Acclimatization of the tropical reef coral Acropora millepora to hyperthermal stress

The demise of reef-building corals potentially lies on the horizon, given ongoing climate change amid other anthropogenic environmental stressors. If corals cannot acclimatize or adapt to changing conditions, dramatic declines in the extent and health of the living reefs are expected within the next half century. The primary and proximal global threat to corals is climate change. Reef-building corals are dependent upon a nutritional symbiosis with photosynthetic dinoflagellates belonging to the group Symbiodinium. . The symbiosis between the cnidarian host and algal partner is a stress-sensitive relationship; temperatures just 1°C above normal thermal maxima can result in the breakdown of the symbiosis, resulting in coral bleaching (the loss of Symbiodinium and/or associated photopigments) and ultimately, colony death. As ocean temperatures continue to rise, corals will either acclimatize or adapt to changing conditions, or will perish. By experimentally preconditioning the coral Acropora millepora via sublethal heat treatment, the coral acquired thermal tolerance, resisting bleaching during subsequent hyperthermal stress. The complex nature of the coral holobiont translates to multiple possible explanations for acclimatization: acquired thermal tolerance could potentially originate from the host itself, the Symbiodinium, or from the bacterial community associated with the coral. By examining the type of in hospite Symbiodinium and the bacterial community prior acclimation and after thermal challenge, it is shown that short-term acclimatization is not due to a distinct change in the dinoflagellate or prokaryote community. Though the microbial partnerships remain without considerable flux in preconditioned corals, the host transcriptome is dynamic. One dominant pattern was the apparent tuning of gene expression observed between preconditioned and non-preconditioned treatments, showing a modulated transcriptomic response to stress. Additionally several genes were upregulated in association with thermal tolerance, including antiapoptotic genes, lectins, and oxidative stress response genes. Upstream of two of these thermal tolerance genes, inhibitor of NFκB and mannose-binding lectin, DNA polymorphisms were identified which vary significantly between the northern and southern Great Barrier Reef. The impact of these mutations in putative promoter regions remains to be seen, but variation across thermally-disparate geography serves to generate hypotheses regarding the role of regulatory element evolution in a coral adaptation context.

The Role of the FIU Nature Preserve in Promoting Physical Activity

The FIU Nature Preserve was established over thirty-five years ago as an environmental educational center where visitors could experience and learn about local south Florida ecosystems and organisms. This 16-acre facility in the heart of the MMC campus has recently become a popular outdoor fitness destination since the inauguration of a jogging path during Fall 2013. This study set out to quantify how many people visit the FIU Nature Preserve annually, who they are, and what they are doing there. It is also assessing the effect of the FIU Nature Preserve on the overall health of the university community since studies have found that physical activity and contact with nature are positively associated with good health. A pilot was completed during Fall 2014, and the study is on track to finish March 22, 2015. To measure current visitation, two types of surveys were done on seven days across seven weeks during the spring of 2015, visitation counts and in-person surveys. By understanding the reasons and ways people discover and embark on regular use of natural areas, land managers and policy makers can make more informed decisions. As human population and development continue to grow, new ways to integrate natural areas into our urban environment and our lifestyles must be found. In this way, natural resource conservation could be championed as a way for communities to promote physical activity and good health beyond simply using their intrinsic value.