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Course: American Museum of Natural History > Unit 3
Lesson 3: Evolution and human health and well-being (American Museum of Natural History)- How evolution saves lives and promotes prosperity
- Solving problems with phylogenetic trees
- Conservation genetics and conserving biodiversity
- Genes and health—moving beyond race
- Malaria—natural selection and new medicine
- Our balancing act with viruses
- What is a virus?
- Quiz: Evolution and human health
- Exploration Questions: Evolution and human health
- Answers to Exploration Questions: Evolution and human health
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What is a virus?
Viruses infect every living thing and may be as old as life itself. Everywhere there’s life on Earth, from high up in the atmosphere to deep in the ocean, there are viruses. The vast majority aren’t harmful to humans at all, but to understand the few that are—like the SARS CoV-2 virus behind the COVID-19 pandemic—we must learn about the connections between humans, viruses, other organisms, and the ecosystems we co-habit.
For thousands of years, humans didn’t even know that viruses existed. They were too small to be seen by early microscopes, and it wasn’t until the late 19th century that a scientist attached the word “virus” to a category of microbes that can cause disease. Today, we’ve learned that viruses are found in all groups of living things, from bacteria to plants and animals. Some pose no threat to our health, while others cause infections, including human diseases like smallpox and AIDS.
Created with the support of the City of New York Department of Health and Mental Hygiene.
© 2021 City of New York.
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SOURCES:
Andiman, Warren. Animal Viruses and Humans, a Narrow Divide: How Lethal Zoonotic Viruses Spill over and Threaten Us. Philadelphia, Paul Dry Books, 2018.
Chakraborty, Arup, and Andrey Shaw. Viruses, Pandemics, and Immunity. Cambridge, Massachusetts; London, England MIT Press, 2021.
Crawford, Dorothy H. The Invisible Enemy: A Natural History of Viruses. Oxford, Oxford University Press, 2002.
Desalle, Rob. Epidemic!: The World of Infectious Diseases. New York, The New Press, 1999.
Maxmen, Amy, and Smriti Mallapaty. “The COVID Lab-Leak Hypothesis: What Scientists Do and Don’t Know.” Nature, 8 June 2021, www.nature.com/articles/d41586-021-01529-3, 10.1038/d41586-021-01529-3. Accessed 2 Dec. 2021.
Quammen, David. Spillover. London, The Bodley Head Ltd, 2012.
Zimmer, Carl. Planet of Viruses. S.L., Univ of Chicago Press, 2021. Created by American Museum of Natural History.
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- Coronaviruses and rhinoviruses mutate so rapidly that we can't make a vaccine for the common cold. Many semi-literate people already knew that. Why was the COVID vaccine promoted as a way to prevent COVID?(1 vote)
Video transcript
>>NARRATOR: In the 17th century, a sickness was sweeping
through Amsterdam. People were driven to madness by... tulips. At one point of this tulip mania, it cost
less for a famous painter to paint you a still life of tulips than it did to buy a single
rare bulb. One of the most desirable of all was the ‘broken
tulip.’ Scientists later learned its special look
was caused by a virus, but no one knew that at the time. We didn’t even know that viruses existed! 200 years later another sickness swept through
the Netherlands. This time, though, it didn’t result in pretty
flowers, but in dying tobacco plants. Researchers discovered that this disease was
caused by something so small it couldn’t even be seen under a microscope. One researcher dubbed it a ‘virus.’ Today, we’re able to see viruses using electron
microscopes, and we’re learning more about how they operate. We know that viruses are basically just instructions
for making more viruses—pieces of genetic material wrapped inside shells and looking
to reproduce. But they don’t crawl or swim or replicate
at all on their own. [SNEEZE] They need to be spread to a host. Bacteria, tulips, turkeys, and humans—we’ve
all got them. Viruses infect every living thing and may
be as old as life itself. The vast majority aren’t harmful to humans
at all. Of the viruses that infect humans, some, like
herpes viruses, evolved along with us. Almost every human on the planet has them
and generally, they’re not deadly. Other kinds of viruses showed up as people
started domesticating animals and living together in large groups—things like measles and
smallpox. Lately, new kinds of viruses are appearing. These ‘emerging’ viruses often pop up
when humans or farm animals come in contact with wildlife. They’re not so much new as new to us. A virus that originally evolved to infect
bats might mutate and jump to a camel. As the virus reproduces inside the camel’s
cells, maybe this time it mutates into a form that can infect humans. That’s exactly what researchers think happened
with a coronavirus named MERS. MERS and infections like it are called zoonotic
diseases—they arise when viruses hitch a ride from animals to humans. Some 60 percent of all human infectious diseases
hop from or between other species before moving into us. SARS-CoV-2—the virus behind COVID-19 that
sparked a pandemic and global economic crisis—was first identified in 2019 and quickly recognized
as closely related to a virus found in horseshoe bats. When we clear forests, build massive industrial
farms, and fuel climate change, we create new pathways for viruses to reach us and beyond. By destroying natural environments, we disrupt
protections that evolved over millions of years, putting both the species that live
there and the species causing the destruction—us—at greater risk. Viruses, tulips, and humans are all interconnected
and to see us only as separate or opposing forces is to miss an opportunity for scientific
understanding and saving lives. Part of fighting disease in the future will
be protecting our planet’s ecosystems and studying both viruses and the incredibly diverse
organisms that host them.