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2 BATS AND FLOWERS WHY KATYDIDS IN 0 C IN AN EVOLUTIONARY RACE STOP THEIR SINGING A 0 LU N 8 D N ES UA -2 L R 0 E 0 PO R 9 WWW.BATCO N.ORG FALL 2009 T BBBAT CONSAAERVATIOTNT INTERNASS TIONAL BAinT thS e BBUUNNKKEERRSS Volume 27, No. 3, fall 2009 P.O. Box 162603 , Austin, Texas 78716 BATS (512) 327-9721 • Fax (512) 327-9724 FEATURES Publications Staff Director of Publications: Robert Locke Photo Editor: Meera Banta 1 Going to Great Lengths Graphic Artist: Jason Huerta Bats & flowers stage an evolutionary race Copyeditors: Angela England, Valerie Locke BATS welcomes queries from writers. Send your article pro - by Nathan Muchhala posal with a brief outline and a description of any photos to the address above or via email to: [email protected] . Members: Please send changes of address and all cor res - 4 Singing Bat Detectors pondence to the address above or via email to members@bat - con.org . Please include your label, if possible, and allow six Katydids know when to shut up weeks for the change of address. by Hannah ter Hofstede Founder/President Emeritus: Dr. Merlin D. Tuttle Board of Trustees: Executive Committee: 7 Bats along the Jordan River John D. Mitchell, Chair Bert Grantges, Secretary Military bunkers are becoming bat houses Marshall T. Steves, Jr., Treasurer by Eran Levin Jeff Acopian; Anne-Louise Band; Eugenio Clariond Reyes; Bettina Mathis; Sandy Read; Walter C. Sedgwick; Marc Weinberger. 11 Softening the Blow Advisory Trustees: Sharon R. Forsyth; Elizabeth Ames Jones; Travis Mathis; Wilhelmina Robertson; William New wind-energy research could help reduce bat kills Scanlan, Jr. Verne R. Read, Chairman Emeritus by Rebecca Patterson Scientific Advisory Board: Dr. Leslie S. Hall, Dr. Greg Richards, Bruce Thomson, Australia; Dr. Irina K. Rakhmatulina, Azerbaijan; Dr. NEWS & NOTES Luis F. Aguirre, Bolivia ; Dr. Wilson Uieda, Brazil; Dr. M. Brock Fenton, Canada ; Dr. Jiri Gaisler, Czech Republic; Dr. Uwe Schmidt, Germany; Dr. Ganapathy Marimuthu, Dr. Shahroukh Mistry, India; Dr. Arnulfo 14 Of bats and wine Moreno, Mexico; Ir. Herman Limpens, Netherlands; Dr. It’s time to apply for BCI Scholarships Armando Rodriguez-Duran, Puerto Rico; Dr. Ya-Fu Lee, Taiwan; Dr. Denny G. Constantine, Robert Currie, Dr. Do Bats Drink Blood? Theodore H. Fleming, Dr. Thomas H. Kunz, Dr. Gary F. McCracken, Dr. Don E. Wilson, United States; Dr. A plan for WNS José R. Ochoa G., Venezuela. Working together for bats and turkeys Membership Manager: Amy McCartney BATS (ISSN 1049-0043) is published quarterly by Bat BCI Member Snapshot Con ser vation International, Inc., a nonprofit corporation supported by tax-deductible contributions used for public The Wish List education, research and conservation of bats and the ecosys - tems that depend on them. © Bat Conser vation International, 2009. All rights reserved. Bat Conservation International’s mission is to conserve the world’s bats and their ecosystems in order to ensure a healthy planet. A subscription to BATS is included with BCI membership: Senior, Student or Educator $30; Basic $35; Friends of BCI $45; Supporting $60; Contributing $100; Patron $250; COVER PHOTO: The lesser mouse-tailed bat is a frequent user of abandoned Sustaining $500; Founder’s Circle $1,000. Third-class postage Israeli military bunkers that were modified to make them more friendly for paid at Austin, Texas. Send address changes to Bat Conser - roosting bats. (Story on Page 7.) vation International, P.O. Box 162603, Austin, TX 78716. © MERLIN D. TUTTLE, BCI / 8403101 Evolving Together ats play essential roles in healthy ecosystems – so much plants open their flowers at night or changed shape to Bso that various bat species have impacted the evolution attract bats and improve pollination. This evolutionary tit of insects they hunt or plants they pollinate. Bats evolved for tat has been going on for at least 50 million years. hunting aids, such as echolocation (emitting ultrasonic This issue of BATS features research that explores how an sounds and analyzing returning echoes to catch prey and evolving plant led one bat species to grow an enormously avoid obstacles in the dark), or grew longer snouts to reach long tongue and how katydids learned to escape attacking into flowers and lap nectar. Insects responded, for example, bats. Bats not only contribute greatly to nature, they helped by evolving hearing that is sensitive to ultrasound, while to shape it through many examples of coevolution. GOING TO GREAT LENGTHS Bats & flowers stage an evolutionary race by Nathan Muchhala a l a h h c u m N a h t a N f o y s e t r u o c fter hanging motionless for a spell, the bat suddenly stretches, cat-like, unfurling first one wing, then the other. It yawns