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51.
Christine Errard Abraham Hefetz Pierre Jaisson 《Behavioral ecology and sociobiology》2006,59(3):353-363
To investigate the role of template plasticity in shaping nest-mate recognition processes in ants, we constructed experimental
mixed-species groups of Manica rubida with either Myrmica rubra, Tetramorium bicarinatum or Formica selysi. Selecting Ma. rubida as the focal species, we observed the behaviour within mixed-species groups and the transfer rates of cuticular hydrocarbons
(CHC) onto the focal ants, and we also tested the aggression of the focal species reared either alone or in association with
each of the three different species. We show that Ma. rubida workers were always amicable towards their mixed group members, as towards members of the respective parental colonies, irrespective
of the associated species. They did, however, express different levels of aggression towards single-species groups of the
other species tested, depending on the species with which they were reared. The study suggests that similarity in CHC profiles
in two species leads to a narrow template in mixed groups, while dissimilarity is followed by lower levels of aggression (a
broader template), at least against species with similar CHC compound compositions (i.e. both a broader template in the focal
ants and familiarity with the compound groups of the tested individuals operate together). This refutes the hypothesis that
ants reared in mixed-species groups are systematically more tolerant. It also demonstrates that heterospecific information
is not treated equally during development. We suggest that post-imaginal learning, template reforming and decision making
are more precisely tuned when the two species' chemical complexes are similar. 相似文献
52.
C. Magdalena Wolf Brad Griffith Christine Reed Stanley A. Temple 《Conservation biology》1996,10(4):1142-1154
In 1993 we conducted a follow-up study of the 1987 survey by Griffith et al. (1989) of 421 avian and mammalian translocation programs in North America, Australia, and New Zealand to reassess the programs' status and the biological and methodological factors associated with success. Our survey response rate was 81%. Approximately 38% of usable programs in 1993 reported a change in outcome from 1987 (e.g., a translocated population was "declining" but now is "self-sustaining"), but the difference between the overall success rates was not statistically significant (66% in 1987 and 67% in 1993). Since 1987, an increase was observed in the median number of animals translocated per program (31.5 to 50.5), median duration of releases (2 to 3 years), and proportion of programs releasing more than 30 animals (46% to 68%). Multiple logistic regression analyses indicated that release into the core of the historical range, good-to-excellent habitat quality, native game species, greater numbers of released animals, and an omnivorous diet were positively associated with translocation success. Moreover, our results indicate that translocated birds were less successful at establishing self-sustaining populations than translocated mammals. Our findings, using comparable logistic analyses, generally corroborate the results of Grifftth et al. (1989). Variables not found to be significantly correlated with translocation success include species' reproductive potential (number of offspring and first age of reproduction), number and duration of the releases, and source of the translocated animals (wild-caught versus captive-reared). 相似文献
53.
Following uptake of technetium-95m and americium-241 by lobsters (Homarus gammarus) from food, the subcellular distribution and binding in the major organ of accumulation, the digestive gland, were analysed.95mTc was predominantly bound to soluble proteins; approximately 40% was bound to two proteins displaying the same elution characteristics as Cdthioneins as indicated by gel permeation and ion-exchange chromatography, indicating reduction and sequestration by metallothionein in vivo. The identity of a third anionic low molecular weight Tc-binding component was not established. No evidence was found for binding of Tc to haemocyanin, ferritin or transferrin. Particulate Tc [probably TcO(OH)2] was bound to plasma membranes and was also present in lysosomes, indicating reduction of pertechnetate and pinocytosis in the digestive gland. In contrast,241Am was mainly sequestered by the lysosomal/vacuolar system, indicative of uptake by pinocytosis. Approximately 2 to 3% of the Am was bound to ferritin and 20% was bound to unidentified ligands of 10 and 20 kdaltons mol. wt. There was no evidence for sequestration of Am by metallothionein. These studies prove that waste radionuclides discharged by the nuclear industry are metabolically active and enter the normal metal metabolism and detoxication pathways of a marine shellfish. 相似文献
54.
