Welcome back to the Abstract! Here are the studies this week that balanced it out, performed evasive maneuvers, decorated a love shack, and bred inside bones.First, scientists discover a new \u201ctriple symmetry\u201d on Earth that nobody can explain. Then: female dolphins keep tabs on coercive males, bowerbirds turn urban trash into urbane treasure, and the housing opportunities provided by dead dinos.As always, for more of my work, check out my book First Contact: The Story of Our Obsession with Aliens, or subscribe to my personal newsletter the BeX Files.\u00a0Triple symmetry all across the skyZhang, Jianhao et al. \u201cEarth\u2019s east\u2013west albedo symmetry.\u201d Nature.Scientists have discovered an unexplained \u201ctriple symmetry\u201d in Earth\u2019s albedo, meaning its ability to reflect sunlight. The finding deepens the mystery of Earth\u2019s oddly-balanced brightness contrasts, which has been well documented in the near-perfectly matched albedos of the northern and southern hemispheres, despite the very different geographies of these two halves of the planet.Researchers led by Jianhao Zhang of the University of Colorado Boulder now report the existence of \u201ca unique and persistent east-west (E-W) albedo symmetry: the 27\u00b0\u2009E meridian divides the planet into an Eastern Hemisphere and a Western Hemisphere that reflect nearly identical amounts of sunlight,\u201d according to the team\u2019s study.\u00a0The hemispheres bisected by the 27\u00b0\u2009E meridian line have nearly-identical amounts of ice-free ocean, cloud cover, as well as planetary albedo, distinguishing this phenomenon as a \u201ctriple symmetry\u201d that is distinct from the equatorially divided north-south symmetry, which only has matching albedos.Zhang and his colleagues discovered the triple symmetry by examining 25 years of data (2001\u20132025) captured by NASA’s Clouds and the Earth’s Radiant Energy System (CERES) program. The satellite-mounted instruments measure the amount of solar energy Earth reflects back into space.\u00a0The east-west symmetry persisted over this dataset, with its greatest variations linked to the El Ni\u00f1o-Southern Oscillation (ENSO). For this reason, the team emphasized that the symmetry is essential to accurate projections on a rapidly warming world. Currently, \u201call models fail to capture\u2026the triple-symmetry feature,\u201d a problem that may be \u201dcontributing to the persistent uncertainty in climate projections,\u201d according to the study.As for what causes this symmetry, nobody knows. It could be just a strange coincidence, or even weirder, an unknown process of planetary equilibrium. As we reported last year, the north-south albedo symmetry may be fading as both hemispheres get darker, with more pronounced effects in the North, so scientists are leaning toward the weird coincidence hypothesis.\u00a0\u201cWe cannot yet rule out the possibility that these hemispheric symmetries are simply coincidental features of the present climate state,\u201d the team said in the study. \u201cThe importance of the E\u2013W symmetry discovery, however, is beyond the identification of another \u2018sweet spot\u2019 of the Earth system.\u201d\u201cIt offers a powerful\u2026constraint on state-of-the-art [Earth system models] and, more broadly, on our fundamental understanding of the Earth climate system,\u201d the researchers concluded.\u00a0In other news\u2026Bottlenose bullies get bad reputations\u00a0\u00a0Bouchard, Alice et al. \u201cFemale dolphins use individual vocal labels to track coercive males.\u201d Proceedings of the National Academy of Sciences.Female dolphins avoid sexually coercive males by keeping track of their signature whistles, according to scientists who observed how wild female Indo-Pacific bottlenose dolphins reacted to recorded playbacks of male vocalizations in the waters of Shark Bay, Australia.\u00a0To secure mating opportunities, coercive males \u201cwill bite, hit, or charge the female, chase her\u2026and produce threat vocalizations termed pops\u2014all to intimidate the female and control her movements,\u201d said researchers led by Alice Bouchard of the University of Bristol. \u201cIndeed, pops are only produced by males\u201d and act \u201cas an agonistic \u2018come-hither\u2019 signal, inducing the female to stay close to the popping male.\u201d\u00a0Who could have guessed the term \u201cpopping male\u201d could be so ominous? No wonder female dolphins keep them at fin\u2019s length. Along those lines, the team found that females showed aversive responses to the recorded whistles of males known to have been coercive in the past.Females appear to use \u201cindividual vocal labels to guide reproductive decision-making based on their experience of individual male behavior,\u201d according to the study. Call it a whistle campaign.Look at this stuff, isn\u2019t it neat? This is how I reproductively competeEvans, Caitlin F. and Kelley, Laura A. \u201cUrbanization alters courtship signals in male great bowerbirds.\u201d Royal Society Open Science.For every popping dolphin in the seas, there is a lover bird in the trees. For the male great bowerbird (Chlamydera nuchalis), the key to attracting females isn\u2019t biting or coercion, but the construction of elaborate shelters called bowers decorated with carefully selected trinkets for the enjoyment of potential mates.\u00a0Scientists have now discovered that urban bowerbirds may have an edge in their game compared to their rural counterparts, thanks to the dazzling decor options that can be upcycled from their city environments.\u00a0Male bowerbird poses in front of his love-nest of urban trinkets. Image: Caitlin EvansThe team catalogued nearly 4,000 decorations collected by Australian bowerbirds at Dreghorn Cattle Station, the rural site, and their urban counterparts in, literally, Townsville (the children\u2019s book writes itself). The results suggest that “urban males may represent an adaptive change to a more attractive display, and that rural males are restricted in their displays by the materials available in their environment.\u201d\u201cThe two most common decorations in rural areas were green glass and green leaves\/seeds, and in urban areas the two most common decorations were green glass and red wire,\u201d said authors Caitlin F. Evans and Laura A. Kelley of the University of Exeter, \u201cDecorations on urban bowers were over 10 times more likely to be anthropogenic\u2026than decorations on rural bowers.\u201d\u00a0While the city birds may have an easier time finding flashy ornaments, the use of plastics and other human-generated trash have posed dangers, such as entanglement or ingestion, for other species, though it has not been confirmed in bowerbirds. Glass shards and scarlet wires may make for beautiful displays, but never discount the risk of fatal attraction.\u00a0\u00a0I\u2019m so hungry, I could eat a titanosaurBela\u00fastegui, Zain et al. \u201cThe fossil record of insect bone bioerosion: Insights from titanosaur remains at Lo Hueco (Late Cretaceous, Spain) and implications for continental ichnofacies.\u201d Earth-Science Reviews.We\u2019ll end, as all things should, with a 30,000-pound feast. Titanosaurs, the largest family of animals ever to walk on land, were so enormous as adults that predators basically left them alone (though they made for easy pickings as youngsters).\u00a0But once these dinosaurs shuffled off their metric-ton mortal coils, their corpses were devoured by scavengers\u2014including small insects that bore into their bones, leaving permanent structures in their fossilized remains, known as \u201cichnofacies.\u201d\u00a0Beetle chambers carved into titanosaur armor. Image: Bela\u00fastegui, Zain et al.In a new study, paleontologists mapped out the pits, holes, burrows, and trails etched into Cretaceous titanosaur bones deposited in the exquisitely well-preserved Lo Hueco site in Cuenca, Spain. In particular, the results revealed idiosyncratic pupation chambers likely dug out by flesh-eating Cubiculum beetles to deposit larvae. The structures suggest that the dead dinos were exposed to open air for weeks on ancient floodplains as beetles were born and bred in their bones.\u201cGiven the size of the titanosaurs\u2026it is likely that at least part of their carcasses remained dry for long periods of time (several days and even months), and hence, to constitute a perfect scenario for insect colonization,\u201d said researchers led by Zain Bela\u00fastegui of the University of Barcelona. \u201cThe large size of the carcasses involved (i.e., tons of decaying organic matter) may support specific and stable ecosystems during long periods of time.\u201dIn other words, titanosaur skeletons served as luxury mansions long after their death, with beetle colonies etching in the equivalent of \u201cwe were here\u201d notes that have lasted for 70 million years.Thanks for reading! See you next week.<\/p>\n","protected":false},"excerpt":{"rendered":"