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Comment Beautiful transition specimen (Score 3, Interesting) 61

We are predisposed to think of feathers as equipment for flying. But seeing all those flying "dinosaurs" flitting about our yard is misleading.

Reptilian scales are basically fish scales that have been greatly toughened to control moisture loss, allowing colonization of the land. But if you are a non-big dinosaur, thermal regulation is a significant problem. Feathers are basically scales that can be fluffed up or laid flat, to varying degrees, giving different insulating profiles, at the cost of possibly losing some moisture, which many dinosaurs could well afford.

The feather more appropriate for flying could have been variants that were big for display and could lay very flat. But the original purpose was not flying. Flatness is possibly desirable for: reducing insulation when desired, streamlining the body if traveling quickly through brush, making big visual displays with relatively light equipment. However a small dinosaur that jumped around trees would find that large flattish feathers would give it added control over gliding descents, which is a fabulous thing if you are in a hurry.

Comment Re:There's an obvious alternative explanation (Score 2) 261

Probably some combination of both.

If you can withstand often breathless and hyperbolic writing, I do recommend the book Born to Run, that discusses the idea that homo sapiens, in particular, are the supreme runners at long distance at moderate speeds, for the purposes of running down prey to death, which is a very effective hunting method in hot & dry climates when you have not developed good hunting weapons yet. I believe the conclusions are largely correct.

However, there is another tale that suggests hominids were semi-aquatic, due to periods of time in east African where swaths of grazing/hunting grounds were periodically flooded. The evidence is circumstantial, but intriguing IMO. Opportunity: the historical fact of the flooded areas. Bipedal movement: which is easier to transition towards from chimp/ape walking styles in water where buoyancy helps you along until your descendants legs evolve towards that style of movement, plus it is obvious very useful to keep you head and children out of the water. Our nose: because a large downturned nose of our style is a rarity, but makes sense for keeping water out of the air tracts if you are dog paddling through shallow water. (Remember: that bipedalism sucks for swimming, unless you are a very skilled swimmer; in comparison, virtually all quadrupeds can be dropped into water and make their way around and not drown.) Hairless bodies and thick subcutaneous fat layer: this is a common pattern for aquatic animals. Flat feet: good for walking in mud.

Of course, this is not either/or. Both tales could easily be true. Hairless and subcutaneous fat makes sense in both scenarios.

Comment Re:Wrong even if correct (Score 1) 252

A growing economy has a natural tendency towards mild inflation while reasonably managed. What I arguing against is what I see as an ideologically blinkered opposition to all deflation all the time always, always, always, always. Mild and temporary bouts of deflation are entirely harmless, as long as the deflation/inflation trend is quite predictable. A growing economy has an opportunity cost of money, which implies a positive interest rate which tends to keep inflation towards the positive (not always, but that is the tendency). So whether inflation is -0.5% or +0.5% matters is just folded into opportunity costs over the long haul.

As I said, deflation during crises is potentially very bad. That is why we need a gov't that keeps its books in good order during good times, so there is breathing room for fiscal stimulus and enforced inflation during bad times.

Comment Re:Wrong even if correct (Score 1) 252

I agree that people tend to overestimate both the positives of inflation and the negatives of deflation. As long as money is highly predictable in value and the inflation or deflation quite small, it probably does not matter much either way.

That said, deflation during a financial/economic crisis can very bad and can lead to a self-reinforcing economic downward spiral as crisis encourages avoiding risk, avoiding risk encourages hoarding cash, hoarding cash lowers prices, and tumbling prices causes severe risk for all new economic activity that might bring growth. Deflation during a crisis is sufficiently bad that it is worthwhile to intervene to cause some inflation.

However, this argument has been abused to justify inflation as some dire necessity at all times. For example, we could have weathered a small bout of deflation in the later 90s, due to low oil prices and declining consumer good costs from Chinese sources, with no ill effects; instead the Fed intervened to stop deflation and thereby helped magnify two bubbles.

Comment Re:Agile (Score 1) 332

This is all proponents of Agile ever say. A noun a verb and "Your doing it wrong".

Well, to be fair, isn't that equally true about Waterfall? "Plan went wrong due to unexpected problems? You did not plan enough!" Every kind of hindsight, like a more robust POC, can be swept under the rug of "better planning" after the fact.

Both Waterfall and evolutionary/Agile methods are prone to myriad kinds of failure. The more common kinds of failure are somewhat different between the two. Waterfall can encourage dangerous blindness to changing requirements, and tends to shift certain kinds of risk later into the game than is usually absolutely necessary. Agile can fool you into not realizing that important architectural decisions were made early, without full consideration.

