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Abstract Ormia ochracea (Bigot 1889) is a phonotactic parasitoid fly that targets a variety of field cricket species as hosts for their developing young. Female flies locate their hosts by tracking a male cricket’s courtship song. Viviparous larvae are then deposited on or near the host which they then pierce and penetrate, completing larval development within the cricket’s abdomen. Here, we describe Ormia male and female reproductive tracts exposed through micro-surgery and imaged with a variety of microscopic techniques. We also describe for the first time, both embryonic and early larval development that takes place within the female flies’ “uterus.” Special note is made of the phenomenon of intra-uterine embryonic growth, and prospects for accessing gametes or germ-cells for molecular engineering are discussed. 

In the ciliate Tetrahymena thermophila, the BCD1 pattern-gene encodes a Beige-BEACH-domain protein that defines cortical organelle dimensions through regulated endocytic activity. Tetrahymena cells homozygous for a bcd1 loss-of-function mutation exhibit supernumerary cortical organelles including oral apparatuses, cytoprocts and contractile vacuole pores. Elements of the broadened cortical domain phenotype can be phenocopied by disrupting clathrin-mediated endocytosis, suggesting that exocytic membrane delivery is balanced by endocytic retrieval of cortical pattern determinants.. 

Abstract As single cells, ciliates build, duplicate, and even regenerate complex cortical patterns by largely unknown mechanisms that precisely position organelles along two cell‐wide axes: anterior–posterior and circumferential (left–right). We review our current understanding of intracellular patterning along the anterior–posterior axis in ciliates, with emphasis on how the new pattern emerges during cell division. We focus on the recent progress at the molecular level that has been driven by the discovery of genes whose mutations cause organelle positioning defects in the model ciliateTetrahymena thermophila. These investigations have revealed a network of highly conserved kinases that are confined to either anterior or posterior domains in the cell cortex. These pattern‐regulating kinases create zones of cortical inhibition that by exclusion determine the precise placement of organelles. We discuss observations and models derived from classical microsurgical experiments in large ciliates (includingStentor) and interpret them in light of recent molecular findings inTetrahymena. In particular, we address the involvement of intracellular gradients as vehicles for positioning organelles along the anterior‐posterior axis. 

COVID-19 lockdowns in early 2020 reduced human mobility, providing an opportunity to disentangle its effects on animals from those of landscape modifications. Using GPS data, we compared movements and road avoidance of 2300 terrestrial mammals (43 species) during the lockdowns to the same period in 2019. Individual responses were variable with no change in average movements or road avoidance behavior, likely due to variable lockdown conditions. However, under strict lockdowns 10-day 95th percentile displacements increased by 73%, suggesting increased landscape permeability. Animals’ 1-hour 95th percentile displacements declined by 12% and animals were 36% closer to roads in areas of high human footprint, indicating reduced avoidance during lockdowns. Overall, lockdowns rapidly altered some spatial behaviors, highlighting variable but substantial impacts of human mobility on wildlife worldwide.