Angry spiders, Animal Minds, and a Slime Mold called Harry

(This was originally posted last summer)

Have you ever been glared at by a spider?

Usually, they scurry away as fast as their eight little legs can go, but this one stood her ground, pulling herself up tall with body held stiffly, head cocked to the side and a look on her face of pure indignation. She was furious.



Okay, maybe I’m projecting a little. How does anyone know what goes on in animal minds, let alone an arthropod, a simple creature with a brain the size of a…well, let’s just say, really, really small. There can’t be much going on in there, right?

But the vibes coming off this spider told me different. I just knew she was mad, and a little devastated, too. I was stealing her dinner.

I didn’t mean to do it. Normally, I would never get between a predator and its prey—it’s bad form. It goes against the natural order. But when I saw the giant crane fly struggling in the corner of my studio, I thought it had simply gotten tangled in a bit of cobweb. Why should an innocent creature suffer death just because of my lousy housekeeping?












Crane flies are like the supermodels of the fly family, with long, delicate legs, intricately designed wings, and big globe-shaped eyes. So there I was, down on my knees, scissors in hand, working like a surgeon to extract the fragile creature, when suddenly I got the feeling I was being watched. A few inches away, a long-legged pholcid spider stood, body language shouting, “how dare you!”

Hmmm, what to do? The spider had won the fly fair and square—who was I to interfere? But the crane fly was looking at me with those beautiful eyes…she obviously wasn’t looking forward to having her innards sucked out.

In the end, I freed the fly and released her to the garden, but I felt a little uneasy about favoring one species over another. Plus, now I was going to have to share my studio with an angry spider.



Projecting human emotions onto animal behavior, or anthropomorphism, has been a tricky issue for scientists who study animals for hundreds of years. It can interfere with scientific method—clouding judgment and obscuring truth. Be objective—that was Rule One for a long time. And a scientist that gets too close to her research subjects—who develops a relationship with them—may be coloring her results by sending unconscious signals that the animal responds to. At one point Jane Goodall, the famous primatologist, was even criticized for giving the chimpanzees she studied human-sounding names rather than numbers.

But, it seems to me the more science reveals about other species, the more we learn they are a lot smarter and more complex, you might even say, more human, than we ever knew.



Slime mold, scientifically known as myxomycetes, is one of the most peculiar life-forms on earth. It is essentially an amoeba-like mass of protoplasm, with no brain, no nervous system, no eyes or ears or legs. It is common in forests and other moist environments, and is very unusual in that unlike plants, it actually moves, sending out tendrils of its slimy self over the forest floor, creeping slowly along as it hunts for food. Like a fungus, when it is ready to reproduce, it sends up fruiting bodies that release spores.


I found this gorgeous slime mold in an old-growth forest in Oregon, near Mt. Hood. The tendrils of slime along the edges are like its “feet”, enabling it to move through the forest. The bright yellow part is the fruiting body, similar to a mushroom.


Amazingly, it can also solve maze puzzles that would be tricky even for humans to solve! Scientists have concluded that slime mold can ‘compute’ even though it doesn’t have a single brain cell. Does this mean you don’t need a brain to be smart? (insert joke about your least favorite politician here).

I am an interpreter, not a scientist. I try to draw connections between nature and personal experience as a way of appreciating the beauty and diversity of life on this planet—between what’s out there in the wild and what’s inside of you and me. Sometimes, this involves a little anthropomorphism.

But while I’m walking around with my head in the clouds, arguing with spiders and contemplating slime, somewhere in a laboratory a white-coated scientist labors through the hard work of gathering data, making conclusions, proving and disproving, all the while resisting the urge to get friendly with a blob of slime. It’s the natural order.



For more cool stuff:

Awesome videos of slime mold:

In case you’re skeptical about the slime-mold-maze-thing: