TIL: Today I Learned
- Thread starter Cutlass
- Start date
- Status
TIL - In the US they can charge you for electronic tags used to enforce bail (paywalled, but you get the gist).
TIL that the risky behavior of teenagers has parallels in otters, gazelles, eagles, and other animals, and helps them to survive as adults.
WSJ said:Off the Pacific coast, between San Francisco and Monterey, lies a treacherous area of ocean nicknamed the Triangle of Death. Sharks patrol these waters so intensely that all the local sea otters have learned to steer clear. All of them, that is, except the adolescents.
Groups of these young otters frequently swim into the Triangle of Death. Some are attacked, but most retreat safely to a nearby cove—and then go back for more. The excursion might look like a death wish, but in the long run, these dangerous forays increase the odds that the otters stay alive. They start as “predator-naïve,” biologists say, and through these tests of daring they become “predator-aware” and eventually “predator-experienced.”
At a moment of peak vulnerability, adolescent animals are hard-wired to take risks.
The two of us have spent the past decade studying the natural world for insights into human health. For the past five years, we have focused our research on how living creatures grow up. Comparing the life histories of young animals, we’ve found striking similarities across species among those who are post-puberty but aren’t yet mature adults. Adolescent animals are more likely to take risks, gravitate toward same-age peers, practice courtship moves and stray from home—often sparking conflicts with parents and siblings. Transforming goslings to geese, joeys to kangaroos, pups to wolves and children to adults—we are both mothers of teenagers—is a common phase we call “wildhood.”
We identified four essential sets of life skills that all adolescent animals, including the human kind, must master during wildhood—or else face serious, even life-threatening consequences. Whether high-school senior or humpback whale, the adolescent who doesn’t acquire at least a basic competency in each of these areas will be disadvantaged as an adult or have difficulty making it to adulthood.
Safety. Dying accidentally is a particular danger throughout wildhood. Adolescent humans are far more likely to be killed by car crashes, gun violence, poisonings, suffocation and electrocution than older or younger people. They’re more likely to drink themselves to death and five times more likely to be the victims of homicide.
Teenage skater in a skate park. PHOTO: GETTY IMAGES
Accidental mortality in adolescent animals shows a similar surge. Wild animal adolescents crash into things, drown and get lost more often than their adult or juvenile counterparts. Physically big enough to be outside parental protection, but dangerously inexperienced, adolescent animals are, to put it bluntly, easy prey. Predators specialize in hunting them. What’s more, because they’re low in the social hierarchy, adolescents are pushed into jeopardy by older, bigger, bullying peers who exploit their naiveté.
At this moment of peak vulnerability, adolescent animals also are hard-wired to take risks. Brain and hormonal changes following puberty propel them out of dens, nests and bedrooms. A 16-year-old human who Parkours up a five-story building, and an adolescent gazelle who gallops toward a predatory cheetah instead of away, are driven by similar buzz-seeking physiology shaped by natural selection.
In another parallel with human risk-taking, we found that adolescent animals are more likely to perform these risky “predator inspections” when they’re with peers. And a brush with death may be the whole point. The otters’ death-defying encounters with sharks may teach them how their predators move, smell and hunt—provided, of course, that the otters survive the experience.
Status. If you’ve ever watched an eighth-grader labor over an Instagram post, you know that human adolescents often behave as if their status is a matter of life or death. For adolescent animals it is, quite literally.
Rank achieved during wildhood can follow an animal throughout its life and even be passed on to offspring.
Reaching higher rank in the group gives an animal greater access to safety, food, territory and other resources like better sleep. Top-ranking pigeons get first dibs at available food. High-ranking lobsters swim in perfect-temperature water, conserving their energy while other lobsters waste theirs to heat or cool their bodies. Top-notch salmon have stronger immune systems.
Rank achieved during wildhood can follow an animal throughout its life and even be passed on to offspring. Adult status is shaped, sometimes permanently, during wildhood. Given these stakes, animal adolescents experience comparisons with others acutely.
Brain chemicals, particularly serotonin, signal these status shifts. For decades, serotonin’s role in shaping human mood—chiefly depression and anxiety—has been well known. We collected data on serotonin fluctuations in animals from crustaceans, fish and reptiles to birds and mammals, and found that, similarly, serotonin signals change depending on how animals compare to their peers. If the animals consistently fall to the bottom of their groups, they eventually display behaviors comparable to human depression and stop trying to compete. Animal biologists call this the “loser effect.”
