SciTech Now Episode 405

In this episode of SciTech Now, a look into the scientific side effects of Superstorm Sandy; the development of a blight-resistant American chestnut tree; meet researchers in Tampa, Florida who are using mathematical modeling to help fight drug-resistant cancers; and a biologist studying seahorse pregnancy.


Coming up... A scientific side effect of Superstorm Sandy.

Any breach that happens on Fire Island National Seashore will ultimately be closed because of the natural processes.

The question is -- When?

...resurrecting the American Chestnut tree...

First of all, you have to develop a resistant tree, something that can survive the blight.

Strides in cancer research.

It's simply obeying the rules of living systems that all living systems obey, which means we can understand it and we can manipulate it.

...seahorse genetics...

Any type of questions that you want to ask in evolutionary biology, there is something which they do that is a little bit different from other fishes.

It's all ahead.

Funding for this program is made possible by...

Hello, I'm Hari Sreenivasan.

Welcome to 'SciTech Now,' our weekly program bringing you the latest breakthroughs in science, technology, and innovation.

Let's get started.

When Superstorm Sandy swept across much of the eastern seaboard, it left massive damage.

On Fire Island, New York, the storm left behind a breach, or land gap, that threatened local communities.

The National Park Service was left with a decision -- close the gap or wait and see what happens.

Five years later, we visit the island to see how nature took its course.

Take a look.

On a day like this, the sea alongside New York's Fire Island is calm, but when Superstorm Sandy hit in 2012, this water was whipped into a frenzy.

The storm hit during high tide, causing maximum possible damage to the area, including the long stretch of land that separates the ocean from the bay.

The sea level rose, the bay level sank, and large waves gnawed away at the sand dune that separated the two.

A path of water formed over the dune and tall waves rushed to the bay below.

The erosion created a divide in the land which became this breach in the barrier island.

In the wake of the storm, the Army Corps of Engineers estimated the cost of filling the old inlet breach to be in the millions.

The National Park Service oversees Fire Island National Seashore, so it was left with a big decision -- let the breach remain or artificially close it.

Kaetlyn Jackson is Fire Island National Seashore's Park Planner.

In the planning process, we came up with three alternatives that we analyzed, and one was to close it immediately with mechanical processes, to let it go, let nature take its course, don't touch it, don't look at it, just let it go and don't worry about it, walk away.

And then the third one was to let natural processes take their course as long as possible, and that we would know whether we need to close it based on science.

Following Superstorm Sandy, there was a lot at stake.

Residents were concerned that the breach in the barrier island could cause more flooding in nearby housing developments.

Then there was the impact to the ecosystem.

For the first time in over 100 years, water in this area began flowing freely between the ocean and Bellport Bay, a polluted section of the Great South Bay surrounding the breach.

There was pressure.

The concern about flooding impacts on the south shore of Long Island was real.

Typically, the Great South Bay has its challenges with water quality.

We have a lot of brown tides occur every year, and that's of a concern for the ecosystem.

A lot of plant life and wildlife can't survive in those kinds of conditions.

But Jackson's team knew that breaches are naturally occurring and usually close on their own over time, constantly exposed to waves that move the sand back and forth reshaping the land.

Fire Island and the barrier islands on the south shore of Long Island have historically been breached.

That's just how a barrier island system functions -- it's always moving, it's very dynamic, and part of that natural process is breaching.

That's important, because Fire Island National Seashore is a federally designated wilderness area, meaning the national park should remain unimpaired by humans as much as possible.

So the National Park Service was allowed 60 days after the storm hit to monitor and evaluate effects of the change as it related to flood risks and the stability of the ecosystem.

Charles Flagg is a professor of Marine and Atmospheric Studies at Stony Brook University.

He's been monitoring the Great South Bay since 2006.

So, in that period, they looked at our data.

We had been collecting data for the previous 6 years, and we were collecting data after the breach, and we showed that things like the tide range had not changed.

Not only that, but the pollution in Bellport Bay had actually improved from the influx of ocean water.

It was clear that the exchange between bay and ocean water was clearing up at least Bellport Bay.

So Bellport Bay was much cleaner than it had been for the past 30 years.

We can say that there has been an increase of species and species richness.

So there are more animals using the area in greater numbers than before.

Because the ocean and the Great South Bay is mixing water, the temperature is a little bit warmer in the winters, cooler in the summers in the bay.

It has increased the salinity locally in the bay, and also affected a little bit of the distribution of how water moves throughout the bay.

It's not a good or bad thing.

It's a change, and depending on the species you are, it might be a good or bad thing, but overall, it's a natural process that we're excited to see and continue to research.

So the park service left the old inlet breach alone.

Now, years after Superstorm Sandy, Jackson says her team still meets monthly to discuss engineering plans for closing the break in the barrier land.

