size suggesting their provenance from the same beadwork item, lost or disposed during a single event. The likely symbolic significance of these finds suggests levels of cognitively modern behaviour not previously associated with MSA people.  相似文献   

3.
A detailed taphonomic analysis is reported for a sample of the larger mammalian faunal assemblage (>4.5 kg live body weight) from Blombos Cave. The analysis provides an assessment of human involvement in the accumulation and modification of the faunal assemblage, and precedes equally detailed analyses and separate reports of Middle Stone Age (MSA) butchery, transport, and hunting behaviour. At Blombos, there are clear differences in the relative abundances of ungulate body size classes, with the lower MSA phases (upper/lower M2 and M3) showing a high representation of size 1 ungulates relative to the most recent MSA phase (M1). The bones from the earliest MSA phase (M3) have not undergone much post-depositional fragmentation, in contrast to fragments from more recent phases (M1 and upper M2). Much of this variability can be attributed to more burning activity and trampling during M1 and upper M2, which could indicate more intensive occupation. Bone surfaces are variably preserved, with high levels of exfoliation in the most recent two phases. Surface modification analyses revealed high proportions of human modification throughout the sequence, indicating that MSA humans were responsible for accumulating most of the larger mammals. After discard, the bones were modified by scavenging carnivores, leading to a moderate amount of density-mediated destruction and tooth-marking. Carnivores independently accumulated some of the smaller ungulates, mainly in the form of partially-digested remains. Raptorial birds are not implicated as major faunal accumulators. The results from Blombos are directly comparable with analogous datasets from two other sites in the Western Cape (Pinnacle Point Cave 13B and Die Kelders Cave 1). Such comparisons demonstrate that MSA faunal assemblages from nearby coastal sites have complex and different taphonomic histories both within and between sites. Because the human occupants were a major part of these processes, MSA subsistence behaviour and site use was also quite variable over time and space.  相似文献   

4.
A detailed taphonomic analysis is provided for the mammalian and tortoise faunal assemblages from Pinnacle Point Cave 13B (PP13B). It is the first of several reports on the fauna from this site, and must necessarily precede analyses focused on higher level interpretations of Middle Stone Age (MSA) butchery, transport, and hunting behavior. The taphonomic work shows that the faunal assemblage is well preserved and there are discernable differences in the taphonomic pathways to which the fauna was subjected at PP13B between the Middle and Late Pleistocene, between the front and back of the cave, and between body size classes. The largest mammals (size classes 2-5, body weight >24?kg) were mainly accumulated by MSA hominins. Size class 1 ungulates also exhibit a degree of hominin modification consistent with some hominin accumulation of fresh carcasses, but this is more variable through time and includes an observable degree of independent carnivore contribution. Basic taxonomic comparisons reveal a low representation of small mammals, tortoises, and marine mammals at PP13B relative to larger (>4.5?kg) terrestrial mammals. This is a different pattern from other MSA sites along the southwestern coast of South Africa, where small mammals and tortoises are abundant. A microscopic study of the bone surfaces confirms that MSA hominins exploited these small faunal components opportunistically, while focusing most heavily on large terrestrial ungulates. All faunal components show evidence of carnivore scavenging of hominin food debris and a high degree of density mediated destruction. Raptors are at no point implicated as major accumulators of any fauna. The study demonstrates that the full spectrum of MSA faunal exploitation can only be understood when the large mammal, small mammal, and tortoise components of fossil assemblages have all been subjected to comprehensive taphonomic analyses.  相似文献   

5.
Excavations conducted by H.J. Deacon in the 1970s at Boomplaas Cave (BPA) uncovered a stratified sequence of Middle Stone Age (MSA) and Later Stone Age (LSA) deposits spanning the last >65,000 years. This study provides the first comprehensive and integrated taphonomic and paleoecological analysis of the BPA large mammals, with a focus on its implications for understanding human adaptations and environmental changes in southern Africa's Cape Floristic Region (CFR), an area that features prominently in understanding modern human origins. Taphonomic data indicate a complex history of human, carnivore, and raptor accumulation of the large mammal assemblage. The anthropogenic signal is largely absent from the bottom of the sequence (>65,000 years ago), intermediate in MSA and LSA assemblages from ∼50,000 to 20,000 years ago, and strong in LSA deposits post-dating the Last Glacial Maximum (LGM). When viewed in the broader CFR context, the inferred occupation history of BPA is consistent with the hypothesis that both MSA and LSA human populations were concentrated on the submerged coastline from ∼60,000 to ∼20,000 years ago. Intensive occupation following the LGM parallels an apparent increase in regional population densities, which may have been driven in part by rising sea levels. The BPA ungulate assemblage is characterized by the rise and decline of a taxonomically diverse grazing community, which peaks during the LGM. These changes are not correlated with taphonomic shifts, meaning that they are likely driven by environmental factors, namely the expansion and contraction of grassland habitats. Changes in ungulate diversity indicate that effective precipitation was highest during the LGM, corresponding with an intensified winter rainfall system. This is consistent with recent arguments that the LGM in this region may not have been extremely harsh and arid.  相似文献   

6.
Patterns of faunal exploitation play a central role in debates concerning the behavioral modernity of Middle Stone Age (MSA) peoples. MSA foragers have been portrayed as less effective hunters than their Later Stone Age (LSA) successors on the basis of relative species abundances from ungulate assemblages in southern Africa. Specifically, MSA hunters are said to focus on docile eland while avoiding more aggressive prey, particularly buffalo and wild pigs. To evaluate these arguments and compare subsistence behavior, I present a quantitative examination of 51 MSA and 98 LSA ungulate assemblages from southern Africa to show that: (1) with respect to ungulate exploitation, MSA diet breadth may have exceeded LSA diet breadth, (2) ungulate assemblage evenness is equivalent in the MSA and LSA, (3) eland, buffalo, and wild pig are equally abundant in the MSA and LSA, and (4) large ungulate prey are more common in the MSA than in the LSA. With few exceptions, the broad patterns, which sample a range of geographic and environmental contexts, are supported by an environmentally controlled comparison of Middle and Later Stone Age faunas that accumulated under interglacial conditions along the southern African coastline. When interpreted within a foraging theory framework, these differences suggest that MSA hunters enjoyed increased meat yields due to elevated encounter rates with large prey. These results need not imply cognitive differences, but are consistent with an increase in human populations from the Middle to Later Stone Age, which resulted in diminished abundances of large ungulates.  相似文献   

7.
The uppermost Middle Stone Age (MSA) layers at Blombos Cave contain high densities of Still Bay bifacial points. Information from other regional sites places the Still Bay prior to the Howiesons Poort industry, which has been dated at 65-70 ka. The Blombos Cave MSA strata have yielded nine human teeth or dental fragments. Four that were recovered during the 1997-1998 excavations have been published elsewhere. The remaining five were discovered during the 1999-2000 field seasons; these are described here. Three of the new specimens are deciduous teeth, and two are permanent premolar and molar crown fragments. The entire dental sample probably represents at least five and as many as seven individuals. The deciduous teeth from the upper MSA levels are likely to have been exfoliated in the cave. One deciduous tooth and the permanent tooth fragments from the lower MSA levels probably represent three individuals who died in or near the cave. The Blombos Cave premolars preserve horizontal circum-cervical striae suggestive of palliative tooth pick use. Approximately half of the permanent and deciduous crown diameters exceed those of recent Africans; for the remainder, the fossil values fall among modern African sample means. The Blombos Cave tooth crowns tend to be smaller than the majority of penecontemporaneous Neandertal teeth. The morphology of the Blombos Cave di is comparable to MSA homologues from the nearby, and presumably somewhat younger site of Die Kelders Cave 1.  相似文献   

