Posted on 05/26/2005 10:30:32 AM PDT by xzins
I understood that DDT did have a direct influence on egg-shell thickness (ie, number of broken eggs in the nests.
(Doesn't excuse killing millions of innocent humans to preserve eggshells, but it should be noted.)
Which bites harder: a cougar or a mountain lion? ;)
In this part of the country, apparently it's shouting the following phrase:
"Hey y'all! Check this out!"
What's the difference?
Ehh??? Where have you been. The last major war over religion has been going on for 1300+ years, it's called Islam and its infectious spread.
My understanding is that almost everything in Silent Spring was junk science. That the volume of DDT in use at the time had almost zero impact on the environment. Now that I said that, I'm not sure where I read it. Perhaps in the Skeptical Environmentalist.
A voice of reason.
Total deaths resulting have been trivial compared to those of Communism and Fascism.
Hitler killed 20 million in Russia alone, part of his plan to exterminate the slav.
But... but... They meant well, and might have saved thousands of birds.
That alone absolves them of any and all collateral damage.
I got to go meditate now.
(Not that there's anything wrong with that!)
"And hold muh beer!"
They Young Turks and Atoturk after them, butchered 1 million Orthodox Armenians, 500,000 Orthodox Assyrians and 2 million Orthodox Iotolin Greeks.
Don't forget the Turkish islamic massacres under the Young Turks and then Atoturk. Don't forget various Islamic massacres in India and SE asia. Don't forget about places like Nigeria, Ethiopia and southern Sudan (before the 1940s) or the SS muslim divisions Hitler used.
You're mistaking ethnicity for religion in many cases.
In Darfur, for example, the victims are Muslims as well as the perpetrators.
----- *** EXACTLY !! ***
I agree. We have a problem of evil in this world but the Secular Humanists will always say that if we can only educate the ideologue or the religious person then we can have peace on earth. They are also fond of saying "seek rational and reasoned answers" for our problems.
I'm not convinced - Educated barbarians will surely kill you. : D
More people have been killed in the name of God-duh than for any other reason.
DDT was alleged to have thinned bird egg shells.
Many experiments on caged-birds demonstrate that DDT and its metabolites (DDD and DDE) do not cause serious egg shell thinning, even at levels many hundreds of times greater than wild birds would ever accumulate.
[Cecil, HC et al. 1971. Poultry Science 50: 656-659 (No effects of DDT or DDE, if adequate calcium is in diet); Chang, ES & ELR Stokstad. 1975. Poultry Science 54: 3-10 1975. (No effects of DDT on shells); Edwards, JG. 1971. Chem Eng News p. 6 & 59 (August 16, 1971) (Summary of egg shell- thinning and refutations presented revealing all data); Hazeltine, WE. 1974. Statement and affidavit, EPA Hearings on Tussock Moth Control, Portland Oregon, p. 9 (January 14, 1974); Jeffries, DJ. 1969. J Wildlife Management 32: 441-456 (Shells 7 percent thicker after two years on DDT diet); Robson, WA et al. 1976. Poultry Science 55:2222- 2227; Scott, ML et al. 1975. Poultry Science 54: 350-368 (Egg production, hatchability and shell quality depend on calcium, and are not effected by DDT and its metabolites); Spears, G & P. Waibel. 1972. Minn. Science 28(3):4-5; Tucker, RK & HA Haegele. 1970. Bull Environ Contam. Toxicol 5:191-194 (Neither egg weight nor shell thickness affected by 300 parts per million DDT in daily diet);Edwards, JG. 1973. Statement and affidavit, U.S. Senate Committee on Agriculture, 24 pages, October 24, 1973; Poult Sci 1979 Nov;58(6):1432-49 ("There was no correlation between concentrations of pesticides and egg shell thinning].") ]
Experiments associating DDT with egg shell thinning involve doses much higher than would ever be encountered in the wild.
[J Toxicol Environ Health 1977 Nov;3(4):699-704 (50 ppm for 6 months); Arch Environ Contam Toxicol 1978;7(3):359-67 ("acute" doses); Acta Pharmacol Toxicol (Copenh) 1982 Feb;50(2):121-9 (40 mg/kg/day for 45 days); Fed Proc 1977 May;36(6):1888-93 ("In well-controlled experiments using white leghorn chickens and Japanese quail, dietary PCBs, DDT and related compounds produced no detrimental effects on eggshell quality. ... no detrimental effects on eggshell quality, egg production or hatchability were found with ... DDT up to 100 ppm)]
Laboratory egg shell thinning required massive doses of DDE far in excess of anything expected in nature, and massive laboratory doses produce much less thinning than is seen in many of the thin-shelled eggs collected in the wild.
[Hazeltine, WE. 1974. Statement and affidavit, EPA Hearings on Tussock Moth Control, Portland Oregon, p. 9 (January 14, 1974)]
Years of carefully controlled feeding experiments involving levels of DDT as high as present in most wild birds resulted in no tremors, mortality, thinning of egg shells nor reproductive interference.
[Scott, ML et al. 1975. Poultry Science 54: 350-368 (Egg production, hatch ability and shell quality depend on calcium, and are not effected by DDT and its metabolites)] Egg shell thinning is not correlated with pesticide residues.
[Krantz WC. 1970 (No correlation between shell-thinning and pesticide residues in eggs) Pesticide Monitoring J 4(3): 136-141; Postupalsky, S. 1971. Canadian Wildlife Service manuscript, April 8, 1971 (No correlation between shell-thinning and DDE in eggs of bald eagles and cormorants); Anon. 1970. Oregon State University Health Sciences Conference, Annual report, p. 94. (Lowest DDT residues associated with thinnest shells in Cooper's hawk, sharp-shinned hawk and goshawk); Claus G and K Bolander. 1977. Ecological Sanity, David McKay Co., N.Y., p. 461. (Feeding thyreprotein causes hens to lay lighter eggs, with heavier, thicker shells)]
Among brown pelican egg shells examined there was no correlation between DDT residue and shell thickness.
[Switzer, B. 1972. Consolidated EPA hearings, Transcript pp. 8212-8336; and Hazeltine, WE. 1972. Why pelican eggshells are thin. Nature 239: 410-412] Egg shells of red-tailed hawks were reported to be six percent thicker during years of heavy DDT usage than just before DDT use began. Golden eagle egg shells were 5 percent thicker than those produced before DDT use.
[Hickey, JJ and DW Anderson. 1968. Science 162: 271-273]
You are so kind! :>)
As you'll note from my tagline, I'm a retired Army chaplain.
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