They are unusual in that the rachis, or midrib, of the frond is thin, flexible, and long, the frond unrolling with indeterminate growth and the rachis twining around supports, so that each frond forms a distinct vine.
12.
The broad topic would come under Life _ history _ theory, See e . g . here for ( freely accessible ) research discussing why indeterminate growth occurs in animals, and how it's tied to resource allocation and impacts of life-history strategies . talk ) 14 : 35, 22 July 2015 ( UTC)
13.
Colonies, in the context of development, may be composed of two or more unitary ( or solitary ) organisms or be modular organisms . "'Unitary organisms "'have determinate development ( set life stages ) from zygote to adult form and individuals or groups of individuals ( colonies ) are visually distinct . "'Modular organisms "'have indeterminate growth forms ( life stages not set ) through repeated iteration of genetically identical modules ( or individuals ), and it can be difficult to distinguish between the colony as a whole and the modules within.