widely and extends its tongue. And keeps extending it – longer and longer This bat extends its in a remarkable display. This is a tube-lipped nectar bat, and its tongue, at full stretch, reaches more remarkably long tongue 1 into a semiartificial flower Athan 1 ⁄2 times its body length. composed of a local plant The bat in my screened-in tent in Ecuador laps sugar-water from the bottom of a plastic test tube and a plastic test tube. The – and contributes to my efforts to determine why evolution produced such a spectacular tongue. test tube is attached to a I discovered this unique bat during fieldwork for my Ph.D. dissertation for the University of protractor-like device that Miami. In a paper coauthored with two Ecuadorian biologists, we named the species the tube-lipped measures the force that’s nectar bat ( Anoura fistulata ) because of its distinctive elongated lower lip. being applied by the bat. Volume 27, No. 3 FALL 2009 1 BATS Subsequent research demonstrated that this bat can extend is a repetitive loop: the flower grows longer to ensure pollina - its tongue some 3.3 inches (8.5 centimeters), twice as long as tion, while the moth’s tongue lengthens to reach more nectar, other nectar bats and longer, relative to body length, than any which causes the flower to grow longer, and so on. other mammal. Novel modifications of its mouth and throat The diet of tube-lipped nectar bats includes nectar from the allow it to store large portions of its retracted tongue in a flower Centropogon nigricans , which stores its nectar at the base 1 sleeve of tissue inside the rib cage. of 3- to 3 ⁄2-inch (8- to 9-centimeter) tubes. Could this plant and What evolutionary pressures could have brought about bat have coevolved in a race similar to that envisioned by such a spectacular tongue? In 2008, I returned to Ecuador Darwin? As with moths, the benefit of increased tongue lengths with financial support from Bat Conservation International to in nectar bats is clear: it allows the animal to reach more nectar. explore this question. The value of long tubes for the plant, however, is not as obvi - One possible answer was suggested by Charles Darwin. He ous. Unlike moths, Anoura fistulata and other nectar-eating bats hypothesized that the remarkably long tongue of a giant hawk drink nectar by extending and retracting the tongue, much as a moth in Madagascar evolved in a “race of increasing lengths” dog laps up water. This means that the bats will fully insert their with the exceptionally long nectar spur of the Malagasy star heads into even short-tubed flowers and extend their tongues orchid. Although the term “coevolution” wasn’t coined until only as far as needed to reach the nectar. So why would evolv - the 1960s, this was one of the first descriptions of a coevolu - ing a longer tube help the flower? tionary process. I suspected that although bats will fully insert their heads Darwin reasoned that, for moths, tongues equal to or into any flower, they push especially hard against flowers with longer than flower tubes would be required to reach all of the long tubes in an effort to reach that last drop of nectar. This nectar. From the flowers’ perspective, the tubes needed to be extra force should mean that they pick up and deposit more longer than moth tongues to ensure that the moth has to push pollen grains, which allows the plant to produce more seeds. its head into the flower, and thus pick up (or deposit) the To test this idea, I traveled into the cloud forests of pollen found there. A moth’s tongue (or proboscis) functions Ecuador’s Bellavista Reserve. With the help of three field assis - like a straw: nectar is sipped through a groove in the center. So tants, I set up nets around C. nigricans flowers and captured if a moth’s tongue is longer than the floral tube, it could con - four tube-lipped nectar bats. I held these bats for four days in sume all of the nectar while hovering outside of the flower and separate screened tents and performed two sets of experiments never actually touching the flower’s reproductive parts; the with them. flower goes unpollinated. The result of those opposing needs The first experiment involved flower proxies: plastic test courtesy of NathaN muchhala A tube-lipped nectar bat feeds on nectar from a flower of Aphelandra acanthus in Ecuador. BATS 2 FALL 2009 Volume 27, No. 3 photos courtesy of NathaN muchhala Nathan Muchhala peers through a microscope ( left ) to count pollen grains deposited in flowers by nectar-eating bats. The screen enclosures ( right ) housed the bats and the experiments, which demonstrated that longer flow - ers collected more pollen. tubes cut to six different lengths. I attached wire “stems” to the rather than those pushing directly into the flower.