Fossil bivalves and the sclerochronological reawakening

Abstract

The field of sclerochronology has long been known to paleobiologists. Yet, despite the central role of growth rate, age, and body size in questions related to macroevolution and evolutionary ecology, these types of studies and the data they produce have received only episodic attention from paleobiologists since the field's inception in the 1960s. It is time to reconsider their potential. Not only can sclerochronological data help to address long-standing questions in paleobiology, but they can also bring to light new questions that would otherwise have been impossible to address. For example, growth rate and life-span data, the very data afforded by chronological growth increments, are essential to answer questions related not only to heterochrony and hence evolutionary mechanisms, but also to body size and organism energetics across the Phanerozoic. While numerous fossil organisms have accretionary skeletons, bivalves offer perhaps one of the most tangible and intriguing pathways forward, because they exhibit clear, typically annual, growth increments and they include some of the longest-lived, non-colonial animals on the planet. In addition to their longevity, modern bivalves also show a latitudinal gradient of increasing life span and decreasing growth rate with latitude that might be related to the latitudinal diversity gradient. Is this a recently developed phenomenon or has it characterized much of the group's history? When and how did extreme longevity evolve in the Bivalvia? What insights can the growth increments of fossil bivalves provide about hypotheses for energetics through time? In spite of the relative ease with which the tools of sclerochronology can be applied to these questions, paleobiologists have been slow to adopt sclerochronological approaches. Here, we lay out an argument and the methods for a path forward in paleobiology that uses sclerochronology to answer some of our most pressing questions.

Astronomically controlled deep‐sea life in the Late Cretaceous reconstructed from ultra‐high‐resolution inoceramid shell archives

“…Thus, bivalve shells represent a remarkable biogeoarchive that allows one to analyse daily environmental changes over entire decades or centuries. These methods can be applied to fossil bivalve shells known from the Cambrian period onwards, providing insight into the development of bivalves throughout the Phanerozoic and constructing logs of environmental change over deep time in well‐preserved specimens (Moss et al, 2021). The recording of diurnal changes over a long period, spanning decades of shell growth, also allows one to analyse the recording of biological rhythms occurring in nature.…”

Tracing timing of growth in cultured molluscs using strontium spiking

“…Crystalline calcium carbonate is one of the most abundant marine biominerals and is produced by organisms ranging from microbes, coccolithophores, foraminifera and molluscs to corals and fishes (Crichton, 2019). Their fossil skeletons, shells and other biostructures are common in the archaeological and geological record because they preserve relatively well and therefore play an important role as archives for past climates (Lough and Barnes, 2000;Pages 2k consortium, 2017;Henkes et al, 2018;Marchegiano et al, 2019;Moss et al, 2021;Agterhuis et al, 2022) and environments (Sampei et al, 2005;Song et al, 2014;Auderset et al, 2022). Carbonate skeletons also preserve information about life histories (Gerringer et al, 2018;Mat et al, 2020;Posenato et al, 2022), ecological relationships between organisms (Fagerstrom, 1987;Mourguiart and Carbonel, 1994;Valchev, 2003), and past human interrelations (Gutieŕrez-Zugasti, 2011;Haour et al, 2016;Burchell et al, 2018).…”

Parameter Estimation and Model Selection for Stochastic Differential Equations for Biological Growth

“…The main motivation for this work comes from problems where it is necessary to fit SDEs to modeling growth biological data; for instance in marine biology, ecology (see [8]), oncology (see [18], or in paleontology (to model sclerochronological parameters of shell growth [16]). Given that real systems cannot be completely isolated from their environments and, therefore, always experience external stochastic forces, then the use of SDEs as models is justified and preferred to (ODEs).…”