The idea is that any breach that happens on Fire Island National Seashore will ultimately be closed because of the natural processes.

The question is -- When?

So we have this planning process to give us different options in case we start seeing impacts to the natural and cultural resources to Fire Island, and negative impacts to the south shore of Long Island, so if there were flooding impacts or damage.

By its very nature, the breach is constantly shifting, so if it does need to be closed, there is no way of knowing how large the gap would be at that point, or even its precise location.

That's why regular monitoring is key.

So any design will have to be done when we know we have to close it based on the size, the location, the depth, and all of those other factors.

The American Chestnut tree was once a staple of the U.S. landscape, numbering over a billion, but by the 1950's, a fungus had eliminated many of the species.

Now, after 35 years of research, Professor William Powell of the State University of New York College of Environmental Science and Forestry in Syracuse has developed a blight-resistant American Chestnut tree to restore the population, he hopes.

How did we get from hundreds of millions of trees to where we are today?

Well, what happened was that people started importing Asian Chestnuts about a century ago, and they did it for several reasons -- for orchards or yard trees or whatever.

But when they brought those over, they didn't realize that when you bring over a tree, you're not just bringing the tree over.

You're bringing all of the microbes that are on that tree.

And it turns out that there was one fungus on there that was a pathogen that the Asian trees could survive, but the American Chestnut was very susceptible to.

The fungus is happy -- it just finds a new population to feast on.

That's right, more food, and then it just spreads around.

So it came across and basically jumped off of the Asian Chestnut trees onto the American Chestnut trees.

It was actually first described at the Bronx Zoo in 1904, and from there spread throughout the range, as you said, killing billions of the largest trees in the forest, the American Chestnut.

And within 50 years, basically, they were functionally extinct.

Chestnut was such a common source, at least wood-wise.

Most of your decks on your homes were Chestnut.

It was very good for a woodworker to work with, right?

Actually, they used to say it would follow you from the cradle to the grave, because it was used to make cradles and graves.

In fact, as I was coming in today, I was at the railway station, and their benches there were all made out of American Chestnut.

So it was used for all kinds of purposes.

I'm thinking 'Chestnuts roasting over an open fire.'

It's so American, and the idea that the American Chestnut is where it's at... So, you've been in the lab mixing cultures of trees over time?

Yeah, so, I work very closely with the American Chestnut Foundation, and they first started what's called a backcross breeding program, where they would cross American Chestnuts with the Asian species.

So they mixed the two genomes, and then they backcross it to American to try to sort out all of the genes they don't want to have, but keep the resistance genes in.

About 6 years after that started, the New York chapter of the American Chestnut Foundation came to Dr. Maynard and myself at the College of Environmental Science and Forestry to see if we could take some of the newer approaches using genetic engineering to just put the genes in for resistance.

And that's how it got started.

About 27 years ago at ESF we started looking for genes, started developing methods to actually move genes into the tree.

That backcrossing that you were talking about, when you decided to cross these different genes, you want to figure out how not to carry on the negative traits?


So that's the reason why we started using genetic engineering in addition to traditional breeding, because in traditional breeding, what you do is you actually bring in all the traits and then you have to weed them out.

Some of the traits that you don't want to have -- the Asian Chestnuts are much shorter in height, typically growing only 40 to maybe 60 feet, and American Chestnuts would grow 80 to over 100 feet in height.

And that's important because American Chestnut was a canopy tree, and for it to reach a canopy in the eastern forest, it has to grow that tall.

So if you shorten it a little bit, it will no longer be a canopy tree.

Is there a way to bring this tree back?

I mean, what are the areas where we would start?

Okay, so, first of all, you have to develop a resistant tree, something that can survive the blight, and that's what we did.

So we now have a tree that we just added a single gene that confers blight resistance, and they get that out into the field.

One of the first steps we have to do is actually work with the federal government to get our regulatory approval.

We work with the USDA, EPA, and FDA for that.

After that, we're going to start a breeding program where we try to rescue the genetic diversity of the trees that are still surviving.

There are still a few million American Chestnut trees out there, and they're a diverse group.

So we can actually cross our trees that are blight-resistant with them and kind of get those genotypes back into a restoration population.

Are there specific areas?

Like when you look out in Appalachia, there are huge swaths of mountain tops that have been removed for coal mines that are basically shut down, but you're still left with a pretty big and barren landscape.

Would these kind of trees work?


As a matter of fact, one on the things we don't want to do in the restoration program is cut down some really nice oaks and stuff like that to replace them with Chestnuts.

Instead we would rather look at places that are already devastated, that do not have the forest there anymore, and mine land reclamation is actually a great place to start.

These are places with mountaintop removal type things, but you want to turn it back to a natural ecosystem.

