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Comment Re:Somebody didn't get the memo... (Score 1) 279

Not really sure where you got that from. Dinosaurs are descended from fish. You could say "humansd are fish" too,

I do.

but descended from doesn't mean we are one by any common definition of "fish"

I do point out that the context that I am talking is the terminology of cladistics. Which, being logical, will eventually take over.

Osteichthyes (colloq. bony fish even though it includes things not called fish)

... such as elephants, titanosaur dinosaurs, whales, avian dinosaurs and Ken Ham.

We also have jaws, which crucially hagfish do not.

I did actually use the term "gnathostome" in one of my drafts of that sentence. The details of those less-derived parts of the vertebrate phylogeny are still a bit unsure in terms of what order things happened.

whereas colloquial classifications are unlikely ever to

That is a problem for colloquial classifications. Are whales fish because they have bone, or are they fish because they live in the sea? In which case, mud skippers are not fish, and the case of all fresh-water fish is very open. As you say, set operations are useful, but you then have to include in your description of an organism the list of which set operations you have considered useful to apply. The point of cladistics is to try to restrict that list of set operations to those which can be observed in the organism itself through it's morphology or genetics.

Comment Re:Somebody didn't get the memo... (Score 1) 279

I disagree. Birds are no more dinosaurs than dinosaurs are fish.

I agree with your grounds for disagreement, but disagree with your conclusion. Birds are indeed no less dinosaurs than dinosaurs are fish, because, as you seem to forget, dinosaurs are fish.

So are we. (Assuming that you are a human, a mammal, etc ; I think the acceptance of my blood by the human medical authorities indicates that I too am human.)

What distinguishes fish from elasmobranchs (sharks, rays and other less-derived gnathostome craniate vertebrates) is the presence of bone (as opposed to cartilage). We have bone, trout have bone, birds have bone (and non--bird dinosaurs had bone - the histology where preserved is unarguable) ; elsamobranchs don't have bone. Also, elasmobranchs, humans, fish and chickens (with a little bit of persuasion, to suppress the developmental silencing of tooth-development genes) have teeth, which hagfish do not have. Welcome to the wonderful world of cladistics, the science of phylogeny. "Descent with modification," as Darwin put it. If evolution is true (which it is), then traditional classifications of animals will eventually need to reflect that. Which does happen, even in the irrationality of English - you might remember that we (our species) had been hunting whales for several centuries and classifying them as fish before anatomists received enough material to identify them as being mammals. Classifications do change. I'm just trying to get that change started in general language, since the argument (over cladistics as a way of classifying evolving organisms) is finished in the scientific community.

Comment Re:Idea!!! (Score 1) 136

and Japanese cars by the laughable 10-15 cycle, where the highest speed involved in the whole cycle is 70 kph (under 45 mph), with an average speed 1/3rd of that.

What are actual driving conditions like in Japan? What are actual driving speeds?

The last time I saw anything about driving in Japan, it was a footnote to a programme that pointed out that before you could buy a car from any Tokyo dealership, you had to present them with your parking permit. No parking place? No car. One parking place, it displays the registration number of the car permitted to park there. Same for the second parking place, which had to be a different car. All tied into the tax and insurance system.

Meanwhile, for commuting to and from work, essentially everyone used the trains. Because there simply wasn't enough road space to move the population with buses, let alone cars.

So a top speed of 70kph and an average of 25kph isn't necessarily unreasonable.

Comment Re: Really, this happens in America? How?? (Score 1) 179

Three nines would be wildly optimistic. Two nines ... that's the point at which I'd have to actually write a script to check what my own link's up time is.

(Thinks : 1440 minute per day, so two nines would be 1426 minutes. Am I actually down for a quarter hour per day? Probably. Rarely more than 2-3 minutes at a time, but multiple times per day.

Comment Re:Somebody didn't get the memo... (Score 1) 279

Going to uni in the UK, the lecturers recommended books, none were mandatory and the library usually stocked a bunch of copies.

... which were mostly kept in a separate area (at my uni) known as the "high demand area", from which you could only book a volume out for periods of one or two days. Not returned on time? Your ID would be rejected for any other books. Just to persuade you to return the volume to the "high demand area".

Comment Re:Radiation? (Score 1) 250

another [app] can detect radiation.

