Yep. This is their normal aspect. The ribbon species is named the "Venus belt", and the round ones are called "Sea grapes" or something like that.
And they are nor just bioluminiscent, they are strongly bioluminiscent. Cilia adds motion to the spectacle and maybe can change its color, but they definitely can turn on and off the lights. The cilia pads are used mostly for movement.
Many of this animals live in places without much light and do a vertical migration at night, each night. All are carnivores of small preys and is assumed also that they use light to lure its preys near their sticky longlines. Very abundant and probably one of the zoological groups were we could still find suddenly thousands of news species, but studying them is a nightmare. They literally melt when manipulated or in the microscope. At the sea, if they are cut the biggest chunks can regrow a whole body.
Its chemical lights can be used by us to detect toxics in the water. They react to contaminants making the luminiscence much brighter. Just as if they were alarmed and trying to warn other.
I wonder just now, if there is a hidden language there, like with bees dancing to communicate with other bees. Who knows. The problem is that they don't have eyes (If I remember correctly) so would need some other mechanism to see the lights. Maybe chemical.
Is a good example of how trying to equal how other animals experience the world with our experience is a mistake. Imagine seeing light with your tongue. This animals could even not be aware that they are bioluminiscent.
Their bioluminescence could be defensive. They themselves developed a countermeasure for blocking the light emitted from luminescent prey they ingest.
It seems that emitting light when eaten is a final defense to attract the attention of your consumer's predators to protect others members of your species from a similar fate.
The "Venus's girdle" is a long thin flat belt-shaped thing, but it is not wormlike. It has no head, no sense organs or anything, and the "mouth" and other main organs are in the centre of the belt, not at one end like a worm or a snake -- or you.
Most ctenophores are called "comb jellies"; one group is named "sea grapes". They are hard to generalise and not all are like this by any means, but most tend to be small, and egg-shaped, possibly with protrusions. Most tend to have 2 long trailing tentacles they use to catch food.
Most don't have muscles. They swim using bands of cilia,which are the same fine hairs that unicellular organisms use to swim, and that line your bronchi and throat. Your body uses cilia to propel mucus out of your lungs and up to where you can cough it up.
Comb jellies' cilia are in long lines, usually 8 rows. They move like a Mexican wave in a sports crowd. The light refracting through these near-microscopic beating hairs looks like they flicker with rainbows. Thus the name, comb jellies. They are often radially symmetrical along the line from mouth to other end.
That's all they have; no legs, no fins, no eyes, no dedicated sense organs. Most are not bioluminescent, but like I said, there's pretty much nothing you can say about comb jellies that applies to all of them. One type is an internal parasite that looks like a worm, although internally it's nothing like a worm. (That one is not 2-way symmetrical like us and most animals; it's four way symmetrical. It is alien compared to all other wormlike things.) Other parasitic ones are just small branching bags that don't move.
They are about the only multicellular animal that swims with cilia. They are so unlike all other multicellular animals it's just about possible that they evolved the whole plan of being multicellular entirely independently.
They look like jellyfish but are nothing like them.
Jellyfish have lots of tentacles; those comb jellies that have them, have 2, no more, no less. The tentacles don't sting; they are sticky, and the animal catches tiny plankton this way and pulls them up to its mouth to eat.
One type, Beroids, have a mouth they can close, and they can actually swallow other smaller jellies (comb jellies or jellyfish). Their lips zip shut from the edges and they have more cilia inside to propel the prey down their "throat," but they can't chew.
Some have muscles and can flex and move. Some but not many sort of swim this way, like the Venus's girdle. A very few stick to the bottom and stay there.
Comb jellies tend to have a front end and a back end, but most have no anus, just 1 hole; any food waste is vomited. But, rather wonderfully, some form an anus only when they need to poop and then it closes up again, "heals" shut, totally gone.
They are not really alien; their genetic code is the same as ours, although they don't do things all other animals do. For example their nerves do not have synapses, so they don't need neurotransmitters to carry signals across the joins between nerves. They don't have joins. Their nerves are a continuous mesh, with long lines of cytoplasm dotted with nuclei, not divided up into separate cells -- the same sort of structure as most fungi, but flexible.
I think they are beautiful. Little was known about them when I did my biology degree, but I got into them about 5 years ago and read a lot about them for a while. They are like nothing else. Even the parasitic ones, while kind of nasty, are deeply weird.
Roman legions marched around 30 km/day [0], carrying their own supplies, food, weapons and armour, needing to spend time making and breaking camp each day.
Modern European pilgrims on the Camino de Santiago seem to do about 20 km/day [1] and it's considered tiring but accessible by average people, not serious hikers. They carry less of their supplies and do not need to fortify their camp against barbarians.
Roman soldiers were presumably fitter and better trained than the average Roman (though maybe not by much, since everyone worked manual jobs). Maybe that's enough to account for the difference.
> Modern European pilgrims on the Camino de Santiago seem to do about 20 km/day [1] and it's considered tiring but accessible by average people, not serious hikers.
Yeah, because they sit in the Albergue half of the day. You need to start looking for one around 4pm or it will be full because people tend to stop walking around that time. It’s also an activity that mainly retired people do.
You can easily do 40 km/day on the Camino routes with manageable elevation (the coastal ones).
You’re right about the equipment weight though, I can’t imagine what a Roman soldiers full pack must have weighed with the textiles of the time. On the Camino, you don’t really need to bring anything except some clothes.
