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1.
Karine Louise dos Santos Nivaldo Peroni Raymond Paul Guries Rubens Onofre Nodari 《Economic botany》2009,63(2):204-214
Traditional Knowledge and Management of
Feijoa (Acca sellowiana)
in Southern Brazil. This paper investigates traditional knowledge of the use and management of Acca sellowiana in southern Brazil. Fifty-six informants from three rural communities were assigned to one of four subgroups (“maintainers,”
“managers,” “cultivators,” or “users”) based on their responses regarding management and use of A. sellowiana. Traditional knowledge related to use of this species is widespread among rural residents, but traditional knowledge related
to management is fragmented depending on whether one uses, manages, or cultivates the species. Knowledge held in rural communities
suggests that A. sellowiana could play an expanded role in local economies as well as biodiversity conservation. We suggest that participatory research
could stimulate greater local use as well as on-farm conservation of A. sellowiana. 相似文献
2.
Abdel Gaffar Elhag Said Toshio Murashige 《In vitro cellular & developmental biology. Plant》1979,15(8):593-602
Summary Initial trials with tomato-root cultures disclosed the desirability of employing a gently agitated liquid medium containing
iron in the chelated form. For the normal cultivars “Ace” and “Tropic”, subcultures were best achieved by utilizing sectors
that possessed one or more newly emerged laterals. Continuous cultures of a nonlateral-forming tomato mutant, “Diageotropica”,
and of citron were accomplished by subculturing tips of the elongating primary roots. The tomato roots were cultured in White's
medium with the Fe2(SO4)3 replaced by 0.03 mM NaFeEDTA. Sustained growth of citron-root tips necessitated the use of a medium containing Murashige
and Skoog salts, 7.5% sucrose, 100 mg per I each of citric acid and thiamine HCl, and 5000 mg per li-inositol. The success with citron-root cultures was extendable to all cultivars ofC. medica L., but not to otherCitrus species relatives. Both citron and “Diageotropica” root cultures manifested undiminished elongation through repeated subcultures;
but neither produced laterals in response to any cultural treatments.
Research was supported in part by National Science Foundation Grant OIP75-10390 and Elvenia J. Slosson Fellowship in Ornamental
Horticulture. 相似文献
3.
Den sharing by conspecific spiny lobsters (aggregation) is modulated by chemical attraction but may confer several, not necessarily
mutually exclusive, antipredator byproduct benefits: a “guide effect”, which only benefits the individual attracted to a sheltered
conspecific; a “dilution effect”, which reduces per-capita risk of predation simply through aggregation; or active “group
defense”. Each potential benefit has a different set of predictors (relationships between aggregation and conspecific or predator
densities), but conflicting results could suggest the simultaneous operation of more than one benefit. These predictions were
tested for coexisting Panulirus guttatus (a reef-obligate) and Panulirus argus (a temporary reef-dweller) using data collected during 11 surveys on fixed sites over a coral reef in Mexico. P. guttatus greatly outnumbered P. argus, but P. argus showed a greater tendency to aggregate. All three benefits of den sharing operated for the more social P. argus, with “group defense” being of the most benefit for larger individuals, and the “guide” and “dilution” effects for smaller
individuals recently immigrating into the reef habitat and sharing dens with larger conspecifics. P. guttatus did not display “group defense” and its aggregations appeared to be modulated by the interplay between attraction and aggressive
behaviors. This species relied more on solitary crypticity, especially at larger sizes, but appeared to benefit from a “guide
effect” at high conspecific densities. In experimental tanks, each species tended to aggregate when tested separately, but
when tested jointly, aggregation among P. guttatus was significantly reduced. The experimental results reflect the differential patterns of aggregation between the fore-reef,
where P. guttatus dominated, and the back-reef, where coexistence of both species was greater. 相似文献
4.
Forestry is obliged to record as well as maintain and/or enhance biological diversity in forests due to national and international
agreements. Accordingly, it is necessary to work out methodological approaches for the assessment of biodiversity in forests.
