The Science of Why, Volume 5: Answers to Questions About the Ordinary, the Odd, and the Outlandish

By Jay Ingram

Chock-full of peculiar puzzles, mind-bending mythbusters, and quirky questions, the fifth pop science book in the bestselling Science of Why series is perfect for anyone curious about the weird and wondrous world we live in.

Have you ever wondered if octopuses are from outer space? What Mexican jumping beans are? Or if banana peels are really slippery?

If questions like these are keeping you up at night, you can rest easy. Bestselling author Jay Ingram is here to answer all the whimsical and whacky wonderings that have baffled people since the dawn of time. From our bodies to our pets (and other beasts) to the natural world around us, Jay tackles science topics big and small, such as:

Did dinosaurs sit on their eggs?
What is our funny bone?
Is there a specific muscle that makes dogs cute?

Because who hasn’t pondered whether plants have feelings? Or if Robin Hood was a real person? Or what humans will look like in the future?

Teeming with amusing answers to bemusing questions—and handy and hilarious illustrations—this latest volume separates fact from fiction, lesson from legend, and myth from marvel. Endlessly illuminating and entertaining, The Science of Why, Volume 5 is five times the fun for new and old readers of the series.

• Language: English
• Publisher: Simon & Schuster
• Release date: Nov 10, 2020
• ISBN: 9781982140861

Jay Ingram

JAY INGRAM was the host of Discovery Channel Canada’s Daily Planet from the first episode until June 2011. Prior to joining Discovery, Ingram hosted CBC Radio’s national science show Quirks & Quarks. He has received the Sandford Fleming Award from the Royal Canadian Institute, the Royal Society’s McNeil Medal for the Public Awareness of Science and the Michael Smith Award from the Natural Sciences and Engineering Research Council. He is a distinguished alumnus of the University of Alberta, has received five honorary doctorates and is a member of the Order of Canada. He has written twelve books, including Theatre of the Mind and Fatal Flaws.

Book preview

Part 1

Awesome Animals

Are octopuses from outer space?

IN 2018, THIRTY-THREE SCIENTISTS published an article in the journal Progress in Biophysics and Molecular Biology arguing that octopuses are actually alien life-forms that arrived on earth on a space rock 270 million years ago.

Yes, you read that correctly.

And, yes, it’s as crazy as it sounds. Octopuses are unique is so many ways that one scientist has said, It’s like meeting an intelligent alien—but he didn’t mean that literally.

This theory is an attempt to explain why the octopus is so different, especially genetically, from even close relatives like the chambered nautilus. But it’s not just about the genes: octopuses have a bit of an alien look. They’re also extremely smart, can change pattern and color to blend into their surroundings, and each of their eight arms has its own brain. That last fact alone puts the octopus in a class by itself.

Octopuses have a legendary ability to escape aquariums. They can use tools and solve problems, and they seem able to think in an almost humanlike way. One well-known experiment tested octopuses on their ability to open a complicated set of boxes to get at a crab treat inside. The first box had a latch that needed to be twisted open; inside that was another box, which slid to open; and that in turn was inside a third box, which had two different locks. Two or three trials was all octopuses needed to be able to open all the boxes in three or four minutes.

What makes an octopus so smart? Its nervous system has 500 million neurons, ranking it somewhere between the European rabbit and the western tree hyrax, an African guinea pig–like animal. But the number of neurons alone isn’t a good measure of intelligence. The way those neurons are organized is important, too, especially in the octopus.

Of the octopus’s 500 million neurons, 150 million are found in the brain, and the other 350 million are shared among the arms. In effect, each arm has its own minibrain and is capable of making its own decisions. If one of the suckers detects something delicious, for example, that arm will alert the other arms to what’s happening. Then the arm will curl around the food, making a kind of hand, while the rest shapes itself into an upper and lower arm and an elbow so that the hand can bring the food to the mouth.

Science Fact! Eerily, an arm that’s been separated from an octopus’s body will still grab food and try to pass it to where the mouth should have been. It will also try to crawl away on its own.