8.
Middle Stone Age (MSA) and Middle Paleolithic (MP) faunal assemblages have gained widespread attention due to their relevance to the debate over the modernity of hominid behavior during the MSA/MP. A recent critique of the scavenging argument for MSA/MP behavior drew on a summary presentation of the skeletal abundance and surface modification data from Die Kelders Cave 1 Layer 10 (Marean, 1998). This paper provides a more complete presentation of those data, adds the smaller Layer 11 sample, and provides a detailed analysis of the taphonomic history of both samples.Bone fragment density is higher in Layer 10 than in Layer 11. Bone densities vary horizontally as well, with Layer 10 showing greater deposition in the exposed areas of the cave. An analysis of long bone breakage patterns indicates that non-nutritive breakage on the Layers 10 and 11 samples was present but not intense. Size 1 mammals were predominantly accumulated by owls and/or other large raptors, not hominids, in Layer 10. Hominids were the predominant accumulator of Sizes 2-4 mammals in Layers 10 and 11 as indicated by the frequency of hammer-stone percussion marks and carnivore toothmarks. After discard by hominids, a significant portion of these remains were discovered and scavenged by carnivores. Overall, the larger mammal fauna of Layer 10 is dominated by Sizes 3 and 4 bovids, mostly young and adult eland, and thus hominids were focusing on the high-ranked prey items. Shaft portions of long bones, the portions with the most flesh, have the highest frequencies of cutmarks. A comparison of the Layers 10 and 11 cutmark frequencies to Selvaggio's (1998) scavenging model shows that the frequencies are significantly outside the range of variation documented in Selavaggio's scavenging sample.  相似文献   

9.
The deposits of Die Kelders I were previously described and studied by Tankard & Schweitzer (1974, 1976) from the standpoint of classical granulometric analysis of sand from a coastal cave in order to infer the geological history of the cave and its environs. This paper supplements these earlier works by taking a more holistic approach toward site formation processes by including investigation of the biogenic and anthropogenic influences on the cave deposits and history. The study employs the technique of soil micromorphology, which is the study of resin-impregnated, undisturbed blocks of sediment and petrographic thin sections, in which sediments from all areas of the cave were examined. The study showed that diagenesis of the deposits in the eastern areas of the excavation resulted in decalcification, which in turn brought about slumping and compaction. Equivalent stratigraphic layers exposed in the western and central areas were only mildly decalcified and consequently, these sediments contain limestone rock fall and relatively abundant marine and terrestrial mollusks, the latter not dissimilar to the Late Stone Age (LSA) midden which covers these deposits. Thus, in spite of lowered and more distant shorelines, marine resources were exploited during Middle Stone Age (MSA) times. Observations from these calcareous units also clearly demonstrates that previously recognized "occupational horizons" (e.g. Layers 6, 8 and 10) can be resolved micromorphologically into several ephemeral events, such as burning/fire, redistribution of ashes by wind and water, and non-deposition; the latter is shown by phosphatic alteration of sediments exposed on former surfaces and accumulation of guano, or the presence of millimeter-thick truncation surfaces below which aeolian dust infiltrated. Both field and microscopic observations illustrate that the deposits in caves are highly variable from wall to center, and that excavations should not be localized in just one microenvironment of the cave site.  相似文献   

