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Categories: Biology: Evolutionary, Offbeat: Earth and Climate
Published 3D mouth of an ancient jawless fish suggests they were filter-feeders, not scavengers or hunters
(via sciencedaily.com) Original source Early jawless fish were likely to have used bony projections surrounding their mouths to modify the mouth's shape while they collected food. Experts have used CT scanning techniques to build up the first 3D pictures of these creatures, which are some of the earliest vertebrates (animals with backbones) in which the mouth is fossilized. Their aim was to answer questions about feeding in early vertebrates without jaws in the early Devonian epoch -- sometimes called the Age of Fishes -- around 400 million years ago.
Published Birdfeeders are designed to keep unwanted guests away
(via sciencedaily.com) Original source The first birdfeeders were made in the 19th century, and their design rapidly evolved during the 20th century. Researchers at the consider the evolution of the birdfeeder to be an example of multispecies design, where unwanted guests have shaped the human-made artifact.
Published 'Teacher Toads' can save native animals from toxic cane toads
(via sciencedaily.com) Original source Scientists from Macquarie University have come up with an innovative way to stop cane toads killing native wildlife by training goannas to avoid eating the deadly amphibians.
Published Toothed whale echolocation organs evolved from jaw muscles
(via sciencedaily.com) Original source Genetic analysis finds evidence suggesting that acoustic fat bodies in the heads of toothed whales were once the muscles and bone marrow of the jaw.
Published Mediterranean marine worm has developed enormous eyes
(via sciencedaily.com) Original source Scientists are amazed at the discovery of a bristle worm with such sharp-seeing eyes that they can measure up to those of mammals and octopuses. The researchers suspect that these marine worms may have a secretive language, which uses UV light only seen by their own species. The advanced vision of such a primitive creature helps to finally settle an epic debate about the evolution of eyes.
Published In the evolution of walking, the hip bone connected to the rib bones
(via sciencedaily.com) Original source A new reconstruction of the 375-million-year-old fossil fish Tiktaalik -- a close relative of limbed vertebrates -- used micro-CT to reveal bones still embedded in matrix. The reconstruction shows that the fish's ribs likely attached to its pelvis, an innovation thought to be crucial to supporting the body and for the eventual evolution of walking.
Published Dinosaur study challenges Bergmann's rule
(via sciencedaily.com) Original source A new study calls into question Bergmann's rule, an 1800s-era scientific principle stating that animals in high-latitude, cooler climates tend to be larger than close relatives living in warmer climates.
Published The life aquatic: A game changer for frog vision, but little difference between night and day
(via sciencedaily.com) Original source Frogs display a remarkable diversity of species as a whole, but does the same hold true for their visual abilities? A new study sought to answer this question by collaborating with researchers in Australia, Belgium, Brazil, Cameroon, Ecuador, Equatorial Guinea, French Guiana, Gabon, Seychelles, Sweden, United Kingdom and the United States, to get a sample of a diverse array of frogs to study the visual pigments found in their eyes. The researchers found this diversity is largely 'reflected' in the pigments, especially for aquatic frogs versus those living on the ground or in trees. They found little difference with the small groups of frogs that have adapted to daytime conditions as opposed to their nocturnal cousins.
Published Finds at Schöningen show wood was crucial raw material 300,000 years ago
(via sciencedaily.com) Original source During archaeological excavations in the Schoningen open-cast coal mine in 1994, the discovery of the oldest, remarkably well-preserved hunting weapons known to humanity caused an international sensation. Spears and a double-pointed throwing stick were found lying between animal bones about ten meters below the surface in deposits at a former lakeshore. In the years that followed, extensive excavations have gradually yielded numerous wooden objects from a layer dating from the end of a warm interglacial period 300,000 years ago. The findings suggested a hunting ground on the lakeshore.
Published Researchers envision sci-fi worlds involving changes to atmospheric water cycle
(via sciencedaily.com) Original source Human activity is changing the way water flows between the Earth and atmosphere in complex ways and with likely long-lasting consequences that are hard to picture. Researchers enlisted water scientists from around the globe to write story-based scenarios about the possible futures humanity is facing but perhaps can't quite comprehend yet. The results are part of a creative pathway to understand atmospheric water research with an eye towards the potential economic and policy issues that may be just beyond the horizon.
