Interaction intraspecific

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

Renaud PE, Hay ME, Schmitt TM (1990) Interactions of plant stress and herbivory intraspecific variation in the susceptibility of a palatable versus an unpalatable seaweed to sea urchin grazing. Oecologia 82 217-226... 

Attractive Compounds. Despite the fact that defence chemistry and insect-plant interactions have been extensively investigated in many leaf beetle species, not too much is known about the chemical background of intraspecific communication. 

Autointoxication, in which an organism releases a toxic chemical that suppresses its own growth, is one phase of allelopathy. Autointoxication can also be important in intraspecific interactions, such as the regulation of population size by self-thinning. Several case studies conducted in Taiwan are described below. 

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. 

Jackson, R.R. and Pollard, S.D. (1982). The biology of Dysdera crocata (Araneae Dysderidae) intraspecific interactions../. Zool., 198,197-214. 

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). 

This model generally takes into account the natural ecological model. The niche model proposed by Brush refers much to that of interspecies interaction that is only a part of this model and it explains only the crop introduction and enhancement aspects. Intraspecific competition is not indicated by the model, though it was suggested to be scaled down for inter-varietal competition. Inter-varietal competition that leads to a balance or imbalance in the specific niches is niche theory for GE but this is not sufficient. The assumptions of the classical models are easily violated in farming systems in the centre of diversity, so that we should expect co-existence rather than the competitive exclusion to prevail. Hence, the niche model does not completely explain the GE scenario. 

The most well-known functions of secondary metabolites among arthropods include the use of pheromones for intraspecific communication, the employment of antipredatorial defensive agents, and the offensive use of paralytic and/or toxic agents, such as in the form of venoms, for the acquisition of prey. In recent years, considerable insight has been gained in all three categories, as well as in the discovery of heretofore unknown interactions (see Section 2.04.4.1). Fossil evidence of chemical defense in the insects reaches as far back as the Early Cretaceous period. The chemical defense of insects has been reviewed as... 

It was pointed out above that "crowding" as I have used the term refers to an interspecific interaction but that biologists often use the term for an intraspecific interaction. The context will make it clear in most cases which kind of interaction is being referred to, so there should be no difficulty in using the same word for two different kinds of situations. 

As the variety of chemical interactions between organisms became better understood during the 1960s and 1970s, many authors attempted to classify the interactions and the chemical agents involved. If pheromones describe intraspecific signals, what terms should be used for interspecific chemical interactions In the recent aquatic chemosensory literature, authors seem to be almost equally divided between using semiochemicals and infochemicals. ... 

Most of what is known about crustacean chemoreception is in the context of food detection and ingestion only very little is known in other behavioral contexts, such as predator avoidance, orientation in the habitat, interactions with symbiotic partners, or intraspecific communication by pheromones. From recent behavioral and neuroanatomical studies, two important concepts about pheromone reception in crustaceans have emerged ... 

In this chapter, we review the ways whereby lobsters chemically communicate with each other and the contexts in which they do it. We make a distinction between different types of chemicals. Based on the terminology of Wyatt (Chap. 2), we use semiochemicals as chemicals involved in animal interactions and pheromones as a subset of semiochemicals used in intraspecific contexts. We also use cues as chemicals that benefit the receiver and not necessarily the sender, with a prime example being alarm cues released in the blood of injured conspecifics. 

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