Book Review - Seaweeds of the World: A Guide to Every Order - Princeton University Press

 

     The opening sentence in the Introduction states "Seaweeds rarely get the attention they deserve," and I think that speaks volumes about the relationship most of us have with seaweed. It is either slimy stuff left on the beach when the tide goes out, or wrapping on our sushi when we go to our favourite Japanese restaurant. 

     Seaweeds (algae) merit much more than this! They are the marine equivalent of terrestrial forests and other vegetational ecosystems, and are critically important in marine environments. Seaweeds are classifed in three phyla, Green (Chlorophyta), Red, (Rhodophyta) and Brown (Ochrophyta), each distinct in myriad important ways from the others.

     This excellent book demystifies seaweeds in so many different ways. It begins with the simple question, "What are seaweeds?" and moves us through a complete examination of these under-studied and under-appreciated organisms. As one moves from section to section - Early evolution, early multicellurality, a natural history - and so on, one acquires a fundamental understanding of the wide diversity of seaweeds and their importance, both ecological and commercial, in various parts of the world.

     In coastal areas, seaweeds form the basis of food webs, and anchor an ecosystem as diverse and vibrant as any land-based equivalent. As a nursery for marine organisms they are critical, and unrivalled in richness. ".....perhaps three quarters of Earth's fish start their lives in a seaweed bed." 

     As we continue to emit unsustainable levels of greenhouse gases like carbon dioxide and methane into the atmosphere we are changing the chemistry of the oceans, in some areas such as the Arctic at an alarming rate. Throughout the world oceans are becoming more acidic and drastic die-offs are occurring. The public is generally aware of the destruction of coral reefs, those glamourous ecosystems whose demise makes the nightly news, but little is reported on seaweed die-off and the potential for speciation. The results are no less catastrophic.

     We are now clearly into the Anthropocene, the human-made epoch, and threats to seaweeds are pressing and dire. To claim that it is terrifying would not be hyperbole. As the author states about threatened species, "So enjoy the ones we have while they are still with us."

     In the section entitled Selected Species seventy genera are covered, with pictures, range maps and a succinct informative text. This is such a valuable guide to seaweeds and of great benefit to scientist and layman alike. I have always made a practice of taking pictures of seaweed marooned by receding tides and I will look forward to being able to identify them with the help of this book.

     The great takeaway, perhaps, is that despite all the evidence at our disposal, humankind seems unwilling to seriously tackle the issue of climate change that threatens the ongoing survival of the planet as we know it. The science is clear, and we ignore it at our peril. Yet - ignore it we do. If rhetoric were action we would by now have solved the problem.

     Perhaps seaweeds are yet another canary in the coal mine. How many do we need?

Seaweeds of the World: A Guide to Every Order

John H. Bothwell

Hardcover - US$29.95 - ISBN: 9780691228549

240 pages - 6.75 x 9.375 inches (16.875 x 23.44 cm)

249 colour and 17 black-and-white illustrations - 77 maps

Publication date: 31 January, 2023