The Sacred Ibis debate: The first test of evolution

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558


The Sacred Ibis debate: The first test of evolution

* Caitlin Curtis,
* Craig D. Millar,
* David M. Lambert

*


*



*




PLOS

* Published: September 27, 2018
* https://doi.org/10.1371/journal.pbio.2005558

* Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558>
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* Related Content
<https://journals.plos.org/plosbiology/article/related?id=10.1371/journal.pbio.2005558>

* Abstract <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#abstract0>
* Introduction <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#sec001>
* Mistaken identity: Ibis mummies were misidentified as "storks"
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#sec002>
* Opposing views within the French National Museum of Natural History: Cuvier and Lamarck
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#sec003>
* Cuvier performed the first test of evolution
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#sec004>
* Sacred Ibis mummies become the focus of evolutionary debate
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#sec005>
* The Great Debate
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#sec006>
* Conclusion <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#sec007>
* Acknowledgments <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#ack>
* References
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#references>

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Abstract

In 1798, Napoleon Bonaparte's army invaded Egypt, returning with many treasures including large
numbers of Sacred Ibis mummies. The ancient Egyptians revered the ibis and mummified literally
millions of them. The French naturalist Georges Cuvier used these mummies to challenge an emerging
idea of the time, namely Jean-Baptiste Lamarck's theory of evolution. Cuvier detected no measurable
differences between mummified Sacred Ibis and contemporary specimens of the same species.
Consequently, he argued that this was evidence for the "fixity of species." The "Sacred Ibis debate"
predates the so-called "Great Debate" between Cuvier and Geoffroy Saint-Hilaire and the publication
of Darwin's On the Origin of Species five decades later. Cuvier's views and his study had a profound
influence on the scientific and public perception of evolution, setting back the acceptance of
evolutionary theory in Europe for decades.


Figures

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Citation: Curtis C, Millar CD, Lambert DM (2018) The Sacred Ibis debate: The first test of
evolution. PLoS Biol 16(9): e2005558. https://doi.org/10.1371/journal.pbio.2005558

Published: September 27, 2018

Copyright: © 2018 Curtis et al. This is an open access article distributed under the terms of the
Creative Commons Attribution License <http://creativecommons.org/licenses/by/4.0/>, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and
source are credited.

Funding: Human Frontier Science Program http://www.hfsp.org/ (grant number RGP0036/2011). The
funding was received by DML. The funder had no role in study design, data collection and analysis,
decision to publish, or preparation of the manuscript. Royal Society of New Zealand
https://royalsociety.org.nz/. The funding was received by DML. The funder had no role in study
design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Provenance: Not commissioned; externally peer reviewed


Introduction

When Napoleon's army invaded Egypt in 1798, his soldiers collected many treasures. The most famous
of these was the Rosetta Stone discovered by a French soldier in 1799. This tablet comprised three
versions of a decree that eventually enabled the deciphering of Egyptian hieroglyphics [1
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref001>].
Ironically, the stone was captured by the British at the French surrender of Alexandria and never
made it to French soil. It has been in the British Museum since 1802. Of almost equal fascination at
the time was the large number of animal mummies that were brought back to France as "spoils of war."
Many species, including cats, jackals, dogs, crocodiles, snakes, ibis, and other birds, as well as
human mummies, were described in exquisite detail in the Description de l'Égypte (1809–1829). Like
the Rosetta Stone, many of these mummies were deposited in museums.

These mummies captivated the imagination of the public. Numerous "unwrappings" of human and animal
mummies took place, including several ibis [2
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref002>,
3
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref003>].
The Egyptians mummified literally millions of these birds and stored them in vast underground
catacombs [2
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref002>].
In addition to the extensive military forces, the French invasion included a remarkable delegation
of more than 150 civilian intellectuals, called savants, including Geoffroy Saint-Hilaire, who would
later become an important figure in the development of evolutionary thought. The savants established
the Egyptian Institute (Institut d'Égypte) and went on to painstakingly collect and document the
physical, natural, and cultural history of the region. The Sacred Ibis (Threskiornis aethiopicus)
mummies ignited a fierce debate about the reality of evolution between two of the giants of 19th
century natural history, Georges Cuvier and Jean-Baptiste Lamarck (Fig 1
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio-2005558-g001>).
This debate preceded the "Great Debate" and occurred decades before the publication of the pivotal
works of Charles Darwin and Alfred Russel Wallace on natural selection and evolution.