10.
Die Kelders Cave 1, first excavated under the direction of Franz Schweitzer in 1969-1973, was re-excavated between 1992 and 1995 by a combined team from the South African Museum, SUNY at Stony Brook, and Stanford University. These renewed excavations enlarged the artefactual and faunal samples from the inadequately sampled and less intensively excavated lower Middle Stone Age (MSA) layers, increased our understanding of the complex site formation processes within the cave, enlarged the hominid sample from the MSA deposits, and generated ESR, TL, and OSL dates for the MSA layers. Importantly, these new excavations dramatically improved our comprehension of the vertical and lateral characteristics of the MSA stratigraphy. Surface plotting of the MSA layers has led to the identification of at least two major zones of subsidence that significantly warped the layers, draping some along the eroding surface contours of major blocks of fallen limestone roof rock. A third zone of subsidence is probably present in the older excavations. Dramatic roof falls of very large limestone blocks occurred at least twice-once in the middle of Layer 4/5 where the roof blocks were only slightly weathered after collapse, and at the top of Layer 6 where the blocks weathered heavily after collapse, producing a zone of decomposed rock around the blocks. Many of the sandy strata are cut by small and localized faults and slippages. All of the strata documented by Schweitzer's excavations are present throughout the exposed area to the west of his excavated area, where many of them thicken and become more complex. Layer 6, the thickest MSA layer, becomes less diagenetically altered and compressed to the west.  相似文献   

11.
Luminescence dating of sediments has not been used extensively for dating Middle Stone Age deposits in South Africa, despite its potential for contributing to a poorly dated record. Such deposits at Die Kelders cave, on the southern South African coast, consist of narrow bands of occupation debris separated by thicker layers of aeolian sands containing much less evidence of occupation. Homogeneous, aeolian sediments are usually considered ideal for luminescence dating. Here we report luminescence analyses of five samples from these sands that demonstrate sufficient bleaching prior to burial to validate dating and that yield ages of about 60-70 ka, in agreement with other evidence from sedimentology, archaeology and electron spin resonance. Lack of significant differences in the ages suggests the deposits accumulated fairly rapidly during the early part of the Last Glaciation.  相似文献   

12.
Recent genetic studies based on the distribution of mtDNA of haplogroup U6 have led to subtly different theories regarding the arrival of modern human populations in North Africa. One proposes that groups of the proto-U6 lineage spread from the Near East to North Africa around 40–45 ka (thousands of years ago), followed by some degree of regional continuity. Another envisages a westward human migration from the Near East, followed by further demographic expansion at ∼22 ka centred on the Maghreb and associated with a microlithic bladelet culture known as the Iberomaurusian. In evaluating these theories, we report on the results of new work on the Middle (MSA) and Later Stone (LSA) Age deposits at Taforalt Cave in Morocco. We present 54 AMS radiocarbon dates on bone and charcoals from a sequence of late MSA and LSA occupation levels of the cave. Using Bayesian modelling we show that an MSA non-Levallois flake industry was present until ∼24.5 ka Cal BP (calibrated years before present), followed by a gap in occupation and the subsequent appearance of an LSA Iberomaurusian industry from at least 21,160 Cal BP. The new dating offers fresh light on theories of continuity versus replacement of populations as presented by the genetic evidence. We examine the implications of these data for interpreting the first appearance of the LSA in the Maghreb and providing comparisons with other dated early blade and bladelet industries in North Africa.  相似文献   

13.
Die Kelders Cave 1 (DK1) preserves a thick series of Middle Stone Age (MSA) horizons that date to a fairly short temporal interval sometime between about 60 and 80 ka ago. Twenty-seven human fossils, comprising 24 isolated teeth, a mandibular fragment, and two manual middle phalanges derive from seven of the 12 layers. The vast majority are children, and all may have come from sub-adult individuals. The entire assemblage may represent a minimum of ten individuals. As might be expected for teeth of such antiquity, most of the DK1 crowns tend to be large in comparison to recent African homologues. They tend to be smaller than, albeit more similar in size to, the teeth of penecontemporaneous archaic populations from Eurasia. The majority of morphological variants displayed by the DK1 crowns characterize the teeth of recent sub-Saharan Africans, and the DK1 crowns resemble those of recent Africans in a number of traits that have been used to define a sub-Saharan African regional complex. The morphological similarities between the DK1 MSA and recent African teeth, however, do not necessarily signify a close evolutionary relationship between them, because these crowns variants appear to be plesiomorphic.  相似文献   

