Exceptional food that worth a special journey. And all other foods that can kill you.
Sunday
Food Documentaries- Did the Discovery of Cooking Make Us Human?
Watch this video and learn why it is better to cook some type of food than to eat it raw. Learn why cooking our food created 'big human brains'?
Toss a steak on the
grill and you may be reenacting an event that helped separate men from apes
thousands of years ago. Cooking is
something we all take for granted but a new theory suggests that if we had not
learned to cook food, not only would we still look like chimps but, like them,
we would also be compelled to spend most of the day chewing.
Did
Cooking Make Us Human?
We are the only
species on earth that cooks its food - and we are also the cleverest species on
the planet. The question is: do we cook because we're clever and imaginative,
or are we clever and imaginative because our ancestors discovered cooking?
Horizon examines the evidence that our ancestors' changing diet and their
mastery of fire prompted anatomical and neurological changes that resulted in
taking us out of the trees and into the kitchen.
Cooking, according to a new theory from a Harvard
anthropologist, was a key turning point
in human evolution, and without it, we would still spend significant chunks of
our day chewing heaps of raw foods, BBC News reported.
Humans would need to
eat more than 10 pounds of fruits and vegetables a day -- a task which would
require six hours of chewing, Harvard Professor Richard Wrangham told BBC News.
Cooking, he said, allowed humans to begin eating meat.
Without cooking, an
average person would have to eat around five kilos of raw food to get enough
calories to survive.
"I think cooking
is arguably the biggest increase in the quality of the diet in the whole of the
history of life," he said.
"Our ancestors
most probably dropped food in fire accidentally. They would have found it was
delicious and that set us off on a whole new direction," he told BBC News.
When Homo erectus,
the first truly "human" of our ancestors, evolved 1.8 million years
ago, they had bigger brains and teeth than older species, along with the
ability to walk upright and run.
Homo
erectus also had smaller
guts.
"Cooking made
our guts smaller," Wrangham told BBC News. "Once we cooked our food,
we didn't need big guts. They're costly in terms of energy. Individuals that
were born with small guts were able to save energy, have more babies and
survive better."
Cooking also allowed
humans to spend more energy on thinking than on digestion, Professor Peter
Wheeler from Liverpool John Moores University told BBC News.
It is already
accepted that the introduction of meat into our ancestors' diet caused their
brains to grow and their intelligence to increase.
Meat - a more concentrated form of energy -
not only meant bigger brains for our ancestors, but also an end to the need to
devote nearly all their time to foraging to maintain energy levels.
As a consequence,
more time was available for social structure to develop.
Cooking Improved
Human Diet
Harvard Professor
Richard Wrangham believes there is more to it than simply discovering meat.
He thinks that it is
not so much a change in the ingredients of our diet, but the way in which we
prepare them that has caused the radical evolution of our species.
"I think cooking
is arguably the biggest increase in the quality of the diet in the whole of the
history of life," he says.
"Our ancestors
most probably dropped food in fire accidently. They would have found it was
delicious and that set us off on a whole new direction."
To understand how and
when our bodies changed, we need to take a closer look at what our ancestors
ate by studying the fossil records.
Our earliest ancestor
was the ape-like Australopithecus.
Australopithecus had a large belly containing a big
large-intestine, essential to digest the robust plant matter, and had large,
flat teeth which it used for grinding and crushing tough vegetation.
None the less, it was
Australopithecus that moved out of
the trees and onto the African savannah, and started to eat the animals that
grazed there.
And it was this
change of habitat, lifestyle and diet that also prompted major changes in
anatomy.
Bigger Brain
The eating of meat
ties in with an evolutionary shift 2.3 million years ago resulting in a more
human-looking ancestor with sharper teeth and a 30% bigger brain, called Homo
habilis.
The most momentous
shift however, happened 1.8 million years ago when Homo erectus - our first
"truly human" ancestor arrived on the scene.
Homo
erectus had an even bigger
brain, smaller jaws and teeth.
