Tag: dna

Fish Detectives

  • The fish detectives (a.k.a. scientists who specialize in fishery genetics) survey the scene. (Photo courtesy of the Lake Erie Center)

On television, the CSI detectives make forensic lab work look glamorous. It’s a cinch for them to track a criminal by the DNA left behind at the scene. In real life, DNA is also a powerful tool for solving environmental crimes and mysteries. Rebecca Williams visits the Fish Detectives:

Transcript

On television, the CSI detectives make forensic lab work look glamorous. It’s a cinch for them to track a criminal by the DNA left behind at the scene. In real life, DNA is also a powerful tool for solving environmental crimes and mysteries. Rebecca Williams visits the Fish Detectives:


(Sound of gulls and reel being cast)


It’s midday, and it’s so hot the gulls are just standing around with their beaks open.


But Joe Al-Sorghali is still trying to get himself a fish dinner:


“Hopefully I can get a good amount of perch today… they’re not that fishy so they’re a really good catch.”


It takes a lot of these little fish to fill up a dinner plate. But that doesn’t stop Al-Sorghali from going after perch and walleye any chance he gets. A lot of people call Lake Erie the Walleye Capital of the World.


Fishing is a really big deal here. So it makes sense that Lake Erie’s also home to the Fish Detectives.


(Dragnet theme music)


The fish detective headquarters is tucked away on the edge of a quiet cove. The investigators at the Lake Erie Center are not wearing trench coats. They’re not even wearing lab coats. This crew of laid-back lab techs and grad students comes to work in jeans and T-shirts.


Carol Stepien heads up the fish detective squad. She says they solve lots of cases of mistaken identity.


Take the Case of the Fried Perch.


Last year the detectives got a call from a TV station in Milwaukee. The news crew was suspicious that the fried local perch on restaurant menus wasn’t really local.


Stepien says she asked the news station to send her some frozen filets.


“So instead they sent their news crew out into restaurants and had their news crew eat the fish and put a little bit of the breaded, cooked fish in a plastic bag and froze those and sent them to me. We were pretty shocked to get those in our laboratory. We didn’t know if we could get DNA from breaded, fried material like that.”


But Stepien says they scraped off the breaded coating… and they actually were able to extract DNA from the little bits of cooked fish.


“And we found that about half of those fish were yellow perch from Europe.”


Stepien says it’s gotten more common for fish brokers to import yellow perch from outside the U.S. because it’s cheaper. She says even though the foreign perch might taste the same when they’re deep-fried… a close look at the DNA of the European yellow perch reveals big differences from Great Lakes yellow perch.


“They probably could be called freshly caught lake perch, but they were certainly frozen and didn’t come from any local lakes, they didn’t come from the Great Lakes. Instead they came from overseas.”


Stepien’s team will tackle any sort of mystery, as long as it involves gills and fins.


Lately they’ve solved cases of home invasion. That is, invasions by exotic species that’ve gotten into the Great Lakes. The scientists can track the invaders by their DNA fingerprints, and find out where they’ve been.


Joshua Brown is a Ph.D student at the lab. He’s been tracking the round goby. It’s a fish native to Europe. Scientists say it caught a ride to the Great Lakes in the ballast tanks of ocean going ships. It’s been crowding out native species.


“We’re going to find somebody to point the finger at, as it were. We’ve found evidence they came from the northern portion of the Black Sea, right around one of the major ports.”


That port is in Ukraine. Even though they’ve found the culprit, Brown says there’s not much governments can do, because everyone’s guilty.


“I don’t think you could really sue a nation for you know, not keeping their species under wraps. If so, we’d be open for a lot of lawsuits too – we export almost as many as we import.”


But Brown says knowing exactly where a foreign species comes from might help keep the door closed to future invaders from that same region.


Whether it’s a case of consumer fish fraud or defending the home turf from invaders, there’s one bottom line for these detectives. They want to find out as much as they can about native fish so they can keep them from going belly up.


For The Environment Report, I’m Rebecca Williams.

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Seed Bank Hopes to Save Trees in Peril

  • Examples of ash tree seeds that are part of the collection effort. (Photo by Lester Graham)

People have been saving seeds for thousands of years. Gardeners save
seeds of their favorite plants. Governments save seeds to protect
their food crops. Now, some people are freezing the seeds from trees.
That’s because the trees are being destroyed by an insect pest.
Rebecca Williams reports they’re hoping a gene bank will protect the
trees’ DNA and some day help bring the trees back:

Transcript

People have been saving seeds for thousands of years. Gardeners save
seeds of their favorite plants. Governments save seeds to protect
their food crops. Now, some people are freezing the seeds from trees.
That’s because the trees are being destroyed by an insect pest.
Rebecca Williams reports they’re hoping a gene bank will protect the
trees’ DNA and some day help bring the trees back:


Seeds are a pretty amazing little package. They might be small, but
they’re tough. They can live through very dry and very cold
conditions.


(Sound of seed being shaken out of a paper bag)


These seeds are from ash trees. In some parts of the Upper Midwest and
Ontario, ash trees have been wiped out. The seeds are all that’s left.
That’s because of the emerald ash borer. It’s a tiny green beetle that
got into the US in cargo shipped from China. So far, the beetles have
killed 20 million ash trees. No one’s been able to stop the beetles
from spreading.


David Burgdorf works for a lab with the US Department of Agriculture.
He says people might not even know they had ash trees until the trees
got attacked:


“If your lawn was filled with the ash tree and you had all this great
shade and your energy bills were low, but now the ash tree’s gone, you
only miss it when it’s gone.”


Burgdorf says a lot of people love ash trees for their gold and purple
fall colors. They grow fast and hold up well under ice storms. Native
American tribes depend on black ash for making baskets and medicine.


David Burgdorf is trying to make sure ash trees won’t disappear completely
if the beetle spreads across the country. He’s gathering ash seeds
sent in by volunteers. He’s hoping to build a collection that
represents the entire ash tree gene pool:


“We want to try not to have to bring something back. We don’t want it
to be extinct. It’s important we at least save the seed so we can maybe cross
it, or do something, breed in resistance to the tree and have it
available to come back.”


Burgdorf says he thinks of the seeds as an investment for the future.
The seeds are definitely being treated like a precious commodity.
They’re sorted and they’re X-rayed to make sure the living embryos in
the seeds haven’t been damaged.


Then, the very best seeds in the bunch are off to a high security
government vault:


“We kind of joke that it’s the Fort Knox for seeds.”


Dave Ellis is the seed curator at the National Center for Genetic
Resources Preservation. It’s a giant seed bank. Ellis says the ash
seeds are dehydrated and frozen at 0 degrees Fahrenheit. These steps
put the seeds into a deep sleep:


“In a dehydrated state, degradation of DNA happens much more slowly,
over a course of tens of years or hundreds of years.”


Ellis says the ash seeds should be viable for at least 25 years, if not
longer. He says researchers might be able to use the stored genetic
material to breed new pest-resistant ash trees in the future. Ellis
sees gene banks as a safeguard against a world that’s changing fast.


Scientists say wild plants and crops we depend on will face many new
threats. Climate change might bring more drought.
Escalating global trade could mean importing more pests.


Deb McCullough studies insect pests at Michigan State University. She
says any time you import cargo, you’re running the risk of also
importing pests that can run up huge bills. She says in North America,
one of the big concerns is imports from China:


“If you look at the latitude where China occurs, if you look at the
northern and southern latitude and you overlay that on top of the US and
Canada, it matches up almost perfectly. So you can figure that pretty
much any kind of climate or habitat you find in China, there’s going to
be something similar in the US.”


McCullough says not everything that gets in will turn out to be a pest,
but she says as China’s huge trade surplus with the US grows, there’s a
greater risk more pests will come in.


She says there are some new regulations in place, but restricting
international shipping is a tricky proposition. McCullough says seed
collecting might be one way to preserve plants we rely on:


“People who are molecular biologists, the gene jockeys, have gotten
very good at enhancing or producing resistant varieties of different
kinds of plants. So, that may be something that becomes an option in the
future, maybe not the too distant future.”


McCullough points out there will be serious debate about introducing a
genetically modified tree into the wild. Some people don’t like the
idea of manipulating the genetic makeup of plants or animals.


There are a lot of questions about what might be done with the frozen
seeds, but the seed collectors say regardless, they need to bank up the
DNA of plants that we’re in danger of losing.


For the Environment Report, I’m Rebecca Williams.

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New Tools to Detect Bioterrorism

A new study finds that the air you breathe could be teeming with more than
1,800 types of bacteria. Rebecca Williams reports the research might help
protect against bioterrorist attacks:

Transcript

A new study finds that the air you breathe could be teeming with
more than 1,800 types of bacteria. Rebecca Williams reports the
research might help protect against bioterrorist attacks:


This is the first time researchers have used DNA sequencing to study
bacteria in the air. They wanted to find out what’s normal and what’s
harmful.


Federal officials are hoping to improve on the way they test the air for
potential bioterrorism agents.


Gary Andersen is the lead author of the study… published in the
Proceedings of the National Academy of Sciences. He says the
current monitoring system tests the air above most major U.S. cities
for specific pathogens. He says the new research will make that
system better.


“To see not just whether or not these specific handful of pathogens
were present but what actually was the microbial composition in the
air and that also may give some clue to as whether things are normal
or suspicious circumstances.”


Andersen says the research will make it clearer whether or not people
are actually in danger.


For the Environment Report, I’m Rebecca Williams.

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Legislation Dividing Organic, Biotech Farmers

  • Organic farms are concerned about nearby farms that produce genetically modified crops. They fear that the genetically modified crops will cross with and alter the genes of their own crops. (Photo by Rene Cerney)

The nation’s agricultural seed companies are fighting local restrictions on their genetically engineered products. They say it’s the federal government’s job to regulate food safety. But critics say federal agencies aren’t doing a good job of testing genetically modified food for safety. They’re backing the right of local governments to regulate genetically engineered crops themselves. The Great Lakes Radio Consortium’s Sarah Hulett reports:

Transcript

The nation’s agricultural seed companies are fighting local restrictions on
their genetically engineered products. They say it’s the federal
government’s job to regulate food safety, but critics say federal agencies
aren’t doing a good job of testing genetically modified food for safety.
They’re backing the right of local governments to regulate genetically
engineered crops themselves. The Great Lakes Radio Consortium’s
Sarah Hulett reports:


Genetically engineered crops are created when genes from other plants,
animals or bacteria are used to alter their DNA.


Critics call them “Franken-foods,” and two years ago, three California
counties banned farmers from growing genetically altered crops. That
alarmed the agribusiness industry, and now it’s fighting to keep that from
happening elsewhere.


So far, the industry successfully lobbied 14 states to pass laws preventing
their local governments from putting restrictions on engineered crops.
Four other states are considering similar measures.


Jim Byrum is with the Michigan Agri-Business Association.


“Frankly, it’s pretty frustrating for us to look at some of the rumors that
are floating around about what happens with new technology. It’s
reduced pesticide use; it’s reduced producer expense in production. It’s
done all sorts of things.”


Genetically engineered seeds are created in the laboratories of big seed
companies like Monsanto and DuPont. The modified plants can produce
higher-yield crops that make their own insecticides, or tolerate crop-
killing problems such as drought or viruses.


Proponents of the technology say genetically altered crops have the
potential to feed the world more efficiently, and they say it’s better for
the environment. That’s because the crops can be grown with fewer
polluting pesticides, but critics say not enough is known yet about
engineered crops’ long-term ecological impact, or on the health of
people who eat them.


(Sound of farm)


Michelle Lutz is among the skeptics. She and her husband run an 80-
acre organic farm north of Detroit. She’s watching about a dozen head of
the beef cattle she’s raising. They’re feeding on cobs of organic corn
grown several yards away.


“I’m surrounded by conventional farmers. The farmers right over here to
my east – they’re good people, and I don’t think they would intentionally
do anything to jeopardize me, but they are growing genetically modified
corn.”


Lutz worries that pollen from genetically modified corn from those
nearby fields could make its way to her corn plants – and contaminate
her crop by cross-breeding with it. Lutz says people buy produce from
her farm because they trust that it’s free from pesticides, because it’s
locally grown, and because it has not been genetically altered. She says
she shares her customers’ concerns about the safety of engineered foods.


Lutz says letting local governments create zones that don’t allow
genetically engineered crops would protect organic crops from
contamination.


But Jim Byrum of the Michigan Agri-Business Association says no
township or county should be allowed to stop farmers from growing
genetically modified crops. He says every engineered seed variety that’s
on the market is extensively tested by federal agencies.


“Frankly, that evaluation system exists at the federal level. There’s
nothing like that at the state level, and there’s certainly nothing like that
at the local level. We want to have decisions on new technology, new
seed, based on science as opposed to emotion.”


