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Gigantic Fleas and Killer Fish Wait on an Alien World
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Gigantic Fleas and Killer Fish Wait on an Alien World |
11/09/09
Whit - we're not looking at concept art for the Dark Crystal 2? Didn't Jen and Kira get a ride on those giant fleas when they were moving through the forest?
No? Wrong genre entirely?
Dammit. Fooled by superficial resemblances again. #moraeriver
11/09/09
Theres an old saying among Space Truckers! Its not the giant fleas that kill you. Its the giant Rabid space dogs! #moraeriver
11/09/09
Creatures such as that giant flea (and giant spiders, giant ants, and other giant insects or Arthropoda) are not physically possible.
Has anyone noticed how elephants, large dinosaurs, and other large land animals have thick legs? That's not an oddity of evolution but a necessity because, otherwise, the creatures would not be able to support their own weights and would collapse.
It happens because weight is proportional to volume, but strength is proportional to surface area. Thus, the ratio of strength to weight is proportional to the ratio of area to volume. Since area is poportional to size squared and volume proportional to size cubed, it follows that the ratio of strength to weight *decreases* as the size increases.
Ergo, a large land animal that is scaled up without modifications in its physical structure cannot support itself.
Interestingly, this is an old argument, first made explicit by Galileo. It also works in the other direction, which explains why insects such as ants can lift and carry objects many times heavier than themselves, compared to larger animals.
Now, I know some of you will argue that the giant flea is not an Earth flea and that it may be on a planet with lower gravity compared to Earth, but neither argument is actually relevant; Galileo's scaling argument is true anywhere and for anything. Besides, look at the tree - it has a thick trunk, thicker at the bottom, suggesting a planet of surface gravity comparable to Earth's.
Sorry to be the bearer of bad news, but no such thing as "Them!"... #moraeriver
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Brynn just got served! #moraeriver
11/09/09
Ah, there it is!
Biology if B-movie monsters - [fathom.lib.uchicago.edu] #moraeriver
11/09/09
Here are few other lame impossibilities for everyone:
[www.kollectablekaos.com.au]
[phazing.files.wordpress.com]
[www.exzooberance.com] #moraeriver
11/09/09
@Roklimber: "Has anyone noticed how elephants, large dinosaurs, and other large land animals have thick legs? That's not an oddity of evolution but a necessity because, otherwise, the creatures would not be able to support their own weights and would collapse."
Yup, notice that all the time :-).
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And while your observation of the structure of the tree is correct (it is "thicker at the bottom"), your implication is that this is a tree made of cellulose. It might be that the tree is no more made of earthly materials than the flea.
In short, those who live in intellectual houses of cards should not be so quick to blow hard. #moraeriver
11/09/09
A DeLorean going 88 mph is both realistic and fun. But traveling in time by doing so is unlikely. But also fun.
Why suck the fun out of fun by not being fun? #moraeriver
11/09/09
It's all about ratios. The size, mass, and average density of a giraffe are all such that its legs and hooves can be what they are. If you were to scale a giraffe to the mass of an elephant, with a proportional increase in size, keeping everything else about the giraffe the same, it would collapse or die of overheating (elephants have large flat ears to cool themseleves off). #moraeriver
11/09/09
11/09/09
I beg to differ. I explicitly said:
"Now, I know some of you will argue that the giant flea is not an Earth flea and that it may be on a planet with lower gravity compared to Earth, but neither argument is actually relevant; Galileo's scaling argument is true anywhere and for anything."
So, unless that flea and the tree are made of diamond (a possibility, given that diamond is carbon, though it would be the wrong crystalline structure for the kind of chemistry that life requires) or silicon-based life (also a possibility, though unlikely, given the preponderance of carbon-based life over silicon-based life in the one place we know life to exist for sure), my "intellectual house of cards" has a large strength-to-volume ratio. :) #moraeriver
11/09/09
...
Why suck the fun out of fun by not being fun?"
You didn't say it before, but you said it now. :)
11/09/09
11/09/09
Me, along with the rest of science, right? Don't confuse the message with the messenger. My post was not merely my person opinion, but a scientific fact.
