Saturday, June 26, 2021

Animal intelligence 101: Which ones are top of their class?

bees on honeycomb

When the topic of animal intelligence comes up, we might argue whether a crow or a parrot is the cleverer, or if dolphins are smarter than manatees. Seldom do we ascribe smarts to life-forms such as insects, plants or fungi. And it is rare indeed that we question our intellectual primacy among animals. It is true that no other species can point to monumental achievements such as the Coliseum, acid rain, nerve gas and atomic weapons. But that does not mean other species are bird-brained. Metaphorically speaking.

It makes sense that elephants and whales are whiz-kids, given the size of their heads. Depending on species, whale brains weigh between twelve and eighteen pounds. Dumbo’s cranium would tip the scale at around eleven pounds, which probably explains why elephants never forget. Compared to them, our three-pound brains are small potatoes. What sets mammal brains apart from other classes of animal is the neocortex, the outermost region of the brain responsible for higher functions such as language and abstract thinking.

But size is not the only thing that counts. Our neocortices, unlike those of most animals, are highly convoluted. This means we make everything way more complicated than necessary. That is probably true, but actually, convolution gives our brains a lot more real estate by volume. A lot of acreage can fit in a small space if it is nothing but valleys and mountains. Imagine if Texas was a rug and it got scrunched up to the size of Vermont. This greater surface area equates to more processing power than a less highly folded brain like a whale’s.

The ability to make and use tools, and to carry them for future use, is one of the widely accepted indicators of intelligence. In the past, it was thought that only humans and our close ape relatives used tools. Some gorillas use sticks to spear catfish, and in at least one case, a gorilla was seen using a log to fashion a bridge to cross a stream. I suppose if they started charging a toll, we would give them more respect.

Only just recently has the intelligence of cephalopods like cuttlefish, squid and octopodes (octopuses; whatever) been documented. The latter have been observed foraging for discarded coconut shells and using them to build sea-castles of sorts in which to hide. If their ability with tools progresses, I bet they could knit an awesome sweater in no time.

Birds also use tools – crows, for example, will use a stick to poke at bugs they can’t otherwise reach. When an insect bites the stick, the crow pulls the stick out and eats the bug. Humans always assumed birds were not very smart because their brains are the weight of a paper clip, and range from pea-size to maybe the size of a walnut. Well, we’ve had to eat crow, because bird brains are far more neuron-dense than mammal brains. It’s like we were comparing the microchip brain of birds to the big vacuum-tube human brain and sneering, when in fact many birds test on par with primates for intelligence.

We know that honeybees use a sort of interpretive bee-dance to communicate with each other as to the location of flowers and picnickers. Our native bumblebees seem to have one up on them. In 2016, researchers at Queen Mary University of London, England found that bumblebees learned within minutes how to roll a tiny ball into a little hole to get a sugar-water reward. I assume the researchers are now busy with bumblebee golf tournaments.

Even vegetables can learn new tricks. Experiments have shown Pavlovian responses when light and other, unrelated stimuli are presented together from various angles. Plants of course will grow in the direction of light. But when the light was switched off, the plants tilted toward the other stimuli, just like the way Pavlov’s dogs salivated when they heard bells. (I imagine the winter holiday season was frustrating for those drool-pooches.)

Humans, apes, squids, birds, bugs, and plants – there’s nowhere to go but down. Enter the plasmodial slime mold, a slow-moving single-cell organism able to scout the landscape, find the best food, and engulf it, growing ever larger. Coming soon to a theater near you.

It sounds like a sci-fi film, and a blob of pink, yellow or white slime mold, possibly up to a square yard in area, does look pretty alien. They usually live in shaded forest environments, but can show up on your flower bed, and a friend once sent a picture of a slime mold which had engulfed an empty beer can he left out overnight.

Researchers discovered that a plasmodial slime mold uses complex algorithms to make decisions – logical ones, it turns out – regarding which direction to proceed as it slimes across the landscape. One of the lead researchers in the 2015 study is Simon Garnier, an Assistant Professor of Biology at New Jersey Institute of Technology. He said that “[studying slime molds] challenges our preconceived notions of the minimum biological hardware required for sophisticated behaviour.”

