“Extreme” anything makes for a good selling title these days: a symptom of our jaded consumerist palates. But The Extreme Life of the Sea – that’s another matter. There’s nothing forced about these creatures: they just exist, innocently, doing what they have to do. Stephen and Anthony Palumbi – father and son; biologist and science writer – are brilliant guides to this realm about which we as a species have been remarkably incurious.
There have been exceptions. Darwin, one of the most enquiring men who ever lived, puzzled at the enormous creatures that live in the apparently empty oceans. What on earth sustains them? My oceanography bible has always been Sir Alister Hardy’s classic two volumes on The Open Sea (1956; 1959). From this I learnt about the photosynthesizing microplankton at the bottom of the food chain and the krill that feed on them, in turn being food for the largest whales such as the Blue. But we know so much more now. The Palumbis père et fils give us the new stories in succinct prose beautifully freighted with apt similes and metaphors: the Blackfin icefish (whose environmentally friendly antifreeze proteins have been cloned and used in our ice cream) has prominent lips, “making them look like moustachioed RAF pilots”; in the patterns on the clownfish, “Nature holds a seminar on graphic design”.
The greatest revelation of recent research is that the ocean is dominated not by its giants but by its microflora and fauna: bacteria and viruses, its primary producers. We harvest about 88 million tonnes of fish and shellfish annually; the ocean’s microbes produce this amount of biomass in about one hour. This is the missing link in those supposedly “empty” oceans that baffled Darwin.
A feature of life under water is the longevity of some of the creatures: it is oxygen that both sustains and limits the span of animal life and there is much much less of it underwater. Turtles can live to over 200 years, some fishes manage 100 plus and there is even an immortal: the Turritopsis jellyfish which, if stressed, can dissolve itself back to the larval form and start all over again.
The extreme deep conjures a picture of eternal dark and menacingly ugly and odd creatures. This is partly true but it isn’t uniformly pitch black thanks to bioluminescence: living light generated by enzymes. Most of the light is blue-green and that is all most creatures can perceive but one fish can generate and see red light. It goes its way with a secret torch nothing else can observe: in the kingdom of the blind-to-red, the Stoplight loosejaw is king.
The oceans are our future and it is here that the drama of climate change will play out with the greatest consequences: if we destroy their ecosystems we will lose more than the food they provide. The complacent attitude excoriated by Philip Larkin in the poem ‘Going Going’ – “Chuck filth in the sea . . . The tides will be clean beyond” – is still too common. We need the Palumbis’ dazzling little book to put us right.
Peter Forbes and Tom Grimsey’s Nanoscience: Giants of the Infinitesimal will be published by Papadakis in May