"the giant flea isn't possible for a different reason"
It's not possible for a variety of reasons. One is good enough, though.
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11/09/09
Oh, and hearted for reminding me of my dad's "THIS IS WHY WE DON'T HAVE SUPER ANTS" lectures back when I was eight.
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11/09/09
"Oh, and hearted for reminding me of my dad's "THIS IS WHY WE DON'T HAVE SUPER ANTS" lectures back when I was eight."
You're welcome, son. :))
Search your feelings, Luke. You'll know it to be true.
11/09/09
11/09/09
Though I have to say that I feel a bit insulted by your calling me an anal nerd. I am not a nerd! :))
Here's the thing, though. There is a line between acceptable fiction and stupid fiction.
If someone makes a movie where a normal human being flies to the sun, and survives, how many people here would *not* be complaining about a) the fact that a normal human cannot fly on his own, b) a normal human cannot survive in the vacuum of space, and c) a normal human cannot survive the sun's coronal temperature?
I'm all for imaginative and original fiction, but I enjoy it much more when it's based on what really can happen, rather than some completely off-the-wall breaking of rules.
Just because something is solidly rooted on science it doesn't mean that it is not, or cannot, be entertaining. Since no one really has tried, we don't know, but it could actually be even more entertaining than the stuff we have that violates basic scientific knowledge.
11/09/09
11/09/09
Dragonflies have wings, which provide lift, thereby decreasing the pressure on their legs when they touch land.
As for giant scorpions, the fossil you might be thinking about is that of a *sea* scorpion. Water creatures benefit from buoyancy forces.
I'm not saying that your oxygen argument is wrong. In fact, it's correct. I'm only arguing that there are other, more general reasons, why abnormally large creatures *identical* in shape and constitution to their modern versions cannot exist. Even ancient giant arthropoda, which apparently did exist, aren't the same as their modern counterparts.
Giant Fossil Sea Scorpion Bigger Than Man
[www.sciencedaily.com]
"Plus, you have to factor in the planet's gravity"
Yes, but for a given planet, that's a fixed constant. So, an ant on Earth cannot be scaled up to the size of a human being on Earth and still support its own weight. The same is true on any other planet.
Of course, if the surface gravity on planet X is much smaller than that of Earth, it could be that a creature on planet X could be much larger than a human being, but now you're comparing creatures of different planets.
Edit: Recall, though, that a planet with very low surface gravity cannot hold an atmosphere. Case in point, the Moon, with a surface gravity one-sixth that of the Earth. Thus, huge creatures (which would depend on oxygen and would have to consume lots of it) could not exist because there wouldn't be an atmosphere to begin with.
11/09/09
"Its the deseased an infected body of BABORA STREISAAAAAND thats scary"
Isn't that her current state, already? #moraeriver
11/09/09
11/09/09
"is there any way that such an organism could exist? Let's just ponder for the fun of it, as a sort of mind expanding exercise."
I wish I knew enough about biology to answer that question. See, the thing is that there are structural as well as metabolic reasons why that giant flea could not exist as depicted.
I already mentioned the most basic structural reason, but there are others.
I recommend, to anyone interested, the reading of the article pointed to by Pijus. It goes through some of those more biologically related reasons.
The Biology of B-Movie Monsters
[fathom.lib.uchicago.edu] #moraeriver
11/09/09
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11/09/09
See, the problem with arguments in favor of such a creature is that they're pretty vague. Give me a realistic model for an alien creature, based on sensible structural and metabolic requirements for the planet it lives on, and I'll be happy to concede.
Personally, I think *that* is the part that is most fun, to come up with a realistic creature, particularly for extreme conditions.
Could life thrive on Mercury? Or Venus? Or Titan? What can we expect, based on what we know of the physical conditions of those places and based on the requirements of life as we know it?
Sorry, but a mere drawing isn't imaginative enough for me.
Edit: Unfortunately, I'm not as well versed in biology as I am in physics, so I can't tackle that challenge myself.
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Have you read his "Expedition"? That's what immediately sprung to mind when browsing the gallery. #moraeriver
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