Popular Science - USA (2020 - Winter)

big animal

brains are

overrated

why can’t i forget

how to ride a bike?

WHEN WE THINK, each of our brain cells fires signals

to as many as 1,000 neighboring neurons up to 200 times

per second. This enables complex decision-making like nav-

igating a four-way stop or solving an algebra problem. But

animals with tiny noggins (or none at all) also complete in-

volved tasks—no cerebral fireworks needed.

Ant brains are hundreds of thousands of times smaller than

ours, rendering them incapable of any significant individual

computing power. Instead, they employ an intricate hive mind

communication system, says New Jersey Institute of Tech-

nology entomologist Simon Garnier. The bugs emit chemicals

called pheromones when they encounter a resource, such as

food or a nesting site. Hundreds of fellow ants follow the smell,

leading to an organized army of satiated critters or the con-

struction of a giant (relatively speaking) anthill.

Even brainless, single-celled organisms called plasmodial

slime molds can comprehend simple lessons, says Audrey

Dussutour, a biologist at the University of Toulouse. She

taught these blobs to transverse salty patches of land by grad-

ually filling them with sodium. The more salt they contained,

the sooner they “realized” they could cross safely, proving an

elaborate neural network isn’t the only key to success.

LEARNING TO PEDAL IS NO EASY FEAT.

But forgetting is harder. For most people, even af-

ter decades-long hiatuses, cruising still feels like a

breeze. The key is how the brain remembers the task.

Mastering cycling requires a ton of higher-level

thinking: Your noggin’s motor cortices plan and exe-

cute precise muscle control, the cerebellum helps you

balance and time your pedal strokes, and the basal

ganglia keep these movements fluid rather than jerky.

It’s precisely this colossal load of cerebral coor-

dination that ensures the skill sticks around, says

Jürgen Konczak, a neuroscientist and biomechanics

expert at the University of Minnesota. We use every

muscle movement and subsequent brain connection

involved in bike riding during other activities, like

dancing, playing sports, and walking—just not all at

the same time. When the time comes to hop back on

the saddle, all the necessary moving parts are already

tuned and oiled. There’s never a bad time to start ped-

aling again. It’s truly a skill that lasts a lifetime.

BYCANDICE WA N G

BY HANNAH SEO

GLENN ORZEPOWSKI (ANTS)

POPSCI.COM / WINTER 2020 127