A weekly newsletter for all your intellectual, spiritual, and physical needs
Howdy pardners! Welcome to Volume 109 of Dovi’s Digest.
In last week’s intro, I briefly mentioned our sense of smell and the connection we have to it. So, this week, I thought I’d go in a slightly different direction.
In our modern world, there are things to which we’ve become unwittingly accustomed. Whether it’s flicking a switch for illumination, or opening a fridge for sustenance, for most of us these are just things that “are”. However, something else that has become normal for us is the amount of noise around us that we unconsciously drown out. The beep of phones, the clack of keyboards, the wail of sirens, the drone of cars, these are all things that are often audible to us, but our brains filter out (unless we actively decide to notice them). It’s an amazing ability that the human mind has, filtering out the proverbial wheat from the chaff, to make sure we focus on what’s important. Case in point, as you’re reading this, you can see your nose. Your brain just decided to filter it out as it’s not vital to your viewing experience.
Animals however are not so lucky. Not only are many of their senses more finely attuned than ours, but apparently, they also struggle to drown out background noises like we do.
Which brings us to this week’s headline article. Ever been in a pool and clearly heard the splash of someone jumping in at the other end? You’d think it’d be slightly dulled, but in fact noise travels faster and further in water than it does in air. (A very basic overview of it: Sound travels faster in water compared with air because water particles are packed in more densely. Thus, the energy the sound waves carry is transported faster. Distance is similar, but more dependent on temperature and pressure, this link explains better than I can.)
All of this means that the ocean is a very noisy place. And that’s without humans. Now, with all our shipping, our sonar, our undersea drilling, and even test bombs, animals are finding it more and more difficult to not only communicate in close quarters, but to locate prey, and link up with others of their species further afield. In the dark depths of the oceans, eyes are mainly useless, and therefore sound becomes the main sense. And we’re slowly drowning out everything. The article discusses a pod of orcas in particular, the effect that sound is having on them and their ecosystem, and what we can do to help mitigate these downturns.
Last week, I mentioned that I’m putting together a list of books that people have deemed their “must reads” and asked you for your help. Well, many of you came to the party, and there are over 50 books, both fiction and non, on the list. To view the list, you can just click here, and if you want to add to the list, you can either click here, or you can do it direct from the sheet (conveniently labelled “click here to add to this list!”).
Do you enjoy the Digest? Would you like it to get better? Then please consider sharing it, as the more articles I’m sent, the better it is. It only takes a few seconds, and all you need to do is click here 👇. Thank you!
There was ONE correct answer to last week’s brainteaser. Well done to Ariel Subotzky. The answer and this week’s riddle are below.
You may be sensed out after last week’s extravaganza of smell, so I have some other things for you in my goody bag. You can read about how we may be saved with poo, how the jeep become the go to vehicle of the American army, a north American Pompeii, a video of a helicopter catching a rocket (and why it did this), tips on how to smuggle booze should prohibition ever come about again, and what it’s actually like to live and work on a submarine. Enjoy!
Keep those articles (and everything else) coming,
Have a great week,
Dovi
And now, the articles:
An Ocean Of Noise: How Sonic Pollution Is Hurting Marine Life
Today’s oceans are a tumult of engine roar, artificial sonar and seismic blasts that make it impossible for marine creatures to hunt or communicate. We could make it stop, so why don’t we?
The Power of Shit
(Courtesy of Ari Chipkin)
Our excrement is a natural, renewable and sustainable resource – if only we can overcome our visceral disgust of it.
The Fascinating Story of How the Jeep Became America’s Favourite Military Vehicle
Soldiers may enjoy their time in a Humvee or Huey nowadays, but there is no military vehicle more beloved than the World War II Jeep.
North America’s Pompeii
In 1970, a violent storm uncovered a Makah village that was buried by a mudslide more than 300 years earlier. A newly re-opened museum tells the fascinating story of the ancient site.
Amazing Video Shows a Helicopter Catching a Rocket Booster Mid-Air
For the first time ever, Rocket Lab captured its Electron booster mid-air via helicopter.
