Nature is Metal
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A lioness and her cubs were enjoying a meal in a tree when a clan of hungry hyenas arrived and surrounded the tree in hopes of a helping of leftovers.
One of the cubs inexplicably jumped down from the tree—an apparent attempt to flee the scene—and was instantly surrounded by the hyenas and their snapping jaws.
Link to videoThe mother lion recognized the threat of losing her cub to the hyenas, dropping the impala carcass from the tree and jumping to the ground to confront the hyenas.
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@Doctor-Phibes said in Nature is Metal:
We have two possibilities - evolution or intelligent design. The hideous grossness of that seems beyond what could reasonably occur by random chance.
Natural selection is anything but random.
@jon-nyc said in Nature is Metal:
@Doctor-Phibes said in Nature is Metal:
We have two possibilities - evolution or intelligent design. The hideous grossness of that seems beyond what could reasonably occur by random chance.
Natural selection is anything but random.
But the generation of variants is, to a degree, random. I think "genetic algorithms", for which randomness is essential and which are inspired by evolution, are a great illustration of how randomness can lead to highly sophisticated structures.
Check out this little animation of "ant colony optimization", which is about finding paths (to "food") by basically just walking around randomly, with no central control. It's a very simple but fascinating algorithm:
Here's the idea:
Link to videoAnts (initially) wander randomly, and upon finding food return to their colony while laying down pheromone trails. If other ants find such a path, they are likely not to keep travelling at random, but instead to follow the trail, returning and reinforcing it if they eventually find food.
Over time, however, the pheromone trail starts to evaporate, thus reducing its attractive strength. The more time it takes for an ant to travel down the path and back again, the more time the pheromones have to evaporate. A short path, by comparison, gets marched over more frequently, and thus the pheromone density becomes higher on shorter paths than longer ones. Pheromone evaporation also has the advantage of avoiding the convergence to a locally optimal solution. If there were no evaporation at all, the paths chosen by the first ants would tend to be excessively attractive to the following ones. In that case, the exploration of the solution space would be constrained. The influence of pheromone evaporation in real ant systems is unclear, but it is very important in artificial systems.
The overall result is that when one ant finds a good (i.e., short) path from the colony to a food source, other ants are more likely to follow that path, and positive feedback eventually leads to many ants following a single path
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@jon-nyc said in Nature is Metal:
@Doctor-Phibes said in Nature is Metal:
We have two possibilities - evolution or intelligent design. The hideous grossness of that seems beyond what could reasonably occur by random chance.
Natural selection is anything but random.
But the generation of variants is, to a degree, random. I think "genetic algorithms", for which randomness is essential and which are inspired by evolution, are a great illustration of how randomness can lead to highly sophisticated structures.
Check out this little animation of "ant colony optimization", which is about finding paths (to "food") by basically just walking around randomly, with no central control. It's a very simple but fascinating algorithm:
Here's the idea:
Link to videoAnts (initially) wander randomly, and upon finding food return to their colony while laying down pheromone trails. If other ants find such a path, they are likely not to keep travelling at random, but instead to follow the trail, returning and reinforcing it if they eventually find food.
Over time, however, the pheromone trail starts to evaporate, thus reducing its attractive strength. The more time it takes for an ant to travel down the path and back again, the more time the pheromones have to evaporate. A short path, by comparison, gets marched over more frequently, and thus the pheromone density becomes higher on shorter paths than longer ones. Pheromone evaporation also has the advantage of avoiding the convergence to a locally optimal solution. If there were no evaporation at all, the paths chosen by the first ants would tend to be excessively attractive to the following ones. In that case, the exploration of the solution space would be constrained. The influence of pheromone evaporation in real ant systems is unclear, but it is very important in artificial systems.
The overall result is that when one ant finds a good (i.e., short) path from the colony to a food source, other ants are more likely to follow that path, and positive feedback eventually leads to many ants following a single path
@Klaus said in Nature is Metal:
@jon-nyc said in Nature is Metal:
@Doctor-Phibes said in Nature is Metal:
We have two possibilities - evolution or intelligent design. The hideous grossness of that seems beyond what could reasonably occur by random chance.
Natural selection is anything but random.
But the generation of variants is, to a degree, random. I think "genetic algorithms", for which randomness is essential and which are inspired by evolution, are a great illustration of how randomness can lead to highly sophisticated structures.
Ok, but natural selection is downstream from the (epistemically) random process of mutation. Like the reward mechanism of food discovery is downstream from the pseudo-random movement of the ants.
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@Klaus said in Nature is Metal:
@jon-nyc said in Nature is Metal:
@Doctor-Phibes said in Nature is Metal:
We have two possibilities - evolution or intelligent design. The hideous grossness of that seems beyond what could reasonably occur by random chance.
Natural selection is anything but random.
But the generation of variants is, to a degree, random. I think "genetic algorithms", for which randomness is essential and which are inspired by evolution, are a great illustration of how randomness can lead to highly sophisticated structures.
Ok, but natural selection is downstream from the (epistemically) random process of mutation. Like the reward mechanism of food discovery is downstream from the pseudo-random movement of the ants.
@jon-nyc said in Nature is Metal:
@Klaus said in Nature is Metal:
@jon-nyc said in Nature is Metal:
@Doctor-Phibes said in Nature is Metal:
We have two possibilities - evolution or intelligent design. The hideous grossness of that seems beyond what could reasonably occur by random chance.
Natural selection is anything but random.
But the generation of variants is, to a degree, random. I think "genetic algorithms", for which randomness is essential and which are inspired by evolution, are a great illustration of how randomness can lead to highly sophisticated structures.
Ok, but natural selection is downstream from the (epistemically) random process of mutation. Like the reward mechanism of food discovery is downstream from the pseudo-random movement of the ants.
Yes. It's a search algorithm. First you generate variants, then you discard those that are shit.
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Nothing in pond is safe from the invasion from the depths below; Giant Water Lillies!
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I wasn’t aware of that behaviour in zebras. I wonder if it is common to zebras or occurs in other wild equine species?
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I know alpha male lions will kill the cubs of another male as will bears. But I have never heard of it among migratory grazing herd animals such as elk, cariboo or bison. But then…zebras live in Africa where the rules seem to be different for everything.
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I know alpha male lions will kill the cubs of another male as will bears. But I have never heard of it among migratory grazing herd animals such as elk, cariboo or bison. But then…zebras live in Africa where the rules seem to be different for everything.
@Renauda said in Nature is Metal:
alpha male lions will kill the cubs of another male as will bears
Had no idea. Amazing.
"Now look here, you Baltic gas passer... " - Mik, 6/14/08
The saying, "Lite is just one damn thing after another," is a gross understatement. The damn things overlap.
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@Renauda said in Nature is Metal:
alpha male lions will kill the cubs of another male as will bears
Had no idea. Amazing.
@George-K said in Nature is Metal:
@Renauda said in Nature is Metal:
alpha male lions will kill the cubs of another male as will bears
Had no idea. Amazing.
And the weird thing is, as soon as he’s done the mom gets frisky with him.
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“I am fond of pigs. Dogs look up to us. Cats look down on us. Pigs treat us as equals.” ~Winston S. Churchill