14.
Optically stimulated luminescence (OSL) measurements are reported for both single aliquots (of two different sizes) and single grains of quartz from deposits within Blombos Cave. Ages have been obtained for six sediments from the Middle Stone Age (MSA) occupation levels and for two sterile sands, one underlying the archaeological sediment and one overlying the Later Stone Age occupation levels. The ages for the archaeological sediments were obtained from single-grain measurements that enabled unrepresentative grains to be rejected. The MSA occupation levels have ages that, within error limits, are in stratigraphic order and fall between the OSL age for the oldest dune sand (143.2+/-5.5 ka) and a previously published OSL age for the sterile sand ( approximately 70 ka) that separates the Middle and Later Stone Age deposits. The earliest MSA archaeological phase, M3, from where fragments of ochre were found as well as human teeth, is dated to 98.9+/-4.5 ka, coinciding with the sea-level high of oxygen isotope substage 5c. The cave then appears to be unoccupied until oxygen isotope substage 5a on the basis of four OSL ages for archaeological phase M2, ranging from 84.6+/-5.8 to 76.8+/-3.1 ka; these levels contained large hearths and bone tools. An age of 72.7+/-3.1 ka was obtained for the final MSA archaeological phase, M1, from which deliberately engraved ochre and shell beads were recovered along with bifacial stone points. We conclude that the periods of occupation were determined by changes in sea level, with abundant sources of seafood available in times of high sea level and with the cave being closed by the accumulation of large dunes during periods of low sea level, such as during oxygen isotope stages 4 and 6.  相似文献   

15.
The Middle to Later Stone Age (MSA/LSA) transition is a prominent feature of the African archeological record that began in some places ~30,000–60,000 years ago, historically associated with the origin and/or dispersal of “modern” humans. Unlike the analogous Middle to Upper Paleolithic transition in Eurasia and associated Neanderthal extinction, the African MSA/LSA record remains poorly documented, with its potential role in explaining changes in the behavioral diversity and geographic range of Homo sapiens largely unexplored. I review archeological and biogeographic data from East Africa, show regionally diverse pathways to the MSA/LSA transition, and emphasize the need for analytical approaches that document potential ancestor‐descendent relationships visible in the archeological record, needed to assess independent invention, population interaction, dispersal, and other potential mechanisms for behavioral change. Diversity within East Africa underscores the need for regional, rather than continental‐scale narratives of the later evolutionary history of H. sapiens.  相似文献   

16.
We translocated 120 Agassiz's desert tortoises to 5 sites in Nevada and Utah to evaluate the effects of translocation on tortoise survivorship, reproduction, and habitat use. Translocation sites included several elevations, and extended to sites with vegetation assemblages not typically associated with desert tortoises in order to explore the possibility of moving animals to upper elevation areas. We measured survivorship, reproduction, and movements of translocated and resident animals at each site. Survivorship was not significantly different between translocated and resident animals within and among sites, and survivorship was greater overall during non-drought years. The number of eggs produced by tortoises was similar for translocated and resident females, but differed among sites. Animals translocated to atypical habitat generally moved until they reached vegetation communities more typical of desert tortoise habitat. Even within typical tortoise habitat, tortoises tended to move greater distances in the first year after translocation than did residents, but their movements in the second or third year after translocation were indistinguishable from those of resident tortoises. Our data show that tortoises translocated into typical Mojave desert scrub habitats perform well; however, the large first-year movements of translocated tortoises have important management implications. Projects that employ translocations must consider how much area will be needed to contain translocated tortoises and whether roads need fencing to prevent the loss of animals. © 2012 The Wildlife Society.  相似文献   

