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Martha L. Bohórquez Alonso Jorge Martínez Cotrina David Aguilar Pardo Enrique Font Miguel Molina-Borja 《Journal of Ethology》2010,28(2):305-311
Many vertebrate species show display behaviors when predators are in their vicinity. Some of these displays may inform the
predator of the improbability of capturing the prey (i.e., pursuit-deterrent displays) and are potentially advantageous to
both predator and prey. Here we present data on a tail display performed by Gonatodes albogularis, a diurnal tropical gecko. We performed transect surveys in three habitats near Bogotá in Colombia. Geckos detected during
transects were approached by the observer in a standardized way, and details of their tail-waving displays were recorded.
In control recordings animals were watched from a distant site without approaching them. Results showed sexual differences
in tail-waving display: when approached by the observer, males performed this behavior more frequently than females. We found
no significant differences between males and females in flight-initiation distances and height above the substratum when they
were initially located. Results also showed that males displayed more frequently when approached than when the simulated predator
remained stationary. We interpret these results as evidence that the display functions as a pursuit-deterrent signal to potential
predators. However, as some tail displays were performed in the presence of conspecifics, the display may also have a social
function. 相似文献
14.
We evaluated the performance of Coptera haywardi (Ogloblin) (Diapriidae) and Pachycrepoideus vindemiae (Rondani) (Pteromalidae), both hymenopteran pupal parasitoids of Anastrepha spp. (Diptera: Tephritidae). Performance was studied by manipulating the following environmental conditions in the laboratory: (1) soil type, (2) soil moisture content, (3) soil compaction, and (4) depth at which pupae were buried in the soil. There were two experiments: in the first, exposure time of pupae was held constant and in the second, it varied. In the first experiment, C. haywardi was significantly more effective than P. vindemiae in parasitizing fly pupae. With exposure time held constant (36 h), only soil type and pupal burial depth were significantly related to parasitism rates. While P. vindemiae only parasitized pupae located on the soil surface, C. haywardi attacked pupae that were buried up to 5 cm deep, performing better in clayey than in loamy soil. In the second experiment, exposure time (24, 36, 48, and 72 h) had no significant effect on parasitism rates, but soil type did. P. vindemiae again only attacked pupae on the soil surface while C. haywardi was also able to parasitize pupae that were buried up to 5 cm deep. We conclude that C. haywardi represents a viable candidate to replace the environmentally unfriendly P. vindemiae in augmentative biological control programs against fruit flies. 相似文献
15.
Miguel Archangelsky 《Systematic Entomology》2004,29(2):188-214
Abstract. A phylogenetic analysis, at a tribal and subtribal level, of the subfamily Hydrophilinae was conducted. The analysis was based on twenty-nine taxa (twenty-three genera) and 148 characters (fifty-eight from immature stages and bionomics, and ninety from adults). According to the present study, Hydrophilinae is monophyletic, and except for the tribe Hydrophilini which appears as polyphyletic (it includes the subtribes Hydrophilina, Hydrobiina, and Acidocerina), the remaining tribes are monophyletic. The tribes Berosini and Chaetarthriini form the basal clade of Hydrophilinae. One unexpected result is the relationship between the subtribe Hydrobiina and the tribe Sperchopsini, which form a well-supported clade. The final tree has the following structure: (((((Sperchopsini Hydrobiina) (Anacaenini Laccobiini)) Acidocerina) Hydrophilina) (Berosini Chaetarthriini)). The results partially disagree with the phylogeny presented by Hansen, in 1991, which was based mostly on adult characters. Several evolutionary trends are briefly discussed: the types of egg case, the morphology of the clypeolabrum, mouthparts, legs, and breathing adaptations in larvae. 相似文献
16.
A rapid extraction method for screening aflatoxin producing potential ofAspergillus flavus group isolates is described. The method is performed using a moist wheat medium with ca. five infected grains extracted with 2 mL of chloroform, and using thin layer chromatography. This method was proved with 95A. flavus isolates from animal feeds. 相似文献
17.
To produce many small or few large eggs: a size-independent reproductive tactic of fish 总被引:2,自引:2,他引:0
Summary We demonstrate here the existence of a range of size-independent reproductive tactics in teleostean fish involving the allocation of a size-dependent reproductive effort between fecundity and egg size. Despite considerable evidence that larger eggs and the larvae hatching from them are more likely to survive than smaller ones, we found no evidence of evolutionary trends towards greater egg sizes. Fish with pelagic eggs tend to spawn many, and therefore small, eggs, whereas demersal spawners tend to produce large, and therefore few, eggs. Maximizing egg number should increase the number of eggs hatching in suitable locations in the patchy pelagic environment and, hence, increase the reproductive success of pelagic spawners. On the other hand, the reproductive success of demersal spawners, which reduce the variance in growing conditions experienced by the off spring, should be more dependent on the survival of the individual larvae, which increases as egg size increases. 相似文献
18.
Summary Germination of condiospores fromA.niger in very concentrated suspension was required to inoculate solid fermentation media, but a germination self-inhibitor was detected in spores. It was found that the inhibitory effect depended on the composition of the medium and was reduced when glucose was used as a carbon source. The effect of the self-inhibitor was eliminated by washing the spores and using glucose and a protein nitrogen source in the germination medium. By this method it was possible to increase about 100 times (106 to 108) spore concentration, keeping more than 90% germination. 相似文献
19.
Jens Ewers Miguel Angel Rubio Hans-Joachim Knackmuss Doris Freier-Schrder 《Applied microbiology》1989,55(11):2904-2908
Strain DM1, a Mycobacterium sp. that utilizes 2,6-xylenol, 2,3,6-trimethylphenol, and o-cresol as sources of carbon and energy, was isolated. Intact cells of Mycobacterium strain DM1 grown with 2,6-xylenol cooxidized 2,4,6-trimethylphenol to 2,4,6-trimethylresorcinol. 4-Chloro-3,5-dimethylphenol prevents 2,6-xylenol from being totally degraded; it was quantitatively converted to 2,6-dimethylhydroquinone by resting cells. 2,6-Dimethylhydroquinone, citraconate, and an unidentified metabolite were detected as products of 2,6-xylenol oxidation in cells that were partially inactivated by EDTA. Under oxygen limitation, 2,6-dimethylhy-droquinone, citraconate, and an unidentified metabolite were released during 2,6-xylenol turnover by resting cells. Cell extracts of 2,6-xylenol-grown cells contained a 2,6-dimethylhydroquinone-converting enzyme. When supplemented with NADH, cell extracts catalyzed the reduction of 2,6-dimethyl-3-hydroxyquinone to 2,6-dimethyl-3-hydroxyhydroquinone. Since a citraconase was also demonstrated in cell extracts, a new metabolic pathway with 2,6-dimethyl-3-hydroxyhydroquinone as the ring fission substrate is proposed. 相似文献
20.
Comparison between intra- and extracellular surfactant in respiratory distress induced by oleic acid 总被引:1,自引:0,他引:1
C Casals L Herrera E Miguel P Garcia-Barreno A M Municio 《Biochimica et biophysica acta》1989,1003(2):201-203
The present study compares the phospholipid distribution and protein content in bronchoalveolar lavage, purified extracellular surfactant and lamellar bodies isolated from rabbits killed at intervals of 2.5, 12 and 24 h after oleic acid administration. The data suggest that the alteration of pulmonary surfactant could be partially due to the type II cell response to the injury. 相似文献