Mice Morphing at Warp Speed

  • Oliver Pergams used a tiny caliper to measure the mice, tracking changes in size over the years. (Photo by Gabriel Spitzer)

Evolution takes place over long stretches of time: millennia and epochs. But some new research shows that animals might be changing much
faster than nearly anyone thought. Gabriel Spitzer has more on those
changes, and how they seem to be linked to humans:

Transcript

Evolution takes place over long stretches of time: millennia and epochs. But some new research shows that animals might be changing much
faster than nearly anyone thought. Gabriel Spitzer has more on those
changes, and how they seem to be linked to humans:

Tall Trees Park is a little patch of green in Glenview, Illinois – a
northern suburb of Chicago. About a hundred years ago, a lot of this area
looked a lot like this. It was mostly farms and pasture and forest. And now
of course it’s a lot of strip malls and subdivisions and stuff. And the
population has grown seventyfold. The climate has changed, too. It’s
gotten a little warmer, a little wetter.

And all this has made life a lot different for the northern white-footed
mice who live here. It’s actually not just made life different for the
mice, it’s changed the mice themselves.

That gets back to a guy named Oliver Pergams. He’s an ecologist, and in
the mid-90s, he was looking at deer mice who live on the Channel Islands
off the coast of California. And he was taking these mice and comparing
them to museum samples of the same kind of mice from the same place, but
decades earlier.

“And I found something kind of strange – that the older specimens were
larger than the newer specimens, so they shrunk in size over a period of
about 30 or 40 years.”

That got him wondering if those relatively quick changes are happening in
other places. So years later, now on the faculty at the University of
Illinois at Chicago, he gathered up some of those White Footed Mice from
the Chicago suburbs. And he went to the Field Museum of Natural History…

(sound of a cabinet opening)
… where they have a hundred years of dead mouse specimens stored in
white metal cabinets.

“Here we have trays and trays of the northern white-footed mouse.”

With a tiny caliper, he’d measure their skulls, their feet, the distance
from their eyes to their noses.

“So this one here was collected by Aikley in 1903.”

And he compared mice from before and after 1950.

“Here are some skulls, this one was collected in 1989.”

Lo and behold, these mice had grown: by more than 10% on some measures.

This phenomenon goes way beyond Chicago. Pergams measured more than 1,300
rodents from four different continents – Alaskan lemmings, Mexican
gophers, Filipino rats. Some of them got bigger, some smaller. But across
the world, most of the animals have changed over time spans thought to be
mere evolutionary eyeblinks.

The next step is to figure out why.

“You can’t get in a time machine and go back and look to see what
actually happened. So the next best thing is to see if there’s
associations or correlations with big factors.”

He found the variations correlate with changes in climate and human
population density. The exact reasons aren’t clear – more people might
mean more yummy trash for the mice to eat, for example. That’s going to
take more research to figure out, and these critters might be overdue for
some extra attention.

“One of the questions is, well, why didn’t anybody notice this before?
And I think the answer is, they haven’t looked.”

Larry Heaney curates the Field Museum’s mammal collection. He says
Pergams’s research opens up new questions about how animals respond to
changes driven by humans.

“The implication is, these animals are changing very, very rapidly. So in
a sense, it’s good: they can change. But the other side of the coin is,
they’re having to change.”

Now, the question is, is this happening in other species, too? What about
birds or bugs or plants?

“There’s been this default attitude that if you go to one place and you
capture or you observe animals or plants, that essentially there’s going
to be the same animals or plants 50 years or 100 years later. I don’t
think that’s possible to assume at all. We have to include the fact of
this change in all of our decisions, from ecology to evolutionary biology
to conservation.”

Pergams’s findings show that even the most common creatures have more to
teach us – when we ask the right kinds of questions.

For The Environment Report, I’m Gabriel Spitzer.

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Great Lakes Fish Linked to Diabetes

  • DDT was banned in 1972, but traces of it are still all over the place - including in Great Lakes fish. (Photo courtesy of Tony Arnold)

Scientists have known for a long time
that a lot of wild-caught fish have
dangerous contaminants. People
who eat fish have to weigh the health
benefits against the risks of consuming
those pollutants. Now, some research
could make that balancing act even
trickier. Gabriel Spitzer has more on
the link between diabetes… and an
infamous old chemical many assumed
was long gone:

Transcript

Scientists have known for a long time
that a lot of wild-caught fish have
dangerous contaminants. People
who eat fish have to weigh the health
benefits against the risks of consuming
those pollutants. Now, some research
could make that balancing act even
trickier. Gabriel Spitzer has more on
the link between diabetes… and an
infamous old chemical many assumed
was long gone:

In the early morning hours, anglers gather on Navy Pier in downtown Chicago.

Ray Penn is practically within casting distance of the city’s skyscrapers.

He dips his line in the waters of Lake Michigan, hoping to pull out something tasty.

“I filet ‘em, and I fry ‘em, yeah. They got a little bit of bones in ‘em, but – oh yeah. Oh, yeah, baby! I felt that!”

