The influence of seawater temperature on zooid size and growth rate in Pentapora fascialis (Bryozoa: Cheilostomata)

Evidence of El Niño/La Niña–Southern Oscillation Variability in the Neogene-Pleistocene of Panama Revealed by a New Bryozoan Assemblage-Based Proxy

“…For colonial animals like bryozoans, the relationship is expressed at the zooid level, and there is a reasonable body of evidence that zooid size is indeed inversely related to temperature. This evidence comes from diverse laboratory-reared material (e.g., Menon 1972, Hunter and Hughes 1994, Atkinson et al 2006, Amui-Vedel et al 2007, O'Dea et al 2007b, diverse field-collected material (e.g., Okamura 1987, O'Dea and Okamura 2000b, 2000c, O'Dea and Jackson 2002, O'Dea 2005, Lombardi et al 2006, and the growth of bryozoans in the field (O'Dea and Okamura 1999; see Okamura et al 2011 for further review) There are other factors that influence the ultimate size of zooids, the most obvious being species-specific colonial growth rules, such as the production of annual growth check lines (O'Dea andOkamura 2000b, O'Dea 2005, Okamura et al unpubl data), substrate irregularities, predation, and competition from other sessile encrusters, the influence of which can be minimized with the judicious rejection of randomly selected zooids as the approach requires (O'Dea andOkamura 2000a, O'Dea 2005). Salinity and food availability (Hageman et al 2009) have also been shown to influence zooid size, yet the effects are minimal in comparison with those of temperature (Okamura 1987, Hunter and Hughes 1994, O'Dea and Okamura 1999, 2000b, O'Dea 2005, O'Dea et al 2007b.…”

History of upwelling in the Tropical Eastern Pacific and the paleogeography of the Isthmus of Panama

“…Variation in zooid size in modern day bryozoans is significantly related to the MART in which the colony grew due to the inverse relationship between zooid size and ambient temperature (Menon, 1972; Okamura, 1987; Okamura and Bishop, 1988;Hunter and Hughes, 1994;O'Dea and Okamura, 1999, 2000a, 2000b, 2000cO'Dea, 2005;Lombardi et al, 2006;Amui-Vedel et al, 2007). MART is estimated by measuring the amount of intracolony zooid size variation in fossil bryozoans and applying it to the following linear equation:…”

Bryozoan growth and environmental reconstruction by zooid size variation

“…Similarly, mean zooid lengths of Pentapora fascialis showed a significant and negative correlation with mean annual temperature for colonies collected from 9 sites in the Mediterranean and the UK (Lombardi et al 2006). Conversely, Novosel et al (2004) found no systematic differences in zooid lengths between 2 sites in the North and South Adriatic that could be explained by temperature.…”

“…Lombardi et al (2006) demonstrated that the upright bifoliate species Pentapora fascialis produces larger zooids during the colder winter than during the warmer summer near Plymouth (UK) and Tino Island in the Mediterranean. In contrast, 138 the average zooid lengths of Cryptosula pallasiana from south Wales were significantly longer in July than in January, although there was no significant difference in zooid width (Amui-Vedel et al 2007).…”

“…In contrast, estimates of mean zooid size provide no environmental information on their own but require comparisons with mean zooid sizes of colonies from different environments (e.g. as in Okamura & Bishop 1988, Berning et al 2005, Lombardi et al 2006. (3) The approach can be used to charac-terise the ecology of present-day en vironments that are difficult to access or for which relevant temperature data are unavailable.…”