January 3, 2025
If you’ve ever been subjected to the “why” game, chances are you’ve ended up at a point where the answer is either “I don’t know,” or “just…
because.”
I can’t offer an answer to the inevitable universal existentialism that the “why” game tends to end up at, but I can try to provide you with quick, science-based answers to questions your kids might ask over the course of your beach day or road trip down Route 6A.
- Why is the ocean blue?
Say you cooked a bunch of different shapes of pasta: penne, noodles, Spiderman shapes, tiny stars. If you strain your pasta extravaganza through an average strainer, it’ll probably catch everything but the stars. If you strain it through a basketball net, well… you’ll probably lose everything.
The reason colors exist is because of the way that the particles that make up an object “strain” different kinds of light. If all types of light pass through those particles, then it’ll be clear—like glass. If no light can pass through it, it will appear black.
Particles in water can absorb blue light, but only in small amounts. That’s why when you’re looking into a tide pool, the water is clear, but if you look out to the horizon, the water looks blue. It’s strength in numbers!
It’s like putting on a pair of sunglasses: just one pair makes the world look slightly darker. If you put another pair on top, the world looks a lot darker, and even darker with a third pair. Each pair is absorbing more light and changing the overall color (and you look very silly with three pairs of sunglasses).
- Where would I get to if I just started swimming straight across the ocean?
It totally depends on which direction you’re facing and where you are on Cape: if you swim straight out from East Sandwich beach, you might end up in Provincetown, or you might end up in Maine!
But that’s no fun. That’s still the same country. Same state, even. That’s hardly an athletic feat or an adventure, right?
Hypothetically, then, if you were on a beach on Cape Cod’s eastern edge and looked straight out, then paddled the whole way with your superhuman swimming abilities, you’d probably end up in Portugal. Because the earth is round, even if you swim straight, it won’t be like swimming straight across a map. You’ll be swimming straight along a curve. So, your destination quickly changes if you take off from elsewhere on Cape: if you went down to Chatham’s South Beach, you’re more likely to end up in Morocco, or the northwestern tip of Africa.
- Ugh, what’s that smell?
That’s how you know it’s low tide!
When you take a breath, you’re taking in oxygen, a substance that is a major part of the air we breathe and supports almost all life on Earth! Your body will process that oxygen and get rid of what it doesn’t need when you breathe out—that substance is called carbon dioxide. Lots of plants will use your carbon dioxide to produce more oxygen for you and other animals to breathe, and so the cycle continues.
In salt marshes, there are little tiny blob-like creatures in the soil, called bacteria, that make use of a similar cycle to help keep the soil healthy and nutritious for the plant life that grows there. Like you breathe in oxygen, some of these little guys “breathe in” a substance called sulfur as they break down old, dead plants and other materials in the soil. They do this to create the nutrients that living plants need to thrive, but in the process, they “breathe out” a pretty smelly gas.
This means that when the tide is low and you can see more of the layers of the marsh soil, more of that gas escapes directly into the air. So it smells a little like rotten eggs at low tide!
- Okay… but what even is low tide?
Buckle up, because this is a can of worms!
Low tide is caused by a phenomenon that extends far beyond the Cape Cod beach: gravity.
All objects—you, me, the sandwich you brought for lunch, and the earth itself—have something called ‘mass,’ which is essentially a measurement of how easy it is to change an object’s position. It’s easier to push a sandwich an inch away than it is to push the earth an inch, so a sandwich has less mass.
All objects with mass have gravity, which causes a ‘gravitational pull.’ Earth, being an incredibly massive object, has a huge gravitational pull! That’s why if you accidentally let go of your lunch sandwich, it falls to the ground. Gravity pulls objects toward earth’s center.
Imagine your sandwich is terrible. Maybe it’s peanut butter and ham. You take a bite and it totally disgusts you, so you chuck it far away from you. The sandwich will fly through the air for a bit, before eventually arcing downward and hitting the sand. What you did was give the sandwich enough force—known in this case as “velocity”—to resist gravity momentarily.
This same phenomenon is what keeps the moon in orbit around Earth—it’s always “falling” toward the Earth due to gravity, but its forward motion cancels out gravity, keeping it in a perpetual balance that we know as an “orbit.”
