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Ken Fabian

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Everything posted by Ken Fabian

  1. It would be possible for a more densely furred variant to arise in a less than ideal environment. But how well would it survive and reproduce compared to it's relatives? That is, would it be perpetuated and ultimately be fixed within a population? On the face of it that trait would disadvantage rather than advantage but I don't think it's always so simple. Plenty of furred mammals occur in hot climates - and even hot climates can have cold seasons and unseasonal cold periods; even if it's often a disadvantage there can be times and situations where it becomes an advantage. It may be that those times are critical. I would also expect for populations in hot places that are still relatively near to places where it is colder - hot low altitude areas next to mountains with colder climates - those who move to higher altitudes could gain advantage as SFNQuestions has suggested. There are going to be more variables than simply heavier or lighter coat; what means are available for thermoregulation - which may include panting, sweating and even, as with some Kangaroos, licking forelegs for evaporative cooling - will have a bearing. A heavier coat would hold more heat but better protect from intense sun, but does it shed water or hold onto it? If it better protects from being wet and cold, even if those circumstances are only periodic, it may be sufficiently advantageous and persist. Nocturnal or diurnal? It would matter whether the genetic differences are dominant or recessive as well.
  2. SamCogar - I've had an ongoing interest in the evolution of human furlessness and don't see anything particularly aquatic about it. Applying a kind of "reverse engineering" to body hair - paying attention to it's current functions as well as what reduced or lost functions compared to related apes, primates, mammals and considering what evolutionary processes including advantages and disadvantages could lead to the range of hairiness humans currently display - doesn't lead me to conclude there is or was anything aquatic. Comparing to other "hairless" mammals (n.b. even mole rats, elephant and rhinoceros are not truly hairless) can help in finding potential evolutionary "pressures" that may lead to that furless state but each had it's own distinct evolutionary history; they can only indicate possibilities to consider and should not be seen as anything conclusive or exclusive of other possibilities. And amongst the possibilities we probably should not leave out that dominant mutations swept through a population of clever, problem solving, behaviourally adaptive hominids without providing any disadvantage they could not survive or advantage that greatly improved survival - they just tolerated the changes. BTW, out of interest, can I ask what functions you think body hair has lost and what functions you think it currently performs? Note that I will argue if you claim it currently serves no significant function.
  3. Bender, I don't think there is any real reason to live on the Moon or Mars. I've never been convinced about ultimate survival of the human race as a realistic motivation for colonising space; if the more mundane motivations, like profitably exploiting resources by outposts of a healthy and wealthy Earth economy are insufficient I doubt the willingness of the majority to sacrifice their futures funding the preservation of a select few would would do it. In any case the nuclear powered bunker probably works better for most global disaster scenarios than colonies on Mars or the Moon. For any space colony to succeed in a lifeboat scenario role a greater than 100% technological self sufficiency would be needed. I don't know how many distinct specialisations would be the minimum for tech dependent survival beyond Earth but I suspect enough that a largish population and diverse economy would be required to sustain them. Perhaps some forms of virtual expertise and a base technology optimised for ease of endless reproduction and resistance to downhill degradation of capabilities could stand in the place of the pool of actual, working experts at the leading edge - the sort that only large populations and wealthy economies can sustain. I don't see that we could do so with what we currently have.
  4. Bender - Tourism seems unlikely to be a viable economic basis for a space colony even if it might play some minor supporting role. Just like the entertainment value of selling "reality" TV rights. But entertainment is a fickle industry and may continue to find the fantasy version, with CGI, more suited to their budgets and tastes. I suspect the more real space tourism there is the more vulnerable the illusions the fantasy/SF version perpetuates will be to being blown. If the economic transport infrastructure to support trade between planets is a huge hurdle, that for tourism, with the comfort and luxury the wealthy expect, must be at least as problematic. And no, we haven't colonised Antarctica - we have scientific bases on Antarctica, that are supported and funded by the wealth and technology of nations elsewhere.
