Genetic variation underlies plastic responses to global change drivers in the purple sea urchin, Strongylocentrotus purpuratus.

Phenotypic plasticity and adaptive evolution enable population persistence in response to global change. However, there are few experiments that test how these processes interact within and across generations, especially in marine species with broad distributions experiencing spatially and temporally variable temperature and pCO2. We employed a quantitative genetics experiment with the purple sea urchin, Strongylocentrotus purpuratus, to decompose family-level variation in transgenerational and developmental plastic responses to ecologically relevant temperature and pCO2. Adults were conditioned to controlled non-upwelling (high temperature, low pCO2) or upwelling (low temperature, high pCO2) conditions. Embryos were reared in either the same conditions as their parents or the crossed environment, and morphological aspects of larval body size were quantified. We find evidence of family-level phenotypic plasticity in response to different developmental environments. Among developmental environments, there was substantial additive genetic variance for one body size metric when larvae developed under upwelling conditions, although this differed based on parental environment. Furthermore, cross-environment correlations indicate significant variance for genotype-by-environment interactive effects. Therefore, genetic variation for plasticity is evident in early stages of S. purpuratus, emphasizing the importance of adaptive evolution and phenotypic plasticity in organismal responses to global change.

Hyperbaric programs in the United States: Locations and capabilities of treating decompression sickness, arterial gas embolisms, and acute carbon monoxide poisoning: survey results.

Hyperbaric oxygen therapy is the primary treatment for arterial gas embolism, decompression sickness and acute carbon monoxide poisoning. Though there has been a proliferation of hyperbaric centers throughout the United States, a scarcity of centers equipped to treat emergency indications makes transport of patients necessary. To locate and characterize hyperbaric chambers capable of treating emergency cases, a survey of centers throughout the entire United States was conducted. Using Google, Yahoo, HyperbaricLink and the UHMS directory, a database for United States chambers was created. Four researchers called clinicians from the database to administer the survey. All centers were contacted for response until four calls went unreturned or a center declined to be included. The survey assessed chamber readiness to respond to high-acuity patients, including staff availability, use of medical equipment such as ventilators and intravenous infusion devices, and responding yes to treating hyperbaric emergencies within a 12-month period. Only 43 (11.9%, N = 361) centers had equipment, intravenous infusion pumps and ventilators, and staff necessary to treat high-acuity patients. Considering that a primary purpose of hyperbaric oxygen therapy is the treatment of arterial gas embolism and decompression sickness, more hyperbaric centers nationwide should be able to accommodate these emergency cases quickly and safely.