0232 Herp Population Genetics/Herp Coloration, Symphony I & II
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0232 Herp Population Genetics/Herp Coloration, Symphony I & II, Monday 11 July 2011; ASIH STOYE GENERAL HERPETOLOGY AWARD Vincent Farallo Ohio University, Athens, OH, USA Predation and the Maintenance of Color Polymorphism in a Habitat Specialist Squamate In general, taxa exhibit color polymorphism when two or more morphs occur within a single population. However, there are instances where selection or limited gene flow can cause entire populations to become fixed for a single morph, resulting in separate populations of the same species exhibiting distinct color morphs. Morphs can be maintained through numerous mechanisms, one of which is natural selection via selective predation. The mottled rock rattlesnake is a montane species that exhibits striking levels of color polymorphism correlated with two distinct substrate types. Habitat substrate in the eastern part of their range is composed primarily of light colored limestone, whereas in the western region the substrate is primarily dark volcanic rocks. We hypothesized that predation on high contrast color and blotched patterns maintain these distinct color morphs. To test this we performed a predation experiment by deploying model snakes at 12 sites evenly distributed within the two regions where the different morphs are found. Two color and two blotched treatments were used to mimic the eastern and western morphs. We found that models contrasting with substrate coloration suffered significantly more avian attacks relative to models mimicking substrates. In regards to the two regions, neither of the blotched treatments was damaged by avian predators or non-predator disturbers more or less often. These results are consistent with the hypothesis that color pattern has, at least in part, been maintained by selective predation, and indicate that selective predation may also maintain blotching patterns but only when combined with differential behaviors. ______________________________________________________________________________ 0289 Poster Session II, Saturday 9 July 2011; STORER ICHTHYOLOGY AWARD Stacy Farina Cornell University, Ithaca, NY, USA The Evolution of Restricted or Siphon-Like Opercular Openings in Bony Fishes Restricted or siphon-like opercular openings occur in many groups of bony fishes. These undoubtedly represent many instances of convergent evolution, yet little has been done to characterize the phylogenetic distribution of such gill openings or to evaluate the different possible functions that they may reflect. For example, do the siphon-like opercular openings typical of some mormyrids function like those of lepidosirenid lungfishes? Do the restricted opercular openings in heavily armored pegasids function in the same way as those of boxfishes? To answer such questions, it is first important to examine the trait in an evolutionary context. To accomplish this, I defined a measurement that can be used to determine the extent of opercular opening restriction relative to the circumference of the head in the gill region. I analyzed eight additional body measurements to determine the diversity of body plans of fishes with restricted opercular openings. A broad survey of more than 300 families of bony fishes reveals more than 10 widely dispersed clades in which restricted opercular openings have independently evolved. Classification and Regression trees were used to analyze the morphometric data and categorize the diverse body plans represented within these clades. This survey will provide a basis for future comparison of the anatomy and function of the opercular apparatus across all fishes with restricted opercular openings. ______________________________________________________________________________ 0162 Herp Biogeography & Phylogeography, Minneapolis Ballroom E, Sunday 10 July 2011 Terence Farrell1, Brooke Deak1, Paul Andreadis2 1Stetson University, DeLand, FL, USA, 2Denison University, Granville, OH, USA Museum Specimen Records Indicate the Timber Rattlesnake is Expanding its Geographic Range in Florida Many North American viperids have suffered anthropogenic declines in geographic range and population density. We reviewed museum records for Crotalus horridus in Florida to document how the species fared during the 20th Century. Several lines of evidence indicate that this rattlesnake has significantly expanded its Florida range and abundance over the last 60 years. In the region from which C. horridus is recorded, the pattern of initial county discovery is highly contiguous: each county in which it was discovered was typically adjacent to a county in which it had previously been discovered. We ran computer simulations to generate null models for expected levels of contiguity, and the models typically yielded lower levels of contiguity. C. horridus also shows an aberrant sequence of initial county discovery compared to 22 species of abundant, widespread snake species from northern Florida. While the widespread species show a strongly concordant sequence of initial county discovery that reflects collecting effort, C. horridus does not. The spatial pattern of discovery within Alachua County, the most heavily collected region in Florida, shows evidence of a north-to-south expansion. The abundance of C. horridus relative to C. adamanteus is also increasing, though competitive causes are unlikely. Possible explanations for the expansion of C. horridus include fire suppression and declines in ophiophagous snake species. Museum collections hold great promise for documenting range changes. Care must be taken to develop appropriate null expectations and comparisons to widespread species are especially helpful in that effort. ______________________________________________________________________________ 0340 Poster Session II, Saturday 9 July 2011 Richard Feeney, Camm Swift Natural History Museum of Los Angeles County, Los Angeles, CA, USA Descriptions of Hybrid Sucker Larvae (Catostomus fumeiventris x santaanae) and Owens Sucker Larvae (C. fumeiventris) from Sespe Creek, Santa Clara River, Ventura County, California. Santa Ana suckers (C. santaanae) and Owens suckers (C. fumeiventris) are known to hybridize in the Fillmore area of the Santa Clara River system, including a tributary, Sespe Creek. Over 1940 sucker larvae and juveniles were collected in Sespe Creek in 2005. While they were predominately C. santaanae, some exhibited many intermediate characteristics between C. santaanae and C. fumeiventris including the amount of dorsolateral pigmentation, the extent and number of ventral gut melanophores, and the size of the larvae at various developmental stages. These hybrid larvae typically have less dorsolateral trunk pigment and a more continuous line of ventral gut melanophores; they are also larger at various stages than C. santaanae. Owens sucker (C. fumeiventris) larvae have even less dorsolateral pigment, a nearly continuous line of ventral gut melanophores and may be 5-10% larger than Santa Ana sucker larvae at key developmental stages. Continuous variation of the larval characters from C. santaanae to intermediate hybrids to C. fumeiventris types support the hypothesis of multiple backcrossing in adults. ______________________________________________________________________________ 0265 Fish Evolution, Minneapolis Ballroom F, Saturday 9 July 2011; ASIH STOYE GENERAL ICHTHYOLOGY AWARD Shobnom Ferdous Auburn University, Auburn, AL, USA Geometric Morphometrics as a Tool to Elucidate Phylogenies The use of morphometric data in phylogenetic analyses has long been debated. The disagreement primarily concerns whether or not morphometric data could be used to estimate phylogeny. With the development of geometric morphometrics, a better assessment of shape is available, reigniting debate over whether or not shape carries phylogenetic information and on how one can express that information. The phylogenetics of the genera of the North American minnows, dace, chubs, and shiners of the tribe Phoxinini have been well-studied with largely consistent results suggesting the phylogeny of the phoxinins is reasonably well-established. We developed a geometric morphometric database of representative phoxinins from each of the major clades in order to test methods of phylogenetic construction based on geometric morphometrics and whether there is phylogenetic signal in the data. We developed a set of 18 homologous landmarks for 29 genera, 44 species, and 362 specimens. The result shows that significant phylogenetic signal is present in the geometric morphometrics data set, but mostly at the tips of the tree. The overall pattern across phoxinins suggests reticulate evolution. The tree computed from landmark data of the phoxinins is not very consistent with the well-supported phylogenetic tree from molecular data. Although several studies have found congruence between shape and phylogeny, the phoxinins are likely more indicative of general patterns in organisms towards convergence in morphotypes. Thus, geometric morphometric data might not provide reliable information to infer phylogeny at larger scales. ______________________________________________________________________________ 0360 Poster Session III, Sunday 10 July 2011 Camila Rudge Ferrara, Richard C. Vogt, Renata S. Sousa-Lima INPA, Manaus, Brazil When do Hatchling Turtles Begin to Vocalize? Until recently aquatic turtles were thought to be deaf and mute. The function of the sounds produced by freshwater turtles have yet to be put into behavioral contexts. The present study was initiated to discover when young Podocnemis