Comment Re:TV's business model (Score 2) 220

True. It is a matter of degree, and something that exists on a continuum can be reasonably described as causing qualitative shifts. Clearly cable allowed a networks to thrive by targeting 10%-20% of the populace. Even oft criticized Fox is appealing enough to at least 40%.

Today there is almost no bottom limit. Magic algorithms can find which 0.001% of the populace you are in, and "serve you" by leading you deeper down whatever mental hole you might find yourself in one bad year. The infotainment industry does not intend harm, but encouraging obsessiveness and ill mental health may serve their bottom line, and the algorithms may "accidentally" manipulate you that way because they see you as soulless data that is supposed to be manipulated.

Are you a vegan anti-vaxxer with a degree of sympathy for orientalist revisions of buddhism and the ALF, and get scared about nuclear power? Hey! We can lead you deeper into that bubble! Love your gun-toting heritage and are scared of immigrants and big cities? We can keep you scared! Everyone can have their very own "network" in the form of a personal news feed.

Comment Re:Does this account for dark energy? (Score 1) 244

The big differences in the speed of light presumably occurred in the first picoseconds of the universe, long before there was anything like a galaxy (or even a stable atom). Very likely, almost all the slowing down of the speed of light occurred within seconds of the beginning of the universe. But the redshift numbers we seen from the most distant galaxies galaxies record events from a several billion year old galaxy.

BTW, there has been some ambiguous data about very distant galaxies that could be interpreted as a tiny, tiny change in the speed of light. The proposed changes in the speed of light are far too small to have the kind of effect you are suggesting.

Comment Re:Theory or hypothesis? (Score 1) 244

I partially agree, but the underlying issue is that many words have multiple definitions and which meaning should be clear from context. Scientists cannot police every journalist's and every layman's language, or they will get dinged for being even more highfallutin' than they already are. In this case, the meaning is adequately clear, even if the language is imperfect.

In this context, String Theory and Fast Light Theory are understood as speculative theories, that are more developed than simply a hypothesis but much less so than a well tested theory like Evolution. At least their status is well understood by practicing scientists.

To be more explicit, String Theory and Fast Light Theory are complex and carefully developed speculative ideas that (hopefully) generate testable hypotheses. That is why they do not quite fit into the word "hypothesis". If not "hypothesis", what word we we choose? Is there a word for something in between "hypothesis" and "theory"? Neither choice is 100% correct here.

I would further note that practicing physicists sometimes say out loud that String Theory is not (yet) quite real science due to a lack of testable hypotheses.

For your other point, a certain small subset of Christians like to play word games, by purposefully misunderstanding the meaning of words as easily properly interpreted in context, as a tactic to avoid discussing the meat of the issues.

Comment Re:That Einstein's name? Albert Einstein (Score 1) 244

Exactly. Einstein was simply saying that observations were always consistent for any one observer in very certain ways (and not necessarily consistent in other ways we might naively expect). Many of his thought experiments used two observers, in order to elucidate the consistencies and apparent inconsistencies. But the underlying physics is about what is true about any one observer.

There is actually nothing in physics that says so-called physical constants were always the same over time. In fact, there have been ambiguous observations about very distant galaxies twenty five years ago, that have had proposed explanations built around the idea that the speed of light was very very slightly different 6 billion years ago. I do not think that topic has been put to rest because I ran into a blurb about similar work ten years ago. Obviously if there is a measurable tiny change in the speed of light "merely" 6 billion years ago, that is highly suggestive that there could have been a huge difference in the speed of light in the very early universe.

Comment Re:AS missiles are risky (Score 1) 432

Definitely. I think small aircraft carriers are the way to go. The super carrier is built on the logic that you need a critical number of expensive big heavy planes to maintain continuous control over a huge swath of airspace. Loitering drones can do that better. I would bet a small carrier with advanced drones could be a more effective tool than a USN supercarrier in the world of ten years ago.

Comment Re:Rule the waves? (Score 1) 432

The spending of NATO countries is within the realm of reasonable. If there is a big problem, it is lack of agreement on what kind of military they really need, exactly what kinds of capabilities are necessary. A positive bump in spending does not fix that problem enough to really matter.

Comment Re:Rule the waves? (Score 1) 432

Britain (and the USA) could survive being denied economic and military access to the entire South China Sea, much more easily than China could survive similar measures elsewhere. Open hostility would pain China in a corner, where they would either have to bow to Moscow for a reliable supply of oil, or build a new massive coal processing industry that would make their present environmental problems look like small potatoes.

Comment Re:Picking up the slack (Score 1) 432

I agree. But second rate is still very good, if we are not grading on a curve. The rest of the world is third or fourth or fifth rate, or do not even rank. The third rate navies are mostly friendly to Britain. The question is whether a first rate navy is really better than a second rate navy against the likely threat Britain will face. It is not as if they are ever going toe-to-toe with, say, China without be backed up by the USN.

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