Sex. Before mating, bald eagles perform a skilled aerial courtship ritual: High in the sky, two raptors speed toward one another, lock talons in midair and plunge downward, whirling like figure skaters. Just before crashing, they release their grip and swoop back up to do it all again. Mature eagles can make it look easy, but adolescents miss the mark at first. They fumble; some even die trying. After months of practice, adolescent eagles are finally good enough to do a spiral thatgets them to the next step: actual copulation.
Bald eagles practice a mating spiral
This practice period means that adolescent eagles often must wait to have sex until well after they are biologically able. Such delays between physical maturity and sexual activity occur commonly in the wild. Our study of sexual beginners, in animals ranging from moths to whales, shows a sexual learning curve across species.
Less death-defying than eagle courtship, but every bit as complex, humpback whales sing to one another over thousands of miles of ocean. Tiny fruit flies dance and chase each other. These behaviors are a necessary series of “should-we-or-shouldn’t-we” questions between two animals. Studies of mammals that are separated from peers during adolescence show serious impairment in their ability to interpret sexual signals and to mate.
Self-reliance. Adolescent wolves and other predators often launch into the adult world without having the smarts or strength to take down prey. The need to feed themselves drives learning and innovation. Overprotected birds and fish, we found, don’t learn to eat or defend themselves as well as peers that had less parental protection.
MORE ESSAYS
Yet, as we researched what biologists call “dispersal”—that is, the process of adolescent animals leaving home—it became clear that the launch into adulthood is far from a sudden sink-or-swim moment. Across species, it is often preceded by survival training. Australian possum mothers, for example, organize practice dispersals: They require an adolescent son or daughter to spend a day and night alone fending for itself. Wolf adolescents are invited on group hunts that wolf experts call “finishing” school, where older wolves teach adolescents how to coordinate the pack.
- The American Legacy of Gandhi September 28, 2019
- Religion for Adults Means Embracing Complexity September 27, 2019
- The Spotlight on Ukraine Means Trouble for Its New President September 27, 2019
- An Ancient Practice Transformed by the Arrival of Europeans September 20, 2019
For better or worse, wildhood doesn’t last forever. But this phase is not a burden to be endured, a disease to be cured or an awkward period to be avoided. It has a purpose, shaped over 600 million years of evolution. To become mature, animal adolescents must use the time to learn and practice the key skills of life. To grow up into adults, our teenagers must do it, too.
Ferocitus
Deity
Sick and tired of how slowly your program runs because it must generate billions of random normal numbers?
Then abuse the Central Limit Theorem, while still remaining firmly within CFC language guidelines!
Just sum 12 uniform random numbers from [0.0, 1.0) and subtract 6.0.
double n = 0.0;
for ( int i = 0; i < 12; ++i ) {
n += Uniform_Random();
}
n -= 6.0;
return n;
Voila, an approximately N(0,1) random number!
You're all very welcome.
Then abuse the Central Limit Theorem, while still remaining firmly within CFC language guidelines!
Just sum 12 uniform random numbers from [0.0, 1.0) and subtract 6.0.
double n = 0.0;
for ( int i = 0; i < 12; ++i ) {
n += Uniform_Random();
}
n -= 6.0;
return n;
Voila, an approximately N(0,1) random number!
You're all very welcome.
Ferocitus
Deity
Broken_Erika
Play with me.
Unfortunately, yes. But if you're interested in science fiction that features a space elevator, I recommend Mercury, one of the novels in Ben Bova's Grand Tour series. The protagonist is an engineer who manages to get a space elevator built, but shortly before it's slated to be declared operational, terrorists destroy it (killing millions of people in the process). The engineer, Mance Bracknell, is charged with mass murder and exiled from Earth (at that point it hadn't been proved that terrorism had anything to do with it).
From that point the story veers into Bova's version of The Count of Monte Cristo, as Bracknell struggles over the next 10+ years of his life to find out what happened and get what he considers to be justice. The settings in the story include Earth, the asteroid belt, the lunar colony of Selene, Mars, and Mercury.
The concept of the space elevator is shown to involve a lot more issues than just the engineering aspect and getting it built. Politics factors into it, and the possible consequences of it ever crashing to Earth (remember that just because it's in geostationary orbit, Earth is still rotating; interfere with what's holding it in that geostationary position, and physics takes care of the rest).
