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Introduced species can have diverse effects on recipient ecosystems. Here we share observations suggesting the formation of a reciprocally positive interaction, seed dispersal, between an introduced lizard and a native palm. We present evidence that the large arboreal lizard ( Anolis equestris ), native to the West Indies but well-established in south Florida USA, has a diet dominated by the fruit of several native trees including the endangered royal palm ( Roystonea regia ). We also show that seeds passed through the gut of A. equestris are viable, suggesting their role as seed dispersers in their introduced range. These findings are the first to document the passage of viable seeds by Anolis lizards, a speciose and ecologically-diverse Neotropical group that exhibits widespread frugivory. We believe these observations highlight potentially important, but understudied interactions between these Neotropical lizards and plants.

The curious habit of shingle-leaf climbers – root-climbing plants whose leaves are closely adpressed to the phorophyte and often overlap like shingles – has attracted the attention of both botanists and horticulturists for more than a century. The habit has arisen in ten families, 22 genera, and at least 158 species and is especially common in several genera of Araceae and Marcgravia (Marcgraviaceae). Herein, the species are tabulated, and various hypotheses for the evolution of the habit are reviewed. Two hypotheses that emerge as having explanatory power for understory shingle-leaf climbers are 1) Trapping & Recycling CO2 and 2) Stemflow Nutrient Capture, but other hypotheses may also have support in some cases. Three hypotheses (Balancing Carbon Allocation, Avoiding Damage from Falling Objects, and Avoiding Herbivory) have some support for some species. One hypothesis (Protecting against Desiccation of Roots and Leaves) has some support for shingle-leaf climbers in exposed, sunny habitats (viz., Hoya, Dischidia, Cattleya cernua and other orchids). Different selective pressures may have led to convergence on the shingle-leaf habit in different habitats. Moreover, these hypotheses are not necessarily mutually exclusive. Few hypotheses have been explicitly tested, and so the adaptive significance of the shingle-leaf climber habit remains uncertain.

We surveyed leaf material of 545 individual palms representing 108 genera and 155 species for cyanogenesis using the Feigl-Anger test. We detected HCN production in only two species of one genus, Drymophloeus. Additional smaller surveys of shoot meristems and roots revealed cyanogenesis only in the shoot meristem of one species of Dypsis. Our results indicate that cyanogenesis is rather rare in the family. ( 2000 Elsevier Science Ltd. All rights reserved.