Those places we could actually put Chestnut back, not by itself, but along with other species that it normally would co-habitate with and kind of do a restoration on those lands and kind of let it spread from there.

So how long would it take to get it?

Obviously we have less land now that is pure forest than we did 50 years ago where these Chestnuts were, right?

But to try to bring the American Chestnut back to a place where it is vibrant, competitive, and blight-resistant.

So it's not going to be quick.

Chestnut is not a weed.

It does not spread quickly, probably only a couple miles per hundred years on its own.

So it's really going to depend on people planting them.

We really want to get people involved, not only our generation, but the next generation, and the following generation, because it's a century project to get it really back to where it was before the blight.

All right.

William Powell, thanks so much for joining us.

Thank you.

Scientists have made great strides in developing drugs to fight cancer, but some cancers have now become resistant to drug therapies.

In this segment, we meet researchers from the Moffitt Cancer Center in Tampa, Florida, who are using mathematical modeling to help fight drug-resistant cancers.

Dr. Alexander Anderson is a mathematical biologist who spent 12 years studying mathematical models in cancer at the University of Dundee in Scotland.

I moved my whole group, my family, to Moffitt because I really believed in the power of integration.

To be inside the cancer center meant I was going to be with the biologist and the clinicians that I wanted to collaborate with, and I thought IMO, then, as a truly integrated department, would drive the understanding of what mathematical models could do for cancer research.

Dr. Anderson's team of physicists, computer scientists, and mathematicians have worked with clinical and research oncologists at the Moffitt Cancer Center in Tampa for the past 8 years.

This kind of team science perspective, or integrative perspective, I believe, is really the future of science in general, but I think it's particularly the future of how we're going to manage and treat cancer.

Cancer's resistance to certain therapies have kept researchers and clinicians from being able to eradicate the disease.

My primary interest is in how cancers evolve, how you go in the transition from normal to cancer, and then how cancer cells evolve resistance when you give therapy to them.

For 50 years, oncologists have blasted tumors with as maximum a dose as possible.

What you then get is a phenomenon called competitive release, which means that you're killing all of the cells except for the ones that are resistant, and we're removing all of their competitors.

This left the resistant cells to grow unabated, as if it had magical powers.

It's just a population that evolves.

There's nothing evil about it, there is nothing about it that is magic.

It's simply obeying the rules of living systems that all living systems obey, which means we can understand it and we can manipulate it.

Through mathematical modeling, scientists can now develop ways to predict the growth of a tumor.

We have normal cells in the background there in gray, we have the tumor in the middle in green, and these are little, white blood vessels.

And what we're interested in understanding is how does that tumor grow and invade into this tissue, and evolve.

So I'm going to show you a little movie here that shows the evolution of the cancer, and what you see is initially it becomes a little bit more acidic as resistant, and you have this green rim of these metabolically normal cells, but inside, where it's starved of oxygen, there are these purplish cells.

And eventually some of these purple-pink cells breach that nice metabolic boundary and rapidly invade the surrounding tissue.

Anderson and Gatenby have worked with the oncologists at Moffitt to create new strategies for fighting cancer.

Instead of trying to kill all of the cancer cells when you know you can't do that, the goal is to manage it.

So, in the patients, what we try to do is to keep their cancer under control, not using the maximum dose possible, but the minimum dose necessary.

What we then do is we tend to use evolutionary dynamics to control the tumor rather than letting the tumor use evolution to beat our therapy.

Developing new research and treatment plans didn't come easy for the team.

It took a while for the mathematicians to become grounded in the reality of biology and oncology, and it took a long time for the biologists and oncologists to recognize that the mathematicians were offering them insights that they wouldn't get otherwise.

In the end, out of it comes what seems like a feasible trial that you could try.

And then it's very scary to start seeing patients being treated, not entirely knowing what's going to happen.

One of those patients for the clinical trial is Robert Butler, who was first diagnosed for prostate cancer in 2008.

I came along to the Moffitt, and I had 8 weeks of radiation treatment.

And in 2016, Robert became a candidate for the new trial on managing cancer in his body.

He has received three rounds of treatment over the past year.

So clearly, if you only show these cancer cells once in a while, this integer, instead of continuously, it seems to the layman that that seems a pretty good idea to at least delay the cancer cells from seeing that this integer is a pretty deadly thing now to combat it.

So I was very pleased to go on it.

There was never any doubt that I would do so.

Because of the complex nature of cancer, math has been shown to be a critical tool in managing its treatment.

One of the key features of mathematics is that with great simplicity, you can produce amazing complexity.

And so that ability of mathematics is something, I think, that is not well-understood, but is something that we should really cherish and be proud of.

I'm very sensitive to trying to do the best for patients, and I'm always amazed by how remarkable they are.

I'm happy to be able to make whatever contribution that I can.

