Leafcutter ants cut trimmings from plants, carry them to their underground nests and cut them into smaller pieces before inoculating them with a fungus that serves as a primary food source for the colony. Cutting is energetically costly, so the amount of cutting is important in understanding foraging energetics. Estimates...
Background: Few studies examining the associations between long-term exposure to ambient air pollution and mortality have considered multiple pollutants when assessing changes in exposure due to residential mobility during follow-up.
Objective: We investigated associations between cause-specific mortality and ambient concentrations of fine particulate matter (≤ 2.5 μm; PM₂.₅), ozone (O₃),...
Humans, in conjunction with natural top-down processes and through a sequence of cascading trophic interactions, may have contributed
to the Pleistocene megafaunal extinctions. The arrival of the first humans, as hunters and scavengers, through top-down forcing, could have
triggered a population collapse of large herbivores and their predators. We present...
The temporal and spatial variability of crescentic sandbars is analyzed with hourly
long-term (months) video observations collected at four barred sites and are qualitatively
compared to the temporal and spatial variability predicted by hypotheses underpinning
existing approaches and models for crescentic bar formation (edge-wave template model,
linear stability analysis, and...
To provide sufficient food and fiber to the increasing global population, the technologies associated with crop protection are growing ever more sophisticated but, at the same time, societal expectations for the safe use of crop protection chemistry tools are also increasing. The goal of this perspective is to highlight the...
Recreational fishing has a long history in the USA, developing from the subsistence fisheries of Native Americans together with a partial subsistence fishery of later immigrants. Marine, diadromous, and aquatic taxa are targeted, including both vertebrates and macroinvertebrates. This paper defines recreational fishing, describes the main fishing techniques, identifies target...
We present the results of a study of optical scattering and backscattering of particulates for three coastal sites that represent a wide range of optical properties that are found in U.S. near-shore waters. The 6000 scattering and backscattering spectra collected for this study can be well approximated by a power-law...
K-Ar and ⁴⁰Ar-³⁹Ar geochronologic
data reveal the Paleocene to Eocene eruptive
history of volcanic centers which produced the
basaltic basement rocks of the Coast Range of
Oregon and Washington. Volcanism was short
lived at each center and migrated with time from
the northern and southern ends toward the
center, near...
Changes in the spatial distribution of U.S. west coast bottom-trawl effort in relation
to areas of prime habitat for rockfish Sebastes spp. were evaluated between 1992 and 2001. Prime trawlable rockfish habitat (PTRH) was defined based on the spatial distribution of high rockfish catches from logbook data for 1992–1995. Bottom-trawl...