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Climate change portends significant harms to humans and biodiversity but public knowledge of relevant scientific information remains limited. As societal changes and investment are essential to addressing anthropogenic climate change, efforts to better promote both civic science literacy and public awareness of climate change impacts are urgently required. Popular scientific television programming provides one avenue for broad climate change communication efforts. Our pilot study seeks to evaluate the effects viewing a popular scientific television program, "Bill Nye Saves the World: The Earth is a hot mess" on both fact recall and personal perceptions. We surveyed undergraduate students enrolled in non-majors courses at two institutions of higher education, one large selective private university, and one community college with open enrollment before and after viewing this program. The survey contained both open-response questions and Likert-like ordinal responses intended to evaluate both fact recall and beliefs related to climate change. After viewing the program, student awareness of climate change impacts was improved, especially for topics emphasized by the program such as sea level rise. Student awareness of ocean acidification was extremely low prior to viewing the program, and improved dramatically, with most respondents aware that ocean acidification is already impacting marine life after viewing. Our pilot study suggests that scientific television programs may successfully promote awareness of climate change impacts and increase perceived personal relevance of climate change, but additional data from a larger and demographically broad population is required to test whether this result is more broadly applicable.

The Plio-Pleistocene turnover event in the western Atlantic following the closure of the Central American Seaway involved high rates of extinction for both gastropod and bivalve molluscs. This extinction was associated with declining nutrient conditions and has been presumed to be associated with a decrease in molluscan body size. Previous work which has been concordant with this expectation, however, has either focused on bivalves or not considered the effects of the recovery post extinction. In three phylogenetically diverse clades, we found that body-size evolution in gastropods across the turnover event is likely tied to ecology. One clade increased in size, one decreased, and another exhibited no substantial change. Individual species lineages exhibit a mixture of microevolutionary changes from the Pliocene to today. This study indicates that gastropod body-size evolution may be more complex than in bivalves, with ecology and other functional traits playing a significant role. Macroevolutionary processes, especially whether a clade re-radiated post extinction, were found to be important. Indeed, a low portion of extant diversity consists of survivors from clades that increased in size or have similar size distributions among their species relative to the Pliocene. [ABSTRACT FROM AUTHOR]

This article examines the concept of holes in philosophy and their practical implications in zoological morphology, specifically in gastropod shells. The authors introduce different types of openings in gastropod shells, such as the true umbilicus, pseudoumbilicus, and a newly identified opening called the hollow newel. They propose that the axial openings in gastropod shells be designated as hollow newels, which lack complete inner shell walls forming the columella. The authors compare this concept to spiral staircases without a central supporting pillar. The text explores the presence of a hole, known as the "HN," in certain gastropod shells, discussing its attachment points for muscles and various character states associated with this feature. The authors conducted a survey and found that HNs are primarily found in turritellids. The text also delves into the potential functions and evolutionary significance of the HN. Overall, the article emphasizes the need for further research and examination of physical specimens to gain a better understanding of gastropod evolution and ecology. [Extracted from the article]

Turritellid gastropods are among the most widespread, abundant, and diverse mollusks in Plio-Pleistocene deposits of the Atlantic coastal plain and Florida, with at least 46 species and subspecies described over almost two centuries. Yet the systematic status of these common fossil species and their phylogenetic relationships--to each other and to turritellids living today in the western Atlantic--have never been investigated in detail. We make use of recent molecular phylogenetic work on living turritellids and new analyses of shell characters to review the group from this time interval to the present in a comprehensive phylogenetic analysis and assessment of their evolutionary history in the region. We conclude that 20 fossil and two Recent species are valid. Four of these species are placed in the genus Torcula Gray, 1847; five in Caviturritella new genus, and eleven in "Turritella" sensu lato. We identify Torcula perattenuata as the likely direct ancestor of one of the two turritellid species living today off the southeastern U.S. coast, Torcula exoleta, and we elucidate the fossil record of the other extant species, "Turritella" perexilis (senior synonym of Turritella acropora). We show that Caviturritella was extirpated from the United States Gulf and Atlantic coastal plains in the Early Pleistocene but is still represented in the western Atlantic by the living species C. variegata in the southern Caribbean. We also present the first detailed treatment of Plio-Pleistocene turritellid fossils from Georgia. Our analysis shows that the Plio-Pleistocene Pinecrest beds of Florida contain 18 co-occurring turritellid species, which is the highest turritellid species diversity in one formation known in the fossil record. [ABSTRACT FROM AUTHOR]

We use scanning electron microscopy imaging to examine the shell microstructure of fossil and living species in five families of caenogastropods (Strombidae, Volutidae, Olividae, Pseudolividae, and Ancillariidae) to determine whether parallel or convergent evolution is responsible for the development of a unique caenogastropod trait, the extreme parietal callus (EPC). The EPC is defined as a substantial thickening of both the spire callus and the callus on the ventral shell surface such that it covers 50% or more of the surface. Caenogastropods as a whole construct the EPC convergently, using a variety of low-density, poorly organized microstructures that are otherwise uncommon in caenogastropod non-callus shell construction. Within clades, however, we see evidence for parallelism in decreased regulation in both the shell and callus microstructure. Low-density and poorly ordered microstructure—such as used for the EPC—uses less organic scaffolding and is less energetically expensive than normal shell microstructure. This suggests the EPC functions to rapidly and inexpensively increase shell thickness and overall body size. Tests of functional ecology suggest that the EPC might function both to defend against crushing predation through increased body size and dissipation of forces while aiding in shell orientation of highly mobile gastropods. These interpretations hinge on the current phylogenetic placement of caenogastropod families, emphasizing the essential contribution of phylogeny when interpreting homoplasy. [ABSTRACT FROM AUTHOR]

Relative to epicontinental seas, shallow, open-ocean settings are underrepresented in the Paleozoic record, and it is possible that higher taxa associated with these environments that appeared to diversify in the post-Paleozoic may have unpreserved Paleozoic histories. As an initial test of this possibility, we evaluated the statistical affinity for open-ocean--facing environments of two elements of the modern fauna that appear to diversify in the middle Mesozoic, the veneroid bivalves and the buccinoid gastropods, and showed that, indeed, Mesozoic genera in both groups had statistical propensities to occur in ocean-facing settings. In contrast, two groups with extensive Paleozoic fossil records had either an affinity for epicontinental seas (the terebratulid brachiopods), or showed no statistical preference for either setting (the mytilid bivalves). We conducted molecular clock analyses to estimate the divergence times of these taxa, and found that our estimates for the origin of terebratulids and mytilids in the Paleozoic were concordant with their known geological records. While our molecular estimate for the origin of the buccinoids was also concordant with their known record, with an estimated origin in the Jurassic, molecular data indicate that the veneroids originated in the Paleozoic, more than 200 m.y. before their first fossil appearance in the Mesozoic. This intriguing result raises the possibility that additional elements of the modern fauna with preferences for open-ocean--facing settings may have had more extensive Paleozoic histories than heretofore appreciated. [ABSTRACT FROM AUTHOR]