Effectiveness of protected areas in north-eastern New South Wales: recent trends in six measures

We applied six measures of effectiveness to recent decisions about additional conservation areas in north-eastern New South Wales. Three have been widely used previously: (1) number of conservation areas; (2) total extent of conservation areas; and (3) representativeness (the proportion of natural features such as forest types or animal species represented in conservation areas to some targeted level). The other measures were: (4) efficiency or representation bias (the extent to which some features are protected above target levels at the expense of others that remain poorly protected); (5) relative protection of vulnerable areas within public land (percentage protection of flat, fertile areas relative to that of steep and/or infertile areas); and (6) relative protection of vulnerable areas across all tenures (the correlation between the amount of protection given to features and their vulnerabilities to clearing). We applied the measures in two chronological comparisons: the reserve system in 1994, 1996 and 1997; and before and after the Interim Assessment Process of 1996 which involved negotiations over new reserves and extensive unreserved areas that were temporarily deferred from logging. Over the study period, despite expansion of formal conservation and progress towards quantitative conservation targets, gazetted reserves remained strongly biased to the steep and/or infertile parts of public lands. Both gazetted reserves and areas deferred from logging increased the bias in protection away from forest types most vulnerable to clearing and for which regional conservation targets had already been most compromised. Two major challenges for future conservation decisions in the region are common to conservation planning generally: (1) to focus protection within public tenure on habitats and species most vulnerable to threatening processes such as logging; and (2) to provide more effective conservation management on private lands where loss of native vegetation continues.     

Spontaneous formation of macroscopic chiral domains in a fluid smectic phase of achiral molecules

A smectic liquid-crystal phase made from achiral molecules with bent cores was found to have fluid layers that exhibit two spontaneous symmetry-breaking instabilities: polar molecular orientational ordering about the layer normal and molecular tilt. These instabilities combine to form a chiral layer structure with a handedness that depends on the sign of the tilt. The bulk states are either antiferroelectric-racemic, with the layer polar direction and handedness alternating in sign from layer to layer, or antiferroelectric-chiral, which is of uniform layer handedness. Both states exhibit an electric field-induced transition from antiferroelectric to ferroelectric.     

A 50,000-year record of climate oscillations from Florida and its temporal correlation with the heinrich events

Oscillations of Pinus (pine) pollen in a 50,000-year sequence from Lake Tulane, Florida, indicate that there were major vegetation shifts during the last glacial cycle. Episodes of abundant Pinus populations indicate a climate that was more wet than intervening phases dominated by Quercus (oak) and Ambrosia-type (ragweed and marsh-elder). The Pinus episodes seem to be temporally correlated with the North Atlantic Heinrich events, which were massive, periodic advances of ice streams from the eastern margin of the Laurentide Ice Sheet. Possible links between the Tulane Pinus and Heinrich events include hemispheric cooling, the influences of Mississippi meltwater on sea-surface temperatures in the Gulf of Mexico, and the effects of North Atlantic thermohaline circulation on currents in the Gulf.     

Domesticated nature: shaping landscapes and ecosystems for human welfare

Like all species, humans have exercised their impulse to perpetuate and propagate themselves. In doing so, we have domesticated landscapes and ecosystems in ways that enhance our food supplies, reduce exposure to predators and natural dangers, and promote commerce. On average, the net benefits to humankind of domesticated nature have been positive. We have, of course, made mistakes, causing unforeseen changes in ecosystem attributes, while leaving few, if any, truly wild places on Earth. Going into the future, scientists can help humanity to domesticate nature more wisely by quantifying the tradeoffs among ecosystem services, such as how increasing the provision of one service may decrease ecosystem resilience and the provision of other services.     

Paleoindian seafaring, maritime technologies, and coastal foraging on California's Channel Islands

Three archaeological sites on California's Channel Islands show that Paleoindians relied heavily on marine resources. The Paleocoastal sites, dated between ~12,200 and 11,200 years ago, contain numerous stemmed projectile points and crescents associated with a variety of marine and aquatic faunal remains. At site CA-SRI-512 on Santa Rosa Island, Paleocoastal peoples used such tools to capture geese, cormorants, and other birds, along with marine mammals and finfish. At Cardwell Bluffs on San Miguel Island, Paleocoastal peoples collected local chert cobbles, worked them into bifaces and projectile points, and discarded thousands of marine shells. With bifacial technologies similar to those seen in Western Pluvial Lakes Tradition assemblages of western North America, the sites provide evidence for seafaring and island colonization by Paleoindians with a diversified maritime economy.     

Identity and search in social networks

Social networks have the surprising property of being "searchable": Ordinary people are capable of directing messages through their network of acquaintances to reach a specific but distant target person in only a few steps. We present a model that offers an explanation of social network searchability in terms of recognizable personal identities: sets of characteristics measured along a number of social dimensions. Our model defines a class of searchable networks and a method for searching them that may be applicable to many network search problems, including the location of data files in peer-to-peer networks, pages on the World Wide Web, and information in distributed databases.     

Climatic fluctuations due to deep ocean circulation

A simple climate model that includes the effect of deep ocean turnover as a pure time delay exhibits an oscillatory behavior. The deep ocean signal contains frequencies characteristic of both the forcing function and the deep ocean delay.     

Isolation of St. Louis encephalitis virus from overwintering Culex pipiens mosquitoes

Two strains of St. Louis encephalitis virus were isolated from overwintering mosquitoes collected in Maryland and Pennsylvania during January and February 1977. There isolations from Culex pipiens constitute evidence that a mosquito-borne flavivirus can persist in a vector mosquito in temperate climates during the winter season.