My other blog, Dr. Amedeo, is currently sporting a blurb
about Aboriginal Australian ancestry (Ancient Humans post). I
thought an excellent parallel this week would be for this blog, Amedeo, to
discuss the lost Australian expedition of 1860-1861 and how it relates to a
problem called beriberi.
Let’s
meet the stars of the show.
Robert O’Hara Burke
Born in Ireland, member
of Australian army, police inspector
William John Wills
Born in England, studied in
Melbourne with interest in astronomy, meteorology and chemistry
John King
Born
in Ireland, military experience in India, camels
Charles Gray
British
sailor
So what
did these guys do? In 1860, an
expedition set out whose purpose was “for transversing the unknown interior of
the Australian continent.” While the
coasts of Australia had been settled, the vast interior of the continent
remained both unexplored and widely unknown.
The hopes for the expedition were to study the plants and animals of
Australia as well as collect meteorological, geographical and astronomical
data. The leader would be one Robert O’Hara
Burke and he chose William John Wills as his deputy. They amply supplied themselves with both
useful and illogical items.
Interestingly, the party became convinced that camels were essential to
the journey since both deserts and the Australian bush were extremely hot (but had very
little else in common).
No one
had crossed Australia from the south to the north before so an added bonus of
their trip would be the notoriety of being first to do so. Unfortunately, competition for the title came
in the form of John McDouall Stuart.
Burke became increasingly concerned that Stuart would beat his expedition
(which was
large and moved quite slowly), so he split the party by leaving groups
behind in different places. Eventually,
the whittled entourage became Burke, Wills, Gray and King. These four men took rations and successfully
reached the north shore of Australia before Stuart.
This is
where things start to go downhill for our explorers. Monsoon season was upon them so traveling
home was slow and rations were being depleted.
Their (arguably) biggest mistake was turning to the land, which they knew
little about, to supplement their food supply.
Upon seeing signs of Aborigines eating mussels from a fresh water creek,
our explorers procured some and ate.
They also began making nardoo, which
is commonly made from a local fern by Aboriginal tribes.
Not
long after, Charles Gray died. He had
suffered on the journey home: he was unable to walk and spoke
incoherently. One night, he was found
eating directly from their extremely depleted flour rations. He had claimed he craved it and couldn’t help
himself. The others did not understand
how he could steal from them, especially since the others were also finding
their health to be failing. Their legs
felt paralyzed, they felt inexplicable exhaustion, pain and listlessness.
Their
exploration originally was large and those left behind knew Burke, Wills, Gray
and King would need supplies on their return, so rations had been stored in
known places. These stores helped the
men’s health greatly and their odd symptoms began to recede.
However,
the men still wanted to supplement their supplies with food from the land so
they went to back making nardoo. Burke and Wills would pound and clean the
plant while King was out trying to collect more. Hypothermia began to plague them in addition
to fatigue, weakness, low pulse rates, and their bodies began to waste
away. Wills and Burke died.
Miraculously,
King was discovered by local Aborigines who nursed him back to health on a diet
of nardoo, fish and local animals. He
was eventually rescued and returned to Melbourne, but his health was
permanently damaged.
What in
the world was wrong with these men?
They
suffered from beriberi, which is a
deficiency of thiamine (also called vitamin B1,
Figure 38.1). This
little molecule is essential to many cellular functions and must be obtained
through our diet. One of the first signs
a body is lacking thiamine is neurological defects, such as confusion and
irritability. This eventually progresses
to serious problems with the peripheral nervous system and cardiovascular
problems followed by death.
Unknowingly,
the men were ingesting large amounts of thiaminase
I, a protein whose job is to break down thiamine. The mussels they ate were Velesunio ambiguus, which contain
thiaminase I. From the journals left
behind, it is unclear whether the men cooked the mussels or ate them raw. Proper cooking would have destroyed the
protein and saved their health.
This is about to become a common
theme.
When nardoo
is prepared by the Aborigines, ferns are ground into a thin paste, kept
separate from other food, and diluted with water. The expedition men ground their plants then
boiled it in water. The fern is full of
thiaminase I (Figure 38.2). The Aboriginal preparation ensured that
thiaminase I was inactive. The explorers
way did not. The men continued to eat
the protein, which continued to break down any thiamine they were able to eat
and their health plummeted. Obviously
when they recovered rations left behind, their health improved, but only went
downhill again when they returned to nardoo.
The
most interesting part of all this was Gray’s eating of the flour. Flour is full of thiamine. Gray’s body clearly knew what it needed and
forced him to crave the one food it knew had it.
I had
never heard of this story before listening to a podcast from “Stuff You Missed
in History Class” from the website www.howstuffworks.com. You can find it on iTunes by searching the
podcast name and hunting through their archives of shows. I highly recommend these podcasts if you have
time in the car and get sick of music!
Nardoo – a food prepared
from the fern Marsilea Drummondii
Beriberi – a disease
caused by a body’s deficiency in the vitamin thiamine
Vitamin – any organic
molecule that is required by the body but the body cannot make itself (so it
must be found in the diet)
Thiaminase I – a protein
that breaks down thiamine
REFERENCES
Earl and McClearly. “Mystery of the poisoned expedition.”
Nature (1994) 368(6473) pgs 683 – 684.
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