Salient theories in the fossil debate in the early Royal Society

Deep questions about the nature of early-life signals: a commentary on Lister (1673) ‘A description of certain stones figured like plants’

“…During the seventeenth century, the plasticity of boundaries was being seriously explored, leading some to test whether ‘fool's gold’ (pyrite, iron sulfide) could be turned into metallic gold [ 12 ]. Interestingly, Martin Lister undertook experiments with pyrite [ 24 ] and was fascinated by its role in the formation of fossils [ 8 ]. Importantly for our story, the boundaries between inert minerals and living matter were also thought to be porous.…”

“…Both Ray and Lister had collaborated with Steno while at Montpellier in France in 1668. But while Ray had become an advocate for the ‘biogenic’ origin of fossils, Lister is now seen as either a confirmed sceptic [ 12 ] or as sitting on the fence, arguing that ‘fossils were not always the remains of living creatures’ [ 8 ]. As explored below, Lister's critical stance was arguably a prudent one for the time and remains so for modern debates about signals remote in time and space.…”

“…The deeper meaning of these fossils was further hinted at in a short postscript by John Ray [ 21 ]. This naturalist had collected similar fossil remains from Lindisfarne, and he may well have encouraged Lister to prepare a personal report [ 8 ]. Here, Ray recalls his earlier travels to Malta (in the steps of Steno), where he saw branched and stick-like fossils that resembled rock plants (possibly Thalassinoides crustacean burrows from the Miocene).…”

“…For Martin Lister in 1673, the null hypothesis was that his fossils formed by abiogenic, plastic forces within rock [ 8 ], as caricatured in figure 3 a . This was also the view of Kircher [ 13 ] and it prevailed for some decades afterwards, following the ideas of Oxford ‘chymist’ Robert Plot [ 8 , 37 ]. While Lister's choice of words shows that he was willing to play with the concept of petrified plants, he also found it much harder to accept the idea of fossilized animals.…”

“…Although Lister ( figure 1 a ) is now revered as an early expert on both mollusc shells and spiders [ 8 , 9 ], his historically important paper concerns what we would now recognize as the fossil remains of crinoids (‘sea lillies’; figure 1 c – g ), a largely extinct class of the phylum Echinodermata that also includes sea urchins and star fish. Interestingly, the animal fossils he puts before us were, at the time of writing, among the oldest known, being some 320–350 Myr old (Lower Carboniferous).…”