BAT TALK DO BA T S U S E LA N G U a G E ? Volume 2 2, No
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Bats Along C h e m i s t r y and TH E AM A Z O N MI G R A T I O N MYST E R I E S W W W . B A T C O N . O R G F A L L 2 0 0 4 BAB A T C O N S E R VAT I O NT I N T E R N AST I O N A L BAT TALK DO BA T S U S E LA N G U A G E ? Volume 2 2, No. 3, FALL 2 004 BATS P.O. Box 162603, Austin, Texas 78716 (512) 327-9721 • Fax (512) 327-9724 Publications Staff D i rector of Publications: Robert Locke Photo Editor: Kristin Hay Copyeditors: Angela England, Valerie Locke B AT S welcomes queries from writers. Send your article proposal with a brief outline and a description of any photos to the address above or via e-mail to: [email protected]. FEATURES M e m b e r s : Please send changes of address and all correspondence to the address above or via e-mail to [email protected]. Please include your label, if possible, and allow six weeks for the change 1 Bat Talk of address. Do bats possess language? Founder & Pre s i d e n t : Dr. Merlin D. Tuttle by Ro b e rt Locke Associate Executive Director: Elaine Acker B o a rd of Tru s t e e s : John D. Mitchell, Chair 7 Bats Along the Amazon Mark Adkins, Vice Chair BCI members explore the wonders of Brazil Verne R. Read, Chairman Emeritus Peggy Phillips, Secretary by Bobbi Chaney Elizabeth Ames Jones, Treasurer Jeff Acopian; Eugene L. Ames, Jr.; Charles C. Chester; Robert 12 Chemistry and Migration Mysteries E. Gerrie; Nancy Harte; Joan Kelleher; Travis Mathis; Scott M c Vay; Thomas Read; Eugenio Clariond Reyes; Wilhelmina Fur holds clues to previous journeys E. Robertson; William Scanlan; Lee Schmitt; Patsy Steves; Dr. by Paul Cry a n Merlin D. Tuttle; Roy Vaughan; Marc We i n b e r g e r. Advisory Trustees: Sharon R. Forsyth; Dr. D.J. Sibley, Jr. DEPARTMENTS Scientific Advisory Board : Dr. Leslie S. Hall, Dr. Greg Richards, Bruce Thomson, Australia; Dr. Irina K. Rakhmatulina, Azerbaijan; Dr. Luis F. 14 News and Notes Aguirre, Bolivia; Dr. Wilson Uieda, Brazil; Dr. M. Brock Fenton, Canada; Dr. Jiri Gaisler, Czech Republic; Dr. Uwe Bats without borders Schmidt, G e r m a n y ; D r. Ganapathy Marimuthu, Dr. You can make a difference! Shahroukh Mistry, India; Dr. Rodrigo Medellín, Dr. Arnulfo Moreno, Mexico; Ir. Herman Limpens, Netherlands; Dr. Bats on Parade in Missouri Armando Rodriguez-Duran, Puerto Rico; Dr. Ya-Fu Lee, BCI Workshops 2005 Taiwan; Dr. Paul A. Racey, United Kingdom; Dr. Denny G. ‘Greetings from Iraq’ Constantine, Robert Currie, Dr. Theodore H. Fleming, Dr. Thomas H. K u n z , Dr. Gary F. McCracken, Dr. Don E. Wilson, The Wish List United States; Dr. José R. Ochoa G., Venezuela. Membership Manager: Amy McCartney B AT S (ISSN 1049-0043) is published quarterly by Bat Conservation International, Inc., a nonprofit corporation supported by tax-deductible contributions used for public education, research and conservation of threatened and endangered bats. © Bat Conservation International, 2004. All rights reserved. Bat Conservation International is dedicated to conserving and restoring bat populations and habitats around the world. Using COVER PHOTO: Mexican free-tailed bats (Tadarida brasiliensis) communicate with one non-confrontational approaches, we educate people about the ecological and economic values of bats, advance scientific another through a complex series of calls that are now being translated. The graphic shows knowledge about bats and the ecosystems that rely on them and how a courtship call looks on an oscilloscope. New research suggests many of those calls preserve critical bat habitats through win-win solutions that benefit both humans and bats. consist of “phrases” which can be combined in different ways to produce different meanings. A subscription to BATS is included with BCI membership: That begins to resemble a language of sorts. Please see page 1. Senior, Student or Educator $30; Basic $35; Friends of BCI $45; Supporting $60; Contributing $100; Patron $250; Sustaining © MERLIN D . TUTTLE, BC I / 8436210 $500; Founder’s Circle $1,000. Third-class postage paid at Austin, Texas. Send address changes to Bat Conservation International, P.O. Box 162603, Austin, TX 78716. BATS is printed on a 50/20 chlorine-free recycled paper with a PHOTO BY PHIL VOLKER (SEE