Tag Archives: mollusc

Molluscan spikes explained by physical properties of the growing mantle!


That paper might interest some of you

Mechanical basis of morphogenesis and convergent
evolution of spiny seashells
Régis Chirat, Derek E. Moultonb, and Alain Goriely


Convergent evolution is a phenomenon whereby similar traits
evolved independently in not closely related species, and is often
interpreted in functional terms. Spines in mollusk seashells are
classically interpreted as having repeatedly evolved as a defense in
response to shell-crushing predators. Here we consider the morphogenetic
process that shapes these structures and underlies their
repeated emergence. We develop a mathematical model for spine
morphogenesis based on the mechanical interaction between the
secreting mantle edge and the calcified shell edge to which the
mantle adheres during shell growth. It is demonstrated that a large
diversity of spine structures can be accounted for through small
variations in control parameters of this natural mechanical process.
This physical mechanism suggests that convergent evolution of
spines can be understood through a generic morphogenetic process,
and provides unique perspectives in understanding the phenotypic
evolution of this second largest phylum in the animal kingdom.