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Abstract Marine bivalves are important components of ecosystems and exploited by humans for food across the world, but the intrinsic vulnerability of exploited bivalve species to global changes is poorly known. Here, we expand the list of shallow-marine bivalves known to be exploited worldwide, with 720 exploited bivalve species added beyond the 81 in the United Nations FAO Production Database, and investigate their diversity, distribution and extinction vulnerability using a metric based on ecological traits and evolutionary history. The added species shift the richness hotspot of exploited species from the northeast Atlantic to the west Pacific, with 55% of bivalve families being exploited, concentrated mostly in two major clades but all major body plans. We find that exploited species tend to be larger in size, occur in shallower waters, and have larger geographic and thermal ranges—the last two traits are known to confer extinction-resistance in marine bivalves. However, exploited bivalve species in certain regions such as the tropical east Atlantic and the temperate northeast and southeast Pacific, are among those with high intrinsic vulnerability and are a large fraction of regional faunal diversity. Our results pinpoint regional faunas and specific taxa of likely concern for management and conservation. 

We present a psychometric evaluation of the Cybersecurity Curriculum Assessment (CCA), completed by 193 students from seven colleges and universities. The CCA builds on our prior work developing and validating a Cybersecurity Concept Inventory (CCI), which measures students' conceptual understanding of cybersecurity after a first course in the area. The CCA deepens the conceptual complexity and technical depth expectations, assessing conceptual knowledge of students who had completed multiple courses in cybersecurity. We review our development of the CCA and present our evaluation of the instrument using Classical Test Theory and Item-Response Theory. The CCA is a difficult assessment, providing reliable measurements of student knowledge and deeper information about high-performing students.