How does rising atmospheric CO2 affect marine organisms?

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Marine Invertebrate Larvae in a CO2-Enriched and Warmer World
Volume 17, Number 13: 26 March 2014

Concerned that the predicted "stunting effect" of CO2-induced ocean acidification on the future development of calcifying invertebrate larvae has emerged as a supposedly "significant effect of global change," Byrne et al. (2014) assessed the arm growth response of sea urchin echinoplutei, which they used as a proxy for larval calcification, via a "global synthesis" of pertinent data they obtained from the scientific literature on the subject.

This work revealed, in their words, that "regardless of habitat or latitude, ocean acidification impedes larval growth." However, they also found that "when temperature is added to the stressor mix, near-future warming can reduce the negative effect of acidification on larval growth," since "increased temperature has the opposite effect, resulting in faster growth, larger larvae and skeletons and enhanced metabolism in warmer conditions." And they write that "thus far, the interactive effects of near-future ocean warming and acidification on marine invertebrate development have been investigated for 23 species (three corals, nine molluscs, six echinoderms and five crustaceans) including three sea urchin species," adding that "in several studies, near-future warming, not acidification, is the more important stressor, especially with regard to survivorship of early embryos (Nguyen et al., 2012; Amberg et al., 2014)."

The five scientists also note that "the ocean will change over coming decades more gradually than in laboratory experiments." And, therefore, they suggest that changing ocean conditions may result in the production of more resistant invertebrate larvae, through phenotypic buffering and natural selection. In addition, they write that "acclimatization of urchins and oysters to moderately elevated pCO2 can result in trans-life cycle enhancement of larval and juvenile tolerance of reduced pH in some species," citing the studies of Parker et al. (2012) and Dupont et al. (2014). And they similarly note that "trans-generational phenotypic resilience to increased temperature has also been shown for sea urchins," citing O'Connor and Mulley (1977) and Johnson and Babcock (1994).

In concluding, Byrne et al. write that "adaptation through natural selection over coming decades may also facilitate persistence in a changing ocean, especially for species from warmer latitudes that have a comparatively shorter generation time compared with polar species." In addition, they note that "recent quantitative genetics and genomic studies with echinoids indicate the presence of traits to facilitate resilience and adaptation (genetic) to ocean acidification (Pespini et al., 2012; Kelly et al., 2013; Sunday et al., 2011; Schlegel, et al., 2012), as well as to ocean warming and to both stressors combined (Foo et al., 2012)."

And so it would appear that a whole host of marine animals are well equipped, indeed, to deal with even the worst-case predictions of the world's climate-alarmists, as they pertain to ocean acidification and global warming.

Sherwood, Keith and Craig Idso

Amberg, M., Calosi, P., Spicer, J.I., Tandberg, A.H.S., Nilsen, M., Westerlund, S., Bechmann, R.K. 2014. Elevated temperature elicits greater effects than decreased pH on the development, feeding and metabolism of northern shrimp (Pandalus borealis) larvae. Marine Biology 10.1007/s22227-012-2072-9.

Byrne, M., Lamare, M., Winter, D., Dworjanyn, S.A. and Uthicke, S. 2014. The stunting effect of a high CO2 ocean on calcification and development in sea urchin larvae, a synthesis from the tropics to the poles. Philosophical Transactions of the Royal Society B 368: 10.1098/rstb.2012.0439.

Dupont, S., Dorey, N., Stumpp, M., Melzner, F. and Thorndyke, M. 2014. Long-term and trans-life-cycle effects of exposure to ocean acidification in the green sea urchin Strongylocentrotus droebachiensis. Marine Biology 10.1007/s00227-00012-01921-x.

Foo, S.A., Dworjanyn, S.A., Poore, A.G.B. and Byrne, M. 2012. Adaptive capacity of the habitat modifying sea urchin Centrostephanus rogersii to ocean warming and ocean acidification: performance of early embryos. PLOS ONE 7: e42497.

Johnson, L.G. and Babcock, R.C. 1994. Temperature and the larval ecology of the crown-of-thorns starfish, Acanthaster planci. Biological Bulletin 187: 304-308.

Kelly, M.W., Padilla, G. and Hofmann, G.E. 2013. Natural variation and the capacity to adapt to ocean acidification in the keystone sea urchin Strongylocentrotus purpuratus. Global Change Biology 29: 2536-2546.

Nguyen, HS., Doo, S., Soars, N.A. and Byrne, M. 2012. Noncalcifying larvae in a changing ocean: warming, not acidification/hypercapnia, is the dominant stressor on development of the sea star Meridiastra calcar. Global Change Biology 18: 2466-2476.

O'Connor, C. and Mulley, J.C. 1977. Temperature effects on periodicity and embryology, with observations on population genetics, of aqua-cultural echinoid Heliocidaris tuberculata. Aquaculture 12: 99-114.

Parker, L.M., Ross, P.M., O'Connor, W.A., Borysko, L., Raftos, D.A. and Portner, H.-O. 2012. Adult exposure influences offspring response to ocean acidification in oysters. Global Change Biology 18: 82-92.

Pespini, M.H., Sanford, E., Gaylord, B., Hill, T.M., Hosfelt, J.D., Jaris, H.K., LaVigne, M., Lenz, E.A., Russell, A.D., Young, M.K. and Palumbi, S.R. 2013. Evolutionary change during experimental ocean acidification. Proceedings of the National Academy of Sciences USA 110: 6937-6942.

Schlegel, P., Havenhand, J.N., Gillings, M.R. and Williamson, J.E. 2012. Individual variability in reproductive success determines winners and losers under ocean acidification: a case study with sea urchins. PLOS ONE 7: e53118.

Sunday, J.M., Crim, R.N., Harley, C.D.G. and Hart, M.W. 2011. Quantifying rates of evolutionary adaptation in response to ocean acidification. PLOS ONE 6: 222881.