PAGE 7) water-based coating on the cover. by Robert Locke BatBat TalkTalk The male free-tailed bat at left delivers Do bats his warning territorial call squarely into the face of a potential intruder. The spectrogram below shows the structure of the territorial call. possess language? exican free-tailed bats, that at least some of those calls are researchers find, have a composed of specific “phrases” – rich repertoire of distinct sounds that can be mixed and matched and complex calls that to convey very different meanings. If Mplay a major role in social interactions. confirmed by subsequent studies, that Now scientists are finding something would come stunningly close to what much more surprising: strong hints we call language. When “conversation” fails, a tussle can result, as when this male, whose courtship call produced results, defends his home pouch and harem from another – less successful – male. (These photos were taken from the research videos of Barbara French’s rescued bats.) Volume 22, No. 3 F A L L 2 0 0 4 1 B A T S “What is becoming apparent here is that the way bats use [their communica- tion signals] is ve ry sophisticated and may have rules to guide it,” said neuro- physiologist George Pollak of the Un i versity of Texas at Au s t i n . “Those rules may invo l ve syntax and g r a m m a r. If you combine those signals in c e rtain ways, the meaning changes ac- c o rding to how they are combined. T h a t s t a rts to approach language, albeit in a ve ry primitive, ru d i m e n t a ry way. ” “ Now,” Pollak said, “we have to prove it. I’m not positive yet, but I’m assem- bling a whole group of people to try to p rove this.” The next step: trying to talk to the b a t s . First hints The new re s e a rch has been pre s e n t e d at several international scientific meet- ings, and “people are just floored by this,” said Pollak, who has studied how bats handle auditory signals for some 30 ye a r s . BCI Science Officer Barbara French feeds a Mexican free-tailed bat in her Bat Barn, where she rehabil- “I was just amazed when we first re c o rd- itates disabled bats and keeps a colony of up to 75 bats that cannot be returned to the wild. The ed these signals at Ba r b a r a’s [Bat Ba r n ] . ” blue pouches on the walls are roosting quarters for the bats. Barbara French handles countless within their social contexts, they eve n t u- that bats use to locate, greet, argue and information queries as BCI’s Science ally found that many specific calls we re play with one another and to express irri- Of f i c e r, but after hours, she rescues and associated with ve ry specific behaviors – tation, anticipation and affection. Ove r rehabilitates bats at her home and has both by the calling bat and by others in the years, they have “t r a n s l a t e d” about maintained a colony of rescued Me x i c a n the vicinity. two dozen vocalizations, linking each f ree-tailed bats (Tadarida bra s i l i e n s i s) at The two veteran rehabilitators had an one to a specific behavior (“What Ba t s the Bat Barn for a decade. Sh e’s been i m p o rtant advantage in their re s e a rc h : Talk About,” page 4). Bats at both cap- studying the social communication of Each maintains a captive colony of 50 to t i ve colonies use similar calls. f ree-tailed bats since about 1995, work i n g 75 rescued bats that, for various re a s o n s , for much of that time with fellow re h a- cannot be released into the wild. After The noisy Bat Barn bilitator Amanda Lollar of Bat Wo r l d often-extended medical care and hand A colony of Mexican free tails seems Sa n c t u a r y in Mineral Wells, Texas (BAT S feeding, they get to know their bats, like a noisy place filled with raging hor- Summer 2000). learning to identify each one and to re c- mones, nervous conversation and boys Echolocation calls that bats make o g n i ze personality differe n c e s . and girls trying to figure out where while hunting have been well document- And, of course, they hear bats chatter- everybody fits into this little society. ed, but previous behavior-related vo c a l- ing continually. In wild colonies, individ- Consider this extended conversation ization studies have seldom inve s t i g a t e d ual calls are buried under the wild from French’s free tails: individual interactions.