Transcriptome profiles of Anopheles gambiae harboring natural low-level Plasmodium infection reveal adaptive advantages for the mosquito

Anopheline mosquitoes are the sole vectors for the Plasmodium pathogens responsible for malaria, which is among the oldest and most devastating of human diseases. The continuing global impact of malaria reflects the evolutionary success of a complex vector-pathogen relationship that accordingly has been the long-term focus of both debate and study. An open question in the biology of malaria transmission is the impact of naturally occurring low-level Plasmodium infections of the vector on the mosquito’s health and longevity as well as critical behaviors such as host-preference/seeking. To begin to answer this, we have completed a comparative RNAseq-based transcriptome profile study examining the effect of biologically salient, salivary gland transmission-stage Plasmodium infection on the molecular physiology of Anopheles gambiae s.s. head, sensory appendages, and salivary glands. When compared with their uninfected counterparts, Plasmodium infected mosquitoes exhibit increased transcript abundance of genes associated with olfactory acuity as well as a range of synergistic processes that align with increased fitness based on both anti-aging and reproductive advantages. Taken together, these data argue against the long-held paradigm that malaria infection is pathogenic for anophelines and, instead suggests there are biological and evolutionary advantages for the mosquito that drive the preservation of its high vectorial capacity.

Olfaction-Related Factors Affecting Chemosensory Dream Content in a Sleep Laboratory

Mental activity in sleep often involves visual and auditory content. Chemosensory (olfactory and gustatory) experiences are less common and underexplored. The aim of the study was to identify olfaction-related factors that may affect the occurrence of chemosensory dream content. Specifically, we investigated the effects of all-night exposure to an ambient odour, participants’ appraisal of their current olfactory environment, their general propensity to notice odours and act on them (i.e., odour awareness), and their olfactory acuity. Sixty pre-screened healthy young adults underwent olfactory assessment, completed a measure of odour awareness, and spent three nights in weekly intervals in a sleep laboratory. The purpose of the first visit was to adapt to the experimental setting. On the second visit, half of them were exposed to the smell of vanillin or thioglycolic acid and the other half to an odourless control condition. On the third visit, they received control or stimulation in a balanced order. On each visit, data were collected twice: once from the first rapid eye movement (REM) stage that occurred after 3 a.m., and then shortly before getting up, usually from a non-REM stage. Participants were asked to report the presence of sensory dream content and to assess their current olfactory environment. Neither exposure, nor participants’ assessments of the ambient odour, or olfactory acuity affected reports of chemosensory dream content but they were more frequent in individuals with greater odour awareness. This finding may have implications for treatment when such experiences become unwanted or bothersome.

Transcriptome Profiles of Anopheles Gambiae Harboring Natural Low-Level Plasmodium Infection Reveal Adaptive Advantages For The Mosquito

Anopheline mosquitoes are the sole vectors for the Plasmodium pathogens responsible for malaria, which is among the oldest and most devastating of human diseases. The continuing global impact of malaria reflects the evolutionary success of a complex vector-pathogen relationship that accordingly has been the long-term focus of both debate and study. An open question in the biology of malaria transmission is the impact of naturally occurring low-level Plasmodium infections of the vector on the mosquito’s health and longevity as well as critical behaviors such as host-preference/seeking. To begin to answer this, we have completed a comparative RNAseq-based transcriptome profile study examining the effect of biologically salient, salivary gland transmission-stage Plasmodium infection on the molecular physiology of Anopheles gambiae s.s. head, sensory appendage, and salivary glands. When compared with their uninfected counterparts, Plasmodium infected mosquitoes exhibit increased transcript abundance of genes associated with olfactory acuity as well as a range of synergistic processes that align with increased fitness based on both anti-aging and reproductive advantages. Taken together, these data argue against the long-held paradigm that malaria infection is pathogenic for anophelines and, instead, suggests there are biological and evolutionary advantages for the mosquito that drive the preservation of its high vectorial capacity.

The World of Browsers

This chapter discusses the metabolism of giraffes. Giraffes obtain their energy and all the other nutrients needed to support their metabolism by browsing on leaves, fruits, and flowers of trees and shrubs. Wherever they live in Africa giraffes select browse from very few species but principally they browse plants of the Acacia clade. Typically their diet will contain ~15% protein, ~5% fat, ~30% fiber, and minerals, especially calcium and phosphorus, and will provide ~8500 kJ of energy per kilogram of dry matter eaten. Acquisition of browse is facilitated by the elongated shape of their heads, the anatomy of their atlanto-occipital joint, a long neck supported by a unique suspensory ligament, a long and flexible tongue, and high visual and olfactory acuity. The preferred height at which giraffes browse (~3 m) is higher than the height achievable by other browsers, is an advantage conferred by their shape, and is usual explanation for the evolution of their shape. Browse preferred by giraffes is protected from over-browsing by thorns, ants, and unpalatable plant secondary metabolites, especially tannins. Giraffes tolerate tannins partly by secretion of saliva rich in proline that binds tannins. Tannins are metabolized by a combination of a gene-based ability and a liver larger than it is in grazer-ruminants. Thorns are avoided but thick layers of keratin in the mouth and tongue provide protection. Browse containing ants also is avoided, but giraffes have well-developed anatomical protection for their faces especially their eyes and nostrils.

Transcriptome Profiles of Anopheles gambiae Harboring Natural Low-Level Plasmodium Infection Reveal Adaptive Advantages for the Mosquito

Anopheline mosquitoes are the sole vectors for the Plasmodium pathogens responsible for malaria, which is among the oldest and most devastating of human diseases. The continuing global impact of malaria reflects the evolutionary success of a complex vector-pathogen relationship that accordingly has been the long-term focus of both debate and study. An open question in the biology of malaria transmission is the impact of naturally occurring low-level Plasmodium infections of the vector on mosquito health and longevity as well as critical behaviors such as host-preference/seeking. To begin to answer this, we have completed a comparative RNAseq-based transcriptome profile study examining the effect of biologically salient, salivary gland transmission-stage Plasmodium infection on the molecular physiology of Anopheles gambiae s.s. head, sensory appendage, and salivary glands. When compared with their uninfected counterparts, Plasmodium infected mosquitoes exhibit increased transcript abundance of genes associated with olfactory acuity as well as a range of synergistic processes that align with increased fitness based on both anti-aging and reproductive advantages. Taken together, these data argue against the long-held paradigm that malaria infection is pathogenic for anophelines and, instead, suggests there are biological and evolutionary advantages for the mosquito that drive the preservation of its high vectorial capacity.

Tracking with Batek Hunter-Gatherers of Malaysia

Tropical hunting studies that focus on tracking – how signs are interpreted – are rarely done if at all. This paper provides a preliminary sketch of the tracking strategies and knowledge of Batek of Malaysia. Studies of hunter-gatherer tracking rely heavily on Liebenberg’s carefully observed documentation of San tracking, enriched by his own scientific expertise in faunal behavior. Of the three levels of tracking he mentions, simple tracking is unreliable for the Batek, simply because of the nature of tropical forests. The default mode is systematic tracking, carefully gathering information, and piecing together a multisensorial picture of where prey is to be found. Their visual, auditory, and olfactory acuity is exceptional and so is their vocabulary for expressing these states. Tracking for Batek is not limited to the interpretation of tracks, or, rather, the notion of tracks needs to be broadened, to include tracks that cannot be seen, but can be heard and smelt. Tracking is about multisensory engagement in the needs of the moment and deploying the skills to decide what is and is not relevant information. It is about performance.