  5. Colonising ventures are underwritten and funded because they are expected to provide tangible, ie economic, returns to those investing in them. Colonies survive by trade, or by self sufficiency but the latter simply won't apply because of the high cost, high tech minimum requirements. Those would strain the wealthiest and most technologically capable nations. Trade requires a cost effective system of transport. Neither seems a reasonable prospect for either the moon or Mars. Unlike the Earthside historical examples that made use of well established low cost transport and trade infrastructure, space colonisation requires a huge pre-investment in technologies that are essentially hypothetical. It makes fantastic (literally) fiction but it's not a sound business venture.
  6. I would not be surprised if some birds of prey home in on potential prey by sight of tracks from above but I have no evidence or examples.
  7. Unless it's a very powerful transmission, aimed at us from relatively nearby, relatively recently we probably won't notice it, not even when we are looking/listening. Much depends on what technologies they - and we - use. Intelligent with advanced technology does not automatically lead to spacefaring. Having space capability does not automaticaly mean space colonising even within a solar system. Given the distances and difficulties, intersteller travel and colonising cannot be considered likely. Those that do attempt it may be a much rarer subset of intelligent races. But if interstellar travel is achievable and if they are wise as well as intelligent - they may want to avoid notice by homo Sapiens and species like them. Surely any deliberate message we send out will - after careful consideration and composition - be misleading and deceptive; even if it's a case of accentuating the positive combined with lots of omissions - lying to ourselves as much as to them - we will probably start any dialogue with falsehoods. Not a good start.
  8. Yossi, I found this online introduction to evolution by Chris Colby worth a read. It seemed to be comprehensive and informative - http://www.talkorigins.org/faqs/faq-intro-to-biology.html
  9. Mistermack - currently more capacity of renewables are being built than nuclear and coal combined and the price point where they are cost effective has recently been passed. Cost estimates for new RE projects keep going lower. Intermittency is an issue but it isn't insurmountable and can actually become a defacto carbon price by forcing fossil fuel plant into greater intermittency, increasing incentives for solution. The PV and battery combination is just reaching the point here where it's use makes our household power bill cheaper - not 100% supply of course but forcing coal and gas into the role of backup and used more intermittently, in smaller amounts, rather than continuously is a step we can make and should make using the technology we have. Doing so will create economic incentives that favour investment in storage technologies.There are soundly based projections of battery costs coming down a lot - from very close to economically viable now to become economically sensible over the next few years. I struggle to understand why fusion, with extraordinary technological hurdles to overcome, that has such a poor record is held up as a potential saviour whilst renewable energy that has such a good record of successful, rapid improvement is - still - treated like it can't ever overcome it's limitations. Fission using proven nuclear technology will surely have a role however it's problems remain principally economic ones (and political ones that derive mostly from the economic ones) - renewable energy may not be a complete solution at low enough cost yet but it can and is being deployed in ever growing amounts even within the mire of conflicted climate and energy politics; as long as that mire persists nuclear, which requires strong, clear, persistent policy far more than renewables do, will be the loser. Nuclear needs a greater minimum threshold of support than renewables and the largest base of existing support can't be used effectively because of it's overlap with anti-climate action politics. Climate science denial prevents that clear, strong policy and did what the anti-nuclear activists could never do - got the captains of commerce and industry, that would be nuclear's most potent backers, to give up on serious climate action and give fixing it with nuclear a collective shrug. That was an economic decision - not fixing emissions appeared to be cheaper - not a position arrived at by assessing the validity of climate science but by assessing the impacts of addressing the problem on their near term costs and profitability. Climate science denial is justification and excuse for that position, propped up with a strong dose of alarmist economic fear. Even if climate change appears intractable to such "leaders" the choice of obstructing strong policy and avoiding a burden of climate responsibility has been within their power, using a well developed toolkit - judicious donating, lobbying, PR, advertising, tankthink. Perhaps disconnecting the collective lobbying of commerce and industry from obstruction of climate policy, by disarming the economic fear, will be the most significant thing that low cost renewable energy (even with intermittency) can deliver in the near term. That political shift may give nuclear a belated kickstart from people with great influence but solar and wind are already cost effective part of the time and storage is on the cusp of cost effectiveness; nuclear will not be competing hour by hour with solar and wind, but with hydro storage and batteries during the combined wind lows and evenings. The whole of RE system's success in emissions terms will come more slowly, as existing emitting plant displaced and shut down, but I think there is reasonable expectation that it will. Millions (billions) wasted on capture schemes - true. Including dubious reforestation schemes that simply cannot make a significant difference if the fossil fuel burning continues. As long as the area dedicated to reforestation is less than the preceding deforestation it will struggle to sequester the carbon released by that deforestation. It does not store endlessly - it becomes part of the carbon cycle - it will reach a point where it releases as much as it stores, well short of sequestering what fossil fuel burning releases.
