Researchers
in fields from epidemiology to genetics are studying mummies, using the
latest imaging technology. Now we know more than ever before about what
lies beneath the mummies’ wrappings — and these long-dead people are
telling us a lot about ancient lives and cultures.
Just like
modern hospital patients, mummies are subjected to high-tech tests and
scans. X-ray, magnetic resonance imaging (MRI), and computed tomography
(CT) scans let researchers study the anatomy of mummies in 3D detail
without having to damage the remains with a physical autopsy. This keeps
the bodies intact, which is good for science — and can be more
respectful of ancient cultural traditions, too. Terahertz imaging,
the same technique used at airport security checkpoints, is useful for
looking at hidden objects like amulets tucked into a mummy’s burial
garments. Researchers can even take biopsies, or small samples of
tissues, to get a closer look inside a mummy’s organs.
CT scan of the mummy in the top image. Credit: U.S. Naval Hospital, San Diego.
What Pollen Can Reveal
Studying mummies can yield surprisingly personal glimpses into how people lived and died in the past. For instance, archaeologists used CT scanning and microscopic analysis of pollen to examine the mummified remains of an elderly Korean general who died in the 16th or 17th century.
In the CT
images, they found coprolites—preserved feces—in the general’s large
intestine. (There is little dignity in death, especially if your corpse
is historically significant.) Researchers were interested in the
coprolites because they wanted to know what the general had eaten in his
final days. In particular, they were interested in what kinds of pollen
the coprolites contained.
Depending
on how food is prepared, traces of pollen may get ingested along with
fruits, vegetables, spices, or teas. Pollen can linger in the digestive
tract for up to three weeks—and if you die and then get mummified, that
three weeks can stretch into thousands of years. In forensic terms,
pollen is the epitome of trace evidence. Pollen grains are tiny and easy
to overlook, but they can reveal a lot of information about what the
deceased ate and drank, what medicines (or recreational drugs) he took,
and even when he died.
So
researchers used chemical techniques to extract pollen from the
general’s last bowel movement and then examined the grains under a
microscope. His coprolites contained lots of pollen from aquatic plants,
but not as much as they would expect to find if he had just been eating
the plants; instead, the pollen seemed to have been in the
water. That says something about the general’s water sources, but it
also means that he probably drank a lot of tea and broth in the days
before his death. Analysis also uncovered pollen from a species of sage
often used as a medicine for abdominal pain, so it’s easy to imagine
that the general wasn’t feeling well—although his death appears to have
been due to injury, not illness.
However, it
seems that the general wasn’t entirely on a liquid diet in his last
days. Remains of buckwheat pollen, along with pollen from the mustard
family—which includes bok choy, broccoli, cabbage, cauliflower, cress,
and mustard—give us a picture of what he typically ate. And based on the
seasonal availability of those plants (because there wasn’t much of an
off-season market in the 1600s) it seems that the general died during
the winter, between November and February.
Tracing Modern Maladies
Mummification
doesn’t just preserve tissue. It can also preserve ancient DNA, and
scientists have the tools to extract it, sequence it, and study it. In
fact, some remains are so well preserved that scientists can extract the DNA of ancient bacteria, viruses, and parasites to learn about diseases in the past.
It’s a
challenging process, and researchers have to be careful not to
contaminate the remains with modern germs during excavation and lab
work. Over the last two decades, however, they’ve been pretty
successful. Diseases that have been buried with mummies around the world
include Spanish flu, leprosy, Hepatatis B, and the protozoa that causes
malaria.
Some of the first researchers to sequence DNA from an ancient pathogen were the scientists who extracted Mycobacteria tuberculosis bacteria DNA from a 1,000-year-old Peruvian mummy. They shared their results in a 1994 paper. Other researchers studied the DNA of tuberculosis in scores of Egyptian mummies, and they’ve tracked changes in the disease’s genome
over the 3,000 years of ancient Egypt’s history. Their work gave us a
better idea of where tuberculosis came from—and how it changes over
time.
Knowing the
evolutionary history of a disease helps modern epidemiologists predict
how the disease might evolve during modern outbreaks. It can also reveal
how the disease is related to other pathogens, pointing doctors toward
potential treatments or vaccines.
Mycobacteria tuberculusis. Credit: National Institutes of Health
It also
helps to know how common a disease was in an ancient population, how
quickly it spread, and which groups of people were most vulnerable.
Today, modern antimicrobial medicines can cover up other factors—like
environment or diet—that could make people more or less susceptible to a
pathogen. Learning how that pathogen behaved in a world before
antimicrobials can help doctors better understand how it spreads and how
to control it.
We’ve used
today’s most sophisticated imaging and DNA sequencing technologies to to
learn about the more humble parts of our ancestors’ lives. Archaeology
revealed their monumental architecture and offerings to the gods. But
only modern technology allowed us to learn what they ate and what ailed
them.
http:http://gizmodo.com/everything-weve-learned-about-mummies-using-21st-centur-1707512326//gizmodo.com/everything-weve-learned-about-mummies-using-21st-centur-1707512326
Everything We've Learned About Mummies Using 21st Century Technology
What Pollen Can Reveal
Tracing Modern Maladies