Why Are Sloths So Slow?
slothconservation.org
slothconservation.org
Wow. Didn't it get hurt from the tree falling down on it?
>rapidly ascended
Doesn't sound very slothy.
However… their diet is so calorie low that they can actually really harm themselves by exerting too much energy, basically can’t replace it quickly enough.
They are so evolutionary evolved to move slow, I saw one scared and struggling against a vet that it was still moving in a slow motion defense.
Side note, that vet only had 4.5 fingers on one hand. A sloth bit half of one off years ago in a slow motion amputation. Very sharp teeth (they move slow) and very powerful jaws.
The joking immediately stopped and he stared at me deadpan and said "not funny. No one could do that."
It was amazing.
After having had that voice on well-produced nature content for my entire life, I find most other nature-documentary voice-overs quite jarring. Even the British ones (Tom Hiddlestone had a go recently IIRC).
I will say though that I enjoyed Paul Rudd doing ‘Secrets of the Octopus’. Didn't overplay it, just did a really good job IMHO.
I have lots of time for well-meaning parody though, such as this one about the majestic Australian White Ibis (otherwise known as the bin chicken) - https://www.youtube.com/watch?v=w4dYWhkSbTU
"Zoo Quest" is his first nature documentary series, from 1954(!), very different in style from today's nature shows. I remember as a child seeing clips of it when it was already ancient history -- grainy black-and-white footage of a very young and athletic Attenborough practically wrestling a lizard.
It was originally broadcast before colour TV existed in the UK (funnily enough, Attenborough was the controller at BBC 2 when they pioneered colour broadcasting) so everyone assumed it had been shot in black and white. But in 2016 someone discovered that much of the original footage was colour film. The restored version is absolutely gorgeous.
Yes! I think it's not just familiarity, what makes him definitive is a combination of factors: fantastic voice and deep domain knowledge and his very clear love and enthusiasm for nature.
You can get an actor with a great voice, Morgan Freeman or Tom Hiddleston or whoever, but you always know they're just reading from a script and probably don't know any more about the animals than you do.
And there are other experts with a knack for presenting, people like Mary Beard, but you can't just transfer that knowledge to a completely different subject area.
Edit: It seems as though others do say slow-th, but it's not something I've really heard from the younger generation
Which makes me think: i am surprised that is not an excessively used term in the startup / brotrepreneur world...
breadth, chillth, coolth, dampth, dearth, depth, filth, health, height/heighth, illth, length, roomth, ruth, strength, troth, truth, sloth/slowth, warmth, wealth, width, wrath, wrength, youth/youngth
(As a foreigner I’m curious what the original adjective was for filth, length, ruth, wealthy, wrath).
Looked the ones I didn't know the adjectives of up on wiktionary: foul, long, rue, possibly the archaic "wele" (but there are multiple etymological paths), and basically "wrath" but pronounced slightly differently going back thousands of years.
Weal is defined as happiness, well-being, prosperity, or that which is best for someone.
For example, apparently "filth" comes from the equivalent of "foul".
I am a little surprised that ruth is spelled that way instead of like rueth, which seems more like how I would expect it to be said.
strength <- strong
But enough jocularth can eventually result in -th becoming productive again!
I've heard this said, and seen this in plenty of codebases. `let width = 10, heighth = 10`
Its intuitive match to "width" makes me wonder why it ever became "incorrect."
I read this whole article and it’s still not clear to me _why_ they’re slow.
I’m genuinely curious! It seems like this article just lists a bunch of facts about sloths. But doesn’t say why being nearly blind or having a slow metabolism gives any evolutionary advantages.
1. With their poor eyesight, if they were fast they'd half-blindly get into trouble and fall to their deaths or whatever, so it's kinda-sorta beneficial given that other constraint.
2. Being slow-by-design reduces calorie needs, meaning they can survive eating a smaller amount of stuff and stuff that other animals also don't want as much. This lets them fit into a low-competition niche.
3. Most nearby predators are looking for fast-moving targets, so being slow helps them avoid being detected.
Similar to why some small things become giants and some giant things become smalls, it all depends on the niche, and the input conditions before transformation through time and genes.
4. Having little muscle mass, and with more than a third of their body weight being half-digested leaves, there's not much worth eating.
