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Categories: Ecology: Extinction, Paleontology: General
Published Seed ferns: Plants experimented with complex leaf vein networks 201 million years ago
(via sciencedaily.com) Original source According to a research team led by palaeontologists, the net-like leaf veining typical for today's flowering plants developed much earlier than previously thought, but died out again several times. Using new methods, the fossilized plant Furcula granulifer was identified as such an early forerunner. The leaves of this seed fern species already exhibited the net-like veining in the late Triassic (around 201 million years ago).
Published Digging up new species of Australia and New Guinea's giant fossil kangaroos
(via sciencedaily.com) Original source Palaeontologists have described three unusual new species of giant fossil kangaroo from Australia and New Guinea, finding them more diverse in shape, range and hopping method than previously thought. The three new species are of the extinct genus Protemnodon, which lived from around 5 million to 40,000 years ago -- with one about double the size of the largest red kangaroo living today.
Published Tropical coral-infecting parasites discovered in cold marine ecosystems
(via sciencedaily.com) Original source Parasites thought only to infect tropical coral reefs have been discovered in a large variety of creatures in cold marine ecosystems along the Northeast Pacific, according to new research.
Published Oxidant pollutant ozone removes mating barriers between fly species
(via sciencedaily.com) Original source Researchers show that ozone levels, such as those found in many places on hot summer days today, destroy the sex pheromones of fruit fly species. As a result, some natural mating boundaries maintained by species-specific pheromones no longer exist. The research team has shown in experiments that flies of different species mate when exposed to ozone and produce hybrid offspring. Since most of these offspring are unable to reproduce, the results could provide another explanation for the global decline of insects.
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 Humans can increase biodiversity, archaeological study shows
(via sciencedaily.com) Original source Through the ages, the presence of humans has increased the heterogeneity and complexity of ecosystems and has often had a positive effect on their biodiversity.
Published Do some mysterious bones belong to gigantic ichthyosaurs?
(via sciencedaily.com) Original source Several similar large, fossilized bone fragments have been discovered in various regions across Western and Central Europe since the 19th century. The animal group to which they belonged is still the subject of much debate to this day. A study could now settle this dispute once and for all: The microstructure of the fossils indicates that they come from the lower jaw of a gigantic ichthyosaur. These animals could reach 25 to 30 meters in length, a similar size to the modern blue whale.
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 eDNA methods give a real-time look at coral reef health
(via sciencedaily.com) Original source The study underscores the crucial role of microbes in maintaining coral reef health, akin to the human gut microbiome. Hurricanes and disease outbreaks affect coral reef water microbial communities, leading to changes that may support further reef decline. Microbial analysis enables prompt assessment of disturbances' impacts on coral reefs, facilitating timely interventions to support reef ecosystems. Environmental DNA (eDNA) analysis offers a noninvasive approach to study coral microbial communities and diagnose reef health.
Published Four in five bird species cannot tolerate intense human pressures
(via sciencedaily.com) Original source In a recent study, researchers found that 78% of the world's bird species do not thrive in the most modified human-dominated environments. These species are also most likely to have declining populations.
Published Rusty-patched bumblebee's struggle for survival found in its genes
(via sciencedaily.com) Original source The rusty-patched bumblebee, once common in the United States, has declined from about 90% of its former range. Researchers conducted the first range-wide genetic study of the endangered species to inform recovery efforts.
Published Early dinosaurs grew up fast, but they weren't the only ones
(via sciencedaily.com) Original source The earliest dinosaurs had rapid growth rates, but so did many of the other animals living alongside them, according to a new study.
Published New step in tectonic squeeze that turns seafloor into mountains
(via sciencedaily.com) Original source Researchers describe zircons from the Andes mountains of Patagonia. Although the zircons formed when tectonic plates were colliding, they have a chemical signature associated with when the plates were moving apart. The researchers think that the unexpected signature could be explained by the mechanics of underlying tectonic plates that hasn't yet been described in other models.
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 Older trees help to protect an endangered species
(via sciencedaily.com) Original source The oldest trees in the forest help to prevent the disappearance of endangered species in the natural environment, according to a new study. This is the case of the wolf lichen -- threatened throughout Europe --, which now finds refuge in the oldest trees in the high mountains of the Pyrenees. This study reveals for the first time the decisive role of the oldest trees in the conservation of other living beings thanks to their characteristic and unique physiology.
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 Canada lynx historic range in US likely wider than previously thought
(via sciencedaily.com) Original source A broader past could mean a brighter future for Canada lynx in the U.S., according to recent research. The study indicates that lynx might do well in the future in parts of Utah, central Idaho and the Yellowstone National Park region, even considering climate change and the lack of lynx in those areas now. Using a model validated by historic records, researchers first found that in 1900, Canada lynx had more suitable habitat in the U.S. than the few northern corners of the country where they are found currently. The study showed the elusive big cat likely roamed over a larger area in the Pacific Northwest, Rocky Mountains, Great Lakes region and parts of New England.
Published Genomic research may help explain cancer resistance in Tasmanian devils
(via sciencedaily.com) Original source Through DNA sequencing of Tasmanian devils and their tumors, researchers have tracked the genomic interactions between the animals and the cancer.