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American Paleontology and Neo- Lamarckism ELEVENTH REPORT AMERICAN PALEONTOLOGY AND NEO- OF LAMARCKISM. THE MICHIGAN ACADEMY OF SCIENCE E. C. CASE. CONTAINING AN ACCOUNT OF THE ANNUAL The terms Neo-Lamarckism and Neo-Lamarckian were MEETING first used by Prof. A. A. Packard in 1885 (Introduction to HELD AT the Standard Natural History.) The foundations of the school were laid before Darwins time in the writings of ANN ARBOR, MARCH 31, APRIL 1 AND 2, 1909. Lamarck. He taught—First, that in animals which have not passed DARWIN CENTENARY PUBLICATION the limit of their development the continued use of an organ increases its size and power and that conversely the lack of use leads to deterioration. Second, that the PREPARED UNDER THE DIRECTION OF THE condition or character thus acquired is transmitted by COUNCIL heredity to its offspring. Here we have the origin of a variation. Darwin's great work added the factor lacking BY in Lamarckism and brought a vague hypothesis to the GEO. D. SHAFER, condition of a working principle by elaborating his ACTING SECRETARY conception of a Natural Selection. BY AUTHORITY It is generally conceded today that Natural Selection can 1909 not originate a variation, the basis of all evolution; but is the dominant factor in the preservation of variations once originated and their development into species. TABLE OF CONTENTS. Lester Ward in an address before the Biological Society of Washington, in 1891 makes the union of these two principles the basis of the Neo-Lamarckian School.. He Letter of Transmittal. ......................................................... 1 said, "Neo-Lamarckism, as I understand it, while Papers published in this Report: recognizing natural selection as the more prominent of the two agencies, also recognizes that the increments of 3. American Paleontology and Neo-Lamarckism, change impressed on individuals during their lifetime or Prof. E. C. Case............................................................. 1 brought about by individual efforts or habits are also 15. The Brown Iron Ores of Spring Valley, Wisconsin, perpetuated in some measure through heredity and R. C. Allen. .................................................................... 5 form, an important factor in the general process of Officers for 1909-1910. ..................................................... 9 organic development." As will be shown, the present content of the Neo- Lamarckian idea is not compassed by this definition LETTER OF TRANSMITTAL. though it is a clear outgrowth therefrom. Neo-Lamarckism has received a considerable, if not its TO HON. FRED M. WARNER, Governor of the State of chief, body of support from the American Michigan: paleontologists. This has rather been due the conditions which have presented to them a large body of evidence SIR—I have the honor to submit herewith the Eleventh in a peculiar way than to the presence of any dominant Annual Report of the Michigan Academy of Science for leader of the movement. The paleontologists of publication, in accordance with Section 14 of Act No. 44 America, and especially those working among of the Public Acts of the Legislature of 1899. vertebrates have been especially fortunate in that they Respectfully, have found almost at their doors large numbers of beautifully preserved fossils representing long GEO. D. SHAFER, Acting Secretary of the Michigan Academy of Science. phylogenetic lines and preserved in undisturbed strata, East Lansing, Mich., June 16, 1909. rendering the sequence of the deposition certain. European workers have not failed in their appreciation of the claims of this school but have rather lacked the same opportunities. I take it to be a most significant fact that workers along such divergent lines as fossil vertebrates, fossil invertebrates and fossil leaves, but having in common the opportunity to view long phylogenetic lines should come to a common conclusion. The paleontologist does Selections from the 11th Annual Report of the Michigan Academy of Science – Page 1 of 9 not have the chance to view large numbers of individuals introducing the new phase of Neo-Lamarckism. S need and so fails to have impressed upon him the frequency not be discussed, for according to the Neo-Lamarckian of variation; also it is the exception that he can trace the school it can not be admitted as a factor having to do individual variations which are caused by geographical with the origin of variations, though nearly all powerful in changes, but to compensate for this his material affords their preservation. him surpassing opportunity for a just appreciation of the The Buffonian factor of evolution may be expressed in influence of time and heredity. The nature of the the formula by E x o x h X s. Emphasizing the evidence has in a manner forced the conclusions of the predominant effect of the environment. Dall in his paper paleontologist and has at the same time armed him for a on the Dynamic Influences