And in a story that sounds right out of the satirical website The Onion, in 2017 the Amherst, Massachusetts-based Hampshire College named a slime-mold species to its faculty as “plasmodial scholars-in-residence.” Another true story. In an announcement on the college’s website, Hampshire biology professor Megan Dobro explained that “Slime molds have navigated complex ecosystems…for a billion years, proving themselves to be some of the foremost optimizers on the planet.” Algorithms used by slime molds will be studied for applications to difficult human problems.

I think we should pay better attention to our non-human relatives. Chances are they have a lot more to teach us.

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Paul Hetzler

Paul Hetzler has been an ISA Certified Arborist since 1996. His work has appeared in the medical journal The Lancet, as well as Highlights for Children Magazine.

You can read more of his work at PaulHetzlerNature.org or by picking up a copy of his book Shady Characters: Plant Vampires, Caterpillar Soup, Leprechaun Trees and Other Hilarities of the Natural World




10 Responses

  1. Boreasfisher says:

    Paul, as you may know, Princeton biologist John Bonner wrote a lovely little book on slime molds many years ago. And they just keep getting smarter, maybe we should give them the vote.

  2. Boreas says:

    If one considers the brain power of a bird, then considers that birds are essentially dinosaurs that survived the die-off, consider the potential brain power of a T-rex. We have always considered dinosaurs stupid because of their relatively small brains, but they kept mammals at bay and essentially ruled the world for many millions of years.

    There is a lot more to plants than we give them credit for as well. They have been around longer than any terrestrial animal. What plants learned and took advantage of early on is cooperation is preferable to competition. Early on, plants began to “see” the opportunities that sharing nutrients and resources with fungi and other forest life benefitted ALL over the long run. This destroys the fallacy that a forest is nothing more than a collection of trees. Plants even “learned” to incorporate mobile organisms to spread their seeds – in essence, allowing the forest to move slowly over millennia. Research has also found over the last few decades that plants communicate chemically – even alerting others to danger.

    So, we who consider ourselves superior in intelligence compared to other species, may need to take a keen look at the true meaning of intelligence – and give credit where credit is due.

  3. Randy Fredlund says:

    I believe we can determine the intelligence of slime mold on the basis of which brand of beer is preferred.

  4. Rob Bick says:

    Don’t forget our politicians, on both sides of the aisle, who seem to have mastered these complex slime-mold algorithms and managed to stuff them into tailored suits.

  5. Maggie Jihan says:

    Oh dear… don’t tell the vegans! Whatever will they eat if they discover that plants have sentience and intelligence, same as the cute fluffy animals with faces that resemble our own? On 2nd thought, PLEASE tell the vegans. As a forest-lover and gardener of several decades, I’ve tried to tell them for years that consciousness is not restricted to the cute/fluffies with faces (and brain/nervous systems) resembling our own–and that all living things want to go on living. Even that carrot you’re eating instead of a steak. 😀

    But seriously. I love this stuff. Been observing it for years in all manner of life-forms, great to see scientists proving it.

  6. Boreasfisher says:

    The great ranch Canadian poet Louis Dudek who taught at McGill for many years used to write poems to his plants. Must confess that I thought he was nuts…turns out he was just advancing literary modernism.

  7. Charlie Stehlin says:

    “dinosaurs …… essentially ruled the world for many millions of years.”

    >We don’t truly know this Boreas! I’d like to keep an open mind and think some sort of intelligent being lived amongst them at one time. How can we know for sure. There are so many unanswered questions.

    “So, we who consider ourselves superior in intelligence compared to other species, may need to take a keen look at the true meaning of intelligence – and give credit where credit is due.”

    > Yes sir Boreas. If you ask me we’re still coming out of the cave generally speaking, the large lot of us, especially those in positions of power who think they know what’s best for the rest of us.

    • Boreas says:

      “dinosaurs …… essentially ruled the world for many millions of years.”

      >We don’t truly know this Boreas! I’d like to keep an open mind and think some sort of intelligent being lived amongst them at one time. How can we know for sure. There are so many unanswered questions.

      True Charlie. Unfortunately saddles, bridles, and stirrups made of reptile leather do not fossilize well!

  8. Charlie Stehlin says:

    “consciousness is not restricted to the cute/fluffies with faces (and brain/nervous systems) resembling our own–and that all living things want to go on living….”

    > There are signs of intelligence in all living things in other words. All life matters Maggie! Especially so considering the truism you say above. It’s too bad we don’t have those in positions of power who are so enlightened. Sadly I say!

  9. Maggie Jihan says:

    Charlie Stehlin, yes, so very sadly for all of Life.

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