Thinking Big: Protecting Ecosystems Could Begin with the Restoration of the Largest Species – Gill

Animal drawing

Illustration by Amanda Kahl Extinct North American species and those that exist today are juxtaposed near the North and South Bubble mountains in Acadia National Park. Clockwise from top left: a musk ox, short-faced bear, woodland caribou, American lion, giant beaver and woolly mammoth, with today’s moose. At the end of the last Ice Age, half of the large mammals went extinct. Large herbivores play key roles and when they’re gone, ecosystems suffer, says paleoecologist Jacquelyn Gill.


Jacquelyn Gill puts the dead to work.

She pores over fossils, pollen and spores from the Earth’s past, extracting clues about ecosystems through deep time and over vast regions of the planet. Clues from the departed can help the living, says the assistant professor with the University of Maine School of Biology and Ecology, and the Climate Change Institute.

The dead are not just a collection of bones and long-dead things in a drawer, she says. Rather, extinct animals and plants are naturally concluded experiments of the past, and teasing apart bits of material from what plants and animals left behind can inform current conservation efforts.

The past matters and is a great resource to teach people about the world today, says Gill.

“If we understand the consequences of extinction better, we might be able to motivate ourselves to manage biodiversity better,” she says.

While resilience of fauna and flora throughout the paleorecord gives Gill hope for the future, she says climate change is creating a planet of winners and losers.

Climate change predicted in the next century will push the planet outside anything we’ve experienced in hundreds of thousands of years, or even longer, Gill says, and in many cases it’s predicted to happen faster than the recent past. Saving a million species from extinction can be overwhelming, especially with so much uncertainty, she says.

According to Nature news feature editor Richard Monastersky’s 2014 article, 41 percent of all amphibians on the planet face extinction, as do 26 percent of mammal species and 13 percent of birds.

What 05 matter more than losing species in general is the specific species we’re losing, Gill says.

For instance, the African elephant population is estimated to be fewer than 500,000. According to National Geographic, in 1930, there were 5 million–10 million of the majestic plant-eaters that can grow to 13 feet and 14,000 pounds.

“If you want to protect an entire ecosystem, start with protecting its largest inhabitants,” Gill says. “At the end of the last Ice Age, we lost half of the mammals in North America larger than a German shepherd, and the forests and grasslands they inhabited noticed the difference.

“Large herbivores, from mammoths to elephants, play special keystone roles in ecosystems. When we lose them, we lose all the services they provide — from spreading nutrients to creating patches where many different plants can thrive,” Gill says.

In the absence of these large herbivores, there are cascading effects across ecosystems, including an increase in the incidence of wildfires.

j gill portrait

Jacquelyn Gill

For some conservationists, wildlife biologists and ethicists, de-extinction — resurrection of species that humans drove to extinction — 05 be a viable (though controversial) way to protect a variety of the planet’s animal and plant life.

“Like Jurassic Park, but actually possible,” says Gill, a paleoecologist, which she compares to being a forensic scientist. Gill studies the ecology of the past, and geographical distribution of living things through space and time.

Due to developments in genetics and stem cell technology, as well as recovery of ancient DNA and reconstruction of lost genomes, Gill says it’s possible that shaggy-coated, 15-ton animals with 15-foot tusks — similar to woolly mammoths — could again roam the Earth.

In spring 2015, a team of scientists in Sweden completed the woolly mammoth genome by extracting DNA from the remains of a woolly mammoth that lived more than 40,000 years ago. Another team at Harvard is working to insert the DNA into elephant stem cells to give elephants mammoth-like traits like blood with a kind of antifreeze.

“I think climate change is really going to force us to be creative with conservation solutions,” says Gill. “This 05 be the kind of creative solution we need to think beyond the level of the species and protect biodiversity as a whole.”

However, Gill cautions that de-extinction needs to be driven by science and a strong research agenda, and include the public as a stakeholder.

So too, does rewilding — or returning keystone species into areas where they’ve been absent for some time.

The reintroduction of gray wolves into Yellowstone National Forest in the 1990s is one example of rewilding. By the 1930s, hunters in Yellowstone had wiped out the gray wolf, which then affected other parts of the ecosystem. The elk population exploded. When they feasted on willow, aspen and cottonwood trees, land degradation folloincluding erosion and a lack of food for beavers.

Since the reintroduction of wolves in the 1990s, scientists say the elk population has been reduced and willow stands have rebounded, providing songbird habitat. There’s been more food for beavers, too, which has resulted in new dams and cold-water ponds for fish.

While there’s a spectrum of what is practical and what the public has a will for, Gill says discussions about de-extinction and rewilding are great to highlight why species matter and their roles.

Gill says she’s interested in a variety of topics — from the natural world to history — and that growing up in the ’80s and ’90s, she became acutely aware of the environmental problems facing the planet.

As a young girl, Gill says she loved learning and loved sharing what she knew with other people.

“Probably as a kid I was insufferable, but now I’m proud to do it,” she says.


Photo by Kit Hamley King penguins (Aptenodytes patagonicus), like other seabirds, are an important part of the marine-terrestrial nutrient linkage on the Falkland Islands. The penguins transport nutrients from the ocean to the land in their feces, enabling coastal plants to thrive in an otherwise nutrient-poor environment.


One of her moments of inspiration happened when she was an undergraduate at the College of the Atlantic. Guest lecturer Marcus Vandergoes, then a UMaine Climate Change Institute professor, was demonstrating how to use a coring device in Sunken Heath in Acadia National Park.

Gill describes the process as similar to sticking a straw in a milkshake and capping the top hole with your thumb. Rather than pulling up gooey chocolate ice cream, students pulled up 12,000-year-old light gray clay from the last Ice Age.

Gill says seeing time — reflected in changes in the sediment core — and touching the past were the coolest things that had ever happened to her. Something clicked.

Standing in Sunken Heath, a movie began playing in her mind of what the bog looked like thousands of years ago and how it got to be like it is now.

“I like thinking in big scales — big scales in time and big scales across space,” she says.

Imagine time fast-forwarding through a film. In the movie’s opening scene, ice 2 kilometers thick envelopes the landscape. Its massive weight compresses the Earth’s crust.

As the movie progresses, ice melts and the sea rushes in over land now called Maine. Without the massive weight of the ice, the Earth’s crust rebounds, causing the ocean to retreat. Eventually, grasses, mosses and willows grow, along with an occasional spruce tree.

Time passes and boreal forests grow — an attractive habitat for woolly mammoths, giant beaver the size of black bears, woodland caribou, dire wolves, musk oxen, giant moose and elk, grizzlies and short-faced bears.

After a brief return to Ice Age conditions, the current warming period begins. Humans appear for the first time, and the largest animals disappear.

For decades, scientists have researched why some megafauna — giant charismatic animals like mammoths — went extinct. Gill, though, prefers to study what happened to the land and other animals after the extinction.

“If we want to understand how plants respond to extinction of animals, we need to be able to directly compare those two fossil records,” she says.

This is tricky, because fossil bones aren’t usually found in sediment cores. So Gill gets creative, looking for the disappearance of spores from a fungus that reproduces on animal dung to time the local extinction of mammoths.

“The idea is we can look to the fossil record to understand how species responded to climate change and will respond going forward to inform conservation,” she says.

In her research, Gill found the extinction of mammoths and other large plant-eaters triggered a 1,000-year period of upheaval and ecological surprises that was quite unlike anything seen since.


Photo by Kit Hamley Long-tailed meadowlarks (Sturnella loyca falklandica), seen here atop marram grass (Ammophilia arenaria), are only found in the Falklands Islands. Long-tailed meadowlarks survive by feeding mainly on insects, like the one caught in this photo.


Today’s plants are all Ice Age survivors, but their ecology is different in the absence of those animals. And this has big important conservation relevance, she says.

Gill has traveled the country and world doing research. Her lab concentrates on understanding consequences of climate change and extinction on ecosystems, particularly interactions across the food web.

She shares with land managers how ecosystems are interconnected and what happens when one piece out of the puzzle is removed.

Currently, Gill and UMaine students Dulcinea Groff and Kit Hamley are studying interactions of penguins, tussock grass and sheep on the Falkland Islands, an archipelago of two main islands and nearly 800 smaller islands.

The UMaine team is striving to find ways for all the islands’ inhabitants — residents, sheep, sheep ranchers, sea lions, tussock grass, penguins and other seabirds — to exist in healthy harmony despite competing interests, as well as sea-level rise and erosion.

Part of the research is examining the fossil record to learn how sensitive the ecosystem has been in the past.

The native tussock grass, which can grow over 6 feet high in the windy, cold climate, provides habitat and protection for penguins and seals. In turn, penguin and sea lion feces nourish the grasses. The sheep, brought to the islands in the 1800s, eat the tussock grass, which impacts the habitat for sea lions and penguins.

Rotational sheep grazing 05 be one resolution, Gill says.


Photo by Kit Hamley Sheep farming and the export of wool have been the economic base for 140 years in the Falkland Islands, where acidic and infertile soil make it difficult to grow crops. Roaming sheep interact with native grazing upland geese (Chloephaga picta leucoptera), as well as penguins and other seabirds.


Gill strongly believes in communicating science so it’s understandable and relevant to a variety of audiences— from 5-year-olds to senators.

In addition to sharing her expertise with students, Gill writes a blog, “The Contemplative Mammoth: (ecology and climate change from the 4th dimension).” Topics range from the causes of ice ages to public education.

In her 09 . 16 blog, “In defense of information by, of, and for the people,” Gill wrote: “I dedicated my dissertation to the forgotten, unnamed women who wrote the manuscripts, conducted the experiments, and brewed the coffee and cared for the babies so that their husbands and colleagues could win Pulitzers.

“I wouldn’t be here without those women. And I wouldn’t be here without libraries, Sesame Street, free school breakfasts, the Pell Grant, or the National Science Foundation, either.”

She frequently tweets as well (@JacquelynGill) and says social media has been a great way to connect with scientists, the public and journalists.

Gill began blogging in college because she thought she had a voice to contribute.

Others agree.

“I think climate change is really going to force us to be creative with conservation solutions. This 05 be the kind of creative solution we need to think beyond the level of the species and protect biodiversity as a whole.”
Jacquelyn Gill

She has been a source for articles in National Geographic and Rolling Stone, and appeared in last summer’s five-part PBS series “First Peoples” about the spread of the first humans across the globe.

In the Rolling Stone article “The Point of No Return: Climate Change Nightmares Are Already Here,” Gill said ancient data provide “really compelling evidence that there can be events of abrupt climate change that can happen well within human life spans. We’re talking less than a decade.”

Gill says there is still time to turn things around, but to do that, greenhouse gas emissions need to be severely curbed on a massive scale.

“In terms of acidification of oceans and sea-level rise, there are points of no return,” she says. “The sooner that we act, the more likely it will be that we avoid a catastrophic increase in temperature in the future. It comes down to political will.”

Because de-extinction, rewilding and other conservation strategies can’t remedy an uninhabitable planet.

Exploring Extinction Video – J. Gill

Shifting Extinction Video – J. Gill, K. Hamley, D. Groff

Martin Sizes up Shrinking Bison Video – J. Martin