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Over thousands of years, Indigenous hunters in the Bering and Chukchi seas have adapted to changes in weather, sea ice, and sea state that influence their access to walruses. In recent decades, 10 however, those conditions have been changing at unprecedented rates. Safely adapting to changing conditions will be essential to the well-being of communities. 

While a standard calculus course may include some neatly-packaged applications of rate of change or Riemann sums to problems of kinematics, majors from biology and medicine are in urgent need of mathematics taught from a modeling perspective. Yet, the art of modeling is scarce in tertiary mathematics classrooms in part because, much like in schools, many mathematicians may lack (a) the relevant real-world concepts (beyond simple physics and engineering) (b) knowledge of the mathematics from a modeling perspective or (c) confidence to change their classroom practices. To remedy this, we trialed a professional development workshop for faculty to learn to mathematically model biological contexts with dynamical systems. The workshop enacted the field’s recommendations for professional development with teachers. We observed gains in faculty’s self-reported comfort with mathematics and biology concepts and teaching mathematics with a modeling perspective. 

Comparative genomics has enabled the identification of genes that potentially evolved de novo from non-coding sequences. Many such genes are expressed in male reproductive tissues, but their functions remain poorly understood. To address this, we conducted a functional genetic screen of over 40 putative de novo genes with testis-enriched expression in Drosophila melanogaster and identified one gene, atlas , required for male fertility. Detailed genetic and cytological analyses showed that atlas is required for proper chromatin condensation during the final stages of spermatogenesis. Atlas protein is expressed in spermatid nuclei and facilitates the transition from histone- to protamine-based chromatin packaging. Complementary evolutionary analyses revealed the complex evolutionary history of atlas . The protein-coding portion of the gene likely arose at the base of the Drosophila genus on the X chromosome but was unlikely to be essential, as it was then lost in several independent lineages. Within the last ~15 million years, however, the gene moved to an autosome, where it fused with a conserved non-coding RNA and evolved a non-redundant role in male fertility. Altogether, this study provides insight into the integration of novel genes into biological processes, the links between genomic innovation and functional evolution, and the genetic control of a fundamental developmental process, gametogenesis.