Progenesis
produced by negative allometry & early offset


    Timing of metamorphosis in ascidian Tunicates is size-dependant (B on vertical axis).  If sexual maturity is achieved at an smaller size (B B', projected on vertical axis), functional gonads will develop prior to metamorphosis (green bar on horizontal axis). This produces a motile, larval-like adult with functional gonads, similar to the model for the earliest proto-chordates.


Text material © 2024 by Steven M. Carr