SkepticLance

The idea that ageing is an adaptation to combat cancer makes no sense at all. If so, we would expect older people to be more cancer resistant. In fact, the reverse applies. A 75 year old has 100 times the chance of developing cancer within 12 months compared to a 25 year old. Thus, the best defense against cancer is to stay young, not grow older. You should realise, that in terms of evolutionary success, to grow old and die is not a failure. As long as reproduction occurs and the genes are passed on, that ageing and dying individual is an evolutionary success. Protecting against cancer is only an advantage if it happens in the youthful reproductive years. Ageing to provide protection is kind of pointless.

Definitely the wrong forum. I suggest you go and sign up with http://www.skepticforum.com/ Have a nice chat with like minded people. Cheers.

There are a number of theories as to why humans age. here are a few. 1. Evolution creates ageing genes to elimate maladapted individuals, so they cannot contribute their genes to the population. In a changing environment, the gene pool must change, and individuals adapted to a different environment must go. 2. The genes for ageing are harmful mutations that take effect only with greater age. Since they act long after normal reproduction has already happened, they are not eliminated by natural selection. Over a period of a billion years or more, these harmful genes have accumulated, till there are now enough to age and kill every individual in time. We already know that the rate of elimination of harmful mutations from the population depends on when they affect individuals. Genes like Progeria, which cause harm before puberty are eliminated quickly - one generation. Genes that kill after puberty, like hemophilia, take a number of generations to be totally eliminated. Genes like Huntingtons which kick in after age 40, may take 100 or more generations to be eliminated. It is reasonable to suspect that harmful genes that have an effect only after, say, age 50, may never be eliminated. 3. The mitochondria are the source of ageing. These are the energy producers of the cells, and they have their own nucleic acids, which produce their own respiratory enzymes. As time goes by, more and more mitochondria develop harmful mutations. As a higher percentage of the mitochondria in the human body become less able to produce energy, the body's processes slow down. Laboratory studies have shown that mitochondria do, in fact, suffer such defects over time. This is reversed in reproduction by a selection process. The defective mitochondria are eliminated, and only unspoiled ones can become part of a human ova. Thus, a new embryo begins with a clean slate. and so on.

Why should masturbation be selected for at all? In my view, what evolution selected for was a powerful sex drive. The human male has a portion of his brain dedicated to sex drive, and that portion is four times as big as the equivalent in the human female. Evolution selected the randy male. Because the level of randiness was too high to permit satisfaction with male/female sex every time the guy got the hots, those randy and frustrated people did the only thing that was left to them. There is no reason why the masturbation behaviour should have bee a result of evolution. It was just a side effect of evolution for strong sex drive. While females are also known to masturbate, they do it less frequently than males, and only 50% of sexually inexperienced females do it at all. However, the reason why they do it is likely to be similar to males - gaining one kind of satisfaction when the other is not available. It does not have to be the direct result of evolution - just a side effect. A comment on life span. This is totally unaffected by masturbation. Humans live a long time because of the grandparent effect. Evolution selected genes for long life span, because having grandparents assisted in the survival of the grandchildren. Thus long life span was an evolutionary advantage. Clearly, how much a young person masturbates does not affect the grandparent effect, and cannot alter evolution for life span.

To swansont If you cannot draw conclusions from strong correlations, what can you draw them from? There is one thing worse than not quantifying an effect, and that is deriving a false result from a faulty quantifying process. That appears to be what is happening with attempts to quantify solar forcings.

To swansont As I have said before, apparently to no avail, the IPCC models do NOT allow for sunspots. They have a variable built in that is called solar forcings. This appears to me to be a result of measures of solar irradiance, which is only ONE of the outcomes of sunspot activity. To my knowledge, there are four major changes during times of high sunspot activity. 1. An increase in solar irradiance. 2. An increase in solar magnetic effects. 3. An increase in the solar 'wind' - the stream of charged particles hitting the Earth, as shown by the aurora's bright displays. 4. An increase in ultra violet, which can be at least 100 times as high when sunspot activity is very high. To assume that solar forcings from irradiance is the whole story is not a good reflection of reality. Swansont said "You need to establish that the solar change indicated will actually cause a ~0.4 ºC change, as opposed to stretching a graph to make things overlap well." If you read my postings, you will see that I have made no claims for quantitative effects of sunspots. Just close correlations between sunspot activity and global temperature change. The 1910 to 1941 warming was 0.4 C, and the record indicates this warming closely correlates with sunspot activity increase. However, there may have been other influences, so I do not claim the whole 0.4 C is sunspot activity. In fact, the whole problem here is the degree of uncertainty. As I have said many times, if we do not understand the mechanism, how can we determine how much?

