Re: native North American aroids
In a message dated 12/09/1999 8:41:05 AM Pacific Standard Time,
> Since that time, this species has colonized a fairly substantial
> area of northern South America, the Caribbean Islands, most of Florida and
> the gulf coastal states where the winter temperatures don't get cold
> to freeze the ground. There is also a species of Bulbophyllum which has
> apparently managed the migration (the only African member of an otherwise
> Asian orchid genus). If orchids can do, its not hard to imagine aroids
> managing the same feat.
So the question, then, is how small/lightweight are Pistia seeds? Orchid
seeds are like dust, easily carried on the atmosphere. Are Pistia seeds
similar? Alternatively, it may be possible for Pistia to cross the ocean on
flotsam carried by the Equatorial Current (which runs from Africa to South
America). Or, since the cattle egret is known to have crossed the Atlantic
in recent years, could there have been a bird-assisted dispersal?