Developing and Optimizing RNA Isolation Methods from Avian Tissues

Investigating tissue-specific gene expression first requires RNA isolation. This research seeks to develop and optimize multiple methods of RNA extraction from blood and gonadal tissues in several different avian species, including house sparrows (Passer domesticus) and northern jacanas (Jacana spinosa). Method variations include RNAlater vs. flash freezing tissue, homogenizer vs. bashing beads, phase separation vs. Zymo kit, and various temperature and time settings for incubation. Establishing effective methods for avian investigation of RNA will allow us to research how differential gene expression relates to phenotypic behaviors

Multimodal models of animal sex in scientific literature: breaking binaries leads to a better understanding of ecology and evolution

‘Sex’ is often used to describe a suite of phenotypic and genotypic traits of an organism related to reproduction. However, not all these traits are necessarily linked, and the rhetorical collapse of variation into a single term elides much of the complexity inherent in reproductive phenotypes. We conducted a meta-analysis of scientific literature to investigate how terminology related sexual phenotypes changes over time. We find that the conflation of gender and sex has increased, and there is a mammalian bias in this conflation. We highlight how a more inclusive and expansive framework for sex can clarify studies of sexual diversity

Methane output of rabbits (Oryctolagus cuniculus) and guinea pigs (Cavia porcellus) fed a hay-only diet: Implications for the scaling of methane production with body mass in non-ruminant mammalian herbivores

It is assumed that small herbivores produce negligible amounts of methane, but it is unclear whether this is a physiological peculiarity, or simply a scaling effect. A respiratory chamber experiment was conducted with six rabbits (Oryctolagus cuniculus, 1.57 ± 0.31 kg body mass) and six guinea pigs (Cavia porcellus, 0.79 ± 0.07 kg) offered grass hay ad libitum. Daily dry matter (DM) intake and DM digestibility were 50 ± 6 g kg–0.75 d–1 and 55 ± 6 % in rabbits and 59 ± 11 g kg–0.75 d–1 and 61 ± 3 % in guinea pigs, respectively. Methane production was similar for both species (0.20 ± 0.10 L d–1 and 0.22 ± 0.08 L d–1) and represented 0.69 ± 0.32 and 1.03 ± 0.29 % of gross energy intake in rabbits and guinea pigs, respectively. In relation to body mass (BM) guinea pigs produced significantly more methane. The data on methane per unit of BM obtained in this study and from literature on methane output of elephant, wallabies and hyraxes all lay close to a regression line derived from roughage-fed horses, showing an increase in methane output with BM. The regression including all data was nearly identical to that based on the horse data only (methane production in horses [L d–1] = 0.18 body mass [kg]0.97 (95%CI 0.92–1.02)) and indicates linear scaling. Because feed intake typically scales to BM0.75, linear scaling of methane output translates into increasing energetic losses at increasing BM. Accordingly, the data collection indicates that an increasing proportion of ingested gross energy is lost because relative methane production increases with BM. Different from ruminants, such losses (1-2% of gross energy) appear too small in non-ruminant herbivores to represent a physiologic constraint on body size. Nevertheless, this relationship may represent a physiological disadvantage with increasing herbivore body size