Moving the Waters - Ocean Worlds: The Story of Seas on Earth and Other Planets - page 106

deep waters below the thermocline. Here, therefore, there are thin
pickings for every kind of planktonic organism, from viruses to whales.
Gyres are shunned by the kind of plankton that need a good nutrient
source, such as diatoms and radiolaria, and inhabited by those that can
make do with less, such as foraminifers and coccolithophores. It is the
skeletons of these hardier organisms that go on to make up the oozes
that accumulate far down on the deep ocean floor. These gyres are the
oceanic deserts of the world, and they are enormous.
The oceanic oases where marine life blooms, by contrast, are much
smaller. To find these, one needs to find a very specific kind of
current—one that comes from the deep.
We met Alexander von Humboldt in Chapter 3, being perplexed by
the oceans. Nevertheless, he was the man Darwin regarded as the
greatest scientific traveller who ever lived, and Thomas Jefferson
thought him the most important scientist he had ever met (although
Napoleon Bonaparte reputedly told Humboldt, 'You are studying
Botanics? Just like my wife!'). Humboldt's reputation survived
Napoleon's commentary, and his name now adorns a whole array of
earthly and unearthly objects. There is Pico Humboldt in Venezuela,
almost 4.5 kilometres high, and, in the same country, plumbing the
depths, the Sima Humboldt, a sinkhole. Nevada goes three better to
name after him a river, a lake (now dry), not one but two mountain
ranges (eastern and western), and a whole county. There is a Mare
Humboldtianum on the Moon, and even farther there is 54 Alexan-
dra, the first asteroid to be named after a man, orbiting the Sun. The
biological tributes range from Humboldt's lily, Lilium humboldtii , to
Conepatus humboldtii , Humboldt's hog-nosed skunk. And there are
many more monuments to him. Of all of these, though, one stands
out. Pride of place must go to the Humboldt Current, which flows
southwards past South America. It is the most productive part of the
world ocean.