What sets octopuses apart? The chambered nautilus, a cousin, is not nearly as intelligent. Some experts think the key difference is that the nautilus never lost its shell. It leads a relatively safe and lengthy life (it can live up to twenty years), but perhaps not the most exciting one. The octopus, on the other hand, lost that shell completely as it evolved into its modern form. The argument is that losing the protection of the shell put evolutionary pressure on the octopus to become smart, agile, well camouflaged, and capable of squeezing into the tiniest spaces. The trade-off is that it typically survives only two or three years in the wild.

All of these features make the octopus an extraordinary creature, but the scientists arguing for its alien origin concentrate only on its genes. Genes build animals, but octopuses do it in a different way. They are genetically nimble and can apparently alter the way their genes are expressed, allowing them to respond rapidly to changes in their environment. But that nimbleness reduces the octopus’s ability to fine-tune its DNA over longer periods of time, the process that drives evolution. This machinery is not unique to octopuses—we humans have it, too—but in most other species, it’s a tiny feature of the genome, whereas in the octopus it is absolutely crucial.

That brings us back to the octopus as alien theory. The argument is that this ability to revamp the genome is not typical of other animals on Earth—therefore octopuses must have come from space. They would have arrived not as full-grown animals but as frozen octopus eggs. It would be pretty cool if it were true, but the evidence isn’t exactly airtight. It may look like the octopus appeared out of nowhere 270 million years ago, but there are so few octopus remnants in the fossil record that it’s impossible to be sure. And while their practice of gene editing is intriguing and unusual, does the fact that we do it, too, mean we come from space as well?

If you still want to believe that octopuses are aliens (and I wouldn’t blame you if you do!), you should know that for decades now the authors of this paper have been pushing the idea that life arrived on earth from space. All life, that is. So far they haven’t been able to persuade the rest of the scientific community of that.

Why are porcupine quills so hard to pull out?

YOU MIGHT HAVE SEEN one of those online images of an unfortunate dog with his muzzle full of porcupine quills. It wasn’t a great experience for the dog when those quills went in, but it was certainly much worse when they came out! From the porcupine’s point of view, though, the quills are one of the most advanced defense systems in the natural world.

Porcupines are the world’s third-largest rodent, after the beaver and the capybara. There are species scattered around the world, but the several subspecies in North America are unique for their barbed quills. Each quill is about 11 centimeters (4.3 inches) long, and the top 40 percent or so, the black part, is covered in barbs. One porcupine can have as many as thirty thousand quills on its body and tail!

If you’re thinking the barbs must make the quills really hard to pull out, you’re right: as you tug on a quill to remove it from your dog (or yourself!), the barbs, which are usually flat against the shaft, open up and spread out horizontally into the flesh, a little like an umbrella being opened. The harder you pull, the more they spread out, until eventually the quill is thicker and wider than the puncture hole it made in the first place.

But the barbs don’t just make the quills hard to remove—they also make them more able to penetrate the flesh of an animal. Quills have been found deep within other species’ muscles and in just about every organ: stomach wall, liver, lungs, and kidneys. It isn’t clear why the barbs aid penetration, but the experimental data are unambiguous. A team led by biomedical engineer Jeffrey Karp at MIT compared barbed porcupine quills with hypodermic needles, quills with the barbs sanded off, barbless quills from the African porcupine, and even artificial quills fashioned from polyurethane. Careful measurements of the penetration force needed for each of these showed conclusively that barbed quills pass through the flesh most easily—even better than a standard 18-gauge hypodermic needle. What’s more, the barbed quills cause less tissue damage going in.

Karp and his colleagues concluded that the relative lack of damage was related to how the stress of quill entering flesh is distributed. They argued that because that stress is concentrated around the barbs, a quill operates more like a serrated knife than a nail, entering with less force and making a cleaner cut. You can see it in photomicrographs: barbed quills cut much more smoothly than the barbless versions. Even artificial barbed quills made of polyurethane needed 35 percent less energy to penetrate muscle than artificial barbless quills. This doesn’t mean they don’t hurt, though. They really do.

