Use your ganglia

Dear Dr. Universe, Do bugs have hearts and brains?
-Nick

Dear Nick,

Take a look inside a bug and you’ll find a brain in its head and other little brains called “ganglia” along its whole body. These tiny control centers help insects see, taste, and smell.

They also help them quickly escape threats, like other bugs.

“If you had little brains everywhere else, you would also be much quicker,” said professor Laura Lavine. Her office at Washington State University is full of insects, including ones you can eat.

Many insect brains are smaller than the period at the end of this sentence. Even though they’re small, having several brains allows insects to make decisions much faster than if they had only one. Insects can also live without their head for a few days, skittering around with just the little brains along their backs.

Some bees can remember shapes or help sniff out bombs using their brains, said Lavine. Jumping spiders have vision as strong as humans, so some scientists use the spider’s sight control center to learn about people’s eyes.

As the brain receives messages, an insect’s heart is pumping blood. Usually the blood is green and it flows through a tiny tube that runs along the insect’s body. It’s actually located pretty close to the brains. Insect blood can be toxic. Sometimes they will let a little blood ooze out of themselves when they think they are in trouble

“It warns the attacker that they are dangerous,” Lavine said. “Then they escape.”

She explained how insects are in a family called arthropods. Arthropods wear their skeletons on the outside of their bodies and include insects, crabs, scorpions, and spiders. They all have hearts and brains wired in similar ways.

Right now, your heart is pumping red blood and sending oxygen to your body. Interestingly, if you covered an insect’s mouth it would still be able to breathe. That’s because insects breathe through hundreds of little holes in their bodies.

But they still need hearts. Just like other creatures, the heart pumps the blood that sends nutrients to the muscles and brain. It also keeps organs and tissues healthy, so insects can stay strong.

Before leaving Lavine’s office with an answer to your question, she offered me a toasted cricket. Insects are a good source of protein so many people around the world use them in their cooking, too. At first I wasn’t so sure about it, but it was actually pretty tasty, hearts, brains, and all.

Sincerely,
Dr. Universe