Skeletal Ultrastructure in Some Articulate Cyclostome Bryozoans

The ultrastructure of the calcareous skeleton is described in 11 species of articulate cyclostome bryozoans with elastic joints. Ten species have interior walls comprising semi-nacreous and pseudofoliated fabrics without a precursory granular layer. Exterior walls consist of outer, finely granular and planar spherulitic layers, succeeded by semi-nacreous and pseudofoliated fabrics like those of interior walls. Outer fabrics are calcified as longitudinal strips, each corresponding to a planar sphcrulitic unit. Articulation surfaces comprise ring diaphragms of very fine granular fabric with concentric laminations. The semi-nacre of walls adjacent to ring diaphragms contains minute holes. Crisulipora occidentalis is unique in having interior walls of transverse fibres succeeded by pseudofoliated fabric, articulation surfaces festooned with deep pits but lacking well-differentiated ring diaphragms, and pseudopores containing sieve-like closure plates. The ultrastructure of most articulates resembles tubuliporine cyclostomes with dominantly semi-nacreous walls, although the lack of precursory granular fabric in the interior walls and the presence of subcircular tablets of semi-nacre (without six-fold sectoring) may be peculiar to articulates. In contrast, Crisulipora is more similar to other tubuliporines with transverse fibres. evidence which, together with other skeletal characters, suggests that Crisulipora evolved jointing independently of the rest of the articulate cyclostomes.     

Aspects of the Functional Morphology of the Lophophore in Articulate Brachiopods

Histologic studies made on three species of articulate brachiopodsprovide information on the structural integrity, epithelialspecialization and other cellular aspects of the lophophore.Similarities in staining properties of granular inclusions foundin the matrix with those found in epithelial modifications ofthe brachial trough and the bases of the filaments suggest movementbetween cells within the matrix and the epithelium. The natureof the granular inclusions raises the possibility of intracellulardigestion along the lophophore of these brachiopods.     

The Influence of the Digital Divide on Face Preferences in El Salvador: People without Internet Access Prefer More Feminine Men,More Masculine Women,and Women with Higher Adiposity

Previous studies on face preferences have found that online and laboratory experiments yield similar results with samples from developed countries, where the majority of the population has internet access. No study has yet explored whether the same holds true in developing countries, where the majority of the population does not have internet access. This gap in the literature has become increasingly important given that several online studies are now using cross-country comparisons. We therefore sought to determine if an online sample is representative of the population in the developing country of El Salvador. In studies of Hispanic men and women aged 18–25, we tested facial masculinity and adiposity preferences by collecting data in person as well as online. Our results showed that there were no differences in preferences between people who reported having internet access, whether they were tested online or in person. This provides evidence that testing style does not bias preferences among the same population. On the other hand, our results showed multiple differences in preferences between people who reported having internet access and people who reported not having internet access. More specifically, we found that people without internet access preferred more feminine men, more masculine women, and women with higher adiposity than people with internet access. We also found that people without internet access had fewer resources (e.g. running water) than people with internet access, suggesting that harshness in the environment may be influencing face preferences. These findings suggest that online studies may provide a distorted perspective of the populations in developing countries.