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Fig 1. The two central figures in the first test of evolution.

(A) Georges Cuvier (1769–1832) and (B) Jean-Baptiste Lamarck (1744–1829).

https://doi.org/10.1371/journal.pbio.2005558.g001 <https://doi.org/10.1371/journal.pbio.2005558.g001>


Mistaken identity: Ibis mummies were misidentified as "storks"

In Egypt, animal mummies vastly outnumbered those of humans [4
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref004>].
The catacombs at Tuna el-Gebel in Egypt, for example, are estimated to contain 4 million Sacred Ibis
mummies [5
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref005>],
many of which are well preserved (Fig 2
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio-2005558-g002>).
Ancient Egyptians revered the Sacred Ibis as a manifestation of Thoth, the god of wisdom and
writing. Images of ibis were used in hieroglyphic writings and as amulets and statues representing
Thoth. From the Late Period onward (ca. 7th century BC), these birds were mummified as offerings to
Thoth. Generally, once killed, they were desiccated with salts and covered with oils and resins. The
wrapped birds were then typically sealed in large pottery vessels—sometimes two or more to a pot
(Fig 2
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio-2005558-g002>).
Others were placed in wooden coffins or covered with a layer of cartonnage (similar to
"papier-mâché") that was plastered and painted [4
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref004>].

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Fig 2. Mummified Sacred Ibis.

(A) Empty and full pottery vessels from catacombs from Saqqara, Egypt (photo credit Sally Wasef),
(B) mummified Sacred Ibis wrapped in cloth (photo credit Metropolitan Museum of Art, New York), (C)
a well-preserved example of an unwrapped Sacred Ibis mummy (the head and wings of the bird are
clearly visible), and (D) a mummified Sacred Ibis dipped in resin.

https://doi.org/10.1371/journal.pbio.2005558.g002 <https://doi.org/10.1371/journal.pbio.2005558.g002>

By the late 18th century, most scholars mistakenly believed that the Sacred Ibis mummies were
actually yellow-billed storks (then Tantalus ibis, now Mycteria ibis) [6
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref006>]
(Fig 3
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio-2005558-g003>).
This error is perhaps understandable given that Sacred Ibis populations were not present in Europe
at the time. Therefore, 18th century specimens of Sacred Ibis in Europe were limited to a few
unidentified birds in museums.

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Fig 3. Stork and ibis.

(A) Yellow-billed stork (photo credit Becky Matsubara) and (B) Sacred Ibis (photo credit Christiaan
Kooyman).

https://doi.org/10.1371/journal.pbio.2005558.g003 <https://doi.org/10.1371/journal.pbio.2005558.g003>


Opposing views within the French National Museum of Natural History: Cuvier and Lamarck

While Napoleon's Egyptian conquest included many prominent scientists, the French naturalist Georges
Cuvier chose to remain in Paris at the French National Museum of Natural History, where he would
later very publicly argue his opposition to evolution. At the time of the Egyptian conquest,
however, Cuvier was developing his principle of the "correlation of parts." Primarily, Cuvier
believed that an organism's parts were perfectly adapted and linked in such a way that any
modification to one of the parts would prevent the survival of the organism as a whole. The
correlation of parts was so pervasive and powerful that Cuvier believed it could be used to predict
the function of any particular part as well as its relationship to the organism as a whole. Using
this principle, Cuvier proclaimed to be able to predict the entire form of any organism from mere
fragments of bones or a few organs—including reconstructing entire skeletons of extinct creatures
from fossilized bones.

Furthermore, Cuvier's belief in the correlation of parts led him to argue for the "fixity of
species" or the idea that each species is based on an ideal form that cannot change over time [7
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref007>].
Though Cuvier was unyielding in his belief that species were unchanging and did not evolve, he
rightly argued that extinctions had been widespread throughout the Earth's geological history.
Cuvier recognized the existence of fossilized species for which no modern relative existed, a
revolutionary idea at the time. However, Cuvier rejected the idea that such fossilized remains could
have been the ancestors of living forms [8
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref008>].

