World of Wonders

When we see things that aren’t, we miss the wonderful things that are.

Lamarck is Alive and Well and Living in Language

On the 266th anniversary of the birth of Jean Baptiste Pierre Antoine de Monet, Chevalier de Lamarck, Lamarckism is alive and well, and living in the language we use to describe the evolution of species.

Lamarck

Long before the English naturalist Darwin set sail for the Galapagos Islands, the French biologist Lamarck proposed his own theory of evolution. According to the Chevalier, species did indeed evolve—and as Richard Dawkins writes in The Blind Watchmaker, he deserves to be honoured for this accomplishment alone. Furthermore, Lamarck said, species were transformed by forces that guided each individual creature toward complexity and toward a greater degree of adaptation to their environment.

The mechanism behind this transformation was twofold: the use and dis-use of certain organs, which led to the strengthening or weakening of those organs over the course of a creature’s life; and the inheritance of those newly acquired or discarded characteristics by the animal’s immediate offspring.

According to Lamarckism, an animal responded to the “felt needs” demanded by its habitat and modified its form accordingly. For example, an elephant-like creature responded to colder temperatures by growing a thicker coat—the way we would put on a heavier winter parka. A small boreal mammal stretched the skin between its long claws gliding from tree to tree. Each individual then passed on the modification—the acquired trait—to its offspring. After enough generations, new species emerged: the woolly mammoth, bat, and so on.

800px-Wooly_Mammoth-RBC

Following the publication of On the Origin of Species, a century and a half of evidence proved that Darwin was right and Lamarck wrong. Species evolve through natural selection: natural, random variations in species increase the survivability of individuals with that variation; those individuals leave more offspring who in turn leave more offspring themselves; and, thus, a new species emerges.

Lamarck’s unexplained forces toward greater complexity and adaptability remained ill-defined and outside the realm of empirical biology. No mechanism was ever identified to explain how acquired characteristics like modified hair or skin could be encoded into a creature’s DNA during its lifetime, in order to be passed on to the next generation—and the theory eventually disappeared.

And yet, nearly three centuries after his birth, we describe evolution with language that more closely suggests Lamarck’s idea than Darwin’s. We write that “snakes modified their lungs—one lung has been slimmed and elongated and the other reduced to a functionless relic.” “Early reptile’s limbs lengthened and began to change position and point not sideways but downwards.” “Snakes finding themselves in new or changing habitats…may change physically, for instance, growing longer, shorter, stouter, or more slender, or their coloration may be modified to blend in with the new habitat.” “They (insects) can transform their bodies to meet every purpose.”

The verbs conjure images of individual creatures modifying their forms over the course of their lifetimes, making them more adapted their environments.

In a recent article about Pacific coconut crabs, the author wrote that “…the juveniles develop in the sea for about a month, after which they head out onto land.” In the very next paragraph, he writes that “coconut crabs have developed organs called branchiostegal lungs.” In successive paragraphs, the verb “develop” has entirely different meanings.

Of course, when we write, “…lizards took to the water and developed slimmer bodies and smaller legs until they became snakes”, we mean that the more snake-like individuals in a population of marine lizards had an advantage over the rest of their cohort and as a result, left more offspring, eventually leading to today’s snake species.

And of course, we science writers use these verbs as a form of shorthand when space doesn’t allow a more complete explanation, or when it is appropriate to a particular audience—and we will continue to do so.

Unfortunately, the language is not only an approximation, it hides the random, natural aspect of the process—the aspect that led Dawkins to describe natural selection as the “blind watchmaker.” Transitive verbs like “developed”, “transformed”, and “grew” conceal the true beauty and power of natural selection: from undirected variation and the increased survivability due to those variations emerge new “forms most beautiful and most wonderful.” The language withholds from readers a true appreciation of the wonder of Darwin’s idea.

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  1. […] of Wonders, Lamarck is Alive and Well Living in Language: “And yet, nearly three centuries after his birth, we describe evolution with language that […]

  2. […] another great article on Lamarck I recommend this https://chrissasaki.wordpress.com/2010/08/01/lamarck-is-alive-and-well-and-living-in-language/ , It’s quite interesting. Eco World Content From Across The Internet. Featured on […]

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