Rock figs of Mexico are considered a type of strangler fig. Tropical strangler figs seedlings start out as an epiphyte high on the branches of host tree. They eventually send anastomosing, aerial roots to the ground, completely enveloping the host tree. The following paragraph is from my Strangler Figs & Banyan article on Wayne's Word:

In their native tropical habitats, many figs are called "stranglers." Seeds germinate high on the moist branches of rain forest trees, sending numerous aerial roots to the ground. The sticky seeds are dispersed by a variety of fruit-eating birds and bats. Like botanical boa constrictors the serpentine roots gradually wrap around the host's limbs and trunk, crushing the bark and constricting vital phloem and cambial layers. The network of roots, resembling a tangle of writhing snakes, also fuse together (anastomose) forming a massive woody envelope or "straightjacket" encircling the host. Expansion of the host trunk as it grows in girth may accentuate the death grip and subsequent girdling process. Eventually the host tree dies of strangulation and shading, and the strangler fig stands in its place. In many cases the host tree may actually succumb from shading and root competition rather than strangulation. When strangler figs start in the ground, as in cultivation, their trunks develop from the ground upward like other "conventional" trees.

In the Cape Region of Baja California there are many palapas, traditional Mexican roofed structures supported by a palm trunk. They are common on beaches with a roof made from palm leaves or branches. The palm trunks are often encircled by a strangler fig resembling a botanical boa constrictor. Palm beams with strangler figs are also used indoors. In Central America, strangler figs are referred to as "matapalo" (tree-killer). The palm trunks are undoubtedly imported from the mainland, probably a tropical region.

The above syconium is from the monoecious Ficus petiolaris in Palomar College Arboretum. F. palmeri and F. brandegeei are synonyms of F. petiolaris. The syconium contains both male and female flowers according to above illustration. Pollination did not occur because the symbiotic pollinator wasp (Pegoscapus) is not present. Consequently, no seeds were produced and all the syconia fell from branches and littered ground beneath tree. Monoecious is technically a species term. I suppose you say the syconium is "bisexual." About half of the world's 800+ fig species are monoecious, the other half being dioecious with separate male and female trees. Monoecious figs are considered to be the ancestral breeding system, dating back 70 million years when T-Rex walked on this planet.

In the dioecious, common edible fig (Ficus carica) there is a persistent allele (P) that allows unpollinated syconia to remain on the tree and become fleshy and flavorful. In fact, there are about 500 varieties with this persistent trait. Of course, without pollination the syconium does not contain seeds. The mutant, persistent gene is not advantageous to female fig trees, but it is a boon to fig growers because they get crops of tasty figs without the symbiotic fig wasp (Blastophaga psenes). Most fig connoisseurs agree that wasp-pollinated figs, with pollen from the male caprifig, are the best tasting. The seeds impart a delicious nutty flavor to the ripe syconium. In fact, a cutting from my remarkable 'Vista Caprifig' now grows near the Performing Arts Center on campus. Details of persistence and fig sexuality are explained on my fig page that is cited in many fig references.

The general growth habit of this endemic species is very similar to F. petiolaris. Its leaves, branchlets and syconia are glabrous; however, in F. palmeri these structures are minutely pubescent (fuzzy). I always thought F. petiolaris was a mainland species east of the Gulf of California. Problem finally solved: They are all F. petiolaris!

On my trip to the Sierra de la Giganta with Steve Disparti, I labeled our herbarium specimen Ficus brandegeei because it seemed to fit that species in the classic Flora of Baja California by Ira L. Wiggins; however, a type specimen (holotype) collected in 1817 is labeled F. petiolaris. During the past century, several names have been assigned to this fascinating fig, including F. petiolaris, F. palmeri and F. brandegeei. In fact, some authors have listed the latter 2 species as subspecies of F. petiolaris. The current taxonomic consensus is that they are all the same variable species of the 1817 binomial. The following is our herbarium sheet at the San Diego Natural History Museum compared with the original type specimen at the National Museum of Natural History in Paris, France:

Ficus petiolaris

Ficus palmeri

Ficus palmeri

Baja California began to separate from mainland Mexico about 8-10 million years ago. The disjunct distribution of rock figs Ficus petiolaris is undoubtedly explained by its widespread distribution on the continent of Mexico, from which the Baja California peninsula "drifted."