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As we look for traces of ancient life on Mars, we need to consider the impact of ionizing radiation in the biosignature preservation process. Here, we irradiated two organic rich terrestrial samples (Enspel and Messel shales) that have Martian analog mineralogies, with simulated cosmic rays to a dose of 0.9 MGy, equivalent of 15 million years of radiation exposure on the Martian surface. We compared a range of biosignatures before and after exposure, including total organic carbon, bulk stable carbon isotope ratios, diagnostic lipid biomarkers (hopanes and steranes), and Raman signatures akin to those collected by the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument on Perseverance. While we did not observe a significant difference in total organic carbon, bulk stable carbon isotopes, or Raman G-band signatures, we found that five lipid biomarkers decreased by a factor of two to three in the Enspel shale. This degree of degradation exceeds current predictions by existing models or experimental studies in organic rich samples and challenges our current understanding of complex biosignatures under ionizing irradiation. 

As high school computer science course offerings have expanded over the past decade, gaps in race and gender have remained. This study embraces the “All” in the “CS for All” movement by shifting beyond access and toward abolitionist computer science teaching. Using data from professional development observations and interviews, we lift the voices of BIPOC CS teachers and bring together tenets put forth by Love (2019) for abolitionist teaching along with how these tenets map onto the work occurring in CS classrooms. Our findings indicate the importance of BIPOC teacher representation in CS classrooms and ways abolitionist teaching tenets can inform educator’s efforts at moving beyond broadening participation and toward radical inclusion, educational freedom, and self-determination, for ALL. 

The Bahama Oriole (Icterus northropi) is a Critically Endangered species restricted to Andros in The Bahamas. Previous research suggested that the Bahama Oriole nested almost exclusively in coconut palms (Cocos nucifera) in developed habitats. In 2016, however, the Bahama Oriole was documented nesting in remote pine forests for the first time. Our goals were to document where orioles nest in pine forests and to characterize nest site vegetation to determine if orioles show a preference for specific habitat characteristics. Here, we document 12 pine forest nests: six nests in understory Key thatch palms (Leucothrinax morrisii) and six nests in Caribbean pines (Pinus caribaea). For each nest tree, we measured the tree height, tree diameter, and nest height. We also took measurements of habitat characteristics in 10-m and 100-m radius plots around the nest and compared these measurements to control plots. Orioles nested in a range of pine forest habitats. However, on average, Bahama Orioles nested in pine forests with more tall thatch palms (> 2 m tall) in the understory compared to control plots. They also tended to nest in the tallest thatch palms in the understory. The findings from this study further support the importance of protecting Bahamian pine forests on Andros. 

We studied Native American college students’ perceptions of educational barriers and supports while pursuing degrees leading to careers in engineering. Based on findings from our qualitative study, we provide recommendations for students, professors, departments, and institutions on how to support Native American students to be successful as they pursue careers in science, math, and engineering careers. 

Science, technology, engineering, and mathematics (STEM) education initiatives in higher education increasingly call for career mentorship opportunities for underrepresented minorities (URM). Researchers (Johnson & Sheppard, 2004; Nelson & Brammer, 2010) note the importance of having faculty to mentor and act as role models for students, often assuming that mentors play a stronger role if they are also from the same cultural background. Native American (NA) faculty members are underrepresented in most fields in colleges and universities, and exceedingly so in engineering. Only 0.2% (N=68) of engineering faculty nationwide identify as Native American (Yoder, 2014). Likewise, NA students are underrepresented in undergraduate (0.6%; N=1853) and graduate (0.1%; N=173) engineering programs. The low percentage in graduate school is of even greater concern as they represent the primary potential pool of new faculty members. Advising and mentorship from those who identify as NA are often considered important components recruiting and retention in STEM fields. For example, Smith and colleagues (2014) found that factors such as communal goal orientation influenced NA engineering students’ motivation and academic performance. However, very few studies account for differences in NA identity or provide a nuanced account of successful NA STEM professional experiences (Page-Reeves et al., 2018). This research paper presents findings from an exploratory study aimed at pinpointing the factors that influence NA entry and persistence in engineering faculty positions.