In the study presented here, we focus on the total plant species pool (563 vascular plant and bryophyte species) of pine (Pinus sylvestris L.) forests in NE Germany to identify indicators for plant species richness. We distinguished several groups like “herb”,
“grass-like”, “woody”, “endangered”, and “exotic species”, for which we detected indicators for low (class #1), intermediate
(class #2), and high (class #3) species numbers. From a total of 84 species, which were identified by a three-step procedure,
most indicators were found for class #3. Only few indicators have been revealed for intermediate species numbers, i.e. class
#2. With help of Ellenberg’s ecological indicator values and information on the main occurrence in Central European vegetation
types and plant communities, respectively, we characterized the indicator species ecologically. The ecological site preferences
of the indicator species in general reflect the fact that species richness is highest in base-rich, light, and anthropogenically
disturbed pine forests. On the contrary, species-poor forests were revealed by indicators, which mainly occur on acidic sites.
It is concluded that a considerable set of indicators for species richness can help facilitate biodiversity assessments in
forestry and ecosystem restoration practice.
Electronic Supplementary Material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
5.
Leanne T. Nash Simon K. Bearder Todd R. Olson 《International journal of primatology》1989,10(1):57-80
At the time of the symposium, “Variability Within the Galagos,” at the 1986 IPS Congress, most participants were still using
Hill’s (1953) classification and nomenclature of galago species. All participants expressed some degree of dissatisfaction
with Hill’s species groups. Many described how it was proving increasingly problematic and inadequate as a means to organize
newly collected laboratory, museum, and field data. By the end of the symposium, a consensus about species diversity had emerged
which synthesized the current state of knowledge about galagos. The consensus of the participants was that the 11 species,
identified by Olson (1979, 1986), most closely approximates the available data about galago species diversity. The 11 species
are described. 相似文献
6.
7.
Disanthus cercidifolius Maxim. var. longipes H.T. Chang usually has two inflorescences growing in opposite directions in the axillae, but occasionally three inflorescences
grow paratactically. The typical flowering process could be divided into 4 periods: “Pre-dehiscence”, “Initial dehiscence”, “Full dehiscence” and “Withering”. Both the natural population and the planted population had a flowering peak of 15–35 days after the first flower bloomed.
There were significant differences between the time courses of flowering of the two populations. Out-crossing is the main
breeding system in this species. And autogamy decreases the risk of reproductive failure of this species. The main insect
pollinators of D. cercidifolius var. longipes are Episyrphus balteatus de Geer, Scaptodrosophila coracina Kikkawa and Peng, Polistes olivaceus de Geer, Apis cerana Fabricius, Nezara viridula L. and Coccinella septempunctata L., and so on. Among the insects, S. coracina and E. balteatus are the most important and efficient pollinators, but others are inefficient pollinators. Though wind pollination is not
efficient, it guarantees reproduction when insect pollinators are not available. “Mass flowering” is an adaptive behavior and reproductive strategy of this species, and “few fruiting” could be caused by the lack of pollinators. 相似文献
8.
Masayoshi Maehata 《Ichthyological Research》2001,48(3):283-287
The mating behavior of the rock catfish Silurus lithophilus (Siluriformes: Siluridae), a species endemic to the Lake Biwa system, was observed from May to July in 1989–1994 along the
rocky shore of the lake's outlet, the Seta River. The mating behavior of S. lithophilus involved a certain behavioral sequence: “chasing,”“clinging,” and “enfolding” while “squeezing” by the male; and “circling”
by the spawned pair. The mating behavior of this species was basically similar to that of S. biwaensis, but greatly different from that of S. asotus, which spawns in running water (in ditches). The mating behavior of S. lithophilus (and S. biwaensis) might have developed as an adaptation to lentic environments such as the shores of the large river or the lake.
