<p>Wolf spiders are top predators in the tundra. Their activity has cascading effects on belowground food webs, decomposition rates, and soil nutrients, but these effects are different under warmer-than-usual temperatures.</p> <div><span itemprop="caption" style="box-sizing: border-box; font-family: GeoEditRegular, &quot;Franklin Gothic Medium&quot;, &quot;Franklin Gothic&quot;, &quot;ITC Franklin Gothic&quot;, Helvetica, Arial, sans-serif; font-size: 14px; letter-spacing: 0.1px; background-color: rgb(255, 255, 255);">&nbsp;</span></div>

Wolf spiders are top predators in the tundra. Their activity has cascading effects on belowground food webs, decomposition rates, and soil nutrients, but these effects are different under warmer-than-usual temperatures.

 
Photograph by Kiki Contreras

Climate Change Makes Spiders Bigger—And That’s a Good Thing

High temperatures make arctic wolf spiders ditch their favorite food, indirectly helping the environment.

The Arctic tundra is teeming with predators, just not the ones you might expect: By biomass, arctic wolf spiders outweigh arctic wolves by at least 80-to-1.

The eye-popping calculation, published today in PNAS by National Geographic explorer Amanda Koltz, could shape our understanding of how the Arctic will respond to future climate change.

Her study reveals that at increased temperatures and population densities, arctic wolf spiders change their eating habits, starting an ecosystem-wide cascade that could change how quickly melting permafrost decomposes.

Human activity, especially the release of heat-trapping greenhouse gases, is warming the planet—and the Arctic is getting hotter twice as fast as the rest of Earth.

The Arctic's heat-up is particularly worrisome because as the region warms, permafrost—a frozen

Unlock this story for free
Create an account to read the full story and get unlimited access to hundreds of Nat Geo articles.

Unlock this story for free

Want the full story? Sign up to keep reading and unlock hundreds of Nat Geo articles for free.
Already have an account?
SIGN IN

Read This Next

What bacteria lurk in your city? Consult the bees.
Is melatonin giving you nightmares?
Why are these orcas killing sharks and removing their livers?

Go Further

Subscriber Exclusive Content

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet