Premium
WHY DOES THE YELLOW‐EYED ENSATINA HAVE YELLOW EYES? BATESIAN MIMICRY OF PACIFIC NEWTS (GENUS TARICHA ) BY THE SALAMANDER ENSATINA ESCHSCHOLTZII XANTHOPTICA
Author(s) -
Kuchta Shawn R.,
Krakauer Alan H.,
Sinervo Barry
Publication year - 2008
Publication title -
evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.84
H-Index - 199
eISSN - 1558-5646
pISSN - 0014-3820
DOI - 10.1111/j.1558-5646.2008.00338.x
Subject(s) - batesian mimicry , biology , aposematism , mimicry , zoology , salamander , subspecies , salamandridae , müllerian mimicry , genus , ecology , predator , caudata , predation
Color patterns commonly vary geographically within species, but it is rare that such variation corresponds with divergent antipredator strategies. The polymorphic salamander Ensatina eschscholtzii , however, may represent such a case. In this species, most subspecies are cryptically colored, whereas E. e. xanthoptica , the Yellow eyed ensatina, is hypothesized to be an aposematic mimic of highly toxic Pacific newts (genus Taricha ). To test the mimicry hypothesis, we conducted feeding trials using Western Scrub‐Jays, Aphelocoma californica. In every feeding trial, we found that jays, following presentation with the presumed model ( T. torosa ), were more hesitant to contact the presumed mimic ( E. e. xanthoptica) than a control subspecies lacking the postulated aposematic colors ( E. e. oregonensis ). The median time to contact was 315 sec for the mimic and 52 sec for the control. These results support the mimicry hypothesis, and we suggest that E. e. xanthoptica is likely a Batesian mimic, rather a Müllerian or quasi‐Batesian mimic, of Pacific newts.