From Ants to Grizzlies: A General Rule for Saving Biodiversity | HHMI BioInteractive Video
Summary
TLDRThis script narrates the journey of Edward O. Wilson, a renowned biologist, from his childhood fascination with ants to his pivotal role in conservation science. Wilson's studies on island biodiversity led to the discovery of the species-area relationship, predicting species distribution based on habitat size. His work inspired experiments like the Amazon rainforest fragmentation study, which underscored the impact of habitat size on species, particularly larger ones. The script also highlights conservation efforts such as the Yellowstone to Yukon initiative and indigenous-led projects, emphasizing the importance of wildlife corridors and crossings to maintain biodiversity amidst human expansion.
Takeaways
- đż The Earth was once rich in biodiversity, but human expansion has led to shrinking and fragmented habitats, threatening wildlife.
- đŠ The story of conservationist Edward O. Wilson began with his childhood fascination with ants in Mobile, Alabama.
- đ Wilson's research on ants led him to Harvard University, where he focused on their dominance and the mysteries of their species distribution.
- đ Wilson discovered a 'rule of thumb' relating the number of species on an island to its area, which he later tested through experiments.
- đ He used the volcanic eruption of Krakatoa as a natural experiment to understand species repopulation on devastated islands.
- đŠ In the Florida Keys, Wilson and his team conducted a controlled experiment to observe species recolonization after eradicating insects from mangrove islands.
- đł The Amazon rainforest experiment confirmed that habitat fragmentation affects biodiversity, with larger species being more vulnerable.
- đș Conservation efforts, such as the Yellowstone to Yukon Conservation Initiative, aim to connect and protect habitats to allow wildlife to roam.
- đ Indigenous lands in Montana have implemented wildlife crossings to reconnect habitats and reduce the impact of human infrastructure on wildlife.
- đ The insights gained from studying ants and island ecosystems are now guiding global conservation efforts to protect a wide range of species.
Q & A
What was the significant change in Edward Wilson's life when he was seven years old?
-At the age of seven, Edward Wilson had a fishing accident that resulted in the loss of vision in his right eye, leaving him with vision in only one eye.
What subject did Edward Wilson choose to study due to his unusual acuity in his remaining eye?
-Edward Wilson chose to study insects, particularly ants, due to his heightened visual acuity in his remaining eye after losing vision in the other.
What was the main subject of Edward Wilson's doctoral thesis at Harvard University?
-Edward Wilson's doctoral thesis at Harvard University focused on ants, which he considered the dominant insect species on Earth.
What did Edward Wilson discover about the relationship between island size and the number of species?
-Edward Wilson discovered a 'rule of thumb' where an island that was 10 times bigger had twice as many species, indicating a mathematical regularity between island size and species count.
How did the volcanic eruption of Krakatoa in 1883 provide a unique opportunity for ecological study?
-The volcanic eruption of Krakatoa in 1883 wiped out all life on the island, making it a perfect 'laboratory' for studying how species colonize and recreate an ecosystem.
What experiment did Edward Wilson and Daniel Simberloff conduct in the Florida Keys to test the species-area rule?
-Edward Wilson and Daniel Simberloff conducted an experiment in the Florida Keys where they obliterated all insects on tiny mangrove islands to observe which species would return, testing the species-area rule.
What was the outcome of the Amazon rainforest fragmentation experiment in terms of biodiversity?
-The Amazon rainforest fragmentation experiment showed that smaller forest patches supported fewer species, and larger species like jaguars, harpy eagles, and spider monkeys were more affected by habitat shrinkage.
How do wildlife corridors help in conservation efforts?
-Wildlife corridors help in conservation by creating larger, continuous wilderness areas that allow animals to move freely, which is essential for the long-term survival of species with large home ranges.
What is the significance of the wildlife crossing structures in the Yellowstone to Yukon (Y2Y) region?