There are other ways of detecting radiation than Geiger counters (electrometers, for example), but I struggle to work out how or why the appropriate sensors would be included in a regular mobile phone. I could almost see the point of a USB-powered device, which you might communicate with through an application. But you still then need to look carefully at the calibration procedures and reference materials for it to be much use.

Amazon do such things for about $600, so I guess it's shoddy writing rather than someone successfully breaking the laws of physics.

Comment Re:Mind boggling (Score 1) 96

It's not entirely unreasonable to think there will be life here until the sun swallows the earth up entirely

Actually, it is entirely unreasonable to assume that. For hundreds of millions of years before the Sun "swallows the Earth" (itself still only about a 50% probability ; predicting the exact degree of stellar swelling in the red giant phase is beyond current astrophysics), the Earth will be baked to the degree of Mercury, then Venus, then maybe to the point of a magma ocean then erosion by the plasma of the Solar atmosphere.

But hundreds of millions or billions of years before then, the slow increase in Solar output will increase terrestrial temperatures (research the "faint young sun paradox" for more info). Note - we're talking about changing Solar luminance, not changing the Sun's size. The size may change a little, but only a few %. The big growth of the red giant phase is still far in the future.

You may have noticed that to maintain our current approximately 15 K of global warming (from atmosphere-free equilibrium to our current temperatures, globally averaged), over the last couple of billion years the carbon dioxide content of the atmosphere has gone down from multiple percent to multiple parts per million. Eventually the reduction in global warming achieved by that reduction in CO2 will stop - because there won't be any more CO2 to remove from the atmosphere. At that point, the increasing Solar flux will start to increase surface temperatures (regardless of what humans do about it, except geoengineering) and the next greenhouse gas will start to take over. That is water vapour. And as temperatures rise, the oceans will get hotter, leading to more atmospheric water, leading to increased greenhouse effect, leading to increased temperatures. The observant may spot the presence of a positive feedback loop there.

That is when it gets very hard to predict exactly what will happen. But an increasing trend (driven by the laws of nuclear fusion in the core of the Sun) driving a positive feedback loop is a recipe for runaway. Best current estimate is that it'll happen around a billion years from now (+/- 20% ?)

When that feedback takes over, the Solar system will have two baked-atmosphere planets in the inner system - Venus and the Earth.

Are you aware of life forms that can live in an atmosphere of super-critical steam and nitrogen?

==========
Actually, I'll revise slightly. I can conceive of genetically engineering organisms that could survive in the atmosphere by using gas bladders to balloon to a pressure level where the temperatures and pressures are manageable. Te bladde would probably make sex difficult. But if cephalopods can invent "copulation by guided missile", I don't see that as an insurmountable problem.
Can I conceive of such evolving naturally ? Hmmm, much harder. Portuguese Man o'War might be a workable model. Vertebrates that can give birth and nurture on the wing ... that's a big ask. I'd hesitate to say it's completely impossible, but it's a big ask. I note that we don't see seasonal (in the sense of perihelion/ aphelion) colour changes in the clouds of Venus, suggesting that Venusians of 3 billion years ago failed to make the transition when the time came for them.

The billion years in the future date relies on the details of atmospheric modelling (much more complex than nuclear reactions) ; but that the seas will boil long before the Sun starts to grow appreciably is a robust result.

Comment Re:Mind boggling (Score 2) 96

Actually we've only got around a billion years before the increasing solar temperature (due to accumulation of helium in the core) triggers a runaway greenhouse effect and ... sayonara anything that depends on liquid water.

With "geoengineering, we might be able to extend it to a couple of billion years.

Comment Re:Enron down under (Score 1) 269

They have to keep enough power flowing through the aluminum to keep it molten,

It's the cryolite (electrolytic medium) which they need to keep molten ; they can heat the aluminium any time because it'll conduct current even when it's cold. The cyrolite doesn't conduct electricity until it's near it's melting point, so you need resistive heaters to get it up there. MP of cryolite is 1285 K ; aluminium is 933 K ; keep the cryolite molten and the aluinium is taken care of automatically.

Probably they mix the cryolite with some other salt(s) to lower the MP to close to that of the aluminium, but their choice of cations would be small (need a higher electron affinity than aluminium, otherwise you put your cation into the aluminium, which you then have to refine again - waste of energy, literally), and the precise mixes used are probably trade secrets.

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