Received: October 25, 2000 / Revised: February 25, 2001 / Accepted: March 8, 2001 相似文献
9.
Giuseppe C. Zuccarello Alan T. Critchley Jennifer Smith Volker Sieber Genevieve Bleicher Lhonneur John A. West 《Journal of applied phycology》2006,18(3-5):643-651
The systematics and taxonomy of Kappaphycus and Eucheuma (Solieriaceae) is confused and difficult due to morphological plasticity, lack of adequate characters to identify species and commercial names of convenience. These taxa are geographically widely dispersed through cultivation. Commercial, wild and herbarium sources were analysed; molecular markers provided insights into taxonomy and genetic variation, and where sources of genetic variation may be located. The mitochondrial cox2-3 and plastidal RuBisCo spacers were sequenced. There is a clear genetic distinction between K. alvarezii (“cottonii”) and K. striatum (“sacol”) samples. Kappaphycus alvarezii from Hawaii and some samples from Africa are also genetically distinct. Our data also show that all currently cultivated K. alvarezii from all over the world have a similar mitochondrial haplotype. Within Eucheuma denticulatum (“spinosum”) most African samples are again genetically distinct. Our data also suggest that currently cultivated E. denticulatum may have been “domesticated” several times, whereas this is not evident for the cultivated K. alvarezii. The present markers used do not distinguish all the morpho-types known in cultivation (e.g. var. tambalang, “giant” type) but do suggest that these markers may be useful to assess introductions and species identification in samples. 相似文献
10.
Christian Mitgutsch 《Theorie in den Biowissenschaften》2003,122(2-3):204-229
Summary After the rejection of the idealistic “vertebral theory of the skull,” the basic idea of the theory had been taken up again
by the German morphologist Carl Gegenbaur. He proposed a metameric ordering system of the vertebrate head based on a comparative
investigation of selachians. This “segmentation theory of the vertebrate head” had a stimulating effect on comparative anatomy.
Traces of the basic ideas are still inherent in the biological sciences. Despite the fact that Carl Gegenbaur proposed a rather
phylogenetic approach, his systematic investigations remained on a typological level. It is argued herein, that the reason
for that was his inability to perform his comparisons independent of a rather intuitive a priori hypothesis about phylogenetic relationships, thus leaving no possibilities for testing homologies. This is exemplified by
Carl Gegenbaur’s choice of species for comparative work as well as his use of these species in comparative work. Choosing
species for comparisons is discussed. 相似文献
11.
Habitat-forming species increase spatial complexity and alter local environmental conditions, often facilitating a diversified assemblage of plants and animals. Removal of dominant species, therefore, can potentially lead to pronounced changes in diversity and community structure through a series of negative and positive interactions involving several components of the community. Here we test community responses to the deletion of the dominant, canopy-forming alga Hormosira banksii from the mid-intertidal zone of wave-protected rocky shores in southern New Zealand. This species was removed in winter (July) from three 3×3-m areas at each of two platforms (Kaikoura and Moeraki) on the east coast of the South Island. Initially, 59 taxa occurred in stands, but there were only four algal species with greater than 5% cover and three mobile invertebrate species with more than five individuals per 0.25 m2. By 6 months after Hormosira removal, most fucoid and coralline algae had burned off, and there were blooms of ephemeral algae in the removal plots, but almost no change within controls. After 2 years, diversity declined by 44% relative to controls at Kaikoura and 36% at Moeraki, and the amount of bare space had increased by tenfold at Kaikoura and twofold at Moeraki. Few sessile or mobile invertebrates were present. Recruitment of Hormosira occurred after 14 months in the removal plots. At this time, a “press” disturbance was initiated into one half of each removal plot to test the effects of continued removal of Hormosira on diversity. Similar “end-points” of the control and “press” removal plots were not reached after 2 years, and even after Hormosira recruitment into the original “pulse” experiment there was little recovery of the community. In this mid-intertidal system with considerable thermal stress, and perhaps in others with few perennial species, diversity and community structure can critically depend on positive associations with a single dominant species.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
12.
