JANUARY 2011: My Surface Interval named one of the best scuba diving blogs

Monday, June 7, 2010

The Deep at the Natural History Museum

The deep dark ocean. You could be forgiven for thinking the inky black depths are devoid of life. But a new exhibition at the Natural History Museum is offering a rare glimpse at the life that lives hundreds of metres below the waves.

This is an area rich in weird and wonderful alien looking creatures, marine life that has adapted to the seemingly inhospitable darkness and pressure to eek out an existence far from the gaze of man.

But using discoveries of the past and present, the Deep exhibition has revealed how some of the strange creatures live their lives. From the fish that use bioluminesence to disguise themselves or to hunt to those that dislocate their jaws to swallow prey greater than their own body weight.

These are also creatures with big teeth - you never know how long it might be until your next meal comes along so its best to keep hold of what you get. Having spent a couple of hours walking around the exhibition, I was over-awed.

The oceans cover seven-tenths of the Earth's surface with an average depth of almost 4km, but plummeting in places to 11km deep.

Amazingly, (as I discovered when given a Project Aware teaching presentation on my PADI instructor exam) the oceans provide about 190 times as much living space as all of the Earth's other environments - that's soil, air and fresh water put together.

Until the Challenger expedition of 1872, little was known about what lived in the depths of the ocean, beyond the twilight zone and into the perpetual darkness deeper than 1km. Over four years the expedition discovered much of what we now know to be true.

And with much of the ocean still to be explored (more men have stepped on the moon than have been to the deepest depths of the ocean) scientists are continually discovering new things - some of them very surprising.

The Deep exhibition reveals some rare specimens and models from shimmering jellyfish and scary angler fish to giant spider crabs and colossal squid. At the centre of the exhibition is a real sperm whale skeleton that has never been on display before.

The record for the deepest fish goes to Abyssobrotula galatheae, a member of Ophidiidae family. It was dredged from the bottom of the Puerto Rico Trench at a depth of 8,368m in 1970.

The largest known deep sea fish is the Greenland shark, Somniosus microcephalus, which grows to over 7m in length. However, it doesn't spend all its time in the deep sea. It also comes up to the surface to eat offal thrown overboard from fishing boats.

No comments: