Could Extinct Species Save Today’s Forests? Scientist Makes the Case for Darwin Day

Darwin Dayat The State University of New York at Stony Brook serves as a reminder that "evolutionary thinking is the bedrock of our understanding of the living world."

This year, the Department of Ecology and Evolutionhosted a conversation that pushed the boundaries of traditional lecture, moving from the preservation of what remains to the bold restoration of what has been lost.

Ben Novak, lead scientist from the non-profit Revive & Restore, joined the campus community to discuss the effort to bring back the passenger pigeon. Far from a mere "resurrection" project, Novak described the work as a form of restoration ecology, using the past to inform more resilient ecosystems in the present.

"We're trying to work with the dynamics of what would make better ecosystems in the present. We're just using the past to inform it because the last 500 million years of life on this planet is the literal natural experiment of every variation you could test in nature," Novak said. He added that using a tool like gene editing is "doing a job that is a million years old"

The event was co-sponsored by the Department of Ecology and Evolution and Stony Brook's Collaborative for the Earth(C4E), with financial support from the Provost's Office. C4E is focused this year on fostering conversations about a range of issues where climate change might require extreme (and often controversial) responses, making de-extinction a natural focus for the annual Darwin Day lecture.

For Joshua Rest, chair of the Department of Ecology and Evolution, hosting these conversations is a vital role for a research university. "It is a chance to practice how science works in real time by asking big questions, weighing evidence, and debating implications with care," Rest said.

"Hosting Ben Novak creates space for the kind of careful, public conversation a research university should lead, including bold and unconventional conservation ideas like passenger pigeon de-extinction and what it could mean to restore a species," he added.

The passenger pigeon was once the most abundant bird on the planet, with flocks numbering in the billions that could "obscure the noon day" like an eclipse, Novak explained. However, their importance was in their role as ecosystem engineers.

According to Novak, the passenger pigeon helped reset thousands of forest acres for at least 200,000 years. Because they were "hypersocial," millions of birds would roost in the same patch of forest, their collective weight breaking branches and even trees up to two feet in diameter. This disturbance, followed by a massive deposition of nitrogen-rich guano - sometimes inches thick - cleared the undergrowth and created a diverse mosaic of habitats.

Today, while the Eastern United States has more forest cover than it did 150 years ago, these forests are almost exclusively "closed canopy." Without the natural disturbances once provided by the pigeons, ecosystems that thrive on disturbances are disappearing, causing species like the Eastern cottontail to decline toward local extinction.

The path to de-extinction does not involve cloning in the way many imagine. Because birds cannot be cloned using traditional methods, researchers are turning to gene editing. The process begins by sequencing the genome of passenger pigeons from museum specimens and comparing them to a close living relative, the Band-tailed pigeon. Scientists at institutions like Rockefeller University and NYU Langone Health are working to identify the specific genes that would assist in editing for the passenger pigeon's unique social behaviors and physical traits.

Using CRISPR technology, these traits are "copied and pasted" into the germ cells of a living pigeon. When these edited birds breed, they act as surrogates to produce offspring that look, act, and function like the extinct passenger pigeon. Novak estimates that this effort could be achieved between 2027 and 2032.

While the passenger pigeon drives media headlines, Novak emphasized that de-extinction is only a small part of biotechnologies that provide a "genetic rescue toolkit" for living species in crisis. This includes biobanking cell lines for more than 200 endangered species, developing probiotic treatments for corals facing climate stress, and managing genetic diversity in fragmented populations, such as the black-footed ferret.

"Conservation has not adopted biotechnologies in the way that other industries were 14 years ago," Novak noted, suggesting that these tools are essential to combat the accelerating pace of plant and animal extinction caused by the "unintended consequences" of the growth of human populations and human-created climate change.

Novak concluded his talk with a philosophical reflection on Charles Darwin. While Darwin could not have imagined DNA or CRISPR, his theory of natural selection provided the "organizing scaffold" for the very technologies now being used to undo the damage of the last century.

"We've crippled the future," Novak said, referring to the millions of years it typically takes for nature to recover from mass extinctions. "With biotechnologies in the mix, we can create a bio-abundant, biodiverse future built on the intended consequences that we want to share."