SkepticLance

Lemmings! Let's nail at least one myth. Lemmings do NOT commit suicide (except in movies by Walt Disney). The Great Lemming Suicide is an urban myth, even if it is set in the wilderness. Lemmings undergo periodic population explosions. When that happens, the death rate increases dramatically, but due to increased predation, lack of food etc. NOT suicide.

herpguy, As someone who has followed my postings in the debate, and also in other threads, you should realise by now that I am not asserting either side of the argument. My position is simply that no-one knows. In fact, I think it is somewhat arrogant to push too strongly one view or the other. In short, we simply do not have enough hard data to say that it is proved that human activity is the dominant driver of global warming. On the other hand, we cannot say too certainly that it is due to natural forces. My private view (unproved) is that global warming is driven by a number of factors, of which human release of greenhouse gases is just one. Of course, I could be wrong. We need data, one way or the other. I have been reading arguments for and against for about ten years. The question I always ask is : "Where is the empirical evidence?" In this, I am quite constant in my approach.

Kylonicus. It would appear that you are guilty of an error of interpretation. Social security is only a symptom of an underlying principle leading to lower population growth. That is, empowerment of women. In this case, to give women the power of control over their own fertility. Yes, it coincides with times of improving social security and increasing prosperity. However, there is now substantial evidence of reducing population growth in places where such social security has not happened, but where contraception is made available. Does not work, of course, when women are not permitted to use said contraception. Think about it. Bearing children is bloody stressful! Very few women want to do it more than 2 or 3 times. Give them the power of control, and population growth drops.

It is seriously unlikely that we will ever get enough dinosaur DNA for a clone. However, I see no reason why someone in the future could not design an imitation dinosaur. A lot of dinosaur DNA will still live on in dinosaur descendents (birds). It is not beyond our imagination to suggest that, in the future, the genetic differences required to create said dinosaur could not be designed 'from scratch' by our future gene science, probably aided by computers.

alt F13 If I am making false assumptions, please correct them. As I see it, life MUST conform to certain characteristics. 1. It must be able to replicate its pattern, in a way similar to DNA. 2. It must be able to manufacture structural molecules in a manner analogous to proteins. 3. It must be able to vary in its set of instructions (genetic material) and have the poorer versions eliminated, permitting evolution. 4. In a sequel to condition 3, it must have the potential to form literally billions of different complex molecules, or else evolution has no base. Carbon compounds can do all the above, but sulfur????????

bascule. I have read the IPCC report. It is chock full of data on global warming, but has precious little on evidence that the dominant driver is anthropogenic greenhouse gases. Have you any such empirical evidence?

Sulfur based life forms would appear to be horribly unlikely, since sulfur does not have the versatility of carbon. Simply forming a few polymers is not enough. To begin with, some equivalent to DNA would be needed, and I do not believe any sulfur compound does this. Ditto a range of enzyme equivalents. On the other hand, carbon is so versatile that alien life forms based on carbon could be found in a wide range of environments.

bascule We have had this discussion before. As you know, I am not prepared to accept computer models in place of empirical evidence. Models have proved fallaceous in non climate situations numerous times, when variables not taken account of exert their influence. It may well be the case with climate models also. Also, the proper practise of science requires empirical evidence. We do not have to experiment on spare planets. Lots of other possibilities exist. Let me ask again. Can you supply strong empirical evidence to show that human activity is the dominant driver of global warming? The other day I was reviewing an article in a back issue of New Scientist. 27 August 2005. The subject was shrinking glaciers. They included a graph of the average shrinking of 169 glaciers world wide. The graph showed steady shrinkage from about 1810 to 2000 AD. Since greenhouse gases have increased very little before 1910 AD, the first half of the graph was clearly warming caused by something other than anthropogenic greenhouse gases. Yet, the graph shows no difference in shrinkage rate after that. It makes me a bit skeptical of the idea that warming from 1810 to 1910 was 'natural', and an exact same degree of warming from 1910 to 2000 was 'unnatural'. To prove to me that something changed, I need strong empirical evidence.