Inconsistent use of terminology plagues the study and management of biological invasions. The term “invasive” has been used
to describe inter alia (1) any introduced non-indigenous species; (2) introduced species that spread rapidly in a new region; and (3) introduced
species that have harmful environmental impacts, particularly on native species. The second definition in various forms is
more commonly used by ecologists, while the third definition is pervasive in policy papers and legislation. We tested the
relationship between the invasiveness of an introduced species and its impact on native biodiversity. We quantified a species’
invasiveness by both its rate of establishment and its rate of spread, while its impact was assigned a categorical ranking
based on the documented effects of the invader on native species populations. We found no correlations between these variables
for introduced plants, mammals, fishes, invertebrates, amphibians and reptiles, suggesting that the mechanisms of invasion
and impact are not strongly linked. Our results support the view that the term “invasive” should not be used to connote negative
environmental impact. 相似文献
13.
D. E. Tyler 《Human Evolution》2001,16(2):81-101
There are now twelve significant hominid cranial fossils from the Lower and Middle Pleistocene of Java, all but two being
from the Sangiran site. Most of this material is well-known in the literature, but three skulls, possibly representing “Meganthropus” are here described in detail for the first time. Most scholars have assigned them all toHomo erectus, while others have suggested that they represent as many as four different hominoid taxa. The author argues that they represent
two possible species of hominids. “Meganthropus” I, II, and III are more massive than any of the knownH. erectus specimens. They are also relatively higher vaulted, apparently smaller brained, and have unusually thick lower occipital
planes. “Meganthropus” may represent a species that separated fromH. erectus upon its arrival to Java. 相似文献
14.
Joy B. Zedler John C. Callaway Julie S. Desmond Gabrielle Vivian-Smith Gregory D. Williams Gary Sullivan Alice E. Brewster Brian K. Bradshaw 《Ecosystems》1999,2(1):19-35
Although tidal wetland vegetation patterns are typically related to elevation, we hypothesized that the vertical range of
a species may shift where the topography is more heterogeneous. We examined plant species occurrences in relation to elevation,
proximity to the bay, and proximity to tidal creeks at a near-pristine wetland in San Quintín Bay, Baja California, Mexico.
At the whole-wetland scale, most species occurred primarily within a 30-cm elevation band (the marsh plain). However, Spartina foliosa occurred only at the bayward margin, even though “suitable” elevations were present further inland. A similar pattern was
found in San Diego Bay. At the microtopographic scale, three species on the marsh plain were strongly influenced by elevation,
whereas four species responded to both elevation and proximity to tidal creeks. The latter species tended to “avoid” the lower
10 cm of the marsh plain except near a tidal creek. Species richness was thus greater (by 0.6 species at the lowest 10-cm
class) at the tidal creek margin. Better drainage near creeks is the hypothesized cause. Our results help explain why species
that are transplanted to constructed wetlands do not always grow at the full range of elevations they occupy in natural wetlands.
We recommend that species be introduced to their modal elevation (determined from nearby reference marshes) and that salt-marsh
construction designs include topographic heterogeneity (complex tidal creek networks). The analysis of broad-scale and fine-scale
patterns of occurrence also suggests new habitat nomenclature. Elevation-based terms (“low,”“middle,” and “high” marsh) should
be replaced by a system that considers elevation, landscape position, and conspicuous species. We suggest three habitat designations:
(a) the high marsh—a 30- to 70-cm elevation range with Salicornia subterminalis; (b) the marsh plain—a 30-cm elevation range with heterogeneous topography and up to nine common species; and (c) cordgrass habitat—the bayward portion of the marsh plain and lower elevations, all occupied by Spartina foliosa. Although these habitats do not have discrete boundaries, separate terms are needed for wetland restoration plans and these
designations will improve recognition that vegetation patterns respond to horizontal, as well as vertical, position. 相似文献
15.
