Could any “useless” natural object composed of simple materials exceed the beauty of a snow crystal? As you wish for a white Christmas, think about two snowflake designers: one who makes them in a lab, and one who makes them in clouds.
Kepler’s snowflakes: Six-sided snowflake crystals have been known by everyone with sharp eyes living where snow falls – the Chinese who wrote about them in the 2nd century, Albert Magnus who described them in the 13th century. But the first to really discuss their structure and origins in a scientific way was Johannes Kepler. Philip Ball wrote about this in Nature this week (Vol. 480, 22 December 2011, p. 455, doi:10.1038/480455a). The sight of a snowflake on his lapel provoked the great German astronomer to ponder their construction. His short 1611 booklet, De nive sexangula (On the Six-Cornered Snowflake) “seeded the notion from which all of crystallography blossomed: that the geometric shapes of crystals can be explained in terms of the packing of their constituent particles.” Kepler imagined that a snowflake was composed of constituent particles (“not explicitly atoms, but as good as,” Ball remarks) whose packing led to the emergent geometric structure. Elegant as this beginning of a theory was, Kepler was unable to explain the plate-like shape and hexagonal ornamentation:
Kepler instead fell back on Neoplatonic occult forces. God, he suggests, has imbued the water vapour with a “formative faculty” that guides its form. There is no apparent purpose to the flake’s shape, he observes: the “formative reason” must be purely aesthetic or frivolous, nature being “in the habit of playing with the passing moment”. That delightful image, which touches on the late Renaissance debate about nature’s autonomy, remains resonant today in questions about the adaptive value (or not) of some complex patterns and forms in biological growth.
Ball does not discount the genius of the otherwise influential Kepler, “for not until the 1980s was this seen to be a consequence of branching growth instabilities biased by the hexagonal crystal symmetry of ice.” In fact, Kepler’s tentative foray into crystallographic principles proved a good heuristic for researchers who followed him.
Libbrecht’s snowflakes: The modern master of snowflake photography today is Kenneth Libbrecht of Caltech. His collection is not only vast (10,000 and growing), but stunningly beautiful (see his SnowCrystals.com Caltech website for a tour). As a physicist, Libbrecht brings the quest for scientific explanation to his famous hobby. Yes, he does believe that no two snowflakes are alike. Though much has been explained in his lab experiments, where he can grow snowflake-like crystals under controlled conditions, he admits much remains to be learned. Jascha Hoffman interviewed him for Nature (Vol. 480, 22 December 2011, pp. 453–454, doi:10.1038/480453a). He asked why Libbrecht studies snowflakes.
We see these beautiful structures falling from the sky, and we still cannot explain how they came to be. When you ask how snowflakes form, you are really asking about how molecules go from a disordered gaseous state to an ordered crystalline lattice. Unexpected phenomena can emerge — snowflakes are one fascinating example. The complex morphologies arise in part because different ice surfaces grow at different rates. What we learn could eventually find application in materials science or nanoscale self-assembly. But I am also motivated to simply understand how this natural phenomenon works.
Libbrecht described how the six sides grow nearly identically because as the flakes fall through the clouds, they are exposed to the exact same conditions of temperature and humidity. The shape of the flakes (“hollow columns, needles, bullet rosettes, stellar dendrites, sectored plates, 12-branched stars, triangular crystals and many more”) are sensitive to temperature – something known for 75 years. “But the origin of this odd behaviour is still not known, so I am working hard to solve this puzzle,” he said. He has traveled the world in his quest, and taken the art of snowflake photography, begun by Wilson Bentley in the 1880s, to new heights.
Intelligent design theory concerns “certain features of the universe and of living things [that] are best explained by an intelligent cause, not an undirected process such as natural selection” (IntelligentDesign.org). ID advocates differentiate between phenomena that have random causes, natural law causes, and intelligent causes. A snowflake obeys the laws of physics, and as such, does not convey a function or message – as would skywriting or the DNA code. Snowflakes are examples of natural phenomena that show emergent patterns based on natural law and the randomness each flake experiences falling through the winds and clouds. The laws dictate the six-sided pattern, but not the result – a snowflake that is unique in the universe. There is no “message” or function in a crystal; snow could just as well be composed of shapeless blobs of H20 crystals (like man-made snow), and would still water the earth. Design theorists are, therefore, drawn to phenomena that convey messages, like codes as opposed to repetitive patterns. The inference to design in snowflakes comes from higher, philosophical levels: (1) the origin of laws of nature that allow for these patterns, and (2) the “useless beauty” (aesthetics) that draws our minds to appreciate them.
We began by promising stories of two snowflake designers. One was Libbrecht, but the other was not Kepler. Hint: “Have you entered the storehouses of the snow, or have you seen the storehouses of the hail?” (Job 38:22). A good visual resource on snowflakes, including some of Libbrecht’s most stunning photos, can be found in the beautiful film God of Wonders. It explains why the beauty and design of snowflakes points to design in nature beyond what is needed for mere survival. Man is the only earthly creature endowed with the capacity to appreciate beauty. Yes, snow crystals obey natural laws, but they point man to the Lawgiver, and provide insight into His attributes of power, wisdom, and love.