-The wildlife crossing structures in the Y2Y region, including overpasses and underpasses, are part of a robust system that allows animals to safely cross human-made barriers, thus maintaining connectivity in their habitats.
How do indigenous efforts in Western Montana contribute to habitat connectivity?
-Indigenous efforts in Western Montana, such as the construction of bridges and passages over and under highway 93, contribute to habitat connectivity by providing safe crossing points for wildlife, thus reconnecting fragmented habitats.
What is the cultural significance of wildlife movement across the landscape for the Confederated Salish and Kootenai tribes?
-For the Confederated Salish and Kootenai tribes, wildlife movement across the landscape holds cultural value as it represents a connection to their tribal people and the importance of ensuring the safe flow of wildlife, including the dispersal of species and their young.
Outlines
đż Early Passion for Nature and the Study of Ants
The script begins with a reflection on the vast wilderness that once covered Earth and the challenges faced by wildlife due to human expansion. It introduces Edward Wilson, a young boy from Mobile, Alabama, whose love for ants would lay the foundation for his future work in conservation. Despite losing an eye in an accident at age seven, Wilson developed a keen interest in natural sciences, particularly entomology. His fascination with ants led him to Harvard University, where he focused on these insects for his doctoral thesis. Wilson's early adventures in the South Pacific helped him observe the correlation between island size and species diversity, which would later become a significant part of his research.
đ Island Biodiversity and the Species-Area Relationship
Wilson's research took a significant turn when he studied the biodiversity of islands, particularly after the volcanic eruption on Krakatoa in 1883. The island, devoid of life, became a natural laboratory for Wilson to understand species colonization and ecosystem recovery. He used the island as a case study to predict species repopulation based on the species-area relationship he had observed. Inspired by this, Wilson conducted a controlled experiment in the Florida Keys, where he and his graduate student, Daniel Simberloff, obliterated insect populations on mangrove islands to study recolonization. They found that islands regained a similar number of species, but with different compositions, confirming Wilson's hypothesis about species-area dynamics.
đŸ Habitat Fragmentation and Its Impact on Wildlife
The script then shifts to discuss the impact of habitat fragmentation on wildlife, particularly larger species that require more extensive areas to survive. The Amazon rainforest experiment highlighted how smaller forest patches support fewer species, with larger species being more affected due to their extensive range requirements. Conservationists in the Rocky Mountains also recognized the need for larger habitats to support species like wolves. The script introduces the Yellowstone to Yukon Conservation Initiative, which aims to connect and protect habitats over a vast stretch of land, emphasizing the importance of wildlife corridors for species movement.
đł Reconnecting Habitats and the Role of Indigenous Lands
The final paragraph discusses efforts to reconnect habitats, such as the construction of wildlife crossing structures over and under highways in Western Montana. These structures, advocated for by the Confederated Salish and Kootenai tribes and wildlife biologists, allow animals to safely cross busy roads, reducing habitat fragmentation. The script highlights the success of these efforts through the use of trail cameras that capture various species utilizing the crossings. The narrative concludes with a reflection on the importance of conserving natural habitats, drawing on the insights gained from Wilson's work with ants and the broader implications for global conservation efforts.
Mindmap
Keywords
đĄBiodiversity
đĄHabitat Fragmentation
đĄSpecies-Area Relationship
đĄIsland Biogeography
đĄConservation
đĄEcosystem
đĄWildlife Corridors
đĄInvasive Species
đĄEndemism
đĄHabitat Restoration
đĄEcological Succession
Highlights
The Earth was once rich in biodiversity, but human expansion has led to shrinking and fragmented habitats, threatening wildlife.
Edward Wilson's childhood fascination with ants in Mobile, Alabama, laid the groundwork for his future contributions to conservation.
At seven, Wilson was blinded in one eye in a fishing accident, which led to his developing a keen interest in entomology.
Wilson's doctoral thesis at Harvard University focused on ants, the dominant insect species on Earth.