Johnson CN 《Journal of the history of biology》2007,40(3):529-556
Almost any modern reader’s first encounter with Darwin’s writing is likely to be the “Historical Sketch,” inserted by Darwin
as a preface to an early edition of the Origin of Species, and having since then appeared as the preface to every edition after the second English edition. The Sketch was intended
by him to serve as a short “history of opinion” on the species question before he presented his own theory in the Origin proper. But the provenance of the “Historical Sketch” is somewhat obscure. Some things are known about its production, such
as when it first appeared and what changes were made to it between its first appearance in 1860 and its final form, for the
fourth English edition, in 1866. But how it evolved in Darwin’s mind, why he wrote it at all, and what he thought he was accomplishing
by prefacing it to the Origin remain questions that have not been carefully addressed in the scholarly literature on Darwin. I attempt to show that Darwin’s
various statements about the “Historical Sketch,” made primarily to several of his correspondents between 1856 and 1860, are
somewhat in conflict with one another, thus making problematic a satisfactory interpretation of how, when, and why the Sketch
came to be. I also suggest some probable resolutions to the several difficulties.
How Darwin came to settle on the title “Historical Sketch” for the Preface to the Origin is not certain, but a guess may be ventured. When he first submitted the text to Asa Gray in February 1860 he called it simply
“Preface Contributed by the Author to this American Edition” (Burkhardt et al., eds., vol. 8, 1993, p. 572; the collected
correspondence is hereafter cited as CCD). In fact he had thought of it as being properly called a Preface much earlier, perhaps as early as 1856, as will be seen
in what follows. It came to be called “An Historical Sketch of the Recent Progress of Opinion on the Origin of Species” only
in the third English edition, April 1861. This is the title it retained thereafter, with the exception of an addition to the
title in the sixth English edition, “Previously to the Publication of the First Edition of this Work” (Peckham, 1959, pp. 20, 59). The word “sketch,” on the other hand was one of two words Darwin commonly used in private correspondence to
refer to the book that would later become the Origin, the other word being “Abstract,” and both signifying that Darwin thought of the work as being a resume rather than a full-fledged
study (e.g., letter to J.D. Hooker, May 9 1856, CCD vol. 6 p. 106; letter to Baden Powell January 18 1860, CCD vol. 8 p. 41; letter to Lyell 25 June 1858, CCD v. 7, 1991, pp. 117–8; letter to Lyell May 1856, CCD, v. 6 p. 100). The most likely source of the title “Historical Sketch” for Darwin’s Preface is Charles Lyell’s Principles of Geology in which, beginning with the third edition (1834), Lyell added titles to his chapters, calling chapters 2–4 “Historical Sketch
of the Progress of Geology” (Secord, in Lyell [1997], p. xlvii; for other uses by Lyell of this expression, cf. Porter, 1976, p. 95; idem 1982, p. 38; and Lyell, 1830 [1990], p. 30). Further parallels between Lyell’s Introduction and Darwin’s “Historical Sketch” in terms of content and strategy
are suggested below. 相似文献
16.
Eukaryotic cells generally function in a reduced state, but an amount of reactive species is essential for several biochemical
processes. The antioxidant network is the defensive mechanism that occurs when the concentration of reactive species exceeds
a threshold. Polyphenolic compounds present in plant extracts are potent antioxidants in vitro, but they may promote oxidative
stress when administered in animals and humans, especially when given as supplements in exercise, a modality usually adopted
as an oxidant stimulus. This is mainly observed when antioxidant molecules are administered separately and not as part of
a diet. Exercise is usually adopted as a physiological model for examining the effects of reactive species in human or animal
physiology. The use of exercise as a model demonstrates that reactive species do not always have adverse effects, but are
necessary in physiological processes that are beneficial for human health. This review summarizes what is known about antioxidant
supplementation and demonstrates the need for a meticulous examination of the in vitro findings before applying them to in
vivo models. The term “antioxidant” seems elusive, and it is more appropriate to characterize a compound as “antioxidant”
if we know in which concentration it is used, when it is used, and under which conditions. 相似文献
17.
