2019.3.5 L261 Are All Our Organs Vital?


Medicine has not always shown a lot of respect for the human body. Just
think about the ghoulish disregard early surgeons had for our corporeal
integrity. They poked holes in the skull and copiously drained blood
with leeches or lancets—a practice that remained a medical mainstay
through the late 19th century. Even today many of the most popular
surgeries involve the wholesale removal of body parts—the appendix,
gallbladder, tonsils, uterus (usually after the childbearing years)—with
an assurance that patients will do just fine without them. There are
many valid reasons for these “ectomies,” but what has become
increasingly less defensible is the idea that losing these organs is of
little or no consequence.

A team of researchers in China recently found a new species of dinosaur,
and it might be the oldest link between dinosaurs and modern birds. The
paleontologists discovered the 125-million-year-old fossil in Lionaning,
China. The ancient animal was three-feet long, covered in feathers, and
sported a mouthful of teeth.


Take the appendix. Or rather leave it be, if possible. Many of us
learned in school that this tiny, fingerlike projection off the colon is
a useless, vestigial remnant of our evolution, much like the puny leg
bones found in some snakes. But that idea has been debunked, says
evolutionary biologist Heather Smith, director of Anatomical
Laboratories at Midwestern University in Arizona. A 2017 study led by
Smith reviewed data on 533 species of mammals and found that the
appendix appears across multiple, unrelated species. “This suggests
there’s some good reason to have it,” she says.

The new species has been named Jianianhualong tengi. Scientists
announced its discovery in a study published on May 2 in Nature


The reason appears to be immunological and gastrointestinal. In all
species that have an appendix, Smith notes, it either contains or is
closely associated with lymphoid tissue, which plays a role in
supporting the immune system. In humans, the appendix also harbors a
layer of helpful gut bacteria—a fact discovered by scientists at Duke
University. In a 2007 paper, they proposed that it serves as a “safe
house” to preserve these microbes, so that when the gut microbiome is
hit hard by illness, we can replenish it with good guys holed up in the
appendix. Some evidence for this idea surfaced in 2011, when a study
showed that people without an appendix are two and half times more
likely to suffer a recurrence of infection with Clostridium difficile, a
dangerous strain of gut bacteria that thrives in the absence of
friendlier types.

Jianianhualong tengi is a type of troodontid, which is a family of
bird-like dinosaurs related to the modern-day birds. Researchers are
unsure if Jianianhualong tengi could fly. But the well-preserved
fossilized remains indicate that it had feathers that were not
symmetrical, or longer on one side than the other. This is a key element
in the evolution of animal flight.


The appendix may have more far-flung roles in the body—including some
that can go awry. A study published last October found that misfolded
alpha-synuclein—an abnormal protein found in the brain of Parkinson’s
disease patients—can accumulate in the appendix. Intriguingly, the study
found that people who had the organ removed as young adults appear to
have some modest protection against Parkinson’s.

“Asymmetrical feathers have been associated with flight capability, but
are also found in species that do not fly, and their appearance was a
major event in feather evolution,” the authors write in the study.


New research has also shed light on the value of our tonsils and
adenoids. In a study published last July, an international team assessed
the long-term impact of removing these structures, or leaving them, in
1.2 million Danish children. Over a follow-up period of 10 to 30 years,
the 5 percent or so who had one or both sets of organs extracted before
age nine were found to have a twofold to threefold higher rate of upper
respiratory diseases and higher rates of allergies and asthma. Notably
they suffered more frequently from ear infections and, in the case of
adenotonsillectomies, sinus infections—conditions thought to be helped
by surgery.

Paleontologists first discovered that dinosaurs sported feathers with
the 1861 discovery of the Archaeopteryx, a different type of bird-like