During his first expedition in the South Pacific, Wilson observed a correlation between island size and species diversity.
Wilson's research suggested a 'rule of thumb' linking the number of species to the area of an island.
The volcanic eruption of Krakatoa in 1883 provided a natural experiment for studying species recolonization.
Wilson predicted the number of species that would repopulate Krakatoa based on the species-area rule, which was confirmed by data.
To test the species-area rule, Wilson and his team created a controlled experiment in the Florida Keys, dubbed 'mini-Krakatoa'.
The experiment in the Florida Keys showed that islands, when cleared of species, would refill with different species, confirming the species-area rule.
The Amazon rainforest experiment in 1979 demonstrated that habitat fragmentation affects larger species more significantly.
Conservationists realized that even national parks might not be large enough for species with extensive home ranges.
The Yellowstone to Yukon Conservation Initiative was established to connect and protect habitats over a vast stretch of land.
Creating wildlife corridors and crossing structures, such as overpasses and underpasses, helps maintain connectivity for wildlife.
The Confederated Salish and Kootenai tribes worked with biologists to build bridges and passages over highway 93 to reconnect habitats.
The use of wildlife trail cameras on overpasses and underpasses helps monitor the success of habitat connectivity projects.
Edward Wilson emphasizes the complexity, preciousness, and urgency of conserving the natural world.
Transcripts
[MUSIC PLAYING]
SPEAKER: Not long ago, most of Earth
was covered in vast wilderness, rich in biodiversity.
As human populations expand, habitats
are shrinking and becoming more fragmented.
Many animals now face a new kind of struggle to survive.
How can we protect the wildlife and wild places that remain?
One of the foundations of conservation now being
applied across the world began with the dreams of a young boy
in Mobile, Alabama, and of all things, his love for ants.
[BANJO MUSIC]
EDWARD WILSON: The great thing about living in old Mobile
when I was a boy was I could, in any direction,
be within 20 to 30 minutes of natural areas, some of them
quite still wild.
I could study butterflies.
I could collect snakes.
I could learn everything.
And I did it, usually, all by myself as a kid.
SPEAKER: But when Wilson was just seven years old,
a terrible accident changed the course of his life.
EDWARD WILSON: I was fishing one day for pinfish.
And I pulled one up too fast.
A sharp, needle-like fin hit my right eye.
And ultimately, I was blinded.
So I would grow up, from then on,
with vision in only one eye.
But what I did discover was I have an unusual acuity
in my remaining eye.
So I picked the subject I wanted to study--
insects.
It never occurred to me that I would ever
be anything but a naturalist.
Entomology, insects-- that was my thing.
SPEAKER: One group of insects would
take Wilson from the backwoods of Alabama all
the way to graduate school at Harvard University.
EDWARD WILSON: Ants are the dominant insect
species on Earth.
But when I started my career, we really
didn't know much about them.
In 1951, when I went up to Harvard,
I knew I would make them the subject of my doctoral thesis.
And ever since, I've placed ants at the center
of my professional life, the focus of a near obsession.
SPEAKER: In 1955, Wilson embarked
on his first great adventure, to collect and identify
insects across islands in the South Pacific.
EDWARD WILSON: And it was during that period of exploration
I was also thinking about why different islands have
different species and different numbers of species.
SPEAKER: Wilson tallied the number of ant species
on each island.
And when he plotted them against the area of the island,
he noticed an interesting relationship.
An island that was 10 times bigger
had twice as many species.
On islands elsewhere, reptiles and amphibians
showed a similar relationship.
EDWARD WILSON: There actually were
rules, mathematical regularities,
that nobody, up until the 1960s, had tried to reason out
why it was like that.
SPEAKER: Wilson discovered what he called "a rule of thumb,"
a general relationship between the number of species
on an island and its area.
If this rule was indeed general, Wilson
figured that if all the species were removed from an island,
then the same number of species might repopulate it.