It’s looking like a good morning for rock bass.

“See, there’s a bass on the end of this. This is a small bass, now this guy here, he’s edible.”

Penn says he eats fish a couple of times a week, without giving it a second thought.

Down the pier, Patrick Duhan has the same attitude.

“This is the Great Lakes! It’s such a big body of water. It’s almost like the ocean. They throw tons of crap in the ocean, and there’s just too much of it to screw up.”

But, scientists say, people have managed to screw up the Lakes a fair amount.

Epidemiologists have been studying a group of sport fishers, like these guys, and charter boat captains, who eat a lot of Great Lakes fish.

Mary Turyk of the University of Illinois at Chicago measured the contaminants in their blood, and tracked their health over the years.

“We found we had 36 cases of new diabetes. And what we found was that DDE, the metabolite of DDT, was related to diabetes incidence.”

DDT.

That’s the pesticide made famous by Rachel Carson’s book, “Silent Spring.”

The chemical was banned in 1972, but traces of it are still all over the place – including in fish.

And like mercury or PCBs, it concentrates as it moves up the food chain.

So you don’t have to eat much.

“The captains were eating, I think, on average, a meal a week. One meal a week? Yeah. That doesn’t seem outlandish or anything. No, it doesn’t. It doesn’t at all. In fact, recommendations from the FDA for eating fish, based on mercury levels, are two meals per week, for pregnant women.”

So just half that much fish was linked to about a 33% increase in diabetes cases.

Turyk says it’s not clear how DDE or DDT might contribute to diabetes.

It may have to do with effects on hormones or the immune system.

“We really need more basic science to determine mechanisms that might be responsible for this.”

Another unknown is just how dangerous might this be, and when does it start to outweigh the advantages of an otherwise healthy food?

Tamara Duperval is a family doctor at a West Side Chicago clinic.

She says she still tells people to eat more fish.

“In our population, it’s really a wonder and a challenge to try to present fish as an option, when primarily the staple of diet is either chicken or beef.”

That population is mostly low-income and minority.

She says about half are overweight or obese.

From a nutrition point of view, those are exactly the people you’d want to be eating a lean, healthy protein like fish.

So Duperval is concerned about sending mixed messages.

“I do think it is confusing. And, it’s in part, I think, how we communicate crisis in this country, especially when it comes to food safety. They miss the overall preventative message, that fish is good food, and it actually provides a lot of important nutrients that are lacking in their diets.”

Health authorities often issue advisories about certain fish that have a lot of pollution.

Duperval says understanding those warnings can help people avoid some of the hazards.

But the diabetes research shows we may still have a lot to learn about these chemicals, so what’s safe to eat is getting harder to know.

For The Environment Report, I’m Gabriel Spitzer.

Related Links

Who’s to Blame for the Dead Zone

  • It is predicted that the dead zone in the Gulf of Mexico is the size of the state of Massachusetts (Photo courtesy of NASA)

About 40% of the continental U-S drains into the Mississippi River. It sends water – and pollution – from across the country into the Gulf of Mexico. A new study shows just who the worst offenders are. Gabriel Spitzer has the story:

Transcript

About 40% of the continental U-S drains into the Mississippi River. It sends water – and pollution – from across the country into the Gulf of Mexico. A new study shows just who the worst offenders are. Gabriel Spitzer has the story:

All the pollution creates a dead zone in the Gulf nearly the size of New Jersey.

Nitrogen and Phosphorus pour in and fertilize big algae blooms.

When that stuff decays, it sucks oxygen out of the water, and makes it impossible for most fish to live there.

US Geological Survey researchers say most of the problem comes from farm runoff, but the single biggest source is sewage from Chicago.

Albert Ettinger with the Environmental and Law Policy Center says Chicago water managers have to catch up with their neighbors.

“They’re gonna have to look at treatment systems which take nitrogen out of the water, and bring phosphorus down to one milligram per liter. It’s done in Milwaukee, it’s done in Cleveland, it’s done in Detroit.”

Chicago’s Metropolitan Water Reclamation District say they haven’t had a chance to look closely at the study yet, so they don’t want to comment on it.

But they don’t like being singled out.

For The Environment Report, I’m Gabriel Spitzer.

Related Links

Part One: Kicking Gas to the Curb

  • Ted Bohn, a researcher at Argonne National Laboratory in the Chicago suburbs, shows off a modified Saturn Vue with a lithium-ion battery in the rear (Photo by Gabriel Spitzer)

One of the great hopes for a green
car is the plug-in hybrid. It’s like a regular
gas-electric hybrid, only you can plug in at
night. That charge is supposed to let most
people make a typical commute without the gas engine. Carmakers and the government are throwing a lot of money at the technology – GM and Chrysler both hope to release models in the next few years. But the cars might not deliver what boosters promise. In the first part of our series on saving gas, Gabriel Spitzer
reports on what new research says about plug-in hybrids in the real world:

Transcript

One of the great hopes for a green
car is the plug-in hybrid. It’s like a regular
gas-electric hybrid, only you can plug in at
night. That charge is supposed to let most
people make a typical commute without the gas
engine. Carmakers and the government are
throwing a lot of money at the technology – GM
and Chrysler both hope to release models in the
next few years. But the cars might not deliver
what boosters promise. In the first part of
our series on saving gas, Gabriel Spitzer
reports on what new research says about plug-in
hybrids in the real world:

Ted Bohn is a researcher at Argonne National Laboratory in the Chicago
suburbs and he’s showing off his ride.

