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451.
We used sequence variation within 297 bp of control region mitochondrial DNA (mtDNA) amplified from 53 lesser long-nosed bats, Leptonycteris curasoae (Phyllostomidae: Glossophaginae) captured at 13 locations in south-western United States and Mexico and one site in Venezuela to infer population structure and possible migration routes of this endangered nectar- and fruit-eating species. Phylogenetic analysis using maximum parsimony and UPGMA confirmed species and subspecies distinctions within Leptonycteris and revealed two clades exhibiting 3% sequence divergence within the Mexican subspecies, L. c. yerbabuenae . Even though many roosts contained L. c. yerbabuenae from both clades, weak population structure was detected both by a correlation between genetic differentiation, F st , and geographical distance and by a cladistic estimate of the number of migration events required to align bat sequences with geographical location on maximum parsimony, as compared to random, trees. Three results suggest that L. c. yerbabuenae are more likely to migrate between sites along the Pacific coast of Mexico or along the foothills of the Sierra Madre Occidental than between these regions. (1) Seventeen of 20 bats which shared an identical sequence were captured up to 1800 km apart but within the same putative migration corridor. (2) Residuals from a regression of F st on distance were greater between than within these regions. (3) Fewer migration events were required to align bats with these two groups than expected from random assignment. We recommend analysing independent genetic data and monitoring bat visitation to roost sites during migration to confirm these postulated movements. 相似文献
452.
Eavesdropping on the echolocation and social calls of bats 总被引:3,自引:0,他引:3
M. B. FENTON 《Mammal Review》2003,33(3-4):193-204
453.
CHAD P. LEHMAN DANIEL J. THOMPSON MARK A. RUMBLE 《The Journal of wildlife management》2010,74(2):295-299
ABSTRACT Concealment cover is important for ground-roosting wild turkey (Meleagris gallopavo) poults immediately following hatch during the vulnerable, preflight stage. We compared concealment cover resources selected at ground roosts to those of nest sites and available resources for Merriam's turkeys (Meleagris gallopavo merriami) in the Black Hills of South Dakota, USA. Females with preflight poults selected ground roosts that were similar in structure to nest sites. Ground roosts and nests were greater in visual obstruction (unit odds ratios ≥1.19) than random sites. However, ground roosts were closer to meadow-forest edges than either nests or random sites (unit odds ratios ≤0.98). Structure at ground roosts may provide visual protection from predators, and management for shrub vegetation or woody debris along meadow-pine forest ecotones will provide cover for Merriam's turkey broods. 相似文献
454.
455.
Recent behavioral observations have indicated that bats can sense the Earth's magnetic field. To unravel the magnetoreception mechanism, the present study has utilized magnetic measurements on three migratory species (Miniopterus fuliginosus, Chaerephon plicata, and Nyctalus plancyi) and three non‐migratory species (Hipposideros armiger, Myotis ricketti, and Rhinolophus ferrumequinum). Room temperature isothermal remanent magnetization acquisition and alternating‐field demagnetization showed that the bats' heads contain soft magnetic particles. Statistical analyses indicated that the saturation isothermal remanent magnetization of brains (SIRM1T_brain) of migratory species is higher than those of non‐migratory species. Furthermore, the SIRM1T_brain of migratory bats is greater than their SIRM1T_skull. Low‐temperature magnetic measurements suggested that the magnetic particles are likely magnetite (Fe3O4). This new evidence supports the assumption that some bats use magnetite particles for sensing and orientation in the Earth's magnetic field. Bioelectromagnetics 31:499–503, 2010. © 2010 Wiley‐Liss, Inc. 相似文献