  10. Forests will never be able to fix much more carbon than was released by prior deforestation; it is unrealistic to expect it to sequester the far greater additional carbon from continued fossil fuel burning as well. Since the land that hosted the greatest forests are where the best soils and greatest amount of agricultural production is occurring it will not be re-planted. Reforestation will also face problems and risks due to climate change including greater risks of limited growth and tree deaths from things like drought, heatwave, fire. There is no certainty such forests will survive over the long term let alone permanently store excess carbon. There are good and sound reasons to encourage reforestation where possible but it won't work as a means of avoiding the real solution - which is making the energy we use with minimal or zero emissions. Given what is known about climate and climate change dangerous and irreversible climate change will result long before fossil fuels run out. There is no danger of an imminent ice age even if AMOC shutdown could result in decades of strong regional cooling - and no certainty that nuclear fusion energy will ever be reliable, abundant or cheap. Climate action requires more urgent and effective actions than reforestation. Innovation will be essential and we will probably never have the comfort of certainty of means, costs or effectiveness for a full climate solution but the starting point is where we are now. I think we do have what we need to make a serious start on emissions reduction.
  11. If we reach the point where fossil fuels are running out, rather than being left in situ because we are using low emissions energy alternatives then we are going to be in serious trouble. As a solution to our current and accumulating climate problem fusion isn't a viable option and if it's as extremely difficult to do as seems apparent the likelihood it will become a cheap, mass produced, reliable and ubiquitous energy technology is doubtful.
  12. EdEarl, although I am very optimistic that crucial limitations of energy storage can be overcome I'm a bit wary of predictions of rates of battery improvements - it's going to be dependent on the actual tech developments feeding into the commercialisation pipeline rather than extrapolation based on observed rates of change. Some costs can be expected to come down in the near term due to improvements in manufacturing methods and economies of scale, including because of automation and I think we can see that with Tesla. These tend to be improvements that reduce the costs of existing and incrementally improving technologies but I suspect there will be diminishing returns over time; the most significant innovations, the real game changers - such as major improvements in energy density that commercial electric aircraft would require - are going to remain unpredictable.
  13. I would like to believe we have that kind of battery technology in the near future and I can see it's heading in the right direction. I'm not convinced it is truly assured any time soon at the scales and relative costs needed, especially not without firm, appropriate energy policy applied with great conviction - or the absence of inappropriate energy policy applied with great conviction. Nor do I think massive growth of robotics can occur without adding it's own environmental and economic burdens; they may have some potential to tackle some difficult problems but too many of the most critical problems are not presenting themselves as profit making opportunities. The political fallout of ever greater loss of employment opportunities to automation might be ever greater support flowing to the kinds of populist political opportunism that prevents foresight and planning being applied in a thoughtful and far-sighted manner.
  14. EdEarl, I think that without the low emissions energy technologies underpinning their production and use, robots will just add to rather than reduce the emissions problems. Automation/robotics will undoubtedly play a role in making those improved energy techologies at the scales needed but the emissions problem will only be solved by addressing the emissions problem, not by cleaning up the mess it makes afterwards.
  15. Unless sequestering CO2 is a low cost consequence of profitable kelp farming for other reasons it's no more than one more thought bubble. There may be sound reasons for activities that increase biosequestration - increased soil carbon, re-forestation - but I can't see how they can put enough Carbon back into sinks and stores to replace what clearing and agriculture took out let alone all the extra from excessive fossil fuel burning. That we are failing to do so in a prompt and adequate manner doesn't alter the clear imperative to drastically reduce that rate of burning and if we continue to fail no amount of kelp farming or biochar will prevent serious and irreversible climate change.
