  The presence of a dynamical scalar field in the early universe could
significantly affect the `freeze-out' time of particle species. In particular,
it was recently shown that an enhancement of the relic abundance of neutralinos
can be produced in this way. We examine under which conditions this primordial
scalar field could be identified with the Quintessence scalar and find, through
concrete examples, that modifications to the standard paradigm are necessary.
We discuss two possible cases: the presence of more scalars and the switching
on of an interaction.