Surely a sloth is not the primary prey of any predator. More of a desperation move?
They hide from predators like jaguars, ocelots and eagles, but why did no predator that grabs them from the trees evolve?
(Just trying to learn from them and their amazing ability to stay under the radar for 65 million years :D)
Isn't that what the eagles already do? https://www.youtube.com/watch?v=i0zrah5JEBM
Evolution is basically a random-walk algorithm to find combinations that work.
It's because there's no singular reason for it. Evolution is blind (pun not intended), doesn't have motivation or reasoning. I think the article makes a good job explaining the set of evolutionary forces which likely pushed sloths into this direction.
> But doesn’t say why being nearly blind
The article mentions that this mutation already happened to the sloth ancestors, which lived on the ground. It's possible that it provided some advantage to those, or perhaps it didn't actually matter much (perhaps they were nocturnal?)
I imagine the author accidentally thought it was obvious. Having a slow metabolism is an evolutionary advantage in the same way not spending money is a financial advantage. It uses little energy and energy is usually the limit on what animals can do. If you don't spend much money, you don't need to earn much and can just exist. Being a high-earner-high-spender is probably a more efficient equilibrium, but spending nearly nothing works well enough to survive and if someone can spend less than they earn eventually they get wealthy.
If sloths don't do much, they don't need to eat much to balance out the energy expenditure. If they don't need to eat much, they can take less risks and tend to survive. Being slow is one aspect of their strategy of not needing to eat much.
Well they started early and had already arrived before all of us got here.
No reason to get in a hurry after that.
[0] https://www.goodreads.com/book/show/34211802-the-unexpected-...
If that were increased, we would instead see a series with smaller and smaller non-zero values for fullness as we approach maximum sloth fecalness.
So...what if the vile-smelling feces of the sloths was not "natural", but due to a variety of microorganisms which had colonized their intestines?
it's handy for sites that don't put anchors on all their headings etc... or like this to link to random place in body text
The human biceps is a good example of this. From a mechanical standpoint, where its insertion is like barely below the elbow joint, the bicep has extremely poor leverage, to the point where it needs to exert much more force than the hand does probably by a factor ~20-50. If it somehow went diagonally between the shoulder and the wrist, maximizing leverage, ignoring everything unpractical about this you'd be able to curl a small car engine. The downside is that a diagonal bicep would give us about 40 degrees of range of motion for the elbow and we'd be completely unable to throw things.
Big exception is jaw muscles (which are set up closer to that bicep thought experiment). Since they don't need to "escape" from anything and can sacrifice a bit of range of motion, they can afford to optimize for strength and endurance.
In Brazil you can visit caves featuring scars on the rock from the pre-historic giant sloth’s claws. This funny animal descends from that!
https://oglobo-globo-com.translate.goog/google/amp/brasil/no...
Then again, something similar probably happened many times in evolutionary history, and the victim species died out as a result. So if one of those predators would exist, we wouldn't have sloths. I guess this leaves them vulnerable to invasive species?
Of course, it had the armor of a tank and a 20 cm neck with a bolt cutter for a mouth.
Evolutionary traits usually come with a tradeoff, and if a predator evolved to be able to catch sloths more easily it might make them less able to catch the juiciest prey, so overall it might be more worthwhile to focus on the other animals and leave sloths off the table, so to speak.
Too low contrast; didn't read
https://nationalzoo.si.edu/animals/pygmy-slow-loris
In America, you can find them at the DC zoo in a shadowed alcove under red light to simulate night time during visiting hours.
But given their lack of thermal regulation, I wonder if this leaves them especially vulnerable to climate change.
Feels like evolution is not as perfect as we want to believe sometimes.
Could something similar happen with sloths? Maybe their eyesight would improve quickly?
Weird phrasing. All of them having something that is rare means it is not rare at all, right? And if all of them have it, it is not a “condition”, it is their genes, how they are.
Most people think of evolution as a string of improvements, however you can get negative traits in a population from a large enough genetic bottleneck or spread by being next to a very useful mutation. So it’s not necessarily an advantage for them, it could have just been bad luck.
Alternatively, there could have been some selective pressure for it as a means of improving night vision or something, we just don’t know.