It is actually very straight forward. No great interpretation effort is needed. However, I expect that 1veedo and bascule will see what they want to see in those graphs. The 1976 to present portion of the graphs are pretty simple, and I have not disputed the IPCC version of climate change for that period. My opposition has only been with the time period before 1976. And for that time period, the graphs are seriously off the mark. By way of comparison, check the graph in this link. http://www.mps.mpg.de/images/projekte/sun-climate/climate.gif This shows the effect of sunspot activity on global temperature change. Look at the portion of the graph before 1976, and compare it to the same portion of the equivalent graph as posted by bascule. For bascule's graphs, look at the pink portion compared to the dark line. The blue portion is just a distraction in terms of this discussion. If you are honest with yourself, you must admit that the sunspot activity in the graph in my link more closely correlates with actual temperature than the model's predictions in bascules graph. Thus, the IPCC models do not approximate reality for that time period, as well as a prediction based on sunspots.

To bascule. A very nice set of graphs. Thank you for posting them. They pretty much demonstrate what I have been saying all along. That is that climate projections and the correlation with greenhouse gases have been OK since 1976, but start falling apart earlier than that. If you look at the graphs, and screen off with your hand the area to the right of the 1976 portion, the simulations are not terribly impressive. In some cases, such as the global ocean, they are distinctly incorrect. If you wish to challenge my assertions using those graphs, you have to look only at the pre-1976 portions. As I said earlier, getting it right after 1976 does not even need a computer model. And if you go back even earlier, the level of accuracy tumbles. The reason is simple. As I said all along, where sunspot activity becomes important, the models cannot account for it. However, bascule, you should realise that I am not actually challenging your main belief. It is the portion after 1976 which bears out the fact that humans are changing climate, and shows that we should start dealing with that problem. What happened before that is actually irrelevent.

To iNow First : about models passing every test. Not so. The models predict current temperature change quite adequately. Hey, I can do that by mental arithmetic. The world is warming at the rate of 0.16 to 0.2 C per decade. How much will it warm in the next 25 years? I think I can work it out. On other matters, such as the frequency of storms, which areas are becoming more or less arid etc. Sorry. The models sometimes get it right, and sometimes get it wrong. For example : the models predicted mainland Antarctica would be warming. It is, in fact, cooling. And the models have no show at all at predicting anything that depends on off Earth phenomena, which of course relates to exceptional changes in sunspot activity. That is, changes that do not fit into the 11 and 22 year cycles. The models could not have predicted in advance the Little Ice Age, for example, since the Maunder Minimum was not predictable. On gravity. I can predict its effects also, very easily. Mostly it is quite calculable using Isaac Newton's formula, which is very simple. Climate is quite different, since it is based on a million different variables, some of which may still be unknown, some of which are estimated, some of which are based on assumptions, and some have significant known error factors. The simple fact that the IPCC values for solar forcings do not tally with the known historical impact of sunspot activity should be enough to tell you just how much to trust their calculations.

iNow said "Models don't generally discover things." I suspect your view of models is fairly close to mine. They can be useful tools, but ultimately science depends on objective and empirical data. The conclusions of models must, like any hypothesis, be tested. This is done through prediction, and an attempt to disprove the prediction, using real world experiment or observation of a novel kind. However, Bascule does not seem to need those models to be tested. Instead, the mere assertion that they come from IPCC is enough. The rationalisation for this is that most climate scientists agree. There was another incident in recent science that shows how poor an argument this is. For most of the 20th Century, medical science believed that stomach ulcers were caused by excess acid. This was backed up by the fact that anti-acids and similar medication relieved the symptoms. The consensus of medical science was solid. Then some researchers found a bacterium associated with ulcers - Helicobacter pylori. They carried out a little lateral thinking and wondered if this bacterium might cause ulcers. They tested the hypothesis. Prediction : If the bacterium causes ulcers, then killing the bacteria should permit ulcers to heal. They used antibiotics to do this, and found the ulcers did heal. In fact they applied all of Koch's Postulates to the issue, and ticked off each one. This is supposedly definitive proof, or as near to it as science permits. Yet the consensus remained, and it took over another decade before medicine as a body came around. My conclusion: Consensus as such is meaningless. Human intellectual inertia often reigns supreme. I have pointed out to bascule repeatedly, that the solar forcings calculations he has so much faith in, cannot be reliable, since the mechanism by which sunspot activity influences global temperature is not properly understood. If you do not understand how something works, how can you calculate its effect? Clearly you cannot.

