Interspecific interactions

Basidiomycetes and ascomycetes Intraspecific population interactions Interspecific interactions... 

Atchison, G.J., Sandheinrich, M.B., and Bryan, M.D. (1996). Effects of environmental stressors on interspecific interactions of aquatic animals. In M.C. Newman and C.H. Jagoe (Eds.), Quantitative Ecotoxicology A Hierarchical Approach. Lewis, Chelsea, Ml. 

Nordlund, D.A. and Lewis W.J. (1976) Terminology of chemical releasing stimuli in intraspecific and interspecific interactions. J. Chem. Ecol. 2, 211-220. 

Pohnert G, Steinke M, Tollrian R (2007) Chemical cues, defence metabolites and the shaping of pelagic interspecific interactions. Trends Ecol Evol 22 198-204 Prince EK, Lettieri L, McCurdy KJ, Kubanek J (2006) Fitness consequences for copepods feeding on a red tide dinoflagellate deciphering the effects of nutritional value, toxicity, and feeding behavior. Oecologia 147 479 188... 

Environmental odors can also play a role in interspecific interactions such as preying. The domestic dog uses cues from disturbed soil and crushed plants when tracking and they can be trained to follow tracks that lack scent. When following a scent, such as a human track, they can be diverted by another scent crossing the first pathway. The choice made by the dog is influenced by the odors and cues available at any point (Most and Bruckner, 1936 see p. 414). 

Wetzel, R. G. 1991. Extracellular enzymatic interactions in aquatic ecosystems Storage, redistribution and interspecific communication. In Microbial Enzymes in Aquatic Environments (R. J. Chrost, Ed.), pp. 25-59. Springer-Verlag, New York. 

Hairston, N. G., Jr., and N. G. Hairston. 1993. Cause-effect relationships in energy flow, trophic structure, and interspecific interactions. American Naturalist 142 379-411. 

The external cuticle of insects is covered by a waxy layer composed of mixtures of hydro-phobic lipids that include long-chain alkanes, alkenes, wax esters, fatty acids, alcohols, aldehydes, and sterols. The primary purpose of this layer is to maintain water balance and prevent desiccation, as described in Chapter 6, but many of the cuticular lipid components have important secondary roles as intraspecific contact chemical signals (pheromones). These roles include species and sex recognition during reproductive interactions, and nestmate recognition and other colony organization functions in social insects. Thus, these compounds are essential mediators of insect behaviors. Cuticular compounds are also exploited by parasitoids and predators as interspecific contact cues (kairomones) to aid in host location. 

For a variety of reasons, some of which have already been discussed, we can often learn more about a communication system by studying the pheromones and related behavior of several members of a genus or family than by an in-depth study of a single species. The Interspecific interactions are often quite subtle but very important. For example, the importance of enantiomers or stereoisomers may only become evident after investigating the responses of several closely related species to a pheromone or pheromone blend. 

A wide variety of activities have been demonstrated for the alkaloids identified in myrmecine ant venoms, indicating that these small nitrogen heterocycles have been adapted to subserve multiple functions. Both the piperidines and pyrrolidines possess diverse pharmacological activities (reviewed in 1), and it seems likely that their roles in regulating both intra- and interspecific interactions are very significant. 

Dighton Boddy, 1989), but loss can occur during interspecific interactions (J. M. Wells L. Boddy, unpublished), and as a result of invertebrate grazing (Anderson et ah, 1983). 

The purpose of this experiment is to examine the role of ants in the life of aphids. Although chemical stimuli play an important role in their interactions, here we focus on the results of these interspecific behaviors. Nevertheless, the observer can try to gently touch an aphid with a pair of fine tweezers and observe the responses of ants and other aphids over a distance, presumably in response to an alarm odor. 

Not only are there scales in organization, but scales over space and time exist. It is crucial to note that all of the functions described in previous sections act at a variety of spatial and temporal scales (Suter and Bamthouse 1993). Although in many instances these scales appear disconnected, they are in fact intimately intertwined. Effects at the molecular level have ecosystem level effects. Conversely, impacts on a broad scale affect the very sequence of the genetic material as evolution occurs in response to the changes in toxicant concentrations or interspecific interactions. 

An implicit assumption of the MFC is that the acclimation time is sufficient for coevolution to occur and that coevolution is important to assess the impacts of xenobiotics upon communities. The use of a "natural" inocula should increase species diversity and complexity over a protocol such as the SAM, but the smaller size of the test vessel would tend to decrease species number. Debate also exists as to the applicability of coevolution in the evaluation of test chemicals. If algal populations and others are primarily regulated by density-independent factors, then population-specific interspecific interactions may not be particularly important. If ecosystems are loosely connected in an ecological sense, coevolved assemblages may be rare. On the other hand, in enclosed systems that are islands, these relationships may have had an opportunity to occur, and coevolved interactions may be important in the assessment of toxicological impacts. 

Hanski, L, 1997. Predictive and practical metapopulation models the incidence function approach, in Spatial Ecology The Role of Space in Population Dynamics and Interspecific Interactions, Tilman, D. and Kareiva, P., Eds., Princeton University Press, Princeton, NJ, pp. 21-45. 

Semiochemicals can be placed into two distinct classes Pheromones control intraspecific interactions. These semiochemicals provide information regarding a range of behaviours including mate selection, aggregation, dispersal (alarm pheromones), oviposition and food sources (trail pheromones). Allelochemicals control interspecific interactions such as host and non-host identification by primary colonizers (plant or animal) and whether a food source is already exploited through tritrophic interactions (signals indicating the presence of primary colonizers). 

Although the final structures of CFs are unresolved, our results support the working hypothesis that at least two interacting factors must be involved in the conditioning processes and that various plant species can produce different CFs with interspecific activity. 

The model describes a three level vertical food-chain, where the resource or vegetation u is consumed by herbivores u, which in turn are prey on by top predators w. The parameters a, b and c represent the respective growth rates of each species in the absence of interspecific interactions (fci = fc2 = 0). The functions fi x,y) describe interactions between... 

The improvement in experimental facilities, often related to a direct economic interest, has led to an increase in studies on the interactions between marine animals involving chemical substances. A number of taxonomic groups have been studied as a result of this interest. It has become classical to consider separately the intra-specific interactions or regulations, which strongly influence the sexual biology and the social evolution of numerous species, and the interspecific or trans-specific interactions within the dynamic equilibrium of biocoenoses. Although arbitrary on many points, this clear differentiation has the merit of facilitating analysis of data in the literature. 

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