Did You Know… Once a porcupine has embedded dozens of quills into the body of an attacker, how does it get away? After all, the quills are attached to the porcupine, too. It’s a serious issue because if enough quills are stuck in an enemy, the force required to pull away may be too much for the porcupine. But over time, a solution has evolved. When the porcupine smacks its target, the impact momentarily drives the quills back, breaking the links in which they’re seated. Then separation is easy. What’s extra cool about this is that the impact has to be powerful, like a porcupine lashing out with its tail. If the animal just lies down on a tree limb, that won’t be enough to dislodge the quills.

Dr. Karp and his teammates at MIT have biomimicry on their minds: they’re working on an improved hypodermic needle that would penetrate as easily as the barbed quill. They’ve already tested a prototype of a polyurethane needle with barbs, and it requires 80 percent less force than a barbless needle. Of course, a needle that goes in as easily as a porcupine quill can’t also be as hard to remove! Karp and his colleagues think the answer to that problem may lie in creating barbs that change shape once wet. But resistance to being pulled out could be an advantage, too: they’re also thinking beyond needles, to wound protection, to a patch to remain in place over tissues as they heal. In this case, both attributes of barbed quills would be important, especially the resistance to detachment, as long as it can be controlled.

In the meantime, there are plenty of biological questions to consider, like why does the North American porcupine have barbed quills while its African cousin doesn’t? It’s certainly not for lack of danger. The African porcupine’s main predators are lions, hyenas, and large birds of prey. So is there something different or more intense about the predatory pressure on our local porkies that pushed them to evolve barbed quills?

In some ways, the quills are more of a warning than a first line of defense, and the porcupine diligently advertises them by raising them in times of danger, creating an almost skunk-like white stripe down its back. It will also clatter its teeth together and release a pungent odor to announce it’s ready to use its quills. The odor has been described as the smell of goat or perhaps an exotic cheese. The one thing a porcupine doesn’t do is throw its quills. Naturalists have known this for 150 years, but the rumor still persists—perhaps because the quills release so easily when striking a target that they give the impression they flew through the air.

Unfortunately, sometimes all the brilliant engineering of barbed quills isn’t enough. Although porcupines can live into their twenties, they seldom get that chance. There are several porcupine predators in North America—including the fisher, cousin to the weasel, which approaches the animal from its defenseless front. Barbed quills are a sophisticated deterrent, but they’re not quite perfect.

Can bees count?

SCIENTISTS HAVE KNOWN FOR A long time that many animals can count, and some are remarkably good at it. Alex, an African gray parrot trained for years by Dr. Irene Pepperberg, understood numbers up to 6 no matter the color or shape of the objects he was counting. Alex, chimpanzees, and rhesus monkeys have all shown an ability to associate a numeral with a specific number of objects. When you realize that this means they can look at the symbol 5 and know it means five objects, it’s startling. But the idea that bees can do the same? That’s almost unbelievable.

Several experiments by Scarlett Howard, an expert in animal cognition, and a team of French and Australian researchers have shown that bees, too, can learn the rudiments of numbers. But Howard and her team started with something simpler: teaching bees to grasp the difference between the numbers 4 and 5, 4 and 6, 4 and 7, and 4 and 8. (The larger the number being compared to 4, the easier it is for the bees. The slight difference between five objects and four makes it hard for bees to tell them apart.)

A maze in the shape of the letter Y was the classroom. Bees entered the maze through a small hole in the stem of the Y, and when they reached the two arms, they could choose the one that had a sign with four objects (mostly squares, circles, or triangles of different sizes) or the one with a sign of more than four. In one version of the experiment, bees that chose the arm with four objects received a reward, a drop of sugar water. Those that chose the wrong arm received no reward. In a second version, the bees were given a reward for the correct choice and a punishment, a drop of bitter tonic water, for the incorrect choice. Bees in the second trial learned much more effectively. (This should not be taken to mean that all learning should be accompanied by punishment—they’re bees!)

Did You Know… Howard’s approach of teaching bees