Erectus also had a
similar body shape to us. Shorter arms and longer legs appeared, and gone was
the large vegetable-processing gut, meaning that Erectus could not only walk
upright, but could also run.
He was cleverer and
faster, and - according to Professor Wrangham - he had learned how to cook.
"Cooking made
our guts smaller," he says. "Once we cooked our food, we didn't need
big guts.
Professor Peter
Wheeler from Liverpool John Moores University and his colleague, Leslie Aiello,
think it was this change in our digestive system that specifically allowed our
brains to get larger.
Cooking Helps in Energy
Transfer
Cooking
food breaks down its cells, meaning that our stomachs need to do less work to
liberate the nutrients our bodies need.
This, says Wheeler,
"freed up energy which could then be used to power a larger brain. The
increase in brain-size mirrors the reduction in the size of the gut."
Significantly Wheeler
and Aiello found that the reduction in the size of our digestive system was
exactly the same amount that our brains grew by - 20%.
Professor Stephen
Secor at the University of Alabama found that not only does cooked food release
more energy, but the body uses less energy in digesting it.
He uses pythons as a
model for digestion as they stay still for up to six days while digesting a
meal. This makes them the perfect model as the only energy they expend is on
digestion.
His
research shows that pythons use 24% less energy digesting cooked meat, compared
with raw.
So being human might
all be down to energy.
Cooking
is essentially a form of pre-digestion, which has transferred energy use from
our guts to our brains.
According to
Professors Wheeler and Wrangham and their colleagues, it is no coincidence that
humans - the cleverest species on earth - are also the only species that cooks.
Want to learn more
about food and cooking? Read The
Science and the Lore of the Kitchen
Documentary Film
Summary: Did the Discovery of Cooking Make Us Human?
In Horizon:Did Cooking Make Us Human?, a clutch of determined scientists
set out to discover the extent to which diet played a role in the evolution of
the human brain, using a variety of mildly alarming gadgets. Professor Peter
Ungar has a contraption he calls the Bitemaster 2, a mechanical chewing machine
he has fitted out with genuine Australopithecine gnashers. For the first time
in three million years they were set to work on a carrot, with remarkable
success, considering. On raw meat they performed less ably, but teeth from a later
human ancestor – smaller, sharper, "crestier" – made short work of
it. You certainly wouldn't want to get your finger caught in there, as Prof
Ungar nearly does. "Wait!" he yells at his start-button-happy
colleague.
The Australopithecines didn't eat animals;
skulls with fang holes show that it was the other way round. At some point in
our evolutionary history it's clear that we developed a taste for animal flesh,
but it's not altogether obvious when, or why. Hunting is tricky, risky,
time-consuming and exhausting, and there is little evidence that Homo habilis, for example, was any good
at it. In search of answers, Professor Travis Pickering went to meet some
Namibian Bushmen to get a feel for the hunter-gatherer lifestyle. Although it's
not glamorous work – it takes the Bushmen four hours in 40-degree heat to dig a
porcupine out of its hole – they left one in no doubt as to its importance.
"I don't particularly like eating porcupine," said one of the
Bushmen, smiling shyly, "but meat is meat."
The programme's most interesting contention
was that cooking led directly to our bigger human brains. "Cooking is
huge," said Professor Richard Rangham. "I think it's the biggest
increase in the quality of diet in the whole of the history of life."
Again, no one is sure when our ancestors first became chefs – estimates range
from two million to 800,000 years ago – and the fossil record hasn't been much
help so far. They've found charred animal bones (evidence of hunting prey with
fire) and butchered animal bones (evidence of meat-eating) but no charred and
butchered bones – yet.
As a popular-science programme this erred
slightly on the side of repetition, and made one a little impatient. As a
cookery programme, it put you off your dinner. It's not very appetising to
watch a scientist chew up a raw potato and spit it into a digesting machine, or
to see a professor push a length of raw steak into a live snake. The
advantages of a cooked diet are, from an evolutionary point of view, legion:
you absorb more calories while expending less energy, and you can make do with
a smaller, less elaborate gut. Which is just as well, because I didn't
feel like eating much of anything afterward.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment