Very comprehensive. Overall they seem to alternate the chapters so the topics feel a bit varied, alternating the more technical chapters with more fauna/ecosystem heavy chapters - I feel like 85% of stuff was familiar honestly from just reading news articles and watching lots of documentaries over the years, and going to aquariums a lot, but learned more about the interplay of plankton, benthic substrata, etc and the many variables that come into play to create certain systems -