show Abstracthide AbstractThe primary goal of this study is to elucidate the key differences in gene expression between top(distal), middle(joint), and bottom(proximal) regions and of Erucaria erucarioides and Cakile lanceolata fruit.These fruits are dry elongated pods (siliques) with a unique morphology that enables two different seed dispersal methods in one fruit mediated by a central joint. The distal region of the fruit remains closed at maturity, and the bottom either opens or remains closed as in Erucaria or Cakile, respectively. The joint itself can also either abscise, as in Cakile, or remain attached like in Erucaria.Knowledge of gene expression within and between these species is informative about conservation or deviation from the known Arabidopsis valve margin (fruit dehiscence) pathway. Gene expression profiles will elucidate how related species alter the timing and location of gene expression to effect unique morphological variation.