  16. Seeking to attribute short term variability to specific climate processes - and 15 years is short term - is reasonable. (The largest component of that variability has been ENSO, an ocean oscillation between warm water accumulating at and near the surface that warms the air masses over it and warm surface water being forced deeper and being displaced by upwelling colder water that cools the atmosphere). Calling it a pause in the rate of global warming is not so reasonable; ocean heat content which more directly measures the underlying changes from AGW continued to rise during that period, without any such pause. Whilst scientists may have attempted to explain what they mean by "pause" (a period of surface temperature variability) it was wrongly interpreted as some kind of admission that warming stopped during this period. With climate science so politicised it's unfortunate that choice of terminology can be so significant. Calling it a "pause" was a mistake and helped perpetuate the illusion that GHG driven AGW is something erratic, that comes and goes rather than being a persistent underlying influence which is overlayed by natural and unnatural variability. Temperatures adjusted for known influence of El Nino Southern Oscillation (with no change to long term trend) - Ocean Heat Content - Global warming didn't pause or stop at all.
  17. I think it's a far greater problem that so many people who are educated and intelligent choose where to stand on climate and emissions according to criteria that have nothing to do with the validity of the science based advice. That so many in positions of power and influence lend respectability to denial of the problem's seriousness and to opposition appropriate policy responses to the expert advice is a more profound failure of trust and responsibility than "ordinary" people making the best of their own circumstances and opportunities in ignorance of the wider consequences. I suspect a great many of those "leaders" are aware of the importance, but that it is less immediately important to them and the organisations they lead than avoiding the burden of costs and complications of having to commit to a society wide remake of how we make and use energy.
  18. It would be good if Patti would follow up her opinion that global warming is merely opinion with something. Preferably something more than more opinion. That she (I'm assuming she) has started with a provocative statement doesn't concern me - some good discussions start that way - but some reasons why she holds that view would go some way to directing the discussion into realms of greater relevancy. Sounds suggestive of a philosophical "how can science know what it knows" objection but I don't know.
  19. Haven't we already had 1 degree of warming and not yet reached a doubling of CO2? And the transient response - near term change we are experiencing - is going to be short of the ultimate equilibrium response - long term change.
  20. If fossil fuels had been scarce resources would we have had an industrial revolution? Not as it played out historically but I suspect we would still have achieved a lot. We may have valued their products - and the alternatives like steel making from charcoal - more, without the option of taking them for granted and whilst perhaps the consumer economy with it's growth in prosperity as well as extravagant wastefulness may have been harder to achieve economic growth and innovation would not have stopped. Would we truly be less capable of lifting ourselves out of poverty or would there have been earlier and greater incentives to manage our economic activities within the bounds imposed? Greater use of wind, hydro and solar seems obvious but forest farming - for timber, firewood, blacksmith's charcoal, chemical feedstocks - less obvious from our perspective, could have looked crucial and become more important. All these technologies would have been economically important and subject to ongoing innovation at a greater rate because of it. Still, the impacts would likely play out in more than just the technologies we rely on - pace and type of social change, governance, warfare, academic and ideological thinking...
  21. The simplest and most compelling explanation for how the Egyptians moved blocks of stone I have come across is lashing crescent shaped timbers around the blocks and rolling them. The doco I saw claimed such pieces - flat on one side (chord of a circle) and a section of circle circumference on the other and with a deep slot carved around it for ropes - were found in burial chambers but their function was not recognised. 8 such pieces would effectively lash two wheels around each block which could be rolled with relatively ease and would be reusable for similar sized blocks. I think a variant of this with 4 pieces that cradle the block rather than 8 was excavated. Even going up ramps would be relatively uncomplicated - I'd hesitate to say "easy" - I'd probably wrap ropes around and have teams pull, with people with blocking wedges keeping pace behind. Even so I doubt only one method was in use - depending on what size, shape and fragility of what needed to be moved, and the terrain, other methods probably had their place.
