Web Special
The Holly Family

The hollies, both deciduous and evergreen, constitute a worldwide genus of approximately 400 temperate and tropical species, distributed mostly in East Asia, South America, and eastern North America. Only a handful of species is European. All belong to the genus Ilex, which is now considered the sole genus in the holly family (Aquifoliaceae).

The evolutionary trail of the hollies is somewhat obscure, but recent research suggests that they likely have a primordial pedigree. Holly pollen has been identified in 100-million-year-old sediments in southeastern Australia and some experts suspect that at least one ancient holly lineage may have enjoyed a worldwide distribution even then. Others suggest that this early lineage may have died out completely, and that today's species may be much younger, perhaps originating again a mere 40 to 60 million years ago.

The geographic origin of the genus Ilex is not fully understood. But the prognostications are fascinating. Some experts hold that North America and East Asia may have been the starting points for the modern lineage, with subsequent migrations to South America. One theory postulates an eastward expansion by the trans-Pacific dispersal of Asian seeds by birds. Another suggests that they may have moved over land along the three-million-year-old land bridge that still connects the American continents.

Molecular data suggest with fair certainty that there are two lineages of the genus in South America - one with affinities to North America and the other with affinities to Asia. Whether this means that the forerunners of today's plants arose in the Southern Hemisphere and radiated northward, or in the Northern Hemisphere and radiated southward, or in Asia with migration first to North America and then to South America, is still conjectural.

by Gil Nelson.