Critics say the federal government’s evaluation of genetically modified
crops is not much more than a rubber stamp. The FDA does not approve
the safety of these crops. That’s just wrong.


Doug Gurian-Sherman is a former advisor on food biotechnology for the
Food and Drug Administration.


“It’s a very cursory process. At the end of it, FDA says we recognize that
you, the company, has assured us that this crop is safe, and remind you
that it’s your responsibility to make sure that’s the case, and the data is
massaged – highly massaged – by the company. They decide what tests
to do, they decide how to do the tests. It’s not a rigorous process.”


Gurian-Sherman says local governments obviously don’t have the
resources to do their own safety testing of engineered foods, but he says
state lawmakers should not allow the future of food to be dictated by
powerful seed companies. He says local governments should be able to
protect their growers and food buyers from the inadequacies of federal
oversight.


For the GLRC, I’m Sarah Hulett.

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Mapping Wooly Mammoth Genome

Wooly mammoths stopped roaming the Great Lakes region 10,000 years ago. But a Canadian scientist has made a breakthrough in reviving their prehistoric genetic code. The Great Lakes Radio Consortium’s David Sommerstein reports:

Transcript

Wooly mammoths stopped roaming the Great Lakes region 10,000 years
ago, but a Canadian scientist has made a breakthrough in reviving their
prehistoric genetic code. The Great Lakes Radio Consortium’s David
Sommerstein reports:


Scientists have studied ancient DNA in the past, but only in fragments.
Geneticist Hendrik Poinar got well-preserved DNA from a wooly
mammoth found in the Siberian permafrost. Poinar is an assistant
professor at McMaster University in Hamilton, Ontario. He and
colleagues at Penn State University have found a way to map the entire
mammoth genome.


“So, it’s really having a Kodak moment on the genes of the past, really,
as they were evolving, and being able to answer fascinating questions
about what makes a mammoth a mammoth, or what makes a Neanderthal a
Neanderthal, and how they differ from a human.”


So far, they’ve completed just one percent of the genome.


Poinar says the discovery begs tough ethical questions, like bringing
extinct animals back to life.


“Creating Pleistocene Park, basically.”


Poinar published the discovery in a recent issue of the Journal Science.


For the GLRC, I’m David Sommerstein.

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Home Renovation Turns Up Surprise for Science

  • Egg collectors kept precise records about where and when their prize possessions were gathered. They carefully removed the contents of the egg, then nested the shells in cedar sawdust to protect them from insects. (Photo courtesy of Carrol Henderson)

More and more people say their favorite hobby is bird-watching. Many travel to hot bird-watching spots, and keep lists of which birds they see and where. A hundred years ago, birders were just as enthusiastic, but they practiced the hobby very differently. They collected bird eggs. A Midwestern farm family recently discovered an ancestor’s egg collection when they were remodeling an old farmhouse. Experts say the collection has a lot to offer to scientists studying birds today. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:

Transcript

More and more people say their favorite hobby is
bird-watching. Many travel to hot bird-watching spots, and keep
lists of which birds they see and where. A hundred years ago,
birders were just as enthusiastic, but they practiced the hobby
very differently. They collected bird eggs.


A Midwestern farm family recently discovered an ancestor’s egg collection when they were
remodeling an old farmhouse. Experts say the collection has a
lot to offer to scientists studying birds today. The Great Lakes
Radio Consortium’s Stephanie Hemphill reports:


Carrol Henderson considers himself a very lucky man. He’s the director of the non-game wildlife program at the Minnesota Department of Natural Resources. He grew up on a farm in central Iowa.


Last summer, he learned that a family in his old neighborhood was renovating a farmhouse. It had belonged to Ralph Handsaker. When Handsaker died thirty years ago, the house was boarded up and left alone.


“… And when the family started renovating this old farmhouse for the great-great-grandson, John Handsaker, along with a number of old animal mounts and interesting things, there were these two large chests with about fifteen drawers each, that were totally filled with little sets of wild bird eggs.”


The smallest egg, from a hummingbird, was small enough to sit on top of a dime. The biggest was an ostrich egg almost six inches long. Some were creamy white, others were speckled, others streaked with color like a Jackson Pollack painting.


There were more than 3,600 eggs, representing more than 400 species of birds from all over the world. And they were in perfect condition.


“Each set of eggs was very neatly labeled with information about the day they were collected, who the collector was, and information about the habitat where the egg was collected. Some of these eggs went all the way back to 1875, and they were collected by over three hundred different people from all over the world.”