That's a question I heard asked back in the '70s. Some people were against the idea because they thought the sunlight we'd get afterward would be contaminated.
Hydrogen atoms. Space isn't really as empty as we think, and oceans don't have to contain water to be oceans. They just have to have the same properties.Yes, one tacks against the resistance of the water. But there's no ocean in outer space.
So there's really no Majipoor?hobbsyoyo said:
(google Lord Valentine's Castle, by Robert Silverberg)
Cats observe our habits and learn to predict our behavior accordingly. Sometimes they prefer our behavior to move along a bit faster, so that's when things happen like it's a few minutes before the alarm clock goes off, and Maddy's thoughts run like, "You're going to get up soon anyway, so what's the difference? Come on, already!" and she proceeds to wake me up by licking my nose. Her goal is to get me up and putting food in her dish, and sometimes it works. Sometimes it doesn't. Sometimes I get annoyed if she gets a whisker up my nose (that hurts).
I've always been annoyed by one of the lines in "Ode to Spot" (a poem written by Data in one of the Star Trek: The Next Generation episodes). "Though you are not sentient..."
BS. Cats are sentient. So are many other non-human animals.
I take it you haven't met many service dogs.I know that cat people are really overly protective of their pets (who can't become aware of what others write on the web) but imo cats do not seem intelligent. Certainly they are far smarter than dogs, but that doesn't mean much; dogs are among the dumbest creatures on earth :/
I take it you haven't met many service dogs.
Certainly some dogs are not dumb, but apparently the majority of the species is
Ferocitus
Deity
They were, then they weren't, and now, according to two boffins at Cambridge Uni, they are feasible.
A couple of months ago they submitted this paper.
Zephyr Penoyre and Emily Sandford,
THE SPACELINE: A PRACTICAL SPACE ELEVATOR ALTERNATIVE ACHIEVABLE WITH CURRENT TECHNOLOGY
https://arxiv.org/pdf/1908.09339.pdf
It is still to go through peer review, so if you're really interested keep an eye on the latest papers in Acta Astronautica. It should bob up there if and when it passes muster.
https://www.sciencedirect.com/journal/acta-astronautica
Now I know why you say that your cats are your children.
Certainly some dogs are not dumb, but apparently the majority of the species is
Not dumb, infantilised.
Pet dogs get treated like children. Working dogs tend to act more intelligent
What's the point of having a cat if you don't allow snuggling and cuddling? Some of my cats have been face-lickers, and others haven't. It's just how they choose to express affection and have discovered that it sometimes works to get my attention diverted to something they want me to do (ie. getting up and feeding them).
It was hard on Maddy in the ten days following my eye surgeries. When the surgeon heard that I have a cat, he forbade allowing her to sleep with me, in case she accidentally poked or bumped or licked my face. So I had to shut her in one of the back rooms when I went to bed.
hobbsyoyo
Deity
- Joined
- Jul 13, 2012
- Messages
- 26,575
They are still used in the US - doctors and other on-call people use them because the frequencies used by beepers penetrate buildings and basements far better than cellular signals.
aimeeandbeatles
watermelon
- Joined
- Apr 5, 2007
- Messages
- 20,112
A lot of doctors still use fax machines, too.
Traitorfish
The Tighnahulish Kid
I encountered this recently; my fiance's pharmacy was having issues with its computer system that prevented them from accessing prescriptions, but told her that she can ask her doctor to fax it through. I suppose for medication that is required urgently, having a back-up that isn't going to go down short of a major natural disaster is very sensible.
As I *non-sarcastically* said, yes, this is why ‘your cats are your children’.
hobbsyoyo
Deity
- Joined
- Jul 13, 2012
- Messages
- 26,575
Yup, our doctors still use this as well. The rational they use is that it allegedly a more secure system even though the evidence doesn't back this up in any meaningful way. I think the real reason is no one is forcing them to modernize or to use their absurd prices to improve service instead of just padding shareholder pockets.
I don't know, in the summer before last down here it took anywhere between 1 and 6 hours to get a WhatsApp message to anybody outside the megacity, while using IRC or vBulletin forums we could have a back-and-forth with a second or less delay with people in Chile and the US.
- Status