And I see that, really, I believe, and one of the reasons why I came to Moffitt, is that I think that is the future of how we're going to treat cancer.

We're going to have a mathematical model for every patient's cancer, and that will be how we decide what to treat, when to treat, and how long the treatment should be.

Although it's well known that seahorses and their cousins the pipefish are the only vertebrates where males become pregnant, researchers have only begun to understand how this unique adaptation works.

By studying their behavior and sampling molecules within the male's pouch, biologist Tony Wilson and his lab at Brooklyn College in New York have found that seahorse pregnancy may have a deeper genetic link to other forms of pregnancy than previously thought.

Our partner 'Science Friday' brings us the story.

Anybody who has ever seen a seahorse or a pipefish knows that they look very different from most other fishes.

They have bony plates across their body.

They've lost pelvic fins.

They've lost their teeth.

And most notably...

All the members of this group have one or another form of male pregnancy.

There are no other vertebrates that do male pregnancy.

None, not one, and this makes them a fertile research subject.

Any type of question that you want to ask in evolutionary biology, there is something which they do that is a little bit different from other fishes.

Dr. Tony Wilson is an associate professor at Brooklyn College, where he researches seahorses and pipefish, a group of 300 species who have evolved male pregnancy in some form or another.

So, we are involved in a whole variety of different projects.

I'm working on genome sequence.

We're doing studies on hormonal regulation of pregnancy, and studying the behavioral interactions of males and females.

All in the hopes of discovering how male pregnancy works.

That these males swim against the evolutionary tides to carry their own young requires a huge sacrifice of time and energy for their brood.

Which he could otherwise be using for other purposes, including mating with other individuals.

But there are clear ecological advantages, as well.

He has complete confidence in paternity.

All of the eggs which are within a male's pouch are the genetic offspring of that male.

He can even benefit from changing horses in midstream.

The males can absorb the energy that is contained within those eggs, and in theory, they could actually not fertilize the eggs with the female and wait for another, more attractive female.

So the males now have complete control.

The mating rituals of seahorses can be just as nuanced as their pregnancies.

When a male and a female encounter one another, there is a mating dance which will take between three and four days.

The two will lock tails and swim side by side, eyeing one another, until...

The male will point his head upwards, and that's an indication that he is going to start to swim upwards.

They'll do a tandem swim vertically in the water column.

And when they have reached perfect alignment...

The female will be above the male, and will transfer her eggs into the male's pouch.

As the eggs are being transferred to the males, the males fertilize them.

The eggs then are either stuck on the outside of the body of the male or the eggs are deposited into a completely enclosed pouch.

As in the case of the seahorse, and unlike fathers of other species who might carry or protect their young, a male seahorse provides some special care for it's brood.

So the embryos will implant in the brood pouch wall.

So there is a close connection between the male's blood supply and the pouch.

And then the male regulates the internal environment.

He provides oxygen to the embryos during their development.

There is suggesting that he provides energy, he regulates the salinity such that when the offspring are released, the salinity within the pouch and outside the pouch is identical.

And finally, he labors his offspring into the world.

He has contractions which are very similar in terms of what we see in terms of labor in humans, and once the offspring are released, you have little baby seahorses which are completely free-living.

Although male seahorse reproductive roles have been flipped, Dr. Wilson's lab has shown that the similarities between their pregnancy and mammalian pregnancy may run deep.

What we wanted to do is to sample males at various stages throughout pregnancy.

And then we look at the genes that were active at these various stages of the pregnancy.

By sequencing the RNA within the seahorse's pouch...

We discovered that a good proportion of the genes, about 5% to 10% of the genes, which are involved in male pregnancy in the seahorse are actually also involved in mammalian pregnancy, which frankly surprised all of us.

One important group of genes they identified are believed to regulate a hormone called Prolactin.

Which plays a very important role in mammalian pregnancy.

As its name implies, Prolactin helps mammal mothers to produce milk after birth.

What a male seahorse uses it for...?

Jury is still out.

Dr. Wilson and his lab are now working to solve that question, and he's got some theories.

Working hypothesis at the moment is that Prolactin was regulating the salinity within the male's pouch.

And for Dr. Wilson, the innovative usage of a pregnancy hormone by a male seahorse isn't hard to conceive.

When we look at animals, animals look so different from each other, and they do things in such different ways, but it actually makes a lot of sense when you think about it.

It doesn't make sense to invent something completely independently if you have mechanisms that could do it in a slightly different way.

So seahorse pregnancy may turn out to be pretty unoriginal, and exactly what you were expecting, in other words, just like a dad joke.

And that wraps it up for this time.

For more on science, technology, and innovation, visit our website, check us out on Facebook and Instagram, and join the conversation on Twitter.

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Until next time, I'm Hari Sreenivasan.

Thanks for watching.

Funding for this program is made possible by...