Cuvier's idea of the "fixity of species" was in conflict with the views of Lamarck, his contemporary
at the museum. However, Lamarck's prestige and political influence was modest in comparison to
Cuvier's ever-increasing prominence, intellect, and showmanship. These attributes contributed to his
notoriety in the scientific and popular culture of the time. In contrast to the "fixity of species,"
Lamarck argued for a continuous slow transmutation of animal species over time (now known as
"phyletic gradualism") [9
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref009>].
In Lamarck's theory of transmutation (or species mutability), species would proceed up the "Great
Chain of Being" [10
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref010>]
from simple to complex, with humans at the pinnacle. Lamarck's Philosophie Zoologique [9
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref009>]—published
half a century before Darwin's On the Origin of Species—included the following ideas: species change
through evolutionary time; evolutionary change is slow and imperceptible; evolution occurs through
adaptation to the environment; it generally progresses from the simple to the complex, although in a
few cases, it proceeds in reverse; and species are related to one another by common descent.
Furthermore, Lamarck's theory incorporated the fact that the world is old and proposed that life was
a result of abiogenesis, i.e., the origin of life derives from inanimate matter [11
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref011>].


Cuvier performed the first test of evolution

Cuvier had the opportunity to study two Sacred Ibis mummies that were collected by Saint-Hilaire,
who also worked at the National Museum of Natural History in Paris. Their coloration matched that of
the yellow-billed stork: white plumage and wing feathers marked with black, but the bones were too
small to be a stork and the shape of the beak was wrong—it was curved, not straight like that of a
stork (Fig 3
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio-2005558-g003>).
One conceivable explanation for these differences was evolution: namely, that "storks" had
morphologically changed since the time of the Egyptians [6
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref006>].

As more mummies were brought back from Egypt, Cuvier's assistant Rousseau was able to assemble a
composite skeleton. This skeleton remains on display at the museum. Cuvier used this skeleton (and
other loose bones from mummies) to make many careful morphometric measurements of the mummified
birds. According to Cuvier, there had been no changes in the morphology of the Egyptian mummified
"stork" over time. Cuvier compared the mummified bones to skeletons of six avian specimens of
another species with similar general characteristics. These specimens had an equivalent coloration,
body size, and, most importantly, a curved beak. He included two known stork specimens (M. ibis) in
the analysis. Cuvier carefully recorded body part measurements from all of these birds.

Based on these measurements, Cuvier correctly established that the mummies were not storks. He
determined that the mummified birds matched the unclassified birds from the museum. Cuvier went on
to name these birds Numenius ibis, and they have subsequently been reclassified as T. aethiopicus
(Sacred Ibis). Cuvier also recovered a few uniquely shaped black feathers from a mummy that provided
further evidence for his identification of the mummified birds as ibis. To Cuvier's knowledge, these
distinctive black feathers were a characteristic of the genus Numenius. Cuvier preserved these
feathers for future examination as "a remarkable monument of antiquity and a peremptory proof of the
identity of species" [12
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref012>].

The measurements of the mummified bones were not a perfect match with those taken from the museum
specimens of Sacred Ibis. However, the measurements between the ancient material and the
then-contemporary Sacred Ibis were similar, and Cuvier concluded that no detectable anatomical
changes had occurred over time. This made him the first to test the idea of evolution.


Sacred Ibis mummies become the focus of evolutionary debate

Lamarck and Cuvier publicly presented the animal mummies to the French Academy in 1802, along with
Comte de Lacépède [13
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref013>].
Referring to the mummies, the latter author remarked, "these animals are perfectly similar to those
of today" [14
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref014>].
Cuvier also described the lack of change in the ibis mummies as follows: "We certainly do not
observe more differences between these creatures and those which we see today than between human
mummies and today's human skeletons." [12
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref012>].
Whilst Cuvier and Lamarck agreed in their presentation to the Academy that no discernible changes
had taken place since the time of the Egyptians, their opposing views regarding the "fixity of
species" led them to clash on the significance of the findings. Lamarck insisted that extensive
periods of time with changing environmental conditions would be required to see the slow, gradual
changes (i.e., transmutations) in organisms over time [9
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref009>].
Lamarck's argument was that a passage of 3,000 years would have been insufficient to observe
evolutionary processes because the environmental conditions in Egypt had not changed during this
time. According to Lamarck, "It would indeed be very odd if it were otherwise; for the position and
climate of Egypt are still very nearly what they were in those times. Now the birds which live
there, being still in the same conditions as they were formerly, could not possibly have been forced
into a change of habits" [9
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref009>].
Cuvier acknowledged that only 2,000 to 3,000 years had elapsed at most (this estimate was recently
shown to be accurate [15
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref015>]),
but he denied that evolution would result from longer periods of time. He argued that longer
timescales simply contain the sum of changes within shorter periods. In other words, he reasoned
that since no changes had been observed over approximately 3,000 years, it was unreasonable to argue
that any longer timescale would produce them. Cuvier went on to publicly argue that his study on the
Sacred Ibis was evidence for the "fixity of species" in opposition to Lamarck. Throughout his
career, he produced several increasingly refined iterations of his case study of the mummified ibis
that were published from the late 18th century to at least 1827. Cuvier even carried his argument
through to Lamarck's death, incorporating it into his spiteful eulogy for Lamarck [16
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref016>].


