© 1999 Macmillan Magazines Ltd

the 1998 figures are “a sign that it may beless difficult to slow global warming underthe Kyoto Protocol” than has been widelyassumed, and the suggestion by others thatvoluntary reductions by industry willsuffice, seem seriously complacent.Michael JeffersonThe Old Stables, Felmersham, Beds MK43 7HJ, UK

correspondence

810 NATURE | VOL 400 | 26 AUGUST 1999 | www.nature.com

Sir — When the journalist H. L. Menckenreported on the infamous Scopes trial of1925, he remarked that the hysteriasurrounding it had made a “universal joke”out of the occupants of Dayton, Tennessee,where the trial took place. Now, 74 yearslater, but only a few degrees of longituderemoved, the Kansas Board of Educationhas in its turn made a monkey of itself. Theboard has removed the requirement forschool students to have a knowledge ofevolution to pass examinations (Nature400, 697 & 701; 1999).

This might seem hilarious in today’stechnically wired society were it not for onesobering fact. Despite overwhelmingacceptance of the material benefits thatscience has brought, Americans in generalremain deeply ignorant of its basicprinciples. If such ignorance persists, it willprove devastating to the future of ourdemocracy whose citizens will increasingly

be called upon to exercise judgement on thecomplex social issues that advances inscience inevitably bring.

As an illustration in the context of theKansas decision, consider this — one of themost profound legacies of twentieth-centuryscience for the next millennium is thediscovery of the molecular structure of DNAin the 1950s. That provided the physical basisto begin to understand the processes ofevolution on a genetic and cellular scale. In afew more decades, we will probably gain theknowledge to effect and accelerate, throughdirected genetic modification, the evolutionof all life forms — including ourselves.

How we use this power, arguably themost potent ever to be possessed byhumankind, will present the greatest socialchallenge to the survival of our species sincethe first primates stood up in the bushes, or,as they might now say in Kansas, since Adamawoke in Eden. We will have taken a big bite

out of the apple of the Tree of Knowledge,surpassing even that which released thesecrets within the atomic nucleus. Whetherwe use the former to create the horror of aHuxleyan Brave New World or to enhanceour basic humanity will be strictly up to us,just as is the decision on whether to use thelatter for peaceful purposes or to bring aboutnuclear holocaust.

Thomas Jefferson, perhaps the primechampion among the founding fathers ofthe principle of separation of church andstate, envisioned an American republicgoverned by a wise and educated electorate.To place at risk for the children of Kansas thechance to obtain all the vital knowledge thatwill enable them to keep Jefferson’s dreamalive in the coming age of biologicalrevolution is both deplorable and terrifying.Paul M. GrantEPRI, 3412 Hillview Avenue, Palo Alto,California 94304-1395, USA

Kansas makes a monkey of itself

well-known widespread senile scleroticchanges, the lipid-pigmented and granulardegenerations of ganglion cells withalterations of their fibrils which Brodmannand Bielschowsky have described in detail,the fibre-formation of the glia, pigment-accumulation in the glia and thedegenerative phenomena in the vessel-wallswhich it is impossible to believe werecaused by plaques.

“These changes are found in the basalganglia, the medulla, the cerebellum andthe spinal cord, although there are noplaques at all in those sites or only isolatedones. So we have to conclude that theplaques are not the cause of senile dementiabut only an accompanying feature of senileinvolution of the central nervous system.”

The italics are Alzheimer’s and thetranslation is by Hans Förstl and RaymondLevy6. The paper was written by Alzheimerafter his examination of only three patientswith the disease. It is a remarkabletestament to his meticulous work andoriginality of thought that 88 years ago heput forward an analysis that is not out ofplace in the context of the current debate.John N. Davis II*, Jane C. Chisholm†*Department of Neurology, University of Virginia,Charlottesville, Virginia 22908, USA†Department of Pharmacology and Physiology,University of Rochester,Rochester, New York 14642, USA

1. St George-Hyslop, P. & Westaway, D. Nature 400, 116–117 (1999).

2. Hardy, J. H. Trends Neurosci. 20, 154–159 (1997).

3. Davis, J. N. & Chisholm, J. C. Trends Neurosci. 20, 558–559 (1997).

4. Bick, K. et al. (eds) The Early Story of Alzheimer’s Disease

(Liviana, New York, 1987).

5. Alzheimer, A. Zschr ges Neurol. Psychiat. 4, 356–385 (1911).

6. Förstl, H. & Levy, R. History of Psychiatry 2, 71–101 (1991).

Alois Alzheimer and theamyloid debate

Sir — Peter St George-Hyslop and DavidWestaway discuss the possibility of usingAb immunization to treat Alzheimer’sdisease1. They mention the continuingcontroversy2,3 surrounding the role ofextracellular Ab accumulation and amyloidplaques in the causation of the dementiaassociated with the disease, referring to thisas “an old debate”. What is not widelyrecognized is how old the question at thecentre of this debate actually is.

Alois Alzheimer and hiscontemporaries4 considered this veryquestion. In a 1911 paper entitled “Oncertain peculiar diseases of old age”5,Alzheimer writes: “There are cases ofindubitable Dementia senilis, in which theplaques are not very numerous. Moreover,as Fischer stresses, they dislocate thenervous structures more than they destroythem. So the loss of cortical tissue due to theplaques cannot be very considerable.Furthermore, in places where plaques arenot found in the cerebral cortex, we see the

Global emissions couldsoon start rising again

Sir — Some loose ends appear in yourreport of the Worldwatch Institute’sestimates of global carbon emissions fromfossil fuel use in 1998 (Nature 400, 494;1999). The industry report cited estimatedthat global emissions had fallen by 0.47%from 1997 levels, based on a US reductionof 0.2%. The US Environmental ProtectionAgency later estimated that 1998 USemissions had increased by 0.4%. Thisindicates that global emissions declined by0.3%. The Worldwatch Institute claimed a0.5% global reduction, despiteacknowledging the +0.4% US figure.

In fact, the global reduction seems tohave been more than 1%. This is owing to areduction of more than 3% in theAsia–Pacific region and of more than 2% inthe economies in transition in EasternEurope and the former Soviet Union.Developing countries overall saw a declineexceeding 3% (though still up 33% on 1990levels) because the decline in Asia morethan offset small increases elsewhere. Bycontrast, emissions rose 1% in theEuropean Union.

Reductions around the world weremainly the result of presumably temporaryeconomic difficulties. In many cases theyoccurred in countries that are neitherindustrialized nor transitional economieslisted in annex I of the climate conventionand annex B of the Kyoto Protocol.

The Worldwatch Institute’s belief that