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Categories: Biology: Developmental, Paleontology: Fossils
Published Homo sapiens likely arose from multiple closely related populations
(via sciencedaily.com) Original source In testing the genetic material of current populations in Africa and comparing against existing fossil evidence of early Homo sapiens populations there, researchers have uncovered a new model of human evolution -- overturning previous beliefs that a single African population gave rise to all humans.
Published Researchers reveal DNA repair mechanism
(via sciencedaily.com) Original source A new study adds to an emerging, radically new picture of how bacterial cells continually repair faulty sections of their DNA.
Published A look inside stem cells helps create personalized regenerative medicine
(via sciencedaily.com) Original source Researchers have examined a specific type of stem cell with an intracellular toolkit to determine which cells are most likely to create effective cell therapies.
Published A jumping conclusion: Fossil insect ID'd as new genus, species of prodigious leaper, the froghopper
(via sciencedaily.com) Original source A fossil arthropod entombed in 100-million-year-old Burmese amber has been identified as a new genus and species of froghopper, known today as an insect with prodigious leaping ability in adulthood following a nymphal stage spent covered in a frothy fluid.
Published A journey to the origins of multicellular life: Long-term experimental evolution in the lab
(via sciencedaily.com) Original source Over 3,000 generations of laboratory evolution, researchers watched as their model organism, 'snowflake yeast,' began to adapt as multicellular individuals. In new research, the team shows how snowflake yeast evolved to be physically stronger and more than 20,000 times larger than their ancestor. Their study is the first major report on the ongoing Multicellularity Long-Term Evolution Experiment (MuLTEE), which the team hopes to run for decades.
Published Basic 'toolkit' for organ development is illuminated by sea star
(via sciencedaily.com) Original source One of the basic and crucial embryonic processes to unfold in virtually every living organism is the formation of hollow, tubular structures that go on to form blood vessels or a digestive tract, and through branching and differentiation, complex organs including the heart and kidneys. This study illuminates fundamental design principles of tubulogenesis for all chordates, including mammals.
Published Earth's first animals had particular taste in real estate
(via sciencedaily.com) Original source Even without body parts that allowed for movement, new research shows -- for the first time -- that some of Earth's earliest animals managed to be picky about where they lived.
Published T cells can activate themselves to fight tumors
(via sciencedaily.com) Original source Scientists find an auto-signaling mechanism driving the T cell anti-tumor response; findings may inspire new cancer therapeutics and biomarkers.
Published An unprecedented view of gene regulation
(via sciencedaily.com) Original source Using a new technique, researchers have shown that they can map interactions between gene promoters and enhancers with 100 times higher resolution than has previously been possible.
Published Elucidating the mysteries of enzyme evolution at the macromolecular level
(via sciencedaily.com) Original source Researchers have made a major breakthrough earlier this year in the field of evolutionary conservation of molecular dynamics in enzymes. Their work points to potential applications in health, including the development of new drugs to treat serious diseases such as cancer or to counter antibiotic resistance.
Published The evolution of honey bee brains
(via sciencedaily.com) Original source Researchers have proposed a new model for the evolution of higher brain functions and behaviors in the Hymenoptera order of insects. The team compared the Kenyon cells, a type of neuronal cell, in the mushroom bodies (a part of the insect brain involved in learning, memory and sensory integration) of 'primitive' sawflies and sophisticated honey bees. They found that three diverse, specialized Kenyon cell subtypes in honey bee brains appear to have evolved from a single, multifunctional Kenyon cell-subtype ancestor. In the future, this research could help us better understand the evolution of some of our own higher brain functions and behaviors.
Published Happy worms have healthy eggs
(via sciencedaily.com) Original source Researchers have exposed roundworms (a well-established model organism in biological research) to selective serotonin reuptake inhibitors (SSRIs), a class of drugs used for treating depression and anxiety. Surprisingly, this treatment improved the quality of aging females' egg cells.
Published Scientists discover the dynamics of an 'extra' chromosome in fruit flies
(via sciencedaily.com) Original source Most chromosomes have been around for millions of years. Now, researchers have revealed the dynamics of a new, very young chromosome in fruit flies that is similar to chromosomes that arise in humans and is associated with treatment-resistant cancer and infertility. The findings may one day lead to developing more targeted therapies for treating these conditions.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.
Published New tusk-analysis techniques reveal surging testosterone in male woolly mammoths
(via sciencedaily.com) Original source Traces of sex hormones extracted from a woolly mammoth's tusk provide the first direct evidence that adult males experienced musth, a testosterone-driven episode of heightened aggression against rival males, according to a new study.
Published A novel stem cell adhesive using mussels
(via sciencedaily.com) Original source A team of researchers develops stem cell adhesive for arthritis treatment using mussel adhesion protein and hyaluronic acid.
Published 'Golden' fossils reveal origins of exceptional preservation
(via sciencedaily.com) Original source A recent study found that many of the fossils from Germany's Posidonia shale do not get their gleam from pyrite, commonly known as fool's gold, which was long thought to be the source of the shine. Instead, the golden hue is from a mix of minerals that hints at the conditions in which the fossils formed. The discovery is important for understanding how the fossils -- which are among the world's best-preserved specimens of sea life from the Early Jurassic -- came to form in the first place, and the role that oxygen in the environment had in their formation.
Published Scientists present evidence for a billion-years arms race between viruses and their hosts
(via sciencedaily.com) Original source Researchers have proposed a new evolutionary model for the origin of a kingdom of viruses called Bamfordvirae, suggesting a billion-years evolutionary arms race between two groups within this kingdom and their hosts.
Published Fossil find in California shakes up the natural history of cycad plants
(via sciencedaily.com) Original source According to researchers, a new analysis of an 80-million-year-old permineralized pollen cone found in the Campanian Holz Shale formation located in Silverado Canyon, California, offers a more accurate cycad natural history -- one where the plants diversified during the Cretaceous.
Published Do people and monkeys see colors the same way?
(via sciencedaily.com) Original source New findings in color vision research imply that humans can perceive a greater range of blue tones than monkeys do. Distinct connections found in the human retina may indicate recent evolutionary adaptations for sending enhanced color vision signals from the eye to the brain.