The moon is a massive object too, though, so its gravity also pulls on Earth. As the Earth rotates throughout the day, the moon pulls on it. It’s difficult for the naked eye to see how the moon pulls on the land, but it’s a lot easier to see how the moon pulls on water!
Say, for instance, you were the earth and I was the moon. If you’re facing me, your front and back are experiencing high tide, but your right and left shoulders would be experiencing low tide. As you rotate over the course of one day, different tides would be experienced in different parts of the world!
- Why do seagulls have ketchup on their beaks?
It makes sense that so many would have ketchup on their beaks—after just a few hours at the beach, you’ll quickly notice how sneaky some of them are at stealing food, and just how well they’ve adapted to life with human beach-goers.
But actually, that red spot is still there even after they take a dip in the ocean. At the moment, scientists generally theorize that it functions as a big red button for their hungry chicks—when parents return to the nest, chicks will peck at it as a way of saying, “Mom, Dad, I’m hungry!” then signaling to the parent who would like food. Other species of baby birds might do this by singing special songs to their parents.
And as a bonus fun fact: birds can see a greater range of colors than we can! Some studies have shown that chicks with beaks or heads that are more vibrant in their more colorful vision may be more likely to get food than their less colorful siblings. Even birds have sibling rivalries.
- Will I get eaten by a shark?
In short, no. You would have to be really, really,
really unlucky.
You might hear the statistic, “you’re more likely to get struck by lightning than attacked by a shark.” Which is true. But if you’re a bit of a skeptic and a bit of a smartypants, you might point out that if you compare someone whose never seen the ocean to someone whose primary hobby is dressing up as a seal and splashing around in the shark-heavy Gulf of Florida…well, you’re right. One person is
definitely more likely to get attacked by a shark than the average person, and those statistics don’t hold up.
But even those who are self-proclaimed “beach bums” need not worry too much about a shark attack. A surfer in the Pacific Northwest writing via Medium ran some calculations, and found that even if he surfed frequently every year for the next fifty years, he would still have only about a 1 in 136,000 chance of getting attacked by a shark. What’s more, the chances of being attacked
and killed by a shark are minuscule—the odds in the U.S. are 1 in 3.7 million, but the odds of being killed in a car accident are 1 in 84.
The fatal shark attack on Cape Cod in 2018 scared tourists and locals, despite it being the first of its kind in 80 years for the state of Massachusetts. The shock of the event, mixed with its recency, makes for a lot of renewed panic about shark attacks. And Jaws tourism in nearby Martha’s Vineyard keeps shark suspicions alive and well.
Right now, though, we have no evidence that shark attacks are becoming more common, and we have more technology than ever to track sharks. What’s more, most Cape Cod beaches have “BE SHARK SMART” signs with helpful tips for avoiding shark conditions, and in the summer, highly trained lifeguards who will implement temporary swimming restrictions if they spot seals or other dangers.
So, simply practice good situational awareness at the beach, whether it be sharks, riptides, steep drop-offs, or a deep hole in the sand someone forgot to fill in, and know that beach personnel are watching out for you. You are far more likely to have the best beach day ever than get attacked by a shark!
- Can I explore the dunes?
While the grass can be reminiscent of a Pokemon-rich field, no, dunes aren’t for exploring.
Dunes form as a result of many, many years of sand movement due to weather. Over time, plants begin to take hold and develop intricate, strong root systems that help to keep the sand in place. Over time, animal species will begin to use the area as habitat.
This ecosystem is extremely valuable for many reasons. For one, sand dunes help buffer strong waves, preventing flooding and other damage that could occur beyond the beach. They also provide habitat for some endangered species, like the piping plover that can often be found running to and from waves on Cape Cod beaches.
But as strong as dunes are against wave damage, they can be very weak to a human shoe! Not only is it easy for you to kill grass stems, but creating small impressions in the sand can make it easier for an increased area of sand to dry out and blow away, potentially exposing root systems. Roots exposed to the open air and weather are very vulnerable to damage, which can have a snowballing negative effect on the ecosystem.
So while one footprint could be luckily harmless, the next could cause catastrophic damage. It’s best to keep games of ping-pong, tag, or bocce to areas designated as safe for recreation.
- Do we have to go?
If you want to beat the traffic, unfortunately, yes. But I’m sure you’ll get to enjoy an incredible post-sun nap on the car ride home.
