Some scholars have provided evidence about the specific adaptations (e.g., wing or pappus
) for dispersal of early colonizers [54-56].
Of course, students might prefer to use Pappus
' Dual Theorem.
Mature plants can produce more than 1000 flower heads with the potential to yield 25000 seeds with pappus
, which allows them major wind dispersal (Vigna and Lopez, 2008).
However, Descartes favors his algebra as more transparent (it provides clearer access to how the conclusion is generated), more general (since applicable to several kinds of problems) and heuristically more powerful (it allowed Descartes to find solutions to problems that had baffled ancient geometers such as Pappus
' four-line locus problem).
For instance, in his commentary on Book V of Ptolemy's Almagest, Pappus
of Alexandria gave a description of this instrument.
Should the hairy crown become wet at the time of its opening, the hydroscopic pappus
cannot spread apart the thistle-filaments needed to increase the disseminule's aerodynamic profile.
Species with pappi were anchored by pressing the seed tips in the sand, leaving most of the seed and the pappus