In response of environmental challenges, microbes develop appropriate responses and behaviors which include chemotaxis. Some marine bacteria in particular, inhabit environments devoid of nutrients. To survive, they are able to move towards more favourable niches by a mechanism called chemotaxis wherein substrates are detected using chemoreceptors. A chemotactic assay enabling the rapid test of several hundreds of different solutes and identifying several molecules eliciting a chemotactic response in two aquatic Shewanella species was developed (Armitano et al., 2011). The environment is rarely constant and organisms are exposed to spatial and temporal variation, microorganisms may rapidly evolve and acquire original characteristics when they face unique or multiple. One report by Duncan et al. (2011) explores how patterns of local adaptation of the ciliate Paramecium caudatum are affected when this organism is exposed to constant (23 C or 35 C) and temporally variable temperature environments (random
daily fluctuations between 23 C or 35 C). The authors observed that specialists are locally adapted through reduced fitness in novel environments. Conversely, the generalists had equal or superior performance to specialists. The lack of a cost for generalists is emphasised by the presence of a super generalist that has the highest performance at both assay temperatures
In response of environmental challenges, microbes develop appropriate responses and behaviors which include chemotaxis. Some marine bacteria in particular, inhabit environments devoid of nutrients. To survive, they are able to move towards more favourable niches by a mechanism called chemotaxis wherein substrates are detected using chemoreceptors. A chemotactic assay enabling the rapid test of several hundreds of different solutes and identifying several molecules eliciting a chemotactic response in two aquatic Shewanella species was developed (Armitano et al., 2011). The environment is rarely constant and organisms are exposed to spatial and temporal variation, microorganisms may rapidly evolve and acquire original characteristics when they face unique or multiple. One report by Duncan et al. (2011) explores how patterns of local adaptation of the ciliate Paramecium caudatum are affected when this organism is exposed to constant (23 C or 35 C) and temporally variable temperature environments (randomdaily fluctuations between 23 C or 35 C). The authors observed that specialists are locally adapted through reduced fitness in novel environments. Conversely, the generalists had equal or superior performance to specialists. The lack of a cost for generalists is emphasised by the presence of a super generalist that has the highest performance at both assay temperatures
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