Human movement today is about 40 times greater than the combined movement of all wild animal species – including land mammals, birds, and arthropods. A new study quantifies that shift and shows how it rose over the last two centuries.
The work centers on the Weizmann Institute of Science in Israel and asks a blunt question. How much motion do people add to the planet compared with animals that still roam free.
Walking exceeds animal movement
The team defined biomass movement (the total mass of a group multiplied by the distance it travels in a year) to compare humans and animals on the same scale. That single yardstick connects walkers, cars, flocks, herds, and ocean life without mixing apples and oranges.
The work was led by Dr. Yuval Rosenberg at the Weizmann Institute of…
Human movement today is about 40 times greater than the combined movement of all wild animal species – including land mammals, birds, and arthropods. A new study quantifies that shift and shows how it rose over the last two centuries.
The work centers on the Weizmann Institute of Science in Israel and asks a blunt question. How much motion do people add to the planet compared with animals that still roam free.
Walking exceeds animal movement
The team defined biomass movement (the total mass of a group multiplied by the distance it travels in a year) to compare humans and animals on the same scale. That single yardstick connects walkers, cars, flocks, herds, and ocean life without mixing apples and oranges.
The work was led by Dr. Yuval Rosenberg at the Weizmann Institute of Science (WIS). His research focuses on global ecology and quantitative estimates that place humanity in context.
Humans now account for far more motion than land wildlife because there are billions of us and we travel daily. On average, each person covers about 19 miles per day by foot, bike, road, rail, or air.
About 65 percent of human biomass movement happens in cars or motorbikes, 10 percent in airplanes, 5 percent on trains, and 20 percent on foot or bicycles.
Even walking alone now exceeds the combined movement of wild land mammals, birds, and arthropods by roughly six to one.
A shift two centuries in the making
A companion analysis reconstructs mammal biomass since 1850 and shows a sharp pivot. Wild mammal biomass fell about 70 percent, while human biomass rose about 700 percent and domesticated mammals increased about 400 percent.
Those numbers reflect both population growth and the spread of motorized travel. They also capture how domesticated species displaced wildlife in both mass and motion.
The modern period is often called the Anthropocene, the time when human activity shapes most planetary systems. It is a useful lens here because it links mobility, energy use, land change, and wildlife decline.
Why animal movement matters
Animal movement spreads nutrients, seeds, energy, and genes across landscapes. When that flow weakens, ecosystems lose the quiet services that keep them stable and productive.
Human activity alters how animals move, how far they go, and when they travel. A global assessment shows widespread disruption of animal movement across birds, mammals, reptiles, amphibians, fish, and arthropods.
Reduced movement can lower survival, shrink ranges, and isolate populations. It also weakens natural processes that keep soils, rivers, and food webs functioning.
Most living movement happens in the sea, not on land. Every night, vast layers of small fish and zooplankton rise toward the surface, then sink by day.
This daily pulse is called diel vertical migration, a daily up and down swim to feed and hide. It moves enormous mass through the water column and rivals the scale of human walking.
Marine animal movement has declined since the 1800s as industrial fishing and whaling removed large, far-ranging species. The contraction is sharpest for big animals that travel long distances and link distant habitats.
Energy costs and the weight of machines
Movement takes energy, and for many mammals the cost per pound per mile is modest. Humans on foot are efficient movers, but the machines we ride are heavy and energy hungry.
Counting only the passenger’s mass makes motor travel look efficient, yet the vehicle mass and fuel make the true energy bill high. That energy bill scales up across billions of trips and adds to the overall pressure on ecosystems.
“We often marvel at the power of nature compared to how small we are,” said Ron Milo, a professor at the Weizmann Institute. His point is simple, the everyday movement of people can now overshadow iconic migrations.
The numbers offer a way to compare that is concrete and testable. They also help track progress if policies or technologies change travel patterns.
Boosting animal movement
If walking already beats the movement of all land wildlife, then road, air, and rail are the levers that matter most. Small shifts in average miles per person can change the totals a great deal because the baseline is so large.
Protecting and reconnecting habitats can boost animal movement without forcing wildlife into risky crossings.
Tracking these flows with shared, open data will show whether interventions work or fall short.
The study is published in the journal Nature Ecology & Evolution.
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