Global Warming...New Report...and it ain't happy news

Haven't seen you in a while, Okie

Cheers
Cycloptichorn

Thanks blatham. Hey, if that few days affords me this much good will from the opposition, maybe I should take a leave of absence more often?

No ouiji board. Rejection of the herd instinct and keeping an open mind is often the best way to achieve best solutions to just about anything.

Maybe that's what Blatham and Cyclo is trying to get you to do? They're subtle bastards, ya know ... Seriously, welcome back.

I don't think the WHO would suggest using DDT if the they thought the results would not be better then not using DDT. No other pesticide has had the positive results against mesquito populations that DDT has had and Malaria is killing far more people then the use of DDT ever would.

Thanks blatham. Hey, if that few days affords me this much good will from the opposition, maybe I should take a leave of absence more often?

Our women even rank second after Japan in life expectancy.

parados wrote:

DDT causes shell thinning in some birds. That is a proven fact that is not disputed with any science.

According to who and what evidence?

Patuxent Science Notes

DDT and Birds of Prey

The year was 1967 and Derek Ratcliffe, a British biologist, was plotting data points on his graph. He was investigating why there were fewer peregrine falcons in Britain than in the past. His best clue came from his visits to peregrine nests, where he found that falcon eggs sometimes broke before they hatched. Now he was plotting data showing the thickness of peregrine eggshells from eggs he collected or borrowed from museums. Ratcliffe arranged the data points in order, from about 1900 to 1970. The graph showed that eggshells were variable, some thinner than most, and others thicker. This variability was expected, just as animals have different weights and heights. However, the graph showed a startling and unexpected pattern. Most of the points from 1900 to 1945 were scattered about the index value of 2. Then there was a drop in the values, and the points were scattered about an index value of 1.5.

Ratcliffe had just made a significant discovery, that after 1945 eggshells became thinner and more likely to break. He and other scientists could only guess at the reason for the thinning. One suggested cause was the insecticides that were being used to control mosquitos or to control insects attacking crops. But before we can evaluate this hypothesis, we need to know a little about the biology of the peregrine falcon and its relatives, the other raptors.

Raptors are an awesome group, known for their hooked bills and powerful talons (claws), designed for ripping flesh from carcasses. They are also known as birds of prey. Raptors have excellent eyesight for locating prey from a distance. Some raptors, such as eagles, have huge wings to carry them long distances. Eagles "soar," which means they stay aloft on rising hot air currents, barely moving their wings. Other raptors, such as peregrines, can streamline their bodies as they fall from the sky, reaching fearsome speeds of up to 200 mph as they strike their prey. Because falcons are so skillful and can be taught to return to their masters, falconry became a sport popular with kings. Owls, another group of raptors, are nocturnal and have excellent night vision. Vultures are definitely the ne'er-do-wells of the group. They have shaved heads, a serious attitude problem, and the worst breath in the animal kingdom. They wander the hood, looking for carcasses, reciting their motto, "seize the prey." But enough said of these rank under-achievers. Let's get back to insecticides, but remember that raptors are either predators or scavengers. This is a clue to why they would be susceptible to poisoning.

When DDT or another insecticide is sprayed on insects, some of the residue is eaten by the predators of those animals. Those predators are in turn eaten by larger predators. This sequence is called a food chain. Animals at the top of the food chain, such as raptors, are exposed to the most DDT. At each step the amount of DDT eaten is increased, and so we call the process biomagnification. ("Magnify" means to make bigger and "bio" means life or living organisms.) Of the many animals exposed to DDT, the raptors or other predators at the top of a food chain are the animals most likely to be affected.

The suggestion that DDT was causing the decline of bird populations made sense to some biologists. However, scientists do not accept a hypothesis just because it sounds reasonable. Scientists want evidence from a controlled study. After all, it was possible that the use of insecticides and the decline of falcon populations was a coincidence, and that some other environmental factor was the real culprit. Conclusive studies were done on ducks at the Patuxent Wildlife Research Center and on kestrels at the Cornell University Laboratory of Ornithology. In both experiments, the birds were divided into two groups, the "control" and "treated." The two groups were handled the same, except that a small amount of DDT was added to the diet of the treated group. Once the two groups had laid enough eggs for comparison, biologists measured the thicknesses of the eggshells and calculated an average for the treated birds and an average for the controls. The biologists found that birds treated with DDT laid eggs having thinner shells.