I see the point with the camp but on the other hand after the third day you’re more limited by your feet, not the time, so you would still have enough time for that in my estimation.
i’ve walked the via francigena and the italian section has quite a few sections of ancient roman road. they’re admittedly not contiguous, and are worn more extensively now, so i don’t get the same overall experience of treading on the stones for kilometers as they would have.
i target 35km/day with a 40L pack and finish my segments within 6-7 hours. asphalt, dirt and grass, and hiking trails (rocks, roots, dirt, etc) are the most standard surfaces and, to be honest, they’re all exhausting in their own rights so a change in surface is always welcome.
i can’t imagine marching most of this with near double body weight and then having to make camp.
Probably better to compare "A random Italian" rather than "A random Westerner", the Americans and other car-focused cultures kind of drag down the average a bit too much otherwise.
Hmm, thats a sad read. But I am not buying 'its the industry' in 2026, this is caused by folks who should and could do better but couldn't be bothered. Its also indicated in the article, young people know its junkfood and know long term effects but simply don't care. If wanting to point fingers aim them at society as a whole, junkfood was well recognized problem 10-15 years ago when these kids were being born.
Mine was a quip, but if we want to go deeper: like any phenomenon, it's obviously a combination of cultural, economic, and social factors; but it's hard not to take the marxist view that it's all about the economy when we get bombarded every second by advertising for food, the composition of which is largely dictated by considerations about profit margins. Even pasta is not produced in the same way as 80 years ago, not even from the same ingredients (half the wheat used in Italian pasta now comes from Canada and other places).
Well, you are completely correct of course. That being said... even as an european, I prefer, forge myself and push on my kids a different path - don't wait for the system to make your life great, system is flawed to the core due to process we keep using to promote elites to full power (to make it short - nice good humans don't stand a chance in the race of power, society voted for loudest sociopathic assholes doing primitive sweet talk and thats enough, again and again).
Take ownership of your life, and inspire others to do the same. Make choices, understand consequences as much as reasonable, and there is comparatively little to complain.
When I look around since I am not the youngest, the most miserable people are those who just sit back in their 'comfort zone', and expect above to be fixed for them. It ain't coming, their life is a pale shade of what-could-have-been, health goes to crap, so does mood and everything else. Its not comforting place in any way, they are just too scared to experience any form of discomfort to move away from it, and often look for similarly-minded echo chambers where they went their endless frustrations from life they chose for themselves.
I agree state and regulators should be doing their part, massively better, but so should all of us. Those that do have usually much better and longer and happier lives. What more reasons does anybody need.
ehhh Italy is sadly one of the most car-dependent countries in the western world, topping the number of vehicles per 1000 people in Europe (excluding microstates). No one's safe
I wanted to walk from one town to another. 15 kilometers. It was on a road where cars would go past literally 15 centimeters from you. No shoulder and because of the guardrails no ditch to walk in either. I didn’t do it, took the bus.
When I was in my late teens, I used to hike with a 15 kg backpack (with the technology of the late 80s). I could walk about 15 km in average hills over 8-10 hours.
I've walked for 8 hrs before, wearing modern sneakers on roads with vehicular traffic, and travelled about the same distance estimated by Google Maps. I'd estimate the Roman would like be able to travel in the same duration, barring other extenuating factors (like Caesar staging a revolt against the Senate and crossing with his legion right in front of your planned route), with worse shoes but more walk-friendly roads.
Asphalt/concrete isn't either. Gravel or packed dirt is way better.
That said 30km/day is very real, even in mountain country. It takes 6-7 hours, the rest is resting/gawking/laying on a mountain watching the sky (or trying furiosly to find that effin trail on osmand). I walked that a few times a week when I lived in Montenegro, and that was 50/50 roads and mountain trails from sea level up to 700m-ish elevation and back. No fancy shoes, no prep but for a hat and couple bottles of water. After a third walk or so it isn't even exhausting.
Sure, but I'd imagine the average human could walk substantially further on flat modern roads in modern footwear than on cobblestone with ancient sandles.
You use 10–20% more energy for just mildly uneven surfaces - probably more for roman cobblestone.
Actually no. Uniform flat surface is tiring compared to a trail even in best shoes. Try walking 10 km on hardtop then compare to walking same distance on unpaved road.
For shoes we also went not too far: Merrel sandals basically replicate roman caliga with modern materials. And it's not like you can use even halfboots in mediterannean unless it's winter - it's just too hot.
ETrade also started recently to include that disgusting thing in their News feed for watch lists -- as if it can really predict anything, with no way to turn it off (AFAICT). It's clear that it's being pushed in many directions.
I can't understand why this company won't rebrand itself to something a bit catchier or better-sounding name than DuckDuckGo -- who the hell wants to say that ? Unless it's a self-selection filter...
One thing that I am glad to have been taught early on in my career when it comes to debugging, especially anything involving HW, is to `make no assumptions'. Bugs can be anywhere and everywhere.
I wonder if they had meetings or 'design committees' to find the most optimal shape with respect to the ease of killing prey eventually.
One possibility on origin (totally made up by me) could be that there were large stones lying around already as debris from e.g. earthquakes, celestial events and such and some groups took advantage of this and later people iterated upon it.
As a supporting point, I think it's connected not only with mental functions, but also our senses.
I have a weak memory in general, but I always remember the most mundane things in my life that I had no idea I still contained in my brain, triggered by a specific smell.
Another example is that when I moved to a new street, while crossing one road, I stumbled upon the edge of tram road and almost fell. Two years and counting, my brain always brings this memory up while passing the same point on the road..
I was adamant on using one of those health/exercise tracking devices, mainly out of distaste of our modern habit to be constantly in the know of everything, but I gotta say, since I've started using one, it's just so satisfying seeing the accumulated numbers over N months or even years!
This discussion reminds me a beautiful sentence I read in 'The Power and the Glory' by Graham Greene: "Hope is an instinct that only the reasoning human mind can kill."
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