Allocation of Reproductive Effort to the Male and Female Strategies in Wind-Pollinated Plants

Amaranthus and several other wind-pollinated species of plants are used to test some of the theoretical models of relative reproductive effort towards the male and female sexes. Consistent with these models, in self-compatible, monoecious Amaranthus, Chenopodium, Digitaria, Setaria, and Lepidium, female effort represented over 90% of the total reproductive effort. Also consistent with predictions, Lolium, a self-incompatible wind-pollinated species, was found to have about equal male and female effort. A method is described here that should prove useful in quantifying male and female effort in both wind and insect-pollinated species of plants

RELATIONSHIP BETWEEN RELATIVE BRAIN SIZE AND CLIMBING ABILITY IN \u3ci\u3ePEROMYSCUS\u3c/i\u3e

Eisenberg and Wilson (Evolution, 32:740-751, 1978) have documented an interesting relationship between the relative brain size of bats and the complexity of the habitat in which they forage. They found that bats that fly and forage through foliage have larger brains relative to their body size than those that forage in open air. Their explanation was that bats in the complex habitat must process more complex sonic information to navigate through the foliage. In order to do this a larger brain is required. The Peromyscus of North America may offer a similar paradigm as far as habitat complexity is concerned. Species of this genus can be found associated with a variety of habitats: forest, brushlands, rock slides, and grasslands. It seems reasonable that these structurally different habitats may require different climbing abilities by the Peromyscus inhabitants. If functioning in a structurally complex habitat requires a relatively larger brain to process information than is required in a structurally simple habitat, then, following the logic of Eisenberg and Wilson (1978), those species that are good climbers will have relatively larger brains than species that are poor climbers. If this hypothesis is correct, such a pattern of morphological variation in brain size may be expected intraspecifically in P. maniculatus and P. leucopus, two species that occur in a wide varietv of habitats throughout their range

Maximum Entropy Modeling of Indiana Bat (Myotis Sodalis) Maternity Roost Habitat

Since 1967, the Indiana bat (Myotis sodalis) has been on the U.S. Endangered Species list due to disruption of hibernating bats in caves, summer habitat degradation, and more recently, the onset of White-nose Syndrome. The purpose of this study is to evaluate landscape variables associated with Indiana bat maternity roost trees in an attempt to better understand what factors play a role in their distribution in north central Missouri. I tracked reproductive female Indiana bats to 20 different primary and secondary roost trees; these are roosts that had multiple bats visit them on multiple occasions. GPS location data for these roosts and 6 environmental parameters (aspect, distance to forest edge, distance to stream or river, elevation, percent tree canopy, and slope) were used as input variables for a MaxEnt model of species distribution. I used ENMTools to identify which analysis features produced the best MaxEnt model for this data set. Linear and quadratic analysis features, separately, fit the data the best. When cross-validated through four replicates, the two models performed equally well with area under the curve (AUC) values of 0.792 and 0.764. Distance to forest edge was the variable with the most influence in both models, followed by elevation and distance to stream. Macro-scale environmental variables provide insight to modeling areas in which Indiana bat maternity roosts might be found in the future. This provides researchers and wildlife managers with a toolset to identify potential habitat to aid in species recovery

Graduate Research Experiences in School Psychology and Future Commitment to Conducting Research in Schools

The execution of a research project is required by graduate training programs in school psychology. Yet little is nkown about the long-term consequences of completing a major research project on practitioner\u27s attitudes towards research in the schools

Microhabitat Selection in Two Species of Heteromyid Rodents

An experiment was conducted to determine the microhabitat preferences of two heteromyid rodents, Dipodomys ordi and Perognathus flavus. This experiment used marked seeds and the atomic absorption spectrophotometer in order to study the environment as a mosaic of microhabitats. The results of our analysis indicate that these two heteromyids are microhabitat selectors. The preferences of the rodents are, D. ordi: grass habitat 0.0%, near grass habitat 22.5%, open habitat 77.4%, and P. flavus: grass habitat 46.2%, near grass habitat 32.2%, open habitat 21.4%. The overlap between the two species is only 0.43

Simple predictors of bite force in bats: The good, the better, and the better still

Bite forces of 39 species from six families of New World bats with a variety of diets are quantified with a force meter under field conditions. Using regression approaches we search for a model that is a good morphological predictor of these bite forces. Body mass, an index that ignores differences in skull morphology, has a statistically significant relationship with bite force (R2 = 0.76) but is a relatively poor predictor compared with our best model (R2 = 0.94). The two best models of the eight we examine are one based on an estimate of strength of dentary, which is really simple beam theory; and the other based on muscle mass and jaw mechanics of input and output arms. Both models explain about 90% of the variation in bite force. However, the combination of these variables together in multiple regression works even better, explaining about 94% of the variation. Our model derived from beam theory relies on bony characteristics, which are readily available from museum specimens. This model will be of particular use to students of fossils or ecomorphology for inferring bite force. We also test Freeman’s earlier predictions about bite forces of bats with gracile versus robust skulls. These predictions can be only partially confirmed. For species we measured, bats with gracile skulls did have weak bites; however, bats designated by Freeman as having robust skulls did not have particularly strong bites

Current status of the Northern Long-eared Myotis (\u3ci\u3eMyotis septentrionalis\u3c/i\u3e) in northwestern Nebraska

The Northern Long-eared Myotis (Myotis septentrionalis; Order: Chiroptera) occurs in eastern, southern, and northern Nebraska, but its current distribution in northwestern parts of the state is unclear due to its recent arrival to the region. We investigated the status of this species in the Pine Ridge via mist net (2011-2014) and acoustic surveys (2014). We documented nine species of bats in the region, including M. septentrionalis. Of 423 total bats, M. septentrionalis was represented by four individuals, the fewest of all species during our four-year survey. We only documented M. septentrionalis in Sheridan County; this county is where the species was first reported in the Pine Ridge. Possibly acoustic calls of M. septentrionalis were recorded along the White River in Dawes County, but they likely represented variant calls from other Myotis species, such as the Little Brown Myotis (Myotis lucifugus). Until more conclusive evidence is obtained from Dawes County, we do not consider M. septentrionalis as part of the bat fauna from the county. Captures of three lactating M. septentrionalis are the best evidence of a reproducing population in the Pine Ridge. We conclude that the Northern Long-eared Myotis currently is not widely distributed in northwestern Nebraska, especially during summer when females bear and raise young. During migratory periods, however, limited evidence suggests individuals occur across a broader area using more habitats while in route to and from hibernacula. Periodic surveys are warranted to monitor the status of this species in the region. Additional research to determine summer and winter roosts would promote and help to conserve habitats for this species in Nebraska as M. septentrionalis recently was listed as federally threatened in the United States