These two controlled experiments proved that DDT could thin eggshells. The last step was to prove that DDT had thinned eggshells of peregrine falcons or other wild birds. A different kind of data was required to tell us about wild birds. Biologists returned to the nests of wild birds, collected eggs, measured eggshell thickness, and analyzed the eggs for DDT. From the controlled studies mentioned, biologists knew how much DDT would cause eggshells to become thin. Biologists found even higher concentrations in eggs of wild birds. They also found that the eggs with the thinnest eggshells were those with the most DDT. Finally, when the results of all of the studies were combined, Derek Ratcliffe's graph was explained. We now have firm scientific evidence that DDT thinned eggshells and decreased populations of peregrines as well as some other species of raptors.

Nelson Beyer
Anna Morton
Patuxent Wildlife Research Center
Albin Beyer
University of South Carolina

In addition, later research refuted the original studies that had pointed to DDT as a cause for eggshell thinning. After reassessing their findings using more modern methodology, Drs. Hickey and Anderson admitted that the egg extracts they had studied contained little or no DDT and said they were now pursuing PCBs, chemicals used as capacitor insulators, as the culprit.

Although some birds declined before DDT, they became much more abundant during the years of greatest DDT-use. But facts have not impeded the endless repetition of Carson's bird myth.

Scientists tested the popular shell-thinning hypothesis. U.S. Fish and Wildlife Service biologists fed birds for 112 days on a diet with 100 times as much DDT as they were getting from the environment. No thinning of egg shells was found. The DDT had no effect on the birds.

One experimenter, to demonstrate eggshell-thinning, fed quail a diet with DDT but containing only one-fifth of the normal amount of calcium. His experiment succeeded in producing thinner eggshells, but his deception was exposed.

Foxfyre wrote:

No ouiji board. Rejection of the herd instinct and keeping an open mind is often the best way to achieve best solutions to just about anything.

Again this illustrates you dont understand how the scientific method works. A scientific consensus is the very oppostie of "the herd instinct", and all scientists, if they hope to be taken seriously as such, keep an open mind.

The beauty of any scientific work is that it is continuously tested. Any scientist keen to make a name for him/herself tries to make observations that dont fit the old theory, and then goes on to devise a new theory that better describes reality.

okie wrote:

Quote:

Thanks blatham. Hey, if that few days affords me this much good will from the opposition, maybe I should take a leave of absence more often?

Another year longer away and I might have asked to have your baby.

But in either case, the goodwill is/would be sincere.

blatham wrote:

okie wrote:

Quote:

Thanks blatham. Hey, if that few days affords me this much good will from the opposition, maybe I should take a leave of absence more often?

Another year longer away and I might have asked to have your baby.

But in either case, the goodwill is/would be sincere.

I have come to view your opinions as a bit weird, especially considering your red uniform, but now your comment really has me wondering about you much more seriously! Your impending offer is emphatically refused, blatham. But at least you apparently have a sense of humor, even if it is a bit different than I am accustomed to.

By the way, Thomas, thanks also for your comment.

And thanks to Minitax, who documented the myth of the eggshell thinning, contrary to Xingu's supposed proof that he posted, which of course merely consisted of old speculation that has long since been debunked. Someday, I predict we will also have the same documentation of the "sky is falling" scientific mythology we endure every day concerning global warming.

By the way, it is unseasonably cool outside right now, and I hear the snows are falling early in the Rockies.

parados wrote:

The problem is that people like Sowell and Gunga and others promote the proposed limited use as proof that the science was wrong. They do precisely what they and others try to do in the GW debate. Find a few small mistakes in the science and point to that molehill while ignoring the mountain next to it.

Can you quantify the molehill and the mountain? How many extra people died of DDT before its ban in the early 70s? And how many extra people died of Malaria because of the ban since the early 70s? Admittedly, I haven't researched this particular issue a lot, so I can't point you to data of my own. But I do have a vague recollection that your talk of "molehill" and "mountain" misrepresents the proportion of the death tolls.

Thomas wrote:

parados wrote:

The problem is that people like Sowell and Gunga and others promote the proposed limited use as proof that the science was wrong. They do precisely what they and others try to do in the GW debate. Find a few small mistakes in the science and point to that molehill while ignoring the mountain next to it.

Can you quantify the molehill and the mountain? How many extra people died of DDT before its ban in the early 70s? And how many extra people died of Malaria because of the ban since the early 70s? Admittedly, I haven't researched this particular issue a lot, so I can't point you to data of my own. But I do have a vague recollection that your talk of "molehill" and "mountain" misrepresents the proportion of the death tolls.

It would be a molehill of inconclusive science compared to the mountain of science that says something exists.

An open mind would look at the total of the science not just the small amount that disputes the mountain of research supporting it.

By the way, it is unseasonably cool outside right now, and I hear the snows are falling early in the Rockies.