Published New sunflower family tree reveals multiple origins of flower symmetry
(via sciencedaily.com) Original source A new sunflower family tree used skimmed genomes to increase the number of species sampled, revealing that flower symmetry evolved multiple times independently, a process called convergent evolution, among the members of this large plant family.
Published Evolution in action? New study finds possibility of nitrogen-fixing organelles
(via sciencedaily.com) Original source A new study finds that UCYN-A, a species of nitrogen-fixing cyanobacteria, may be evolving organelle-like characteristics.
Published Giant phage holds promise as treatment for lung infections
(via sciencedaily.com) Original source Researchers have discovered a new bacterial killer that can target common lung infection caused by Burkholderia bacteria that has exciting potential for biotechnological applications.
Published First view of centromere variation and evolution
(via sciencedaily.com) Original source A genomic study of human and selected nonhuman primate centromeres has revealed their unimaginable diversity and speed of evolutionary change. Although centromeres are vital to proper cell replication by assuring faithful transmision of genetic materials when cells divide, the complexity of their genomic organization had been almost impossible to study. The lack of centromere sequences hindered exploration of how these regions help maintain genetic integrity. Now, advanced technologies have shown scientists how greatly centromeres differ in size and structure.
Published Elastocaloric cooling: Refrigerator cools by flexing artificial muscles
(via sciencedaily.com) Original source There is room for just one small bottle in the world's first refrigerator that is cooled with artificial muscles made of nitinol, a nickel-titanium alloy. But the mini-prototype is groundbreaking: it shows that elastocalorics is becoming a viable solution for practical applications. This climate-friendly cooling and heating technology is far more energy-efficient and sustainable than current methods.
Published These plants evolved in Florida millions of years ago: They may be gone in decades
(via sciencedaily.com) Original source Scrub mints are among the most endangered plants you've probably never heard of. More than half of the 24 species currently known to exist are considered threatened or endangered at the state or federal level. In a new study, researchers show there are likely more scrub mint species waiting to be scientifically described. And at least one species has been left without federal protection because of a technicality.
Published AI writing, illustration emits hundreds of times less carbon than humans, study finds
(via sciencedaily.com) Original source A group of scholars calculated the amount of energy used by AI tools for the tasks of writing and illustrating and compared it to the average amount of energy humans use for the same processes. Their results showed artificial intelligence results in hundreds of times less carbon emissions than humans. This does not mean, however, that AI can or should replace humans in those tasks, simply that its energy usage is less. The better approach is a partnership between humans and AI, the authors write.
Published We've had bird evolution all wrong
(via sciencedaily.com) Original source Genomic anamolies dating back to the time of the dinosaurs misled scientists about the evolutionary history of birds.
Published Computational tools fuel reconstruction of new and improved bird family tree
(via sciencedaily.com) Original source Using cutting-edge computational methods and supercomputing infrastructure, researchers have built the largest and most detailed bird family tree to date -- an intricate chart delineating 93 million years of evolutionary relationships between 363 bird species, representing 92% of all bird families. The updated tree reveals sharp increases in effective population size, substitution rates and relative brain size in early birds in the aftermath of the mass extinction event that wiped out the dinosaurs 66 million years ago. And by closely examining one of the branches of this tree, researchers found that flamingos and doves are more distantly related than previous genome-wide analyses had shown.
Published When inequality is more than 'skin-deep': Social status leaves traces in the epigenome of spotted hyenas in Tanzania
(via sciencedaily.com) Original source A research consortium provides evidence that social behavior and social status are reflected at the molecular level of gene activation (epigenome) in juvenile and adult free-ranging spotted hyenas. They analyzed non-invasively collected gut epithelium samples from both high-ranking and low-ranking female hyenas and showed that rank differences were associated with epigenetic signatures of social inequality, i.e., the pattern of activation or switching off of genes that regulate important physiological processes such as energy conversion and immune response in several genome regions.