DNA

A great shame of creationism and intelligent design is their appropriation and mischaracterization of genuine scientific concerns about whether we currently possess a complete explanation for the unity and diversity of life. Explore Evolution thoroughly mixes up scientific issues of gene-centric vs. epigenetic phenomena with much broader unsupported anti-evolutionary claims that genes do not control development and that new body plans need new sets of non-genetic instructions.

The success of developmental genetics in identifying an evolutionarily conserved set of genes that are used to construct organisms can lead to the temptation of restricting explanation of morphological evolution to genes alone. The question of whether nuclear genes were responsible for embryonic development has a long history. In the first half of the 20th century, proponents of nuclear inheritance battled with advocates of cytoplasmic inheritance. More recent authors argue that the metaphor of a genetic program does not take into consideration environmental affects upon development. Some argue that genes alone cannot explain cellular organization in microbes; that self-organizing properties of sub-cellular structures operating in physically constrained environments are also important. Others suggest that physical forces acting upon the earliest multi-cellular organisms played a major role in morphological evolution. A growing body of research indicates that the emergent properties of gene networks and cellular behaviors are also important for explaining morphological evolution. Other research suggests that development does not have the goal of producing an adult form and that the role of genes in regulating animal development is presently overemphasized.

Explore Evolution caricatures the nature of these scientific critiques of a gene-centric biology. Explore Evolution concludes that something else some other source of information besides DNA is necessary to construct an organism and therefore evolution of body plans could not have resulted from mutations. Explore Evolution hints that the something else is still a mystery. They should have described to students how non-genetic processes (such as biomechanical forces and exploratory behavior of cells) contribute to morphological evolution.

Neil DeGrasse Tyson, the Director of the Hayden Planetarium at the American Museum of Natural History has described intelligent design as "a philosophy of ignorance" and his description is exemplified in this section of Explore Evolution.

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