I am staggered by the number of people contributing to this thread who are simply ignoring solid facts. Population growth is slowing down. Average kids per couple in the third world 50 years ago = 5 Average kids per couple in the third world today = 2.8 (and still dropping) There is simply no NEED for compulsory contraception/sterilisation. All we need to do is provide such aid to make contraception universally available, and before we know it average kids per couple in the third world will be less than 2. In fact the United Nations predicts a maximum world population of 9 billion, after which numbers will slowly fall. And this is without any extra aid. http://www.un.org/popin/ is a very extensive web site with all the data you might need to comprehend this very simple fact.

bascule. I believe you are over-impressed by computer models. Extra-ordinary claims require extra-ordinary evidence. The claim that humans are driving the entire world into substantial warming is, indeed, extra-ordinary. In science, the only evidence that is truly acceptable is Empirical. That is: real world experiments or observations. Processes of logic and computer models do not qualify. Computer models certainly have their place, and can be invaluable research tools. However, like any scientific hypothesis, they must be backed up by empirical evidence. In the case of human driven global warming, the empirical evidence required must be very solid and very convincing. bascule, can you supply such evidence? And I don't mean evidence of warming. We all know that is happening.

reor When someone is hungry, and sees his/her children dying of malnutrition, their special way of life rather lacks priority. Lets give people the ability to feed their children first. After that, we can worry about cultural heritage.

ecoli Try http://www.un.org/popin/functional/population.html This has a wide range of data on population statistics around the world. Check nation by nation. You will find that replacement rates have fallen. I also have a copy of a book by Jim Peron : "The Population Myth" which details a mass of such statistics. It takes a while to put it all together, but it is worth it.

Dr Dalek. You are absolutely correct. Quite small changes to a protein molecule can change its shape dramatically. And shape is all important with respect to function.

This whole idea is rendered pointless by an examination of the facts. The world is not suffering population catastrophe. Population growth is diminishing fast, to the point where some "overpopulated" countries are now struggling with an underpopulating problem. eg Japan. Wherever contraceptives are readily available, especially the pill, people (and especially women) will use them. 50 years ago, third world nations had an average of 5 offspring per couple. Today it is 2.8 and falling. There is no need to sneak contraceptives to them in the guise of food aid. Simply give them the contraceptive pill and they will use it. The real problem today is economic and political. Corrupt politics in places such as Zimbabwe leads to poverty for the ordinary people. There is no easy fix. We need to provide economic aid, but targeted in such as way as to really help. That is no easy ask. It requires local knowledge, and local people (not local governments) to implement. It requires imagination.

Kermit. Nice photo! is it an isopod? What does it taste like after barbequeing?

bjaminwood Do you not know what a load of absolute codswallop you are selling? I checked you 'rebuttal' on answersingenesis. What a load of idiocy. Do you really think that a 'missing link' will magically be exactly half way between one organism and another? Of course not. The laws of chance will place it closer to one or the other. The fact that Livoniana was closer to ancestor than descendent does not stop it being a link. Between fish and amphibians, we now have two more 'missing links'. In Scientific American; December 2005 page 80, we have a description of Acanthostega, which is dated 360 million years ago. A fish, with fish tail, and four clearly distinct legs. Since its legs were too weak to lift it out of water, it is suspected that they evolved to hold its head only above water. Since this was clearly a member of the lungfish family, the selective advantage is obvious. In addition, we have fossils of Tiktaalik, named after the Inuit district where they were found. This is clearly a fish, with limbs less well developed than Acanthostega, but with a wrist-like joint showing it could do a 'push-up'. New Scientist : 8 April 2006, page 14 The relationship to later tetrapods that are full amphibians is clear. I rechecked your earlier answer to a previous question, where you tried to discredit dendrochronology, by quoting answersingenesis where another total moron tried to say that trees can make two rings in one year, and this disproved dendrochronology dating. For your information, that is a rarity, covered by the fact that dendrochronologists test many trees, to eliminate such flukes. Tree rings have been counted back 20,000 years. Way beyond your ridiculous 'the world is no more than 10,000 years old.'

