Just Wide of Lamarck

A profile of the eccentric French naturalist
Born into an aristocratic family as the youngest of eleven in 1744, Jean-Baptiste Lamarck had a fairly eclectic early life. Not wishing to pursue his […]

Art by Elizaveta Gelfreykh

Born into an aristocratic family as the youngest of eleven in 1744, Jean-Baptiste Lamarck had a fairly eclectic early life. Not wishing to pursue his father’s plans for him in the clergy, he soon abandoned his theological studies to follow his brothers into the French army.

The only accounts of Lamarck the soldier, written by his devoted daughter, somewhat predictably tell of a valiant and audacious young recruit. Medical complications soon ended his military career, and so Lamarck began his brief pursuits in medicine, music, and banking before the esteemed naturalist Georges Buffon encouraged him to persist with his interest in botany for long enough to publish his book Flore Française. The work was a meticulously prepared catalogue of French plant species, and became a standard resource for the botanical sciences. In researching the catalogue, Lamarck had overseen the doubling of recorded species of French flora. The publication constituted a fifth of known plant species—a significant contribution. It is these scientific exploits that saw Lamarck (undoubtedly assisted again by Buffon) elected to the prestigious Academie des Sciences, a platform which allowed him to willfully engage with the scientific community. Lamarck was a prolific thinker and dabbled widely in scientific discussion, publishing on the topics of atmospherics, meteorology, acoustics, planetary dynamics, geology, branching out as far as psychology and metaphysics, but most memorable is his treatise on evolution.

Widely accredited as the first fully formulated evolutionary theory, Philosophie Zoologique presented Lamarck’s hypotheses for the origin and development of species. The theory, which he formulated during his extensive cataloguing of invertebrates, was inspired by the similarities between organisms which led Lamarck to believe that species are interconnected.

In contrast to his mentor Buffon, who had earlier suggested that new species are a result of degeneration and simplification of earlier ones, Lamarck’s theory explained how evolution was caused by the effect of two forces; first, a ‘complexifying force’ which acts spontaneously to introduce new complex structures into creatures, and second, an ‘adaptive force’ which reinforced useful characteristics while causing disused ones to diminish and eventually disappear.

Lamarck believed that characteristics were acquired during an animal’s lifetime and could be passed on to its offspring. He reasoned, for example, that giraffes’ necks have lengthened as successive generations have stretched for higher and higher branches. Over time, these acquired characteristics would cause an organism’s descendants to become progressively more complex and better adapted to their environment. Lamarck initially realised that this implied that the world’s creatures thus made up a direct evolutionary lineage— they represented a continuous biological history of the world from the simplest organisms to the most advanced: humans. Lamarck struggled to try to reconstruct this lineage and eventually settled on the idea that would become central to evolutionary theory; that of a branching structure.

Lamarckian evolution, though widely discussed, did not become a generally accepted theory. This was in part due to a persistent lampooning from prominent zoologist Georges Cuvier. Cuvier’s enmity for Lamarck was such that, convinced that the falsehood of Lamarck’s theory was blindingly evident, Cuvier publicly suggested that Lamarck’s failing sight was due to his own principle of disuse.

With the hindsight of Darwin’s theory of evolution, it is easy to dismiss Lamarck simply as the man who got evolution wrong. However, this is a great discredit to a man who showed prowess as a soldier, musician, doctor, and most importantly, a naturalist. His contributions to the classification of species were staggering and it gave him great joy to be praised for it in his dying days. Even his theory of evolution, although no match for Darwin’s, attracted important peers including Robert Edmond Grant, the teacher of Charles Darwin himself. The posthumous remembrance Lamarck saw him become a hero figure in the history of French science, an attitude typified by one historian who wrote “Lamarck, like a secular saint…was the unknown soldier of truth”.

 

About Philip Crowley

Philip Crowley is a 3rd year undergraduate studying Physics at St. Hugh’s College.