So, You Want to Be a Bootlegger
In a 1922 Post article, an ex-bootlegger offers advice for how to break into the business.
Nukes, Nubs And Coners: The Unique Social Hierarchy Aboard A Nuclear Submarine
Getting assigned to your first sub doesn’t make you a submariner and once you become one, you’ll find yourself in a social structure unlike any other.
Quote of the Week:
“Do not live as if you have ten thousand years left. Your fate hangs over you. While you are still living, while you still exist on this Earth, strive to become a genuinely great person.” — Marcus Aurelius, Roman emperor
Facts of the Week:
It costs five times more to keep a panda than an elephant.
Humans and bees are the only species elephants fear.
Pliny the Elder noted that the stare of a menstruating woman could kill bees.
Spot removal for Pliny the Elder involved rubbing the affected part with a paste made from the ashes of a roast dolphin.
Black leopards have spots, but you can only see them in infrared light.
Puma and Adidas were founded by two brothers who fell out and went into competition against one another.
After 11 months on the International Space Station, astronaut Scott Kelly returned to Earth 13 milliseconds younger than his twin brother.
Cartoon of the Week:
Tweet of the Week:
Headline of the Week:
Brainteaser of the Week:
Among six children, each handshake is between a boy and a girl. Each of four children shakes hands with exactly two others. Each of the other two shakes hands with exactly three others. Do these children shake hands with each other?
Last Week’s Brainteaser and Answer:
In the Pet Hotel, the rooms are numbered 1 to 5, in that order. Each room can accommodate one animal and has its own light. At night, an animal who is nervous leaves the light on. An animal who is not nervous turns the light off. Each of the rooms 1 to 5 are always occupied by either a dog or a cat, and everyone checks out after a night.
a) On Saturday night, a dog is nervous if and only if there are cats in both adjacent rooms. A cat is nervous if and only if there is a dog in at least one adjacent room. It is observed that four rooms remain lit. How many cats are there at the Pet Hotel?
b) On Sunday night, a dog is nervous if and only if there are other dogs in both adjacent rooms. A cat is nervous if and only if there is another cat in at least one adjacent room. It is observed that only one room remains lit. How many cats are there at the Pet Hotel?
Answer:
a) 3 cats b) 2 cats
a) Consider three cases. Case 1, only room 3 is dark. Suppose there is cat in this room. Thus rooms 2 and 4 must both have cats. These two cats are nervous, thus 1 and 5 have dogs. Neither of these dogs are nervous, thus 1 and 5 would be dark, which contradicts the premise of Case 1. Suppose room 3 has a dog. Then at least one of 2 and 4 has a dog. This dog cannot be nervous, so would switch off the light, again leading to contradiction.
Case 2, either room 2 or 4 is dark. Let’s say it’s 2. Suppose there is a cat in this room. Thus 1 and 3 must have cats. But if this is the case, then the cat in 1 is not nervous, leading to contradiction. Suppose there is a dog in 2. Then either 1 or 3 has a dog, but this dog will not be nervous, leading to contradiction. If we started with 4, the same logic applies.
Case 3, either room 1 or 5 is dark. Let’s say it’s 1. Suppose there is a cat in this room. Then there is a cat in 2, which means there is a dog in 3 and a cat in 4. Room 5 can have a cat or a dog, but either way it is not nervous and would switch off the light. So suppose there is a dog in 1. If room 2 has a dog, it won’t be nervous, so the light goes off and we get a contradiction. So room 2 has a cat. If room 3 has a dog, then room 4 must have a cat, and then whatever is in room 5 will turn off the light. Contradiction.
So, suppose 1 has a dog. Room 2 must be a cat, since a dog in this room would not be nervous. If room 3 has a dog, it is only nervous if room 4 is a cat, which will be nervous, but that means whoever is in room 5 is not nervous, which leads to a contradiction. Thus room 3 has a cat, room 4 has a dog and room 5 a cat. This works, and is our solution – 3 cats.
b) Using a similar process as above you will find a solution when the lit room is 3 (which gives one solution of cat/dog/dog/dog/cat). Thus 2 cats.