Mysterious and interesting things, first read about them after going scuba diving and seeing a few of there barely-there diaphanous whisps of creatures, with rippling iridescent spines up their sides.
Amazing to learn they were cilia refracting the light, not chemical bioluminescence, and that despite appearances they are absolutely not jellyfish!
NotCamelCase 12 hours ago [-]
So, they actually look like that as in the first video (gliding ribbon-like thing)? I can't tell if it's an animation or not, but it's so cool!
pvaldes 11 hours ago [-]
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.
learn_more 5 hours ago [-]
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.
mmooss 4 hours ago [-]
The images and video clips are amazingly well done. It's so rare the serious publications take full advantage of the medium of a web page.
mmooss 4 hours ago [-]
> Comb jellies are ancient marine predators whose hairlike extensions known as cilia refract light as they swim, giving them an iridescent shimmer. They are the largest animals known to use cilia for movement, ...
I've long wondered: What is the difference between cilia and flagella? I've found no authoritative source that differentiates them or that says they are the same (except one paper from decades ago that strongly implies they are the same). It seems like something insiders know implicitly and never bother explaining.
Because a clear distinction is lacking, I don't trust non-expert sources like Wikipedia to be consistent, tor to not confuse them or miss any nuance.
pvaldes 3 hours ago [-]
> What is the difference between cilia and flagella?
There are clear structural differences at microscopic level. they are fueled differently. In short, cilia are like eyebrow hairs, short, weak and simple. They appear in groups of tens or thousands, while flagella are like head hairs, unique or double, rarely more than three, and much longer, thicker and more potent, so faster. Structurally more complex also.
They move in a different way also. Lets say that cilia move like a pendulum and flagella moves like the ribbons in rhythmic Gymnastics
bediger4000 3 days ago [-]
Steven Haddock, a marine biologist who studies ctenophores
Interesting case of nominative determinism.
randomImmigrant 3 days ago [-]
Haddock is a bilatarian species though :P
But yes, the I suppose a call to study ocean creatures can be more compelling with that’s name.
bediger4000 1 days ago [-]
I imagine Steven Hydra was taken.
GolfPopper 3 hours ago [-]
Presumably by the Deep Ones.
6 hours ago [-]
Rendered at 21:06:00 GMT+0000 (UTC) with Wasmer Edge.
Amazing to learn they were cilia refracting the light, not chemical bioluminescence, and that despite appearances they are absolutely not jellyfish!
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.
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.
I've long wondered: What is the difference between cilia and flagella? I've found no authoritative source that differentiates them or that says they are the same (except one paper from decades ago that strongly implies they are the same). It seems like something insiders know implicitly and never bother explaining.
Because a clear distinction is lacking, I don't trust non-expert sources like Wikipedia to be consistent, tor to not confuse them or miss any nuance.
There are clear structural differences at microscopic level. they are fueled differently. In short, cilia are like eyebrow hairs, short, weak and simple. They appear in groups of tens or thousands, while flagella are like head hairs, unique or double, rarely more than three, and much longer, thicker and more potent, so faster. Structurally more complex also.
They move in a different way also. Lets say that cilia move like a pendulum and flagella moves like the ribbons in rhythmic Gymnastics
Interesting case of nominative determinism.
But yes, the I suppose a call to study ocean creatures can be more compelling with that’s name.