Supplementary material from "Trapped DNA fragments in marine sponge specimens unveil North Atlantic deep-sea fish diversity"

Sponges pump water to filter feed and for diffusive oxygen uptake. In doing so, trace DNA fragments from a multitude of organisms living around them are trapped in their tissues. Here we show that the environmental DNA retrieved from archived marine sponge specimens can reconstruct the fish communities at the place of sampling and discriminate North Atlantic assemblages according to biogeographic region (from Western Greenland to Svalbard), depth habitat (80–1600 m), and even the level of protection in place. Given the cost associated with ocean biodiversity surveys, we argue that targeted and opportunistic sponge samples – as well as the specimens already stored in museums and other research collections – represent an invaluable trove of biodiversity information that can significantly extend the reach of ocean monitoring.Lay abstract. Sponges are animals that pump water to filter feed and to breathe. In doing so, trace DNA fragments from a multitude of organisms living around them are trapped in their tissues. Here we show that the environmental DNA retrieved from marine sponge specimens can reconstruct North Atlantic fish communities according to biogeographic region, depth, and even protection status. Given the high cost of marine biodiversity surveys, we argue that sponge samples—particularly the specimens already stored in museums and other research collections—represent an invaluable trove of biodiversity information that can significantly extend the reach of ocean monitoring.