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Jennifer Horney Matt Simon Shannon Grabich Philip Berke 《Journal of Environmental Planning and Management》2015,58(5):802-818
In accordance with the Disaster Mitigation Act, most US counties have a hazard mitigation plan (HMP) to reduce future disaster losses. HMPs are important as they can be used to proactively assess risk, direct future development, raise awareness and build consensus. Using a population-based sample, we interviewed residents of Bertie County, NC, about their awareness of and participation in the HMP process to determine if demographics, social vulnerability or hazard vulnerability were associated with increased awareness or participation. We also assessed whether these factors were associated with knowledge of policy changes and investments that were adopted in the HMP. Overall, the unemployed were the only group less likely to report awareness of or participation in HMP development. African-Americans, mobile home residents, the poor, short-term residents and those with less disaster experience were less likely to be aware of policies and investments prioritised in the HMP. Targeted efforts to increase awareness could potentially improve disaster outcomes among vulnerable populations. 相似文献
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Jennifer C. Cornell Nancy E. Stamp M. Deane Bowers 《Behavioral ecology and sociobiology》1987,20(6):383-388
Summary Changes in response to attack and the tendency to aggregate were examined in the six larval instars of the buckmoth, Hemileuca lucina (Saturniidae). In response to simulation of attack by a parasitoid and of biting by a predator, early instars (I, II, and III) exhibited defensive behavior much more often than escape behaviors, whereas late instar larvae (IV, V, and VI) usually resorted to escape rather than defend themselves. The situations in which attacked larvae were most likely to stimulate other group members to respond were: second and third instar larvae thrashing in response to simulation of a parasitoid or headrearing in response to simulation of a biting predator; and fourth, fifth and sixth instar larvae dropping in response to either stimulus. An index of reaggregation indicated that first instar larvae had difficulty reaggregating; second, third and fourth instar larvae reaggregated quickly; and fifth and sixth larvae dispersed. As larvae developed, the change from predominantly defense to escape behaviors paralleled the decline in tendency to aggregate. 相似文献
116.
Graded recruitment in a ponerine ant 总被引:6,自引:0,他引:6
Michael D. Breed Jennifer H. Fewell Allen J. Moore Kristina R. Williams 《Behavioral ecology and sociobiology》1987,20(6):407-411
Summary (1) The giant tropical ant, Paraponera clavata, exhibits graded recruitment responses, depending on the type, quantity, and quality of a food source. More ants are initially recruited to a large prey or scavenge item than to a large quantity of sugar water. (2) Individual ants encountering prey items gauge the size and/or unwieldiness of the item, regardless of the weight, when determining whether to recruit. (3) The trail pheromone of this species is often used as an orientation device by individual ants, independent of recruitment of nestmates. (4) It is proposed that the foraging behavior of P. clavata represents one of the evolutionary transitions from the independent foraging activities of the primitive ants to the highly coordinated cooperative foraging activities of many higher ants. 相似文献
117.
A study was made of the pigment composition and ultrastructure of a unicellular cyanophyte living in symbiosis with colonial didemnid ascidians and encrusting sponges collected from the southern end of the Great Barrier Reef, Australia, in 1981–1984. The ascidians were Trididemnum tegulum Kott and T. clinides. Kott; the sponges were Prianos aff. melanos de Laubenfels, Spirastrella aff. decumbens Ridley and an unidentified brown fleshy sponge (BFS). This cyanophyte seems to be identical with Synechocystis trididemni Lafargue et Duclaux. A phycoerythrin containing both phycourobilin and phycoerythrobilin chromophores was shown to be present; the urobilin was carried on and subunits, no subunit was found. A second phycoerythrin possessing only erythrobilin chromophores was also present. In thin-sections the cells showed no central DNA-containing nucleoid, and an unusual thylakoid arrangement with some thylakoids having greatly expanded lumens forming pseudo-vacuoles in the centre of the cell. Freeze-fracture showed 11 to 12 nm particles on both PF (protoplasmic face) and EF (exoplasmic face) faces of thylakoids. In many ways, the ultrastructure resembled that of the chlorophyll-b containing prokaryote Prochloron spp. 相似文献
118.
Raphaël Jeanson Jennifer H. Fewell Root Gorelick Susan M. Bertram 《Behavioral ecology and sociobiology》2007,62(2):289-298
Empirical evidence suggests that division of labor in insect societies is positively related to group size both within and
across taxa. Response threshold models (RTM) have been commonly used to analyze patterns of division of labor. However, these
models have been explored empirically and theoretically for only a limited number of tasks, and few studies have examined
predictions of the model as colony size and work availability change. We theoretically examine how group size influences division
of labor using a fixed response-threshold model. We simultaneously explore how expected by-products of increased colony size,
including demand (total work need relative to total work force available) and task number, affect this relationship. Our results
indicate that both low demand and high task number positively influence division of labor. We suggest that these changes parallel
what is observed within social groups as their size increases, and that, in part, the commonly observed increased division
of labor with increasing group size is emergent. 相似文献
119.
A geo-referenced data set of 12 228 first-time blood lead screening values for Syracuse, NY, children was established for the 4-year period 1992–1996. Soil lead values were measured in a 600 m by 600 m tessellation grid covering the city. The two data sets were merged for evaluation of relationships between them. Strong seasonal variation in blood lead levels suggests the importance of contaminated soils as an exposure source. When the data were aggregated at a large geographic scale (3 km2), a logarithmic model showed an R2 of > 0.65 for the regression of geometric mean blood lead on median soil lead values. Results showed a striking similarity to those obtained by Mielke et al. (1999) for a study in New Orleans, LA, USA. 相似文献
120.
Jennifer E. Smith Sandra K. Memenis Kay E. Holekamp 《Behavioral ecology and sociobiology》2007,61(5):753-765
When social partners vary in their relative value, individuals should theoretically initiate partnerships with conspecifics
of the highest value. Here, we tested this prediction in a wild population of spotted hyenas (Crocuta crocuta). Crocuta live in complex, fission–fusion societies structured by dominance hierarchies in which individuals vary greatly in their
value as social companions. Because patterns of association among Crocuta reflect social preferences, we calculated association indices (AIs) to examine how social rank influences intrasexual partner
choice among unrelated adults of both sexes. The highest-ranking individuals were generally most gregarious in both sexes.
Females associated most often with dominant and adjacent-ranking females. Females joined subgroups based on the presence of
particular conspecifics such that subordinates joined focal females at higher rates than did dominants. Dominants benefit
from associations with subordinates by enjoying priority of access to resources obtained and defended by multiple group members,
but the benefits of these associations to subordinates are unknown. To investigate this, we tested three hypotheses suggesting
how subordinates might benefit from rank-related partner choice among unrelated females. We found that subordinates who initiated
group formation benefited by gaining social and feeding tolerance from dominants. However, rates at which dominants provided
coalitionary support to subordinates did not vary with AIs. Overall, our data resemble those documenting patterns of association
among cercopithecine primates. We consider our results in light of optimal reproductive skew theory, Seyfarth’s rank attractiveness
model, and biological market theory. Our data are more consistent with the predictions of Seyfarth’s model and of biological
market theory than with those of skew theory. 相似文献