The genome of the water strider Gerris buenoi reveals expansions of gene repertoires associated with adaptations to life on the water.

Background: Having conquered water surfaces worldwide, the semi-aquatic bugs occupy ponds, streams, lakes, mangroves, and even open oceans. The diversity of this group has inspired a range of scientific studies from ecology and evolution to developmental genetics and hydrodynamics of fluid locomotion. However, the lack of a representative water strider genome hinders our ability to more thoroughly investigate the molecular mechanisms underlying the processes of adaptation and diversification within this group.

Social regulation of a rudimentary organ generates complex worker-caste systems in ants.

The origin of complex worker-caste systems in ants perplexed Darwin and has remained an enduring problem for evolutionary and developmental biology. Ants originated approximately 150 million years ago, and produce colonies with winged queen and male castes as well as a wingless worker caste. In the hyperdiverse genus Pheidole, the wingless worker caste has evolved into two morphologically distinct subcastes-small-headed minor workers and large-headed soldiers.

Analysis of decreases in systemic arterial pressure and heart rate in response to the hydrogen sulfide donor sodium sulfide.

The actions of hydrogen sulfide (HS) on the heart and vasculature have been extensively reported. However, the mechanisms underlying the effects of HS are unclear in the anesthetized rat. The objective of the present study was to investigate the effect of HS on the electrocardiogram and examine the relationship between HS-induced changes in heart rate (HR), mean arterial pressure (MAP), and respiratory function.