36 research outputs found
Cockroaches Probably Cleaned Up after Dinosaurs
Dinosaurs undoubtedly produced huge quantities of excrements. But who cleaned up after them? Dung beetles and flies with rapid development were rare during most of the Mesozoic. Candidates for these duties are extinct cockroaches (Blattulidae), whose temporal range is associated with herbivorous dinosaurs. An opportunity to test this hypothesis arises from coprolites to some extent extruded from an immature cockroach preserved in the amber of Lebanon, studied using synchrotron X-ray microtomography. 1.06% of their volume is filled by particles of wood with smooth edges, in which size distribution directly supports their external pre-digestion. Because fungal pre-processing can be excluded based on the presence of large particles (combined with small total amount of wood) and absence of damages on wood, the likely source of wood are herbivore feces. Smaller particles were broken down biochemically in the cockroach hind gut, which indicates that the recent lignin-decomposing termite and cockroach endosymbionts might have been transferred to the cockroach gut upon feeding on dinosaur feces
Insecticide-induced leg loss does not eliminate biting and reproduction in Anopheles gambiae mosquitoes
âSomething fruitful for all of usâ: Social annotation as a signature pedagogy for literature education
Circatidal swimming activity rhythm in a subtidal cumacean Dimorphostylis asiatica (Crustacea)
Circalunidian clocks control tidal rhythms of locomotion in the American horseshoe crab, Limulus polyphemus
The activation of Ca2+-dependent K+ conductance by adrenaline in mouse peritoneal macrophages
Mechanistic Insight into the H2O/D2O Isotope Effect in the Proton Transport of the Influenza Virus M2 Protein
Ganglion-specific splicing of TRPV1 underlies infrared sensation in vampire bats
Vampire bats (Desmodus rotundus) are obligate blood feeders that have evolved specialized systems to suit their unique sanguinary lifestyle (1â3). Chief among such adaptations is the ability to detect infrared radiation as a means of locating hot spots on warm-blooded prey. Among vertebrates, only vampire bats, boas, pythons, and pit vipers are capable of detecting infrared radiation (1,4). In each case, infrared heat is detected by trigeminal nerve fibers that innervate specialized pit organs on the animalâs face (5â10). Thus, vampire bats and snakes have taken thermosensation to the extreme by developing specialized systems for detecting infrared radiation. As such, these creatures provide a window into the molecular and genetic mechanisms underlying evolutionary tuning of thermoreceptors in a species or cell type specific manner. Previously, we have shown that snakes co-opt a non-heat sensitive channel (vertebrate TRPA1) to produce an infrared detector (6). Here we show that vampire bats tune an already heat sensitive channel (TRPV1) by lowering its thermal activation threshold to ~30°C. This is achieved through alternative splicing of TRPV1 transcripts to produce a channel with a truncated C-terminal cytoplasmic domain. Remarkably, these splicing events occur exclusively in trigeminal ganglia (TG), and not dorsal root ganglia (DRG), thereby maintaining a role for TRPV1 as a detector of noxious heat in somatic afferents. This reflects a unique organization of the bat TRPV1 gene that we show to be characteristic of Laurasiatheria mammals (cows, dogs, and moles), supporting a close phylogenetic relationship with bats. These findings reveal a unique molecular mechanism for physiological tuning of thermosensory nerve fibers
Shakespeare, William
William Shakespeare (1564â1616) is the worldâs most highly acclaimed literary figure, known for his plays and poems. Shakespeare is celebrated for his comic touch; kaleidoscopic, tightly structured verse; and genial sense of human nature, manifest in finely detailed individual characterization. Less widely recognized, however, is the depth of his engagement with classical and contemporary philosophy, which bears comparison to more obviously learned contemporaries such as Michel de Montaigne (1533â1592), John Case (c. 1540â1600), and Justus Lipsius (1547â1606)