THE TROPICS IN DANGER 
The JAGUAR is one of the many inhabitants of tropical rain forests — in fact, more than half 
of the world's plants and animals live in these forests. 
If present trends continue 500,000 or more species will be extinct within the next 20 years. 
Most of these losses will occur in tropical rain forests. 
Concerned people everywhere must band together to protect these vital resources. 
RARE is a non-profit, volunteer based organization devoted to the protection of endangered 
plants and animals. RARE is doing all it can but WE NEED YOUR HELP TO PROTECT THE 
JAGUAR. Your contribution will help save this beautiful cat. 
The "Jaguar" painting by Bonnie L. Marris is available in three 18x24 full color editions. 
(1) Jaguar conservation poster with a contribution of $15.00. 
(2) Signed and numbered print from the limited edition of 500, on 100% cotton stock, with 
a remittance of $125.00. 
(3) Special remarqued edition of 250 prints with a donation of $175.00. 
Please specify your choice and make checks payable to RARE, Inc. 
Rare Animal Relief Effort, inc. 
c /o National Audubon Society 
950 Third Avenue, New York, N Y 10022 
Your generous contributions are deductible for Federal income tax purposes 
to the extent allowed by law. 
ket” that holds reproductive cells and 
transmits itself in toto from generation 
to generation. (The fertilized egg, of 
course, is formed by the union of two 
reproductive cells. As it starts to divide, 
however, the nonreproductive cells 
form, eventually develop into the or- 
ganism’s body, and become rigidly seg- 
regated from the continuous lineage of 
germ cells. Telegony makes no sense 
because, even if they existed, male gem- 
mules in a female’s body could not get 
to the germ cells — unless, of course, 
they managed to reach the ovaries 
themselves and modify the immature 
ova.) 
Telegony kicked about in scientific 
literature for seventy years, from Mor- 
ton’s note to the Royal Society in 1820 
until Weismann’s challenge. When 
Weismann proposed the continuity of 
germ plasm, telegony became a threat- 
ening anomaly demanding affirmation 
or rejection. Many tests were made, and 
telegony failed them miserably. In par- 
ticular, J.C. Ewart, Regius Professor of 
Natural History at Edinburgh, tried to 
repeat Morton’s own experiment. Since 
quaggas had joined Eohippus in the 
realm of departed horses, Ewart mated 
twenty mares of different races and 
breeds with a male Burchell’s zebra. 
The first hybrid, born in 1896, had 
stripes as expected. Ewart then mated 
the mare with a second sire, an Arab 
stallion. Their offspring also had 
stripes, albeit faint, and telegony 
seemed vindicated. But Ewart knew 
that he needed controls and therefore 
bred the same Arab stallion to other 
mares that “had never so much as seen 
a zebra.” The offspring of these matings 
were as richly striped as the foal from 
the mare that had previously mated 
with a zebra. Darwin had been right the 
first time. Stripes do not arise from a 
mysterious previous zebra influence; 
they represent a potential pathway of 
development for all horses. 
I have not recounted this tale of te- 
legony for its own sake, since antiquar- 
ian musings only excite professionals 
and trivia buffs. Rather, as Burkhardt 
emphasizes, the story embodies a larg- 
er, troubling, and important issue about 
the nature of fact in science. Telegony, 
so far as we can tell, was wrong; yet it 
remained in the literature as a pristine 
fact, largely unchallenged, for seventy 
years. In a reversal of the stereotyped 
scenario, where a single sturdy fact 
arises to destroy an entire edifice of the- 
ory, the “fact” of telegony came first, 
became entrenched, and was only seri- 
ously challenged when a theory — Weis- 
18 
