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To investigate the e¡ects of body size and water temperature on feeding and growth in the sea cucumber Apostichopus japonicus (Selenka), the maximum rate of food consumption in terms of energy (C maxe ; J day À1 ) and the speci¢c growth rate in terms of energy (SGRe; % day À1 ) in animals of three body sizes (mean AE SE)^large (134.0 AE 3.5 g), medium (73.6 AE 2.2 g) and small (36.5 AE 1.2 g)^were determined at water temperatures of 10, 15, 20, 25 and 30 1C. Maximum rate of food consumption in terms of energy increased and SGRe decreased with increasing body weight at 10, 15 and 20 1C. This trend, however, was not apparent at 25 and 30 1C, which could be in£uenced by aestivation. High water temperatures (above 20 1C) were disadvantageous to feeding and growth of this animal; SGRe of A. japonicus during aestivation was negative. The optimum temperatures for food consumption and for growth were similar and were between 14 and 15 1C, and body size seemed to have a slight e¡ect on the optimal temperature for food consumption or growth. Because aestivation of A. japonicus was temperature dependent, the present paper also documented the threshold temperatures to aestivation as indicated by feeding cessation. Deduced from daily food consumption of individuals, the threshold temperature to aestivation for large and medium animals (73.3^139.3 g) was 24.5 À25.5 1C, while that for small animals (28.94 0.7 g) was between 25.5 and 30.5 1C. These values are higher than previous reports; di¡erences in sign of aestivation, experimental condition and dwelling district of test animals could be the reasons.

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Mutation of a small noncoding RNA drives adaptive evolution in a social bacterium.

There is significant commercial and research interest in the application of sea cucumbers as nutrient recyclers and processors of particulate waste in polyculture or integrated multitrophic aquaculture (IMTA) systems. The following article reviews examples of existing IMTA systems operating with sea cucumbers, and details the role and effect of several sea cucumber species in experimental and pilot IMTA systems worldwide. Historical observations and quantification of impacts of sea cucumber deposit-feeding and locomotion are examined, as is the development and testing of concepts for the application of sea cucumbers in sediment remediation and site recovery. The extension of applied IMTA systems is reported, from basic piloting through to economically viable farming systems operating at commercial scales. The near-global recognition of the ecological and economic value of deposit-feeding sea cucumbers in IMTA applications within existing and developing aquaculture industries is discussed. Predictions and recommendations are offered for optimal development of sea cucumber IMTA globally. Future directions within the industry are indicated, and key areas of ecological, biological and commercial concern are highlighted to be kept in mind and addressed in a precautionary manner as the industry develops.

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