But how could he test that?
He suddenly remembered an extraordinary event.
EDWARD WILSON: On August 27, 1883,
one of the greatest volcanic eruptions ever recorded
laid waste to the Indonesian island of Krakatoa.
Life on the island had been completely wiped out.
That tragic event made Krakatoa the perfect laboratory
in which to find out how species colonized and recreated
an ecosystem.
SPEAKER: For decades after the eruption,
naturalists recorded the birds that returned
to the devastated island.
[BIRDS COOING]
Based on the number of bird species on other Pacific
islands, Wilson predicted the number
of species that would repopulate Krakatoa.
The data from the naturalists matched his prediction.
EDWARD WILSON: But then it dawned on me.
How many lifetimes is it going to take
to really have replications of this experiment?
SPEAKER: A rare event like Krakatoa
was unlikely to happen during Wilson's life.
He needed a way to test the species-area rule
in a controlled experiment.
EDWARD WILSON: So I decided to create my own mini-Krakatoa
in the Florida Keys.
We went down to Florida, to Florida Bay,
where there are thousands of little mangrove islands,
these little dots on the map.
SPEAKER: Mostly insects lived on these mangrove islands.
If Wilson and his graduate student, Daniel Simberloff,
could obliterate all the insects on the tiny islands,
they could observe the species that returned.
EDWARD WILSON: We got an exterminator from Miami.
We covered a number of islands so they
could be fumigated by the same technique used
to fumigate warehouses in order to eliminate
all of the creatures on this little island.
Please don't think of me as a destroyer of biodiversity.
SPEAKER: Within several months, most of the islands
were crawling with a similar number of species
as before the fumigation.
EDWARD WILSON: Remarkably, it filled up with species.
But they were mostly different species.
SPEAKER: Simberloff also tested what
happened when animals were restricted to a smaller area.
To do that, he sawed off parts of mangroves.
As an island got smaller, the number of species
decreased, just as the species-area rule predicted.
EDWARD WILSON: The results strikingly
confirmed our hypothesis.
We figured out how we can predict
the number of species that will arrive and live on an island.
SPEAKER: Wilson thought that the lessons from these tiny islands
had very big implications.
EDWARD WILSON: The world can be viewed as a series of islands
fragmented by human beings.
SPEAKER: Farms, roads, and towns are steadily shrinking
Earth's remaining natural habitats,
creating islands in a sea of humanity.
Do these islands on land behave the same way
as Wilson's tiny mangrove islands?
To find out, in 1979, conservation scientists
launched a landmark experiment in the Amazon
by carving the rain forest into different sized patches
and monitoring biodiversity.
KELLEN GILBERT: One of the most important things
that the project found is that these fragments really
do work as islands.
They function as islands of forest
that's surrounded by pasture.
The effects of fragmentation are really strongly felt
by the monkey species.
They spend all their day, day and night, up in the trees.
It's very rare to see them come to the ground.
And when you start to isolate the forest resulting
in these forest fragments, then these monkeys
basically get stuck in there.
There are only two or three species
in these little islands, as opposed to six
in the continuous uncut forest.
SPEAKER: The smaller forest patches
supported fewer species.
But the experiment also revealed an important new finding,
something Wilson could not have seen
on his mangrove islands that only contained tiny animals.
KELLEN GILBERT: The larger species are more affected.
Just because they have larger range requirements,
they need much more area, so things like jaguars, harpy
eagles, spider monkeys.
When the forest is cut and then we
leave these little isolates of fragments,
then we start to see some of the species dying out.
SPEAKER: The Amazon experiment sounded an alarm.
It showed that shrinking a habitat
has a greater effect on larger animals.
Conservationists elsewhere, such as in the Rocky Mountains,
were also discovering just how much area some animals need.
JODI HILTY: So we had this wolf called Pluie the wolf.