The Great Debate

The Sacred Ibis debate set the scene for a much more intense controversy. A year after Lamarck's
death in 1829, a heated debate ensued in the French Academy of Sciences. This is commonly referred
to as "The Great Debate" (Fig 4
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio-2005558-g004>)
(as distinct from the later debate between Huxley and Wilberforce). The debate was a broad
philosophical exchange about the importance of functional properties of organisms and the "fixity of
species", what we now know as evolution. As in the Sacred Ibis debate, Cuvier was one of the central
participants, but on this occasion, Cuvier's protagonist was Saint-Hilaire. Saint-Hilaire generally
supported Lamarck's evolutionary ideas but emphasized organisms as products of the laws and
principles of biology. Cuvier argued that the functional properties of organisms explained their
existence through the will of a divine creator.

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Fig 4. A timeline showing some of the major events in the history of the first test of evolution.

https://doi.org/10.1371/journal.pbio.2005558.g004 <https://doi.org/10.1371/journal.pbio.2005558.g004>


Conclusion

The case of the Sacred Ibis highlights the disproportionate influence that a charismatic and
dominant personality like Cuvier can have. The magnitude of Cuvier's influence has been the subject
of discussion [17
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref017>],
but, as Burkhardt [18
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref018>,
19
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref019>]
argued, "…Cuvier's magisterial and disapproving presence has long been recognised as a factor in the
poor reception of Lamarck's evolutionary theory by his contemporaries." Cuvier's unwillingness to
consider the potential for very small differences to accumulate over much longer timeframes enabled
him to interpret his study in a way that supported his own beliefs and set back the acceptance of
evolution for the next five decades [6
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio.2005558.ref006>].
The debate about the Sacred Ibis is an important but often unrecognized episode in the history of
science. Of great importance is the reminder, even today, of the power of a strong personality and
that the belief in "what they know to be true" can dramatically influence the direction of science
and public opinion.


Acknowledgments

We thank Ashley Hay for valuable feedback and helpful comments on the manuscript. We are also
grateful to Sally Wasef for the image used in Fig 2A
<https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#pbio-2005558-g002>.


