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Crystals: animal, vegetable or mineral?

Hyde ST - Interface Focus (2015)

Bottom Line: The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries.The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter.In addition to the philosophical relevance of this perspective, there are important ramifications for science.

View Article: PubMed Central - PubMed

Affiliation: Department of Applied Mathematics, Research School of Physics and Engineering , The Australian National University , Canberra, Australian Capital Territory 0200 , Australia.

ABSTRACT
The morphologies of biological materials, from body shapes to membranes within cells, are typically curvaceous and flexible, in contrast to the angular, facetted shapes of inorganic matter. An alternative dichotomy has it that biomolecules typically assemble into aperiodic structures in vivo, in contrast to inorganic crystals. This paper explores the evolution of our understanding of structures across the spectrum of materials, from living to inanimate, driven by those naive beliefs, with particular focus on the development of crystallography in materials science and biology. The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries. Our current understanding, driven largely by detailed exploration of biomolecular structures at the sub-cellular level initiated by Bernal and Astbury in the 1930s, and more recent explorations of sterile soft matter, makes it clear that this is a false dichotomy. For example, liquid crystals and other soft materials are common to both living and inanimate materials. The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter. In addition to the philosophical relevance of this perspective, there are important ramifications for science. For example, the debates surrounding extra-terrestrial life, the oldest terrestrial fossils and consequent dating of the emergence of life on the Earth rests to some degree on prejudices inferred from the supposed dichotomy between life-forms and the rest.

No MeSH data available.


Related in: MedlinePlus

(a) NASA's scanning electron micrograph of a fragment of the Martian meteorite, ALH84001, collected in Antarctica. The boxed area shows a segmented structure that resembles a (highly shrunken) bacterium from the meteorite. (Scale bar, 100 µm; estimated from [63]). (b) Scanning electron micrographs of silica-barium carbonate ‘biomorphs' grown in the laboratory under sterile conditions. (Scale bar, 30 µm. Image courtesy of Anna Carnerup).
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RSFS20150027F8: (a) NASA's scanning electron micrograph of a fragment of the Martian meteorite, ALH84001, collected in Antarctica. The boxed area shows a segmented structure that resembles a (highly shrunken) bacterium from the meteorite. (Scale bar, 100 µm; estimated from [63]). (b) Scanning electron micrographs of silica-barium carbonate ‘biomorphs' grown in the laboratory under sterile conditions. (Scale bar, 30 µm. Image courtesy of Anna Carnerup).

Mentions: In 1996, NASA triumphantly suggested that they had found the ‘smoking gun’ that demonstrated extra-terrestrial life, namely the presence of bacterial remains within a meteorite dislodged from Mars, and collected in Antarctica [63]. The announcement was met with massive interest, so profound that President Clinton appeared on TV to discuss the finding [64]. The excitement was triggered by a scanning electron micrograph that revealed a curvilinear, segmented shell (figure 8a), similar to the shapes of modern filamentous bacteria, and to the forms found in Archaean rocks from northwestern Australia, and believed to be fossilized bacteria.Figure 8.


Crystals: animal, vegetable or mineral?

Hyde ST - Interface Focus (2015)

(a) NASA's scanning electron micrograph of a fragment of the Martian meteorite, ALH84001, collected in Antarctica. The boxed area shows a segmented structure that resembles a (highly shrunken) bacterium from the meteorite. (Scale bar, 100 µm; estimated from [63]). (b) Scanning electron micrographs of silica-barium carbonate ‘biomorphs' grown in the laboratory under sterile conditions. (Scale bar, 30 µm. Image courtesy of Anna Carnerup).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4590423&req=5

RSFS20150027F8: (a) NASA's scanning electron micrograph of a fragment of the Martian meteorite, ALH84001, collected in Antarctica. The boxed area shows a segmented structure that resembles a (highly shrunken) bacterium from the meteorite. (Scale bar, 100 µm; estimated from [63]). (b) Scanning electron micrographs of silica-barium carbonate ‘biomorphs' grown in the laboratory under sterile conditions. (Scale bar, 30 µm. Image courtesy of Anna Carnerup).
Mentions: In 1996, NASA triumphantly suggested that they had found the ‘smoking gun’ that demonstrated extra-terrestrial life, namely the presence of bacterial remains within a meteorite dislodged from Mars, and collected in Antarctica [63]. The announcement was met with massive interest, so profound that President Clinton appeared on TV to discuss the finding [64]. The excitement was triggered by a scanning electron micrograph that revealed a curvilinear, segmented shell (figure 8a), similar to the shapes of modern filamentous bacteria, and to the forms found in Archaean rocks from northwestern Australia, and believed to be fossilized bacteria.Figure 8.

Bottom Line: The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries.The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter.In addition to the philosophical relevance of this perspective, there are important ramifications for science.

View Article: PubMed Central - PubMed

Affiliation: Department of Applied Mathematics, Research School of Physics and Engineering , The Australian National University , Canberra, Australian Capital Territory 0200 , Australia.

ABSTRACT
The morphologies of biological materials, from body shapes to membranes within cells, are typically curvaceous and flexible, in contrast to the angular, facetted shapes of inorganic matter. An alternative dichotomy has it that biomolecules typically assemble into aperiodic structures in vivo, in contrast to inorganic crystals. This paper explores the evolution of our understanding of structures across the spectrum of materials, from living to inanimate, driven by those naive beliefs, with particular focus on the development of crystallography in materials science and biology. The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries. Our current understanding, driven largely by detailed exploration of biomolecular structures at the sub-cellular level initiated by Bernal and Astbury in the 1930s, and more recent explorations of sterile soft matter, makes it clear that this is a false dichotomy. For example, liquid crystals and other soft materials are common to both living and inanimate materials. The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter. In addition to the philosophical relevance of this perspective, there are important ramifications for science. For example, the debates surrounding extra-terrestrial life, the oldest terrestrial fossils and consequent dating of the emergence of life on the Earth rests to some degree on prejudices inferred from the supposed dichotomy between life-forms and the rest.

No MeSH data available.


Related in: MedlinePlus