Bascule said : "If GCMs are as error prone as you seem to be alleging, how is it they've managed to reconstruct the historical record so accurately?" I would be interested to know which part of the historical record you thing were 'so accurately' reconstructed. The last 30 years are easy. That can be reconstructed pretty well with a pen, ruler, and graph paper. Before that, the modellers have been struggling, re-doing models many times to try to get it right. The historical climate record, or course, goes back to Roman times. Are you suggesting that climate modellers can reconstruct it back that far? Not without better references to sunspot effects, they cannot. "And as I said, they calculate the margin of error..." How can anyone calculate margin of error when they do not actually know what the errors are? You can calculate known errors, sure. However, it is pretty arrogant to assume that all factors are known. You are completely out of touch with reality if you think that climate models do not account for the effects of clouds. Then why have several international conferences on climate modelling discussed this problem, as a problem? In fact modeling is how many feedback loops have been discovered. This statement is utter garbage. In science, it is empirical studies that lead to discoveries such as feed-back loops. Modelling is just a tool, which raises questions that have to be tested empirically. I am not suggesting that models have no value. Like any scientific tool, they can be very valuable. However, we need to be aware of their limits. For example : It is known that phytoplankton release dimethyl sulphide, much of which enters the atmosphere, and forms nucleation centres for cloud formation. Satellite studies show that there is extra cloud formation over parts of the ocean with a high chlorophyll count. ie. where there are a lot of phytoplankton. Warmer oceans lead to more phytoplankton growth, thus more clouds, thus more cooling. This is a simple negative feed-back. Would you care to tell me how a computer model could have discovered this?

To DrDNA Yes, I am familiar with that argument. However, we do not actually know the conditions under which biogenesis occurred. The idea that it was in a high temperature thermal situation is one of a number of speculations. I have seen other ideas expressed. Until we have much greater understanding of the required conditions for biogenesis, should we not refrain from excessive speculation about life appearing on places such as Enceladus?

As a for instance. Recent data from the space probe Cassini shows that the moon of Saturn called Enceladus has a certain geyser activity. There is a possibility that liquid water may be a part of the geyser action. Of course, they may be wrong. However, there is immediately a raft of speculation about maybe finding life on Enceladus. I have no doubt, that if we found liquid water on one of Saturn's moons, and injected a million randomely chosen species of Earth bacteria and Archaeans into that liquid water, a tiny minority would actually adapt, and eventually reproduce and evolve in that new habitat. However, these are organisms with 3 billion plus years of evolution behind them. What is the possibility that an indigenous life form may have come into being, through whatever biogenesis process, on the moon itself?

One of the arguments I have encountered in relation to life on other worlds relates to extremophiles. Extremophiles are organisms that live in extreme environments - usually bacteria or archaeans. They may be found in hot thermal vents, extreme pressures, extreme cold, extreme pH limits, extreme salinities, or even at extreme depths under the Earth's crust. The argument is that, if life on Earth can live in such extreme conditions, then we can expect it to be widespread on other planets, under those extreme conditions. Life on Earth seems to be able to survive anywhere there is liquid water. Can life be found on other worlds anywhere there is liquid water? There seems to me to be a major flaw in these arguments. While life may survive today, after 3 billion years of adaptive evolution, in these extreme environments, would life actually begin in those places? Can biogenesis occur in a range of extreme environments on other worlds? Any views?

A small point about cruelty on farms. Animals that are raised in conditions of sickness, stress, hunger, pain etc., will fail to put on weight. Dairy cows will fail to produce much milk. Those farms will be less productive and will lose money. Animals that are treated cruelly at time of slaughter will be stressed, and this translates into tough and poor tasting meat. It is financially advantageous for both farmers and slaughterhouse operators to treat animals well. They make more money that way. Sure, there are still people who treat animals cruelly. However, for meat animals, the money incentive is towards treating them well. Thus, the majority of farmers do what they can towards their animals welfare.

To DrDNA Not really. Tar in a smokers lungs will be very wet. Dry flammable clothing seems to me to be a better bet, especially if splashed with something flammable like a spirit.

To DrDNA I am sure you are correct. A flame is a better source of ignition than a spark, and smokers do 'play' with fire a lot. Hot burning clothes may be hot enough to ignite body fat.

To 1veedo to suggest that the sun is not causing global warming as a blanket statement is a bit moot. While I agree that is not the case right now, and has not been for 30 years, surely you must agree, at the very least, that changes in sunspot activity have been a part of the total picture over the 1000 years before? As I said, repeatedly, and gave references to support, sunspot activity increased before global temperature increase, and dropped before global cooling on a number of occasions over that 1000 year period. This is as close in science to cast iron 'proof' as we can get that it is a powerful influence. If it were less than a dominant influence, we would expect temperature to go up and down independently of sunspot activity change over that time, as more dominant influences exerted their influence. This has not happened. If your statement that the sun does not cause global warming refers only to the present situation, I agree with you (even though the statement is technically incorrect. With no sun there is no warming, by definition. However, I assume you were referring to changes in sunspot activity.). If it is meant to refer to most of the last few centuries, then I have to say that is not correct.

