Seeing is Believing: Diatoms and the Ocean Carbon Cycle Revisited

Terrestrial ecologists and biogeochemists are in direct contact with their objects of study via sense organs evolved in those environments; they hence share a common awareness because they can all see the whole elephant, as in the ancient Indian parable. Pelagic ecologists and biogeochemists on the other hand are the blind men groping different parts of the elephant - the protist-dominated biome of the planet - in attempts to understand its structure and functioning in terms of organism life cycles and the biogenic elements of which they are made. The pelagial is an alien world for us that we can only sense through instruments of our making: the propensity for bias is enormous. Throughout my career I have been acutely aware of this fundamental problem faced by protist ecologists. In this essay I would like to convey an impression of the subjective driving forces that led me to the conclusions I reached on the relationships between ocean ecology and biogeochemistry in the light of evolution by natural selection. Key personal encounters with sinking diatom blooms are recounted to illustrate how my convictions grew that led me to challenge mainstream thinking of the time.