Interactions between mammals and fruit of an endemic tree (Amphitecna montana, Bignoniaceae) with megafauna traits.

Several features in the fruit of some neotropical trees likely evolved in response to the interaction with the mammalian megafauna extinct in the late Pleistocene. However, few studies have assessed the interactions between these plants and mammals in the absence of megafauna. We conducted a camera-trapping study in the Reserve of El Triunfo, Chiapas, Southern Mexico, to record the fauna consuming the fruit of the endemic tree Amphitecna montana which has megafauna traits. We surveyed the abundance and the spatial distribution of trees, saplings, and seedlings in 10 transects totalizing 0.1 ha, analyzed the chemical composition of their fruit, and assessed the impact of seed manipulation on germination success and seedling establishment. We recorded 12 species of medium-large mammals but the most frequent consumers of fruit were squirrels. The relationship among trees, saplings, and seedlings did not indicate the existence of a regeneration limitation. All the plant stages showed a clustered spatial pattern, which is in agreement with squirrels being the main seed dispersers. Free seeds were the more successful to germinate and establish as seedlings. Despite the current lack of megafauna in our study area, the A. montana population does not show signs of declining. [ABSTRACT FROM AUTHOR]