Some years ago I spent a weekend in Las Vagas. Now that is a weird city! And that's not even taking the people into consideration. It was built in the middle of the desert, and the air is really dry. I found myself walking down the corridors in my hotel with my fingers sliding along the wall to discharge myself. If I walked along the carpets without touching the walls, the static built up, and every time I reached for a door handle, I got a belt. If you are in a dry area, static electricity builds up, and can carry quite a jolt. Imagine spilling some flammable whiskey on your shirt, just before the spark. Not beyond belief that it would ignite.

Seems to me there are two issues here, and they are getting mixed up. 1. Cruelty to animals 2. The morality of eating meat. On issue 1, I bet we could quickly get consensus from all those contributing to this thread. Do we all oppose cruelty to animals? I bet we do. There will be farms that let their standards lapse. I know of a couple of battery chicken farms that definitely should be closed down. The way they keep their animals is a crime. I suspect that everyone on this thread would agree with me. Farmers who do not care properly for their animals, and allow them to suffer, well - they are criminals and should be shut down. Anyone disagree? However, issue 2 is quite different. If animals are well cared for, and permitted to live a life that is longer on average than they could live in the wild, less stressful, and healthier, and then killed painlessly and without stress - then what is the moral dilemma? Those animals will live better lives than otherwise can be expected.

Life span is subjective. It's not the years that count. It's how long it feels. And for a married man, life seems to be very long indeed. (Just joking)

If that's a step in human evolution, it is a very short one. And at the far end of the step is a 50 story fall! Spontaneous combustion seems to be something that happens to fat people. Not surprising, since fat tissue is the most flammable. To go from a simple clothing fire to a person burning requires a very high ignition temperature and a good source of fuel - fat. I doubt that we could call it a survival trait!

I was raised on a dairy farm, and I know damn well that those cows had a pretty good life. We, the farm workers, busted our guts in work to make sure the fields grew thick, juicy green grass for them. We removed any toxic weeds from the fields that might harm them, and carefully planted grass seeds of the varieties that were most nourishing, fertilising the fields to keep it growing well. We fed them hay and silage in winter when the feed was poor, and worked really hard in summer to prepare that hay and silage. Any sick cow, and the vet was called. I often felt that the cows had a better life than we humans did.

To Bascule I think it would take a calculator to count the number of times you have accused me or someone else of straw man arguments. What do you think you are doing when you argue against something I never said ? When a climate scientist uses the results of calculations to make more calculations to make more calculations etc., it is not some accumulated mass of arithmetic mistakes that leads to the final accumulated error. It is instead the accumulated mass of errors coming from imprecise data, and the accumulated errors coming from various inaccurate assumptions. For example : one criticism made by a variety of climate scientists is that exisitng climate models do not take into account changes in cloud formations. The assumption that is built into the models is that such formations do not affect overall climate. In fact, I have seen this written down in a report by those modellers. However, that is not a demonstrated empirical fact. It is simply an assumption, and one that is probably wrong. There are also numerous negative feeds-back mechanisms that have been proposed. While some of these ideas are probably wrong, some are probably correct. Current climate models do not take these into account, which is another source of error. Excessive complexity in computer models can be tolerated if all factors are known to great precision. This is not the case with climate models.

To Chris You obviously just jumped in onto this thread. To get you up to date, my argument has been that greenhouse gases have been the dominant driver of global warming since about 1976, but earlier than that, the correlation gets shaky. In fact, before 1976, sunspot activity correlates much better and has done for at least 1000 years into the past. I believe that there is a real confusion between solar irradiance and sunspot activity, which has other effects above and beyond simple irradiance changes. More references http://www-das.uwyo.edu/~geerts/cwx/notes/chap02/sunspots.html A quote from this paper. "Using a global climate model based on energy conservation, Lane et al (3) constructed a profile of atmospheric climate "forcing" due to combined changes in solar irradiance and emissions of greenhouse gases between 1880 and 1993. They found that the temperature variations predicted by their model accounted for up to 92% of the temperature changes actually observed over the period -- an excellent match for that period. Their results also suggest that the sensitivity of climate to the effects of solar irradiance is about 27% higher than its sensitivity to forcing by greenhouse gases. " The next reference contains an error that was later corrected. The authors overstated the number of sunspots since 1960, but their earlier estimates were pretty much correct. I am not sure why the error occurred. I doubt it was scientific dishonesty - more likely a human mistake. http://www.oar.noaa.gov/spotlite/archive/spot_sunclimate.html