, Volume 21, Issue 12, pp 1931-1946

Natural variation of toxicity in encrusting spongeCrambe crambe (Schmidt) in relation to size and environment

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


The presence of intraspecific variation in toxicity and its relationship with biological or ecological factors were studied in the spongeCrambe crambe. Within-specimen (periphery and central part), between-size (<1000 mm2 in area, between 1000 and 10,000 mm2 and >10,000 mm2) and between-habitat (well-illuminated and dark communities) variations in toxicity were evaluated by the Microtox bioassay. Quantitative differences were detected that were not attributable to within-specimen variation but to size and habitat effects. Habitat comparisons showed that sponges in the shaded habitat were significantly more toxic than those of the well-illuminated community. Sponges of the smaller size classes displayed significantly less toxicity than the medium-sized specimens. Results are interpreted under the optimal defense theory and their ecological implications are considered.