This is how nature-lovers expressed their passion in those days. They called themselves oologists. They kept their eggs in drawers lined with cedar sawdust to protect them from insects. They also kept meticulous records.


“So the scientific data was very high quality among these avid collectors. So even today, these provide very important nest records for birds that are now gone. Like in my home county of Story County, Iowa, there were Marble Godwits, King Rails, Prairie Chickens, and Bobwhite Quail, and those are all gone now.”


The birds disappeared as people turned prairies into farms. But Carrol Henderson says the records in the bird collection provide detailed information about where and when they nested.


“And another intriguing thing is that when these people blew out the eggs, there was still a lining of the egg white or albumen left inside the egg. And that still has the original DNA genetic material, so it actually would be possible for scientists to do DNA analysis of these eggs to take a look at how they may compare with birds nowadays.”


Henderson says these collectors didn’t think they were harming the birds. That’s because if their eggs disappear, most birds will lay another set. But competition for the eggs of rare birds was disastrous.


“One person in Philadelphia had a collection of over seven hundred Peregrine Falcon eggs. Another Peregrine egg collector went to the same cliff and collected all the eggs from the Peregrines every year for 29 consecutive years. And then finally the nest was abandoned. And he said it was abandoned due to encroaching civilization. That was where egg collecting really had something of a dark side.”


Eventually, attitudes began to change. In 1918, the federal government passed the Migratory Bird Treaty Act, to protect birds and eggs. But the government let three collectors keep on collecting. One of them was Ralph Handsaker. So his collection goes into the early 1950’s.


Carrol Henderson says there’s a lot to learn from these eggs. One of the best lessons is about human responsibility. Henderson says people these days enjoy nature differently than they did a hundred years ago. But we can still learn something from earlier methods.


“It’s like a little time machine: stepping back in time, seeing what was here, and then looking at what’s changed, and what does that mean for our own conservation efforts, how can we do a better job today to collect information and use that for our own conservation of wildlife species?”


Carrol Henderson’s article about the Handsaker egg collection will appear in the October issue of Birders World magazine. The Handsaker family is planning to donate the collection to a major university.


For the GLRC, I’m Stephanie Hemphill.

Lynx Found in Northwoods

The Canada lynx used to live in forests from New York to Minnesota, but some people doubted that the northern relative of the bobcat still lived in the Great Lakes region. Now, biologists have confirmed that lynx are in northern Minnesota. The Great Lakes Radio Consortium’s Chris Julin reports:

Transcript

The Canada lynx used to live in forests from New York to Minnesota, but some people doubted that the northern relative of the bobcat still lived in the Great Lakes region. Now, biologists have confirmed that lynx are in northern Minnesota. The Great Lakes Radio Consortium’s Chris Julin reports:

Biologists have been trying to snag hair from lynx for the past couple years. None of the “hair traps” around the Great Lakes turned up any lynx fur. So researchers in the Superior National Forest tried following tracks where people said they had seen lynx. They collected samples of hair and droppings. Superior National Forest spokeswoman Jo Barnier says DNA tests confirm that some of the droppings came from lynx.

“We’re not sure exactly what it means beyond that fact that we know they’re here this year. What we don’t know is whether we have lynx here year after year, and how many individual lynx we may have.”

The evidence of the lynx won’t mean any changes in logging or recreation. Forest managers in much of the lynx’ former range already follow rules assuming the presence of lynx.

In Duluth, this is Chris Julin for the Great Lakes Radio Consortium.

Cougars Still Stalking the Region?

For many years, state and federal wildlife officials have considered the cougar extinct in the Great Lakes region. However, many people claim to have seen the large predatory cat long after it supposedly disappeared. Conservationists debate whether these sightings are real and if they are, they wonder whether the cougars are wild or merely escaped pets. Investigations are underway in many states, including Minnesota, Wisconsin and Pennsylvania, and in Canada. Now, a wildlife biologist in Michigan says he has proof that a breeding population of wild cougars is living in the Upper Peninsula. The Great Lakes Radio Consortium’s Gretchen Millich reports:

A Revolution Among Plant Scientists

Scientists are discovering new genetic information about plants is
upsetting the natural order of things. The Great Lakes Radio
Consortium’s Lester Graham reports that they’re also finding a whole new
world of possibilities for using plants for medicines and products: