Biology Instructors See Value in Discussing Controversial Topics but Fear Personal and Professional Consequences.

Traditional biology curricula depict science as an objective field, overlooking the important influence that human values and biases have on what is studied and who can be a scientist. We can work to address this shortcoming by incorporating ideological awareness into the curriculum, which is an understanding of biases, stereotypes, and assumptions that shape contemporary and historical science. We surveyed a national sample of lower-level biology instructors to determine 1) why it is important for students to learn science, 2) the perceived educational value of ideological awareness in the classroom, and 3) hesitancies associated with ideological awareness implementation. We found that most instructors reported "understanding the world" as the main goal of science education. Despite the perceived value of ideological awareness, such as increasing student engagement and dispelling misconceptions, instructors were hesitant to implement ideological awareness modules due to potential personal and professional consequences.

Why Students Struggle in Undergraduate Biology: Sources and Solutions.

Students' perceptions of challenges in biology influence performance outcomes, experiences, and persistence in science. Identifying sources of student struggle can assist efforts to support students as they overcome challenges in their undergraduate educations. In this study, we characterized student experiences of struggle by 1) quantifying which external factors relate to perceptions of encountering and overcoming struggle in introductory biology and 2) identifying factors to which students attribute their struggle in biology. We found a significant effect of Course, Instructor, and Incoming Preparation on student struggle, in which students with lower Incoming Preparation were more likely to report struggle and the inability to overcome struggle. We also observed significant differences in performance outcomes between students who did and did not encounter struggle and between students who did and did not overcome their struggle. Using inductive coding, we categorized student responses outlining causes of struggle, and using axial coding, we further categorized these as internally or externally attributed factors. External sources (i.e., Prior Biology, COVID-19, External Resources, Classroom Factors) were more commonly cited as the reason(s) students did or did not struggle. We conclude with recommendations for instructors, highlighting equitable teaching strategies and practices.

Reduced Mitochondrial Respiration in Hybrid Asexual Lizards.

AbstractThe scarcity of asexual reproduction in vertebrates alludes to an inherent cost. Several groups of asexual vertebrates exhibit lower endurance capacity (a trait predominantly sourced by mitochondrial respiration) compared with congeneric sexual species. Here we measure endurance capacity in five species of Aspidoscelis lizards and examine mitochondrial respiration between sexual and asexual species using mitochondrial respirometry. Our results show reduced endurance capacity, reduced mitochondrial respiration, and reduced phenotypic variability in asexual species compared with parental sexual species, along with a positive relationship between endurance capacity and mitochondrial respiration. Results of lower endurance capacity and lower mitochondrial respiration in asexual Aspidoscelis are consistent with hypotheses involving mitonuclear incompatibility.

A chromosome-level genome assembly for the eastern fence lizard (Sceloporus undulatus), a reptile model for physiological and evolutionary ecology.

BACKGROUND: High-quality genomic resources facilitate investigations into behavioral ecology, morphological and physiological adaptations, and the evolution of genomic architecture. Lizards in the genus Sceloporus have a long history as important ecological, evolutionary, and physiological models, making them a valuable target for the development of genomic resources. FINDINGS: We present a high-quality chromosome-level reference genome assembly, SceUnd1.0 (using 10X Genomics Chromium, HiC, and Pacific Biosciences data), and tissue/developmental stage transcriptomes for the eastern fence lizard, Sceloporus undulatus. We performed synteny analysis with other snake and lizard assemblies to identify broad patterns of chromosome evolution including the fusion of micro- and macrochromosomes. We also used this new assembly to provide improved reference-based genome assemblies for 34 additional Sceloporus species. Finally, we used RNAseq and whole-genome resequencing data to compare 3 assemblies, each representing an increased level of cost and effort: Supernova Assembly with data from 10X Genomics Chromium, HiRise Assembly that added data from HiC, and PBJelly Assembly that added data from Pacific Biosciences sequencing. We found that the Supernova Assembly contained the full genome and was a suitable reference for RNAseq and single-nucleotide polymorphism calling, but the chromosome-level scaffolds provided by the addition of HiC data allowed synteny and whole-genome association mapping analyses. The subsequent addition of PacBio data doubled the contig N50 but provided negligible gains in scaffold length. CONCLUSIONS: These new genomic resources provide valuable tools for advanced molecular analysis of an organism that has become a model in physiology and evolutionary ecology.

Rivers of Indochina as potential drivers of lineage diversification in the spotted flying lizard (Draco maculatus) species complex.

Southeast Asia hosts a rich concentration of biodiversity within multiple biodiversity hotspots. Indochina, a region with remarkably high levels of in situ diversification, possesses five major rivers (Ayeyarwady, Chiang Mai, Mekong, Red, and Salween), several of which coincide with phylogenetic breaks of terrestrial taxa. Draco maculatus possesses a range that stretches across Indochina, which widespread geographic distribution along with potential discrete variation within subspecies alludes to the possibility of this taxon constituting multiple divergent lineages. Using sequence data from three mitochondrial (12S, 16S, and ND2) and three nuclear (BDNF, CMOS, and PNN) genes, we provide the first estimated phylogeny of this hypothesized species complex and examine its phylogeographic architecture with maximum likelihood and Bayes factor delimitation (BFD) approaches. Our results support multiple divergent lineages with phylogenetic breaks coincident with rivers, indicating that river barriers may be contributing to the elevated levels of in situ diversification of Indochina.

The phylogenetic relationships of a new Stream Toad of the genus Ansonia Stoliczka, 1870 (Anura: Bufonidae) from a montane region in Peninsular Malaysia.

Twelve species of Ansonia occur on the Thai-Malay peninsula, of which, five from Peninsular Malaysia, form a monophyletic group. One of these, A. jeetsukumarani, is endemic to the Titiwangsa Mountain Range, in which, we discovered a new population of Ansonia that is not A. jeetsukumarani or even its closest relative. Based on morphology, color pattern, and molecular phylogenetic analyses using the mitochondrial genes 12s and 16s rRNA, we have determined that this new species, A. smeagol sp. nov., forms the sister lineage to an upland, monophyletic group composed of A. jeetsukumarani, A. lumut, A. malayana, and A. penangensis. We have noted similar biogeographic patterns in other taxa from the Titiwangsa Mountain Range in a number of upland lineages in Peninsular Malaysia. We hypothesize that the phylogeographic structure of these upland populations is a result of stochastic processes stemming from interaction of climate-driven forest dynamics and life histories.