  22. This isn't entirely clear to me but.. It sounds like a distrust of uncertain or incomplete knowledge - with science based knowledge acknowledged to be incomplete and retaining degrees of uncertainty. Yet alternatives like religious beliefs might claim absolute certainty and completeness whilst rejecting the requirement for evidence of that being so - and may include the dogmatic rejection of contrary evidence because being contrary is taken as evidence that it is false. Whilst uncertainty allows for knowledge to be tested, changed and improved, absolute certainty resists improvement. The amount of uncertainty within science based knowledge can vary widely, from so near to certain as to be for practical purposes indistinguishable from it to very uncertain hypotheses that can exist as allowable possibilities within the bounds of what is known yet to be confirmed or rejected; what may be unique to science is embracing that uncertainty and making it into motivation to further test and refine knowledge. I'm wary of any absolute definitions of what science is or how it is undertaken; I suspect even those are subject to change in the face of changing methodologies and human needs. Even so there are some common, unifying threads including accuracy of observation, measurement and record keeping, the requirement for reasoning to be logical, the making available of data and reasoning to peers for critique, review and replication.
  23. To what extent is "But I didn't know" acceptable when reports and advice from the leading science advisory bodies - like NAS or Royal Society - is consistent? I have begun to suspect the main value of the handful of credentialed climate scientists who reject the science of their peers isn't to persuade the public it is to provide a reasonable seeming excuse for those who should know better and hold positions of trust and responsibility to assist in avoidance of that responsibility and potential liability. Of course having elected governments - politicians being effectively immune from legal redress no matter how irresponsible - who are sympathetic to those seeking to avoid the burden of climate responsibility can short circuit any attempts to use the legal system to enforce the "acting in good faith" and other requirements.
  24. Waitforufo - it sounds like you have a combination of exaggerated economic fear of fixing the climate problem and understated economic fear of not fixing the climate problem. The studies like Stern and Garnaut lend support to the view - supported by climate science - that there is much more to fear from the latter. Like borrowing big and living high ("being Great again"), the economic benefits of avoiding a transition to low emissions come with a heavy debt that is going to be paid; I'm not sure it's anything to be proud of that most of that will be paid by others ("putting our nation (or our generations?) first"), most of whom will have gotten little or none of the benefits. That debt is going to be paid out irreplaceable natural capital - upon which essential economic activities depend - constraining future economic potential in ways that are irreversible.
  25. Whether it's dodging significant questions they would prefer not to answer - and on climate that's what our conservative Australian politicians do as standard - or those diverting accusations that shift the focus away, being misleading and deceptive is a significant political skill. It doesn't benefit those who lie the most, but those who lie - or fail to tell the truth - selectively and intelligently. For climate that can be building perceptions of it being of low significance, or low priority or that it is more difficult and economically damaging to address (using alarmist economic fear) than it actually is. I suppose sometimes they believe their own BS - ie they are failing the great trust and responsibility of their office by failing to be well informed and give proper consideration of expert advice. Ordinary citizen may have a kind of right to remain uninformed or misinformed but those who hold offices of trust, responsibility and power ordinarily do not. Politicians appear to have considerable immunity from being held legally accountable when harms arise that they could or should have been aware of - and they failed to give credence to in their decisions. They are not usually held legally accountable, rather, they are accountable to public opinion via election processes; but public opinion is mutable, influenced in ways that can have little relationship to the best available expert advice on any particular issue. News service are not strongly bound either and can and do present biased, misleading and deceptive information, often engaging in the influencing of public opinion in partisan rather than impartial ways. Politicians both reflect and influence public opinion; to seek to mislead and misinform the public about an ongoing issue the expert advice is consistent in saying is profoundly important to long term prosperity and security is, in my opinion, a very serious breach of trust. Whether they do so knowingly or because they have failed to - or are incapable of - comprehending the abundant advice available they are letting us all down by preventing the preventative measures the climate problem - which is effectively irreversible - from being addressed effectively.
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