“So this a prototype, plug-in hybrid vehicle. The rear half is a 10
kilowatt-hour battery.”

It’s a modified Saturn Vue, with a big old lithium-ion battery in the rear.

That battery is like what runs your iPod – only it weighs as much as a
linebacker.

Ted Bohn: “If you actually had to drive less than 40 miles on a typical
day, you could drive the whole day without starting the engine.”

Gabriel Spitzer: “Could you drive this very vehicle 40 miles round-trip
without starting the engine?”

Ted Bohn: “Close. If you drive slowly. To be honest, 25 to 30 is what
you’ll really do – driving on a nice day downhill with a tailwind is 40,
more realistically, 25 to 30.”

The thing is, you don’t hear those little caveats from some people, like, say,
General Motors.

“You plug it in. And they expect you’ll get up to 40 miles without a drop
of gas. Wow. The Chevy Volt. I’ve heard the future, and it hums.”

That 40-mile range is based on EPA tests.

Argonne scientist Aymeric Rousseau, with backing from the government,
compared those measures to how people drive in the real world.

Based on more than 100 drivers in Kansas City, he found that 40 mile range
shrinks to about 30.

Flip on your AC, and it’s more like 20.

“People now think about, you know, your mileage may vary. Now we
have to think about, your electrical distance may vary, depending on
how you drive, and what accessories you’re using.”

Rousseau says factors like aggressive driving sap the all-electric range.

And don’t forget – we’re talking Kansas City, here.

“When we talk to people from the EPA they actually say that people in
California drive more aggressively than people in Kansas City.”

General Motors concedes the point.

Rob Peterson is a spokesman for GM.

He says driver behavior can have some affect on the all-electric range.
Though …

“I wouldn’t go as low as 28 to 32.”

He says for a reasonable driver, the Volt can still get about 40.

And how about those pedal-to-the-metal Californians? Well, he says GM
studied exactly those people.

“For 64% of the people that we tested, they would be able to finish their
day with a petroleum-free and a tailpipe-emission-free commute.”

That’s not exactly what Argonne found.

Granted, the batteries they looked at were a little smaller than the Volt’s.
Size matters when it comes to batteries.

Said Al-Hallaj teaches at the Illinois Institute of Technology.

He says carmakers could build a battery that would boost up the all-electric
range – the problem is money.

“If you’re talking about a 25% increase, you know, from 30 to 40 miles,
that could mean thousands of dollars. So that could take it out of the
price range that will make it actually practical for the industry to make
it.”

Al-Hallaj says as the technology improves, so will drivers.

People are already getting better at squeezing fuel efficiency out of their
cars.

“For the first time I see people even worried about closing the window
versus opening the window because of drag. And we’re talking about
common people here, just trying to pay attention to, if your tires are not
properly inflated, the you have prob — so people start adapt and
probably get the best out of your battery.”

So it’s not that a plug-in hybrid can’t get 40, it’s just that you need to drive
like a grandmother to do it.

But if gas prices continue to climb, we may be seeing a lot more grannies
behind the wheel.

For The Environment Report, I’m Gabriel Spitzer.

Related Links

New Pcb Chemical Found in the Air

  • One study found PCB-11 in 90% of the air samples from Chicago (Photo by Lester Graham)

A potentially toxic chemical called
PCB-11 has been found all over the air in a
major city. That’s surprising, because people
thought the chemical hadn’t been used in years.
Gabriel Spitzer reports regulators could start
looking in other cities:

Transcript

A potentially toxic chemical called
PCB-11 has been found all over the air in a
major city. That’s surprising, because people
thought the chemical hadn’t been used in years.
Gabriel Spitzer reports regulators could start
looking in other cities:

Keri Hornbuckle says not much is known about PCB-11.

That’s because no one really expected to stumble on it.

“This finding is important, and I think it’s alarming. We should find out what the
health effects are for this chemical.”

Hornbuckle is a University of Iowa professor.

She looked at air samples from all over Chicago, and found the chemical in about 90% of
the samples.

She says the source is a mystery, though it might come from paints breaking down.

“Now, it could be that in all those places where we would expect to see the other
PCBs, we’d also see this one. But it’s a surprise, because no one thought it would be
produced.”

Hornbuckle says she found PCB-11 using a new, detailed way of analyzing air samples.

Other PCBs have been linked to cancer and neurological problems.

For The Environment Report, I’m Gabriel Spitzer.

Related Links