References

1. 1. Ray J. The Rosetta Stone and the rebirth of Ancient Egypt. London: Profile Books; 1996.
2. 2. Taylor JH. The collection of Egyptian mummies in the British Museum: Overview and potential
for study. In: Fletcher A, Antoine D, Hill JD, editors. Regarding the Dead: Human Remains in the
British Museum. London: British Museum Press; 2014. pp. 103–114.
3. 3. Pearson J. Some account of two mummies of the Egyptian Ibis, one of which was in remarkably
perfect state. J Philos Trans R Soc Lond. 1805; 95: 264–271.
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* Google Scholar
<http://scholar.google.com/scholar?q=Some+account+of+two+mummies+of+the+Egyptian+Ibis%2C+one+of+which+was+in+remarkably+perfect+state+Pearson+1805>
4. 4. Ikram S. Divine creatures: Animal mummies in ancient Egypt. Cairo: American University in
Cairo Press; 2005.
5. 5. El Mahdy C. Mummies, myth and magic in ancient Egypt. London: Thames and Hudson;1989.
6. 6. Rudwick MJS. Bursting the limits of time. Chicago: The University of Chicago Press; 2005.
7. 7. Coleman W. Georges Cuvier, Zoologist: A Study in the History of Evolution Theory. Cambridge,
Massachusetts: Harvard University Press; 1964.
8. 8. Honeywill R. Lamarck's evolution. Two centuries of genius and jealousy. Sydney: Murdock
Books; 2008.
9. 9. Lamarck J-B. Zoological Philosophy: An exposition with regard to the natural history of
animals. United States of America: University of Chicage Press; 1984.
10. 10. Lovejoy AO. The great chain of being: A study of the history of an idea. Boston: Harvard
University Press; 1936.
11. 11. Graur D, Gouy M, Wool D. In retrospect: Lamarck's treatise at 200. Nature. 2009; 460:
688–689. https://doi.org/10.1038/460688a
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* Google Scholar
<http://scholar.google.com/scholar?q=In+retrospect%3A+Lamarck%E2%80%99s+treatise+at+200+Graur+2009>
12. 12. Cuvier G. Discourse on the revolutionary upheavals on the surface of the globe and on the
changes which they have produced in the animal kingdom [Translated by Ian Johnston]. Arlington:
Richer Resources; 2009.
13. 13. Lacépède B-G-E, Cuvier G, Lamarck J-B. Rapport des professeurs du Muséum sur les collections
d'histoire naturelle rapportées d'Égypte. Annales du Museum d'Histoire Naturelle. 1802; 1: 234–241.
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* Google Scholar
<http://scholar.google.com/scholar?q=Rapport+des+professeurs+du+Mus%C3%A9um+sur+les+collections+d%26apos%3Bhistoire+naturelle+rapport%C3%A9es+d%26apos%3B%C3%89gypte+Lac%C3%A9p%C3%A8de+1802>
14. 14. Burkhardt RW. Lamarck, evolution, and the inheritance of acquired characters. Genetics.
2013; 194: 793–805. pmid:23908372
* View Article <https://doi.org/10.1534/genetics.113.151852>
* PubMed/NCBI <http://www.ncbi.nlm.nih.gov/pubmed/23908372>
* Google Scholar
<http://scholar.google.com/scholar?q=Lamarck%2C+evolution%2C+and+the+inheritance+of+acquired+characters+Burkhardt+2013>
15. 15. Wasef S, Wood R, Ikram S, Curtis C, Holland B, Willerslev E, Millar C, Lambert DM.
Radiocarbon dating of Sacred Ibis mummies from ancient Egypt. J Archaeol. Sci. 2015; 4: 355–361.
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* Google Scholar
<http://scholar.google.com/scholar?q=Radiocarbon+dating+of+Sacred+Ibis+mummies+from+ancient+Egypt+Wasef+2015>
16. 16. Cuvier G. Elegy of Lamarck. New Philos J Edinb. 1836; XX: 1–22.
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* Google Scholar <http://scholar.google.com/scholar?q=Elegy+of+Lamarck+Cuvier+1836>
17. 17. Corsi P. The revolutions of evolution: Geoffroy and Lamarck, 1825-1840. Bulletin du Musée
d'Anthropologie Préhistorique de Monaco. 2012; 51: 97–122.
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* Google Scholar
<http://scholar.google.com/scholar?q=The+revolutions+of+evolution%3A+Geoffroy+and+Lamarck%2C+1825-1840+Corsi+2012>
18. 18. Burkhardt W. Lamarck, evolution, and the politics of science. J Hist Biol. 1970; 3: 275–298.
pmid:11609655
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* PubMed/NCBI <http://www.ncbi.nlm.nih.gov/pubmed/11609655>
* Google Scholar
<http://scholar.google.com/scholar?q=Lamarck%2C+evolution%2C+and+the+politics+of+science+Burkhardt+1970>
19. 19. Burkhardt RW. The Leopard in the garden: life in close quarters at the Muséum d'Histoire
Naturelle. Isis. 2007; 98: 675–694. pmid:18314641
* View Article <https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005558#>
* PubMed/NCBI <http://www.ncbi.nlm.nih.gov/pubmed/18314641>
* Google Scholar
<http://scholar.google.com/scholar?q=The+Leopard+in+the+garden%3A+life+in+close+quarters+at+the+Mus%C3%A9um+d%E2%80%99Histoire+Naturelle+Burkhardt+2007>

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