Book Review: Crossings - How Road Ecology is Shaping the Future of the Planet

By: Haley Yarborough

Book Review: How Road Ecology is Shaping the Future of the Planet

Written By: Ben Goldfarb

Why did the chicken cross the road? Ben Goldfarb revisits this age-old joke in his 2023 book Crossings: How Road Ecology is Shaping the Future of the Planet. Hidden within the question is a “chestnut” of assumptions—ones that shape the vast and ever-expanding network of roads fragmenting lands across the United States and beyond. Roads have become so ubiquitous that we rarely question their presence; instead, we view the chicken’s behavior as the mystery. Goldfarb explains: “The road is a given; it’s the fowls whose actions demand an explanation” (p. 10).

He frames this question in a way that makes readers uncomfortable, challenging the idea that we can care deeply about wildlife without considering the implications of piloting a “three-thousand-pound death machine” down a stretch of highway. This is what Goldfarb does so effectively in Crossings: he forces you to confront the ecological and social costs embedded within infrastructure we’ve come to accept as natural—costs that extend beyond just roadkill.

We are in the midst of what Goldfarb describes as an “infrastructure tsunami”—an era in which roughly 40 million miles of roads span the earth’s surface, including about 4 million miles in the United States, which has the largest road network in the world. Over the past century, road ecologists have gathered extensive data on the impacts of these road systems on wildlife migration, behavior, movement patterns, and soundscapes.

Animals are losing their ability to migrate for food and mates, traffic chases swaths of birds away from their habitats, and invasive plants hitch rides on tire treads. Beyond environmental damage, roads also perpetuate injustices by disproportionately burdening low-income communities and communities of color with pollution, noise, and neighborhood displacement. As Goldfarb puts it, “roads had also severed reciprocal human relationships,” not just animal ones (p. 204). Crossings put many of these complex effects into perspective, offering readers a glimpse into the complicated, depressing, and fascinating ecological world roads create for humans, plants, and wildlife.

Goldfarb describes his visit to a tunnel under U.S. Highway 93 in western Montana on the Flathead Reservation. These crossings were built to allow animals like bears, deer, and frogs to safely pass beneath the road — reducing wildlife-vehicle collisions and reconnecting fragmented habitats. But what’s especially interesting is that the structures themselves have become novel ecosystems. The road’s medians and verges have become habitats where animals can forage, while plants reclaim disturbed soil, illustrating how infrastructure reshapes ecological communities even at its margins.

Roads also shape more than landscapes for the living. Goldfarb takes readers through the world of “necrobiomes,” an ecosystem centered around animal carcasses and decay. Roads generate unique food webs, particularly for animals like coyotes, ravens, and vultures, who often rely on roadkill for food. Wildlife have learned to patrol roads looking for carrion, sometimes clever enough to adapt their behavior to the rhythms of traffic. These kinds of novel ecosystems carry both the benefits and risks of dynamic ecological zones. On one hand, scavengers play an important role in cleaning up roadkill, recycling nutrients, and preventing disease spread. Conversely, they become more vulnerable to becoming roadkill themselves, creating a dangerous feedback loop. Goldfarb also offers an interesting perspective to reduce waste caused by humans, creating what he refers to as “American Roadkill Cuisine.”

“Our predilection for scavenging changed us forever. It forced us to grow; once we were competing with big cats, it behooved us to be big ourselves” (p. 192)

Goldfarb expands his reach from the world of necrobiomes, balancing the heavy weight of environmental devastation with his jovial and wry narrative skills. In a New England town, Goldfarb visits salamander tunnels constructed to protect the tiny amphibians during their spring migration. He paints an image of concerned citizens huddled in raincoats, ferrying slimy creatures across roads with spatulas and flashlights. The scene is both bleak and endearing, a tension Goldfarb leans into. The often incredible and heartfelt ways people protect wildlife are sprinkled throughout the book, from shutting down roads in Australia to allow millions of crabs to scuttle over and under highways to monkeys clambering on tightropes overpasses in India — a kind of “circus born out of necessity.”

While Goldfarb finds humor and hope in these sometime entertaining solutions to fragmentation, he offers a sobering and sympathetic glimpse into the human dimensions of infrastructure as well. Crossings does not just confront the ecological costs of roads; it reckons with the social and racial inequalities woven into the history of infrastructure. As Goldfarb travels through cities and reservations, he discusses how highway construction has often resulted in displacement and division, disproportionately burdening communities of color and Indigenous peoples with pollution, noise, and dangerous traffic. The author states that the effect of this is not just a relic of the past, but an ongoing reality that shapes the environment and livelihoods. As Goldfarb explains, “Just as road ecology pushes us to expand our view of how highways distort nature, we need to broaden our understanding of how they affect humans” (p. 287)

Goldfarb does not just present the problem, either 一 he explores the sometimes unconventional solutions. Expanding research could explore how principles of green infrastructure—such as wildlife corridors, permeable surfaces, and context-sensitive road design—can be systematically applied to both new developments and retrofitted urban spaces. Interdisciplinary studies combining ecology, urban planning, and environmental justice could further illuminate how to create transportation networks that are not only more sustainable, but more equitable.

Crossings ends by reflecting on the inevitably intertwined fates of humans and wildlife, reminding readers that every road we build reshapes the world for both. We are left with the quiet insistence that our infrastructure is not fixed, but living systems — ones that we have the power to reimagine with humility, care, and recognition that maybe our view of the natural world is wrong. That it’s not “why did the chicken cross the road?” But rather “why did the road cross the land?”

About the Reviewer

Haley Yarborough grew up in Bishop, California, and is a University of Montana Master of Science candidate for Environmental Studies. She has worked as a general reporter for the Seeley Swan Pathfinder, a reporter and arts and culture editor for the Montana Kaimin, and a student intern at the Flathead Lake Biological Station. Haley has a strong background in environmental studies, journalism, and biology, and graduated with degrees in both Journalism and Biology in May 2024. Her interests include environmental storytelling, road ecology, wildlife conservation, and the intersection of infrastructure and ecological justice.