Lewis and Clark

[Seosamh]

I've read somewhere that Thomas Jefferson hoped (or expected?) that
the Lewis and Clark expedition would find evidence of living
populations of mammoths. What led him to believe that there could be
such animals alive? Even without carbon dating, isn't a fossil visibly
"old enough" that it can't be mistaken for "fresh?" I tend not to get
distracted by "Halls of Mammals" when there are dinosaur fossils to
see, so am I missing something in the nature of material from
thousands, vs. millions, of years ago?

Thanks,

Joe

[Brad McFeeters]

http://www.ansp.org/museum/jefferson/otherPages/extinction.php

[Seosamh]

On Oct 1, 8:55 pm, Brad McFeeters <rug...@gmail.com> wrote:
> http://www.ansp.org/museum/jefferson/otherPages/extinction.php

So the fossils lying on the ground looked like they were "fresh?"
Wouldn't animals have continued gnawing on them for marrow if
something hadn't chemically altered them?

"There was no compelling reason to believe the remains belonged on
extinct animals, or that they were of great age." Given that they
didn't understand (or perhaps didn't lend credence to) extinction at
the time, they still would be looking at something that wasn't bone
any more. Did Jefferson ever see any of the fossils himself, I wonder.

Interesting quote from Jefferson on that page:
"For if one link in nature's chain might be lost, another and another
might be lost, till this whole system of things should be evanish by
piece-meal."

Maybe he could have made EPA a cabinet-level department? ;)

Thanks,

Joe

[Frank Mishenko]

Have a look at:
http://www.earlyamerica.com/review/2000_fall/jefferson_paleon.html

[David Bressan]

In 1796 the third president of the United States, also president of
the American Philosophical Society and naturalist Thomas Jefferson
(1743-1826) studied some fossil bones and a giant claw discovered
during mining activities in a cave.
March 10, 1797 he presented the results to the Philosophical Society
under the title "A Memoir on the Discovery of Certain Bones of a
Quadruped of the Clawed Kind in the Western Parts of Virginia" and
concluded that these remains belong to a giant felid " three times as
large as the lion" which he named "Megalonyx" (great claw). Jefferson,
in accordance to the naturalistic knowledge of the time, believed that
in nature no species could became extinct, so he continued in his
report:

"In the present interior of our continent there is surely space and
range enough for elephants and lions, if in that climate they could
subsist; and for the mammoth and megalonyxes who may subsist there.
Our entire ignorance of the immense country to the West and North-
West, and of its contents, does not authorise us so say what is does
not contain."

Jefferson based this conclusion in part on anecdotes of woodsmen being
terrorized by a large cat-like animal in the wilderness and the
presumed representations of lions in Indian rock paintings (possibly
the American lion Panthera atrox ?).

However the most important argument for Jefferson was a theological
one: if a species can become extinct in a perfect divine creation such
a creation can't possibly be so perfect all along, the continuous loss
of species would inevitable lead to the end of this imperfect
creation.

"The movements of nature are in a never ending circle. The animal
species which has once been put into a train of motion, is still
probably moving in that train. For if one link in nature's chain might

be lost, another and another might be lost, till this whole system of

things should be evanish by piece-meal; a conclusion not warranted by
the local disappearance of one or two species of animals, and opposed
by the thousands and thousands of instances of the renovating power
constantly exercised by nature for the reproduction of all her
subjects, animal, vegetable, and mineral."

Jefferson also had some political motives to support the existence of
large and ferocious animals in the U.S.
In his works the eminent France naturalist Georges-Louis Leclerc,
Comte de Buffon (1707-1788) proposed a theory to explain the worldwide
distribution of animal species: from environmental optimal centres
species would spread all over the globe, however degenerating in areas
with less favourable climate or environment - and according to Buffon
the fauna of America was an perfect example of such a degenerated
European and African fauna.
This worldview not only offended Jefferson's personal feelings, but
also seriously damaged the reputation of the young United States of
America. The U.S. needed the political and financial support of France
during the Revolutionary Wars (1775-1783), Buffon was however
popularizing the perception that "America is an excessively cold and
humid continent where big animals cannot survive, domestic animals
become scrawny, and men become stupid and lose their sexual
vigor" (ROWLAND 2009)

In spring 1785 Jefferson published anonymous his "Notes on the State
of Virginia", where he discussed naturalistic and also political facts
of this state. In various lists he compared the mammals of the new
continent to the mammals of the old continent, concluding that the
body mass and diversity of American animals was far superior then
envisaged by Buffon. He also reaffirmed his view on the impossibility
of extinction:

"The bones of the Mammoth which have been found in America, are as
large as those found in the old world. It may be asked, why I insert
the Mammoth, as if it still existed? I ask in return, why I should
omit it, as if it did not exist?
Such is the economy of nature, that no instance can be produced of her
having permitted any one race of her animals to become extinct; of her
having formed any link in her great work so weak as to be broken. To
add to this, the traditionary testimony of the Indians, that this
animal still exists in the northern and western parts of America,
would be adding the light of a taper to that of the meridian sun.
Those parts still remain in their aboriginal state, unexplored and
undisturbed by us, or by others for us. He may as well exist there
now, as he did formerly where we find his bones."

In 1803 Jefferson organized the famous Lewis and Clark expedition;
apart political important tasks, like the geographical exploration of
Louisiana and the search for a navigable passage to the Pacific, this
expedition should also dig for fossils and search for the supposed
unknown large tetrapods of North America.

Jefferson in his lifetime never really embraced the theory of
extinction, probably as a results of personal religious beliefs and
political agenda - only in the mid 19th century extinction will become
a scientific fact.

Bibliography:

ROWLAND, S.M. (2009): Thomas Jefferson, extinction, and the evolving
view of Earth history in the late eighteenth and early nineteenth
centuries. In ROSENBERG, G.D., ed., The Revolution in Geology from the
Renaissance to the Enlightenment: Geological Society of America Memoir
203: 225-246