Thus, gradual changes in leaf shape in species of, for example, the fern genus Matonia (Matoniaceae) are described as heteroblastic
(Kato & Setoguchi, 1998) but they occur change along the same axis.
This hypothesis is supported by the ontogenetic changes in leaf anatomy observed in the more heteroblastic
Eucalyptus species, which shift from soft juvenile leaves with loosely packed cells to leathery adult leaves with tightly packed cells (Johnson 1926, Penfold and Willis 1961, Cameron 1970).
leaf development in Acacia: Morphological and morphogenetic implications.
when it comes to the use of the terms heteroblastic
The three different measures of developmental stability used in this study (within-plant variance in leaf length, variance around a heteroblastic
pattern, and FA) all showed a trend for the selfing, more homozygous populations to be less developmentally stable.
Trees can show small, gradual changes from juvenile to mature states (homoblastic), or they can exhibit an abrupt transition (heteroblastic
), as found in Quercus, Robinia, and Eucalyptus.
The difference in leaf blade shapes produced at different phases of ontogeny indicates that sororia is heteroblastic
, meaning that these differences in blade shape are genetically programmed changes in shoot components that occur as a normal expression of the plant's ontogeny (Goebel, 1900; Allsopp, 1965, 1967; Kaplan, 1973).
For example, heterophylly in pteridosperms may be an expression of heteroblastic
development in which the smaller fronds may have come from juvenile plants.
radicans is thus a vine of the type described by Lee and Richards (1991) in which heteroblastic
changes occur as branches without adventitious roots extend away from the juvenile form's support.
Similar results have been found in Pseudopanax crassifolius (Araliaceae), a heteroblastic
tree, in which leaf size and shape differ greatly between juvenile and mature shoots.
In both Alismatales and Nymphaeales there is a remarkably similar heteroblastic
progression of linear to laminar to broadly ovate or peltate leaves.