adam_russell_9615 - Jun 18, 2015

They run at 0.7 meters per second? Can that be right? I cant imagine an ant covering almost a meter every second. Thats 2.5km/hr

Graeme - Jun 18, 2015

This kind of surface structure could possibly be placed on made made items such as cars or buildings to keep them cool.

Telekinetic - Jun 18, 2015

Here's how I've evolved in the drinking of hot tea:

https://www.khana...nd-spoon

asok_smith - Jun 19, 2015

So how did the millions of intermediate Saharan Silver fore-ant progenitors, say starting from its single-celled progenitor until the penultimate Saharan Silver ant progenitor, handle the heat during that "evolutionary" progression to the current heat-proof Saharan Silver ant? All of these millions of intermediate forms must have been heat-proof also, somehow.

verkle - Jun 19, 2015

This is a telling example of how evolution has triggered the adaptation of ....


Totally wrong logic! Observing a feature on a creature says nothing about evolution. We are just observing what the organism is able to do. To say that evolution and billions of years and chance created this, is to say that your beliefs are built upon the huge fantasy. Zero science involved.

Vietvet - Jun 19, 2015

@verkle

[ Zero science involved.

Every time I think you couldn't say more outrageously false you manage to do just that.

Why is a creationist idiot commenting on a science site?

noy_watt - Jun 19, 2015

This kind of surface structure could possibly be placed on made made items such as cars or buildings to keep them cool.

And if Jeb wins the election that type of buildings should be called Bush housing.

antialias_physorg - Jun 19, 2015

All of these millions of intermediate forms must have been heat-proof also

Why would you think that? And why would you think that all the progenitors all the way back lived in that same spot?

It goes like this. An ur-ant colony lives somewhere (we could go back to the first cell, but lets start with some ur-ant. The argument that will follow can readily be used iteratively for the ur-ant back to the first cell)

So one queen of these ur-ants has a mutation that allows a tiny bit of heat resistance (say, a discoloration that is more reflective than that of the other ur-ants). This allows that queen to have her nest in sliiiightly hotter areas than others - which means they have no competition for food sources there. Thousands/millions of years later another mutation is added by one of its distant offspring queens that gives even better heat resistance...allowing THAT queen to move into even hotter areas. Rinse. Repeat.
Until you end up with the Saharan silver ant.

thingumbobesquire - Jun 19, 2015

Brilliant example of how science progresses by going beyond the arbitrary bounds of human "sense certainty." Contrary to the faulty logic of reductionists like Hume.

version782 - Jun 19, 2015

Brilliant example of how science progresses by going beyond the arbitrary bounds of human "sense certainty." Contrary to the faulty logic of reductionists like Hume.


Nothing about this goes beyond the bounds of human sense certainty, it was all verified with tools that allowed them to apprehend things with their senses. Hume was an anti rationalist who said that causality could never be justified by rationality.

PhotonX - Jun 20, 2015

Totally wrong logic!...your beliefs are built upon the huge fantasy. Zero science involved.
Says the Young Earth Creationist.
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i·ro·ny
/ˈīrənē/
noun
The expression of one's meaning by using language that normally signifies the opposite, typically for humorous or emphatic effect.
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un·in·ten·tion·al i·ro·ny
/əninˈten(t)SH(ə)n(ə)l/ /ˈīrənē/
adjective-noun
Religious fundamentalists accusing science of fallacious logic.
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PhotonX - Jun 20, 2015

They run at 0.7 meters per second? Can that be right? I [can't] imagine an ant covering almost a meter every second. Thats 2.5km/hr
Apparently so, as remarkable as it sounds. Here are two quotes from a NYT article on the same species: http://www.nytime...eat.html
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In its movements across the burning desert floor, the silver ant tries to touch the ground as little as possible. Like a beachgoer who has forgotten her flip-flops, the ant alternately sprints and hips and hops, sometimes running with two of its six legs held up in the air as it navigates the too-hot sand.
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"These ants simply do not walk," Dr. Wehner said. "They sprint." The ants can run a distance that corresponds to 100 of their body lengths per second, an ability that no other animal is known to match. During these spectacular sprints, the ants even hold their breath to conserve every drop of precious body moisture. [end of quote]
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PhotonX - Jun 20, 2015

[ctd] That said, the body length of some of these ants are only 1mm, so the 100 body length metric would give us a speed of 0.1 m/s, but the larger the body length grows, the faster it goes.
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Even more amazingly, they can dash a zigzag pattern across the desert floor for up to a quarter hour, looking for dead insects, while taking sun sightings every few seconds, and from this are able to calculate the exact direction for a beeline run straight back to the next without backtracking. Even at 0.1 m/s that's a 90 meter trek, up to over 600 meters of random course changes at 0.7 m/s, while retaining the ability to return straight to the next w/o a chemical trail. I wouldn't have thought that possible, given the diminutive size of their tiny brains, but the observations say otherwise.
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I remember Douglas Hofstadter talking quite a bit about ant messaging in GEB. I think he may have considerably underestimated their cognitive capacity, but that was written, what, 40 years ago?
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deschene_2k - Jun 21, 2015

@adam_russell_9615: Actually, that speed is correct! They can only be out for a few minutes before hiding again and minimize touching the ground (as stated by @PhotonX above). Search "Sahara silver ant" on YouTube; the video looks sped-up even though it isn't. Cool! (pun intended)

mreda14 - Jun 23, 2015

This ant has six legs but only use 4 legs in order to keep cool. These legs are very long, to keep the ants away from the heat of the ground. The thermal conductivity of air is very low compared to solid. I think the trapped air among the microsized hair that cover the surface of the ant, has to strong effect on the cooling process.

mreda14 - Jun 23, 2015

The ant can keep cool by rejecting heat using three mechanism. Conduction , there comes the air with very low thermal conductivity, convection there comes the speed of the ant as it forged in the desert with the air and the highly reflective hair that covers the ant, and radiation.

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