The biggest problem with string theory is that it has led to no testable predictions. In science, any hypothesis must be testable empirically with the opportunity to falsify it. Anything else is religion. This does not mean string theory is wrong. it may be right, or mainly right. However, until it is empirically tested, it remains of little value.

bascule I guess the point I was making is that global warming has come to be used as the 'explain all' mechanism, for almost anything related to climate or weather. I am sure you will agree with me when I say that is not justified, and we should be sceptical of those who so use it.

RichF The same genetic phenomenon is supposed to be the reason why people of African origin do so well at the Olympic games. It is not that Africans are 'superior'; just more diverse. With a broader normal distribution curve of athletic ability, there will be more at the top to choose from. A similar mechanism has been proposed for why humans today are taller and healthier than in Roman times etc. In times when wealth and technology were limited, so was travel. Thus, people tended to stay where they were born, and marry their neighbours. This led to a degree of inbreeding. Today, people are likely to marry people from far away. Thus, less inbreeding and better genetic spread.

bascule. Both stories quoted climatologists.

bascule. There was a time, I think about 12 years ago? when the sea ice round parts of Antarctica was shrinking. The media called it global warming. There was a second time (about 5 years ago?) when sea ice round Antarctica was expanding. This was also called global warming. Apparently warmer conditions meant warmer, moister air, and bigger snow dumps. If global warming causes sea ice explansion, and global warming causes sea ice shrinkage ......

Glass is a silicate salt. It is made by a chemical reaction between ultra pure sand (Silicon dioxide) and an alkali. Once, an impure version was made by extracting alkali from ashes, and reacting with sand. The reaction is dry, and done under extreme high temperatures, in a furnace. The result is molten glass. Why are beaches made of sand? It is due to the sorting action of waves. In fact, beaches can be made of boulders, pebbles, fine sand, coarse sand, coarse or fine mud. It all depends on the average power of the waves on that beach. It just so happens that a common type of beach has a wave action that moves sand grains up the beach, washes mud out to sea, and fails to move pebbles or boulders onto that beach.

Sorry, Tomgwyther. I have to dispute with you. What you have said is true for the cartilagenous fishes - sharks and rays. It is NOT true of most of the rest. This is because the bony fishes have a swim bladder for buoyancy control. Think of this as an internal life jacket that is inflated to give more buoyancy when needed, and deflated to give less. When such a fish is hauled on a line from the depths, the swim bladder expands, and can cause enormous damage to internal organs. If that fish is subsequently released, it often cannot swim down again, due to the high buoyancy of the inflated bladder.

Mitochondria as a cause of ageing is still a wee bit controversial. However, they appear to be, at least, part of the story. Mitochondria have their own DNA and manufacture their own enzymes, primarily to carry out the function of energy release. DNA gets slowly damaged over the years, mainly by the chemical products of oxidation, thus making the mitochondria less able to produce the vital enzymes, making them effective as the cell's 'power-house'. This is the suggested cause of ageing. There are enzymes inside our cells designed to attack the products of oxidation. Humans happen to have a hell of a lot of the main one. Thus, oxidants are neutralised very quickly. Mice have a lot less of this enzyme, and their oxidants build up much more quickly. Thus mice mitichondria are damaged much more quickly than human. Incidentally, this is also the source of the widely held belief that consuming lots of food with anti-oxidants (or anti-oxidant pills) will slow or even reverse the ageing process. The only problem with this is that there is little or no empirical evidence to support it, despite many scientists testing the idea. This has not prevented a whole bunch of people and companies from making $$$$ by selling anti-oxidants with the false claim that it will slow ageing.

With suitable hormone treatment, male breasts can be made to lactate, delivering milk via nipples. This is not truly vestigial.