Abstract Detail

Reproductive Processes

Muchhala, Nathan [1], Moreira Hernandez, Juan [2], Zuluaga Trochez, Alejandro [3].

The Long Stems Characteristic of Bat-Pollinated Flowers Greatly Reduce Bat Search Times while Foraging.

Botanists have long noted that flowers adapted to bat pollination tend to be particularly well-exposed, with long stems that position them away from other foliage.  The selective advantage of this trait, however, has remained obscure.  We captured nectar-feeding bats (Anoura caudifer) in cloud forests of the Colombian Andes and held them in flight cages to test the effects of floral exposure on foraging behavior.  Ten bats were held for 3 days each, and in a series of trials we timed how long it took to locate a flower (of Burmeistera succulenta) affixed to one of six poles placed in the cage.  Bats were exposed to four treatments: long or short floral stems, in either simple or complex backgrounds.  Complex backgrounds included arrays of leaves around each pole, while simple had none.  Flowers were randomly shifted after each trial so that bats did not simply learn location.  In simple backgrounds, bats showed no difference in search times for long vs. short stems, while in complex backgrounds, bats took nearly twice as long to locate short-stemmed flowers.  This suggests that increased flower exposure allows bat echolocation to better distinguish floral echoes from background clutter echoes.  This, in turn, would favor the evolution of long stems to ensure that flowers are discovered by bats and thus can successfully reproduce.

1 - University Of Missouri - St. Louis, Biology Dept., R223 Research Hall, One University Blvd, One University Blvd, St. Louis, MO, 63121, United States
2 - University Of Missouri-St. Louis, R223 Research Hall, One University Boulevard, St. Louis, MO, 63121, United States
3 - Universidad del Valle, Departamento de Biología, Cali, Colombia

Keywords:
pollination
Chiropterophily
Campanulaceae
Nectarivory
Echolocation
Burmeistera.

Presentation Type: Oral Paper
Session: REP4, Reproductive Processes 4
Location: Virtual/Virtual
Date: Thursday, July 30th, 2020
Time: 4:30 PM
Number: REP4007
Abstract ID:407
Candidate for Awards:None