17.
This paper examines variability and the emergence of the Howiesons Poort within the Middle Stone Age lithic technologies of Klasies River Mouth. Here I present a pattern recognition study using multivariate statistical techniques examining the data presented by [Singer, R., Wymer, J.J., 1982. The Middle Stone Age at Klasies River Mouth in South Africa. Chicago University Press, Chicago]. Using this model, the Middle Stone Age (MSA) lithics from Klasies River Mouth load on three main factors: (1) a Levallois flake manufacture factor, (2) a blade manufacture factor, and (3) a worked point factor. The MSA I assemblage from Cave 1 and the MSA II assemblage from Shelter 1a correlate strongly with the worked point factor, the MSA II assemblage from Cave 1 correlates strongly with the Levallois factor, and the Howiesons Poort assemblage from Shelter 1a correlates strongly with the blade factor. The Howiesons Poort from Shelter 1a is differs more from all other industries than the remaining industries do from each other. In addition, the Howiesons Poort from Cave 2 groups closely with the MSA III assemblage from Shelter 1a due to similarities in raw material frequencies.  相似文献   

18.
Documentation of variation in phalangeal formulae in land tortoises combined with ontogenetic information from turtles in general were used, in a phylogenetic context, to infer the potential effect of size and developmental constraints upon patterns of morphological variation. A sample of 201 specimens and published illustrations of 37 tortoise species were examined, representing all but one living genera and most species of the Testudinidae. Specimens were either articulated dry skeletons or preserved animals that were x-rayed. The patterns of digital and phalangeal loss in tortoises were predicted from developmental studies of the manus and pes in other turtles. If a digit is lost, it is the first digit, which is the last one to develop. If a digit has a single phalanx, it is usually the fifth digit. The primitive phalangeal formula for land tortoises is probably 2-2-2-2-1, the most common pattern found in living testudinid species. The presence of a second phalanx in the fifth digit evolved independently many times and usually in large tortoises. Such additions were interpreted as instances of peramorphosis. Many small tortoises have a full complement of digits (five) and phalanges (two in each digit); nevertheless, phalangeal and digital loss is associated with small size. Small and medium size tortoises exhibit greater variation in phalangeal number than do large tortoises. We hypothesize that epigenetic processes, and not simply adaptation, played a major role in the evolution of the variation in phalangeal formulae in tortoises.  相似文献   

19.
Hominids from the site of Border Cave purportedly provide direct evidence for the early emergence of anatomically modern humans (AMH) in Southern Africa. ESR dating of Border Cave faunal enamel has confirmed the antiquity of the sediments, although questions persist regarding the provenience of the hominid specimens. Here we establish that, at Border Cave as elsewhere, bone mineral crystallinity, measured as the infrared (IR) splitting factor (SF), distinguishes between contemporary and recent bones on the one hand, from Middle Stone Age (MSA) bones on the other. Two hominid postcranial bones recovered in 1987 from a slumped profile, having essentially no provenience, are shown to have crystallinity indices consistent with the MSA fauna, while two of the purportedly ancient AMH specimens (BC3 and BC5) have values consistent with recent fauna. We conclude that BC3 and BC5 may be considerably younger than the sediments from which they were recovered.  相似文献   

20.
Wildlife translocations, the deliberate movement of animals from one part of their distribution to another, are increasingly used as a conservation method for the reestablishment of rare and endangered species. The objective of this study was to examine the movement patterns and macro- and microhabitat use of translocated and resident spur-thighed tortoises. This translocation was considered a soft-release as the tortoises were forced to be relatively inactive due to their being released at the beginning of the aestivation season. Our results suggest that forced aestivation soft-releases may succeed in reducing dispersal by forcing spur-thighed tortoises to spend time at the release site as the majority of translocated tortoises had similar activity range sizes and movement path tortuosity as resident tortoises. Spur-thighed tortoise conservation will require protecting habitat at multiple scales, with the remaining native forests in the country of Jordan being important to the spur-thighed tortoise during the activity and aestivation/hibernation seasons, as this macrohabitat was used significantly more than the human-modified habitats. Microhabitat structures such as leaf litter and availability of large stones may also be especially important in human-modified landscapes, as these microhabitats may help reduce the effects of habitat degradation.  相似文献   

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