Micromechanics in biogenic hydrated silica: Hinges and interlocking devices in diatoms

Abstract

Diatoms are single-celled organisms with rigid parts in relative motion at the micrometre scale and below. These biogenic hydrated silica structures have elaborate shapes, interlocking devices, and, in some cases, hinged structures. The silica shells of the diatoms experience various forces from the environment and also from the cell itself when it grows and divides, and the form of these micromechanical parts has been evolutionarily optimized during the last 150 million years or more, achieving mechanical stability. Linking structures of several diatom species such as Aulacoseira, Corethron, and Ellerbeckia are presented in high-resolution SEM images and their structure and presumed functions are correlated. Currently, the industry for micro-and nanoelectromechanical devices (MEMS and NEMS) puts great effort into investigating tribology on the micro-and nanometre scale. It is suggested that micro-and nanotribologists meet with diatomists to discuss future common research attempts regarding biomimetic ideas and approaches for novel and/or improved MEMS and NEMS with optimized tribological properties.

Exploring the Innovational Potential of Biomimetics for Novel 3D MEMS

“…MEMS developers interested in including the bioinspired approaches presented in this work have been identified and as next step bioinspired 3D MEMS will be designed and modelled and prototypes will be constructed. Corethron pennatum, Corethron criophilum [12] obtain 3D structures from fabricated 2D structures Springs … reversibly store mechanical energy?…”

Rutilariaceae redefined: a review of fossil bipolar diatom genera with centrally positioned linking structures, with implications for the origin of pennate diatoms

“…Some confusion in the literature (e.g. Olney et al, 2005;Gebeshuber & Crawford, 2006;Girard et al, 2009) is caused by references to Syndetocystis (Greville, 1866) and Syndetoneis (Grunow, 1888), which, although initially regarded as separate genera, were shown to be synonyms of Rutilaria by Ross (1995; see also Ross & Sims, 1974).…”

“…Ocelli are located on the distal faces of polar elevations (Figs 23,27 and 30), and a periplekton is always located in the centre of the valve (Figs 22,24 and 28). The periplekton provides a rigid inseparable link, but in some cases would enable relative rotation of cells by up to 90 and also a relative movement between sibling cells along the pervalvar axis (Gebeshuber & Crawford, 2006;Crawford & Sims, 2008), depending on the length of the periplekton caulis. In some species, there is a row of T-shaped, branching or spathulate marginal spines, which can provide an additional link between sibling valves (Figs 21 and 18c).…”

Trochosira polychaeta: a colonial diatom from the late Cretaceous exhibiting two contrasting chain-linking mechanisms and a wide range of preservation

“…Mechanisms of chain formation in Cretaceous diatoms included central and marginal linking structures (Witkowski et al, 2011) although subsequent evolution through the Cenozoic appears to have favoured linkage by the marginal spines or processes that are common in modern chain--forming species (Gebeshuber & Crawford, 2006;Crawford and Sims, 2008).…”