Lim, Norman (Norman T-Lon)

This study was part of a larger project to improve learning of undergraduate chemistry in Singapore through the use of self-authored three-tier multiple-choice questions (3TMCQs) and the giving/receiving of peer feedback. Specifically, we examined the quality of written feedback based on the classification by Hattie and Timperley (2007) that year 2 to 4 learners (N=31) gave each other on responses in their 3TMCQs (N=466 administered). It was found that the most common type of voluntary feedback given by test-makers was task (& self), followed by process (& self), self alone, and lastly regulation (& self) levels over seven chemistry courses. In addition, question type (based on revised Bloom’s Taxonomy) had a marginal effect on the quality of feedback received; instead, items answered incorrectly garnered higher quality feedback and were four times more important than the cognitive level of questions. Feedback quality given by more experienced students was also no better than those given by less experienced ones. While there is growing evidence supporting the self-authoring of questions and giving/receiving peer feedback to enhance learning at undergraduate levels, further research is warranted into the types of peer feedback that learners may receive when attempting different question formats.

We report the first chromosome-length genome assemblies for three species in the mammalian order Pholidota: the white-bellied, Chinese, and Sunda pangolins. Surprisingly, we observe extraordinary karyotypic plasticity within this order and, in female white-bellied pangolins, the largest number of chromosomes reported in a Laurasiatherian mammal: 2n = 114. We perform the first karyotype analysis of an African pangolin and report a Y-autosome fusion in white-bellied pangolins, resulting in 2n = 113 for males. We employ a novel strategy to confirm the fusion and identify the autosome involved by finding the pseudoautosomal region (PAR) in the female genome assembly and analyzing the 3D contact frequency between PAR sequences and the rest of the genome in male and female white-bellied pangolins. Analyses of genetic variability show that white-bellied pangolins have intermediate levels of genome-wide heterozygosity relative to Chinese and Sunda pangolins, consistent with two moderate declines of historical effective population size. Our results reveal a remarkable feature of pangolin genome biology and highlight the need for further studies of these unique and endangered mammals.