Page 57 - BBC Focus - August 2017
P. 57
SPINY CRAB FOR THE FIRST TIME,
With its spectacularly SC SCIENTISTS HAVE
S S
spiky body armour, this
ORED THE DEEP
crab was immensely well EXPLO SEA
S
protected as it stalked O OFF AUSTRALIA,
around on the seabed. REVEALING O NEW
G A WHOLE
Even its colour is
’
D
protective, helping it WORLD THAT’S FILLED
hide in the dark depths WITH BIZARRE C TURES
CREAT
because seawater
absorbs red light. “You
lose it [red light] pretty WORDS: DDR HELEN SCALES S
ATT/CSIRO
quickly as you go down, PHOTOS :: ROB ZUGARO/ASHER FLA
so everything becomes
blue,” says Bray. This aceless fish, zombie
means that red pigments worms and herds of
appear black, which F sea pigs were among
would have made the the wonders hauled up
crab incredibly difficult from the ocean depths
to spot. Most deep-sea by a research team
animals haven’t evolved working off Australia’s east coast.
red vision – an added Scientists from seven countries spent a
bonus for this month on the research vessel RV
crustacean. Investigator, starting in Tasmania and
working their way north as far as the
Coral Sea. While the shallower waters in
this region are well known, this was the
first expedition to focus on the
unexplored depths.
Along the way, the team, led by Dr Tim
O’Hara from Museums Victoria, mapped
the seabed in detail for the first time with
underwater cameras and sonar. They
discovered rock-covered plains, colossal
canyons and mountains. Every 1.5° of
latitude they sent a trawl net to the
seabed. It took up to six hours for the net
to go down to 4,000m (2.5 miles) and
come back up. “It makes you appreciate
what you get,” says Dianne Bray, a fish
specialist from Museums Victoria who
was on the ship. “These things are so
valuable and precious.”
A metal sled was dragged along the
bottom to gather mud-dwelling creatures
and sample the seabed for signs of
pollution. As well as cans and bottles, it
brought up piles of clinker – residue from
coal-powered steamships that used to ply
these waters in the 1800s and early 1900s.
Of thousands of animals collected,
perhaps a third are new to science,
although it will take months of hard
work to tease out the details. The
preserved specimens will be used for
generations, to understand how Earth’s
biodiversity is changing. “They’re for the
people who aren’t yet born who will ask
questions that we can’t even envisage,
using methods that we can’t imagine,”
says Bray.
57