In French Guiana, parabiotic societies (natural mixed colonies) are frequently found in ant gardens. Crematogaster limata parabiotica (Myrmicinae), often associated with Camponotus femoratus (Formicinae), was found for the first time in parabiosis with ponerine ants: Pachycondyla goeldii and Odontomachus mayi. A detailed study of the relationships between Cr. l. parabiotica and O. mayi showed that each species is aggressive towards allospecific or conspecific individuals belonging to another colony, but tolerates
allospecific individuals from the multi-species society. Studies of cuticular substances of the four ant species were made
using gas chromatography. The results showed that each species, living alone or in parabiosis, possesses a specific chemical
profile. Thus, the ants are able to recognise nestmate and non-nestmate individuals of the associated species, even though
their cuticular profiles are different. The hypothesis that the nestmate allospecific profile is learned is suggested to explain
this pattern of recognition.
Received: 5 June 1996 / Accepted after revision: 17 October 1996 相似文献
55.
Bob B. M. Wong Christine Bibeau Karen A. Bishop Gil G. Rosenthal 《Behavioral ecology and sociobiology》2005,58(4):345-350
Prey require information if they are to respond to predation threat in a risk-sensitive manner. One way that individuals can obtain this information is through the predator-mediated, threat-induced behavior of conspecifics. We examined such a possibility in a refuge-seeking species, the sand fiddler crab (Uca pugilator). Crabs were either exposed directly to a simulated predation threat (a moving cylinder) or the threat-induced response of a near neighbor. We found that fiddler crabs responded to the flight of their neighbors even when they, themselves, were not privy to the stimulus that induced their neighbors response. However, the wider range of behaviors exhibited by these crabs—which included no reaction, freezing, running back to the burrow entrance, and burrow retreat—suggest that non-threatened crabs either (1) perceived the gravity of the predation threat differently from their directly threatened neighbors and/or (2) engaged in behaviors that allowed them to acquire further information in the face of uncertainty. Conspecific behaviors also had an effect on the hiding duration of crabs, with individuals hiding longer if they saw both the predation threat and the flight of their neighbor. Our results suggest that cues provided by conspecifics can play an important role in guiding the antipredator response of refuge-seeking prey. 相似文献
56.
Potential allelopathic effect of Pinus halepensis in the secondary succession: an experimental approach 总被引:1,自引:0,他引:1
Catherine Fernandez Benjamin Lelong Bruno Vila Jean-Philippe Mévy Christine Robles Stéphane Greff Sylvie Dupouyet Anne Bousquet-Mélou 《Chemoecology》2006,16(2):97-105
Summary. Recent economic and social changes in north Mediterranean regions have led to an important rural depopulation. Consequently,
meadows developed on abandoned agricultural lands (characterized by high species richness) undergo reforestation. These former
fields are mainly colonized by Pinus halepensis Miller, which is known to synthetize a wide range of secondary metabolites, among these, some could influence plant succession
through allelopathy. The allelopathic potential of P. halepensis, was tested against two target species (Lactuca sativa L. and Linum strictum L.) with aqueous extracts obtained from different organs (root and needle) taking into account the individual age (±10, ±30
and > 60 years old). Root and needle extracts affected differently germination and growth of the two target species, the responses
varying with concentration of extracts, age and organs tested. The strongest inhibitory effect was observed on the germination
and growth of L. strictum, exposed to needle extracts of young P. halepensis (±10 years old), and root extracts of older P. halepensis (> 30 years old). These extracts contained several phenolic acids (e.g. 4-hydroxybenzoic acid and p-coumaric acid), which are known as allelochemicals and their concentrations vary with age and
organ tested. Hence, P. halepensis could influence secondary succession through the release of potential allelochemicals in the environment by leaf leachates
or root exudates. 相似文献
57.
Frédéric Mineur Mark P. Johnson Christine A. Maggs Herre Stegenga 《Marine Biology》2007,151(4):1299-1307
Hull fouling is thought to have been the vector of introduction for many algal species. We studied ships arriving at a Mediterranean
harbour to clarify the present role of commercial cargo shipping in algal introductions. A total of 31 macroalgal taxa were
identified from 22 sampled hulls. The majority of records (58%) were of species with a known cosmopolitan geographical distribution.
Due to a prevalence of cosmopolitan species and a high turnover of fouling communities, species composition of assemblages
did not appear to be influenced by the area of origin, length of ship or age of coating. In the light of the present results,
hull fouling on standard trading commercial vessels does not seem to pose a significant risk for new macroalgal species introductions.
However, a high proportion of non-cosmopolitan species found on a ship with non-toxic coating may modify this assessment,
especially in the light of the increasing use of such coatings and the potential future changes in shipping routes. 相似文献
58.
Franois Oehler Paul Bordenave Patrick Durand 《Agriculture, ecosystems & environment》2007,120(2-4):313-324
We measured denitrification at 15 sites during 1 year in a agricultural catchment in Brittany, France. Our objective was to assess the relative importance of heterotrophic denitrification on the fate of excess nitrogen at the catchment scale, and to quantify the relative importance of riparian areas on the N2O emissions. Using the C2H2 inhibition technique, denitrification rate on soil core and denitrifying enzyme activity (DEA) were each determined, for samples taken from two soil layers: 0–20 and 20–40 cm. Denitrification rates, ranging from 0 to 417 mg N m−2 d−1, were significantly higher in riparian areas than for hillslopes (median of 24.87 against 10.38 mg N m−2 d−1). However, since denitrification rates are significant in the hillslope and given that hillslope surface area is much greater (79% of catchment surface), this domain could be responsible for half of the overall denitrified nitrogen (N). Also, the 20–40 cm deep soil layer was found to account for more than 46% of the denitrification. The DEA indicates the potential for denitrifying activity by the soil under non-limiting conditions, measured values ranged from 76.48 to 530.63 ng N g−1 dry soil h−1. The ratio N2O/(N2O + N2) was about 60% with no clear spatial or temporal trends. Soil moisture appeared to be the main limiting factor for denitrification at the field scale. The results suggest that, for this catchment, denitrification is a major route for nitrogen removal, but a significant proportion of this removal occurs as N2O. 相似文献
59.
The control of disinfection by-products during water treatment is primarily undertaken by reducing the levels of precursor species prior to chlorination. As many waters contain natural organic matter at levels of up to 15 mgl(-1) there is a need for a range of control methods to support conventional coagulation. Two such processes are the Fenton and photo-Fenton's processes and in this paper they are assessed for their potential to remove NOM from organic rich waters. The performance of both processes is shown to be depentent on pH, Fe: H2O2 ratio as well as Fe2+ dose. Under optimum conditions both processes achieved greater than 90% removal of DOC and UV254 absorbance. This removal lead to the trihalomethane formation potential of the water being reduced from 140 to below 10 microgl(-1), well below UK and US standards. 相似文献
60.
Durand C Ruban V Amblès A Oudot J 《Environmental pollution (Barking, Essex : 1987)》2004,132(3):375-384
This paper presents the results of the organic matter characterization of sludge from two ponds (retention and infiltration) located in France. Special focus was placed on studying hydrocarbons and PAHs. This investigation is part of a global project on road and urban sludge with the aim of identifying a better means for managing these materials. Gas chromatographic and GC/MS analyses indicate that the main component of the organic fraction stems from petroleum-derived products like diesel fuel and motor oil. This finding was confirmed by the presence of biomarkers from the hopane series, as well as by pyrolytic and alkylated PAHs. Results from this study clearly show that the contaminants are mainly generated from anthropogenic petroleum sources. Due to their levels of hydrocarbon contamination, these sludge deposits must be considered as waste and cannot therefore be disposed anywhere, especially within the current context of sustainable development. 相似文献