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Passenger pigeons died out in 1914; scientists
hope to bring them back
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By Scientific American, adapted by Newsela staff
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This photo shows
Martha (right), an extinct
passenger pigeon, at the
Smithsonian's Natural
History Museum in
Washington, D.C. Once
the most plentiful bird on
the planet, the passenger
pigeon became extinct in
September 1914 when
Martha died at the
Cincinnati Zoo. Photo:
AP Photo/Susan Walsh
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There were once more than 3 billion passenger pigeons in the world, but in 1914, there was just
one. Her name was Martha, and she lived alone in a cage in the Cincinnati Zoo.
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Her mate George had died four years before. Martha was the last, lonely bird of a species that
liked to be social.
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When Martha died, it was the end of a species. Passenger pigeons had gone extinct. Martha's
stuffed body is now on display at the famous Smithsonian Natural History Museum. Perhaps it's
not all over, though: What if the passenger pigeon could be brought back?
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DNA From A Stuffed Bird
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After all, long-dead animals still contain DNA, which is a set of instructions on how to form a
particular type of animal. DNA forms into packets called genes.
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Each gene is matched with a certain trait, or feature — everything from red hair in people to
powerful wings in birds. If enough genes can be recovered and recreated, maybe a long-gone
species could be brought back to life. That's the idea behind something called de-extinction.
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It works like this: Take DNA collected from extinct animals, like Martha. Figure out which
genes matter and combine them with the genes of a closely related species that still exists. Then,
take the combined genes and place them in the egg of one those still-living relatives. If all goes
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well, a copy of the long-lost Martha could hatch, and, one day, flocks of passenger pigeons could
be flying the skies.
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Pioneer Of De-Extinction
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Ben Novak is hoping to become a pioneer of de-extinction by bringing back the passenger
pigeon. Novak is collecting DNA from stuffed passenger pigeons and studying the genes of the
closely related band-tailed pigeon.
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So far, 32 passenger pigeon samples have had their genomes sequenced. "Genome" is simply the
word for the complete set of genes found in an individual animal. "Sequencing" means figuring
out the order, or sequence, of the genome's parts.
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The samples Novak is studying will also help him begin to figure out something else: how the
bird lived in the wild. Understanding that will help him decide if a restored passenger pigeon
would do well in today's woods. What Novak has learned so far is encouraging: nothing is telling
him to "turn back now and not bring back the passenger pigeon."
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Teaching New Birds Old Tricks
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If the de-extinction works, one remaining challenge would be to teach the new birds how to be
passenger pigeons. Doing that could be even more challenging than the genetic work itself. The
new birds would be part band-tailed pigeon, and would have no passenger pigeon parents to
teach them what to do.
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To understand the difficulty, look at similar efforts — raising California condors with puppets, or
teaching cranes to migrate by using ultralight airplanes. Still, if everything goes well, Martha
may no longer be the last of her kind. Birds that carry the genes of the passenger pigeon could be
flapping around by 2020. The project may be too difficult, however. Scientists have been trying
for 30 years to bring back the quagga — an extinct species of zebra, but have not been
successful.
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Researchers were able to bring back a bucardo — a goat species that was extinct — but the baby
goat only lived for seven minutes. They were not able to repeat the experiment. Nevertheless,
some are now considering other uses for the science used in de-extinction, saying the same
methods could be used to preserve animals and plants currently in danger of dying out.
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There are advantages, however, to working with an animal that is already extinct. For one thing,
you're not racing the clock, desperately trying to stop a species from disappearing. After all,
Martha died 100 years ago, so her kind has long been gone.
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If they succeed, the world gets a new kind of bird, Novak says. "If we fail, we learn things that
are valuable and the world isn't left with another extinct species."
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Name ____________________________________ Date ____________________Period ______
Directions: Write complete sentences to answer the following questions. Refer to the numbered
lines to show where you found the answers in this text.
1. Based on the title, what are the scientists trying to accomplish?
2. Referring to lines 27-34, describe the process of how the scientists use DNA to achieve
the goal.
3. Using evidence from the article describe how scientists have tried this process in other
animals. How successful have these attempts been?