She started just below Banff National Park.
And she moved 100,000 square kilometers.
She moved across two provinces, three states,
30 different jurisdictions.
It was that kind of movement of animals
that caused conservationists and scientists to go, wow.
We're not really thinking at the right scale.
SPEAKER: Biologists realized that even national parks might
not be big enough to support species with large home ranges.
JODI HILTY: Wildlife, particularly bigger animals,
they need room to roam.
Well, they can't do that if there's
too many human activities and if they
don't have the ability to move through that sea of humanity.
SPEAKER: But if protected areas are hemmed in,
how can you make them any bigger?
JODI HILTY: I worked for an organization
that's called the Yellowstone to Yukon Conservation Initiative.
It was founded in 1993 with a vision
of connecting and protecting habitat
from down in Wyoming, all the way to the Arctic
Circle and the Yukon, a 3,200 kilometer stretch of land.
SPEAKER: One way Y2Y reconnects existing protected habitats
is by purchasing land to create a wildlife corridor, a larger
continuous wilderness through which animals can move.
JODI HILTY: Our challenge, in order
to conserve these species over the long term,
is to make sure that we resolve those potentially fragmenting
areas and try and reconnect them and keep them connected.
SPEAKER: Another important way to link habitats
is taking place on indigenous land in Western Montana.
WHISPER CAMEL-MEANS: We're here at the south end
of the Flathead Indian Reservation.
This is the area where highway 93
cuts through a really continuous block of forested area.
Highway 93 is a pretty big barrier with a lot of traffic.
And so previously, animals had to try
to run across this highway.
[HORNS HONKING]
SPEAKER: The Confederated Salish and Kootenai tribes,
with the wildlife biologists here,
successfully lobbied for the construction
of bridges and passages to connect
habitat severed by highway 93.
WHISPER CAMEL-MEANS: We're in a really unique area
because we have the overpass over here that allows animals
to walk over the highway.
And then we also have associated underpasses here
that let species walk under.
Now that we've come into the underpass,
the sound is different.
The traffic volume is kind of loud.
But when you get in here, it's muffled.
It's not as loud.
You can hear the creek running through the middle.
It sounds more natural.
In the middle of the summer, wildlife will just
lay in these things for hours.
They'll be drinking water.
They'll just be resting.
They can see things coming toward them,
so they have some ability to see predators approaching.
And it's just kind of cozy for an animal.
A crossing structure like this makes a connection
between those two patches of land
so that animals can move through and essentially
makes them one big area.
SPEAKER: Tracking which animals use
them is a measure of the project's success.
WHISPER CAMEL-MEANS: I'm setting up one of our wildlife trail
cameras on the overpass.
These cameras are great, and they're
really useful because they pick up motion.
That's what sets them off and sets them to take photos.
[CAMERA CLICKS]
We get mountain lions walking through this structure,
black bear, bobcats, whitetail deer.
JODI HILTY: In the Y2Y region today,
we have at least 106 wildlife crossing structures, overpasses
and underpasses, that are dedicated for wildlife.
It's one of the most robust crossing systems
in any landscape in the world.
SPEAKER: Because of the efforts of communities
living alongside the wildlife, the species in this region
have the room to roam.
WHISPER CAMEL-MEANS: Wildlife moving across the landscape
has a cultural value, that we care the wildlife
that we're connected to as a tribal people
safely flow across the landscape,
that we think about their energy, their species,
their young being able to disperse all over.
So this was really a mix of science,
politics, and tribal culture values
that made what we have here so special
and so important to our people.
SPEAKER: Insights that began with ants on faraway islands
are now guiding efforts to protect species great and small
across the globe.
EDWARD WILSON: In all my work now,
I want to drive home to people just
how complex the natural world is, and just how precious,
how much there is still to be discovered,
and how urgent it is that we conserve what is left to us.
[BIRDS CHIRPING]
[MUSIC PLAYING]
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