A new species Dolichopteryx minuscula is described on the basis of three specimens [49.4–59.6 mm in standard length (SL)] collected from the Indo-West Pacific.
The new species is characterized by pouchlike eyes with a small lens (lens diameter 2.2% SL), an adipose fin, the anal fin
base originating posterior to the dorsal fin base, and 16–17 (= 5–6 + 1 + 10–11) gill rakers. Total fecundity was relatively
low, only 658 ova being obtained from one specimen, despite the ovary being mature. Ovarian eggs were clearly subdivided into
“undeveloped” (0.1–0.7 mm diameter classes, n = 561) and “developed” (1.0–1.3 mm classes, n = 97) groups, based on their frequency distribution. Such relatively low fecundity and frequency distributions of ovarian
eggs suggest that Dolichopteryx species spawn iteratively during spawning season. 相似文献
18.
New species of Pogonophryne (Pisces, Artedidraconidae) from the Bellingshausen Sea, Antarctica 总被引:1,自引:1,他引:0
A new species of notothenioid fish, Pogonophryne bellingshausenensis n. sp., is described from the Bellingshausen Sea, Antarctica. The new species belongs to the dorsally-spotted “mentella”
group of the genus and is characterized by having a short (about 13% SL) mental barbel with a short (about 16% of barbel length),
narrow (barely wider than the stalk), and relatively inconspicuous terminal expansion composed of short, irregular, fingerlike
processes. Compared to most other dorsally-spotted species of Pogonophryne (“barsukovi”, “marmorata”, and “mentella” groups), P. bellingshausenensis has a relatively wide (about 7% SL) interorbital region. An unspotted patch on the median dorsal surface of the head, posterior
to the posttemporal ridges and anterior to the first dorsal fin, has not been observed previously in any dorsally-spotted
species. The holotype was collected at 1,947 m, one of the deepest records for any species of Pogonophryne. A revised key to the ten species of the “mentella” group of Pogonophryne is also provided. 相似文献
19.
Chiara Angelone 《Pal?ontologische Zeitschrift》2009,83(1):67-75
Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern
Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different
species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental
Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude
any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of
European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.
相似文献
20.
The future status of sharks is an issue of widespread conservation concern due to declines in many species in the face of
high levels of exploitation to satisfy market demands for products, especially fins. Substantial declines in the large-bodied
hammerhead sharks, Sphyrna lewini, S. mokarran and S. zygaena, even in regions where some management occurs, indicate that informed conservation measures are warranted for these circumglobally
distributed species. Despite the importance of assessing shark catch and trade on a species-specific basis to detect potential
overexploitation of individual species, achieving this goal for hammerheads has proven elusive due to difficulties in identification
of their products. Here, we present the development and application of a diagnostic, streamlined, five-primer multiplex polymerase
chain reaction assay utilizing species-specific primers based on nuclear ribosomal ITS2 for the three hammerhead species throughout
their global distribution. Application of this assay to investigations of the fin market confirmed the presence of hammerhead
fins in the international trade. A study of the world’s largest fin market in Hong Kong revealed a high concordance between
specific Chinese-name trade categories and fins from these three species (“Bai Chun” with S. lewini, “Gui Chun” with S. zygaena and “Gu Pian” with S.␣mokarran), and clear species preferences. This concordance information allows the use of market records for monitoring species-specific
trends in trade and exploitation rates. The assay is also proving useful for identification of shark body parts in U.S. fisheries
law-enforcement activities. Screening of morphologically identified “ S. lewini” from globally distributed areas using this assay with subsequent whole ITS2 sequencing suggests a cryptic species closely
related to S. lewini occurs off the SE USA coast. 相似文献