of Environment said: "The defence of his conclusions based largely upon deduction environment stands in relation to the individual as the and permitted him to leave speculation in the hammer and the anvil to the blacksmiths hot iron. The background. organism suffers during its entire existence a continuous It is always a thankless task to call the roll and appraise series of mechanical impacts, none the less real the results of any body of workers, but certain men have because invisible." As Merriam said these are bold stood out so prominently in the development of the Neo- words but weighty and well worth considering. Lamarckian school that we may name them without fear The Lamarckian factor may be represented by the of contradiction. Cope, Ryder, Scott and 0shorn among formula, O x h x e x s, i. e. The development of a the vertebrate paleontologists, Dall and Hyatt among character during the life of the individual and the workers on invertebrates and Lester Ward of the establishment of this character by heredity. paleobotanists; the work of these men may be taken as epitomizing the growth of Neo-Lamarckism in America. But Lamarckism has failed to answer several questions Of these Cope, Ryder, Dall and Hyatt may be regarded which have been proposed, as the founders of the school. In 1886, Hyatt read his 1. How can a character acquired during senility be paper "On the parallelism between the different stages transmitted to offspring which are born before the of life in the individual and those of the entire group of character is acquired, and still the offspring develop the the Mollusc an order Tetrabranchiata" in 1880 he senile characters of the parent. defined his ideas more clearly in two papers "Upon the effects of gravity upon the shells of animals" and "The 2. Neo-Darwinians have formulated the following test for genesis of Tertiary species of Planorbis at Steinheim." the transmission of acquired characters. If a form is In 1890 Dall published his paper on the "Dynamic placed in a new environment it will frequently develop Influences in Evolution." In 1871 appeared Ryders new characters, but if the offspring even of the third or paper "On the laws of digital reduction" and in 1879 fourth generation, which has the new characters, be another "On the mechanical genesis of tooth forms,” transferred back to the original environment the other papers from this author appeared at intervals until characters assumed during the changed condition will 1890 upon similar themes. Copes Origin of the fittest disappear. The acquired characters were not fixed. appeared in 1887 and the Primary Factors of Evolution Lamarckism has not yet pointed to an undoubted case of in 1896. These books were in large part republications the fixity of acquired characters. of essays printed at earlier dates. 3. Experimenters can not say whether the characters These papers represent a distinct stage in the which appear under changed conditions are new or development of the Neo-Lamarckian school for they whether they are reversions to a previous condition insist on the origin of variations from the effect of strains when the animals lived in an environment similar to the set up by the environment or by the effort of the one in which it is placed by the experimenter. individual and on the preservation of these variations by natural selection. This is, perhaps, Neo-Lamarckism in 4. Lamarckism can not explain the growth and its purest phase. development or rudimentary structures. It cannot account for the development of characters which are The continued studies of long phylogenetic lines such as useless. the labors of the American paleontologists were perfecting led to the recognition of the fact that Neo- Now having rejected other explanations what has the Lamarckism as defined above was not competent to Neo-Lamarckian to offer instead. I fear that he comes answer all questions which arose and so there has been with little but a wealth of observation and a receptive a gradual development of the present phase of the mind. He has observed long phyla in which characters theory entertained by the so called American School. appear, not fortuitously, so far as we can see, but determinately, in the place where they will at some future Osborn in an address before the American Society of stage do the most good to the animal. He has observed Naturalists in New Haven in 1906 described what he such characters or structures appear as useless called the four inseparable factors in evolution— rudiments, persist as such during the life of the individual Ontogeny, Heredity, Environment and Selection. He and gradually develop to usefulness during the life of the expressed these in the formula O x H x E x S in which race. He has observed these rudiments rise and the "x sign may be read "influenced by and influencing." develop entirely removed from the influence of the We may review Osborns paper as a convenient way of environment.
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