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Categories: Ecology: Invasive Species, Paleontology: Fossils
Published DNA from preserved feces reveals ancient Japanese gut environment
(via sciencedaily.com) Original source DNA from ancient feces can offer archaeologists new clues about the life and health of Japanese people who lived thousands of years ago, according to a new study.
Published Sparrows uniquely adapted to Bay Area marshes are losing their uniqueness
(via sciencedaily.com) Original source How does loss of habitat affect the animals still living there? A genetic study of saltwater-adapted Savannah sparrows around the San Francisco Bay Area shows that the 90% loss of tidal marsh habitat has led to more interbreeding with freshwater-adapted Savannah sparrows, diminishing their genetic adaptation to saltwater, such as enlarged kidneys and larger beak. This could lessen their ability to live in a saltwater habitat.
Published Ancient brown bear genomes sheds light on Ice Age losses and survival
(via sciencedaily.com) Original source The brown bear is one of the largest living terrestrial carnivores, and is widely distributed across the Northern Hemisphere. Unlike many other large carnivores that went extinct at the end of the last Ice Age (cave bear, sabretoothed cats, cave hyena), the brown bear is one of the lucky survivors that made it through to the present. The question has puzzled biologists for close to a century -- how was this so?
Published New pieces in the puzzle of first life on Earth
(via sciencedaily.com) Original source Microorganisms were the first forms of life on our planet. The clues are written in 3.5 billion-year-old rocks by geochemical and morphological traces, such as chemical compounds or structures that these organisms left behind. However, it is still not clear when and where life originated on Earth and when a diversity of species developed in these early microbial communities. Evidence is scarce and often disputed. Now, researchers have uncovered key findings about the earliest forms of life. In rock samples from South Africa, they found evidence dating to around 3.42 billion years ago of an unprecedentedly diverse carbon cycle involving various microorganisms. This research shows that complex microbial communities already existed in the ecosystems during the Palaeoarchaean period.
Published Study offers rare long-term analysis of techniques for creating standing dead trees for wildlife habitat
(via sciencedaily.com) Original source Ecologists have long known that standing dead trees, commonly referred to as snags, are an important habitat element for forest dwellers and act as a driver of biodiversity. They're so important that in some managed forests, snag creation is part of the conservation tool kit -- i.e., crews sometimes convert a percentage of live trees into dead ones through techniques ranging from sawing off their tops to wounding their trunks to injecting them with disease-causing fungi.
Published A new perspective on the temperature inside tropical forests
(via sciencedaily.com) Original source New worldwide maps of temperatures inside tropical forests show that global warming affect different way in different parts of the forests. Undergrowth level temperature of the tropical forests can be even 4 degrees less than average temperature of the area.
Published Complex green organisms emerged a billion years ago
(via sciencedaily.com) Original source Of all the organisms that photosynthesize, land plants have the most complex form. How did this morphology emerge? A team of scientists has taken a deep dive into the evolutionary history of morphological complexity in streptophytes, which include land plants and many green algae. Their research allowed them to go back in time to investigate lineages that emerged long before land plants existed.
Published Student discovers 200-million-year-old flying reptile
(via sciencedaily.com) Original source Gliding winged-reptiles were amongst the ancient crocodile residents of the Mendip Hills in Somerset, England, researchers at the have revealed.
Published The megalodon was less mega than previously believed
(via sciencedaily.com) Original source A new study shows the Megalodon, a gigantic shark that went extinct 3.6 million years ago, was more slender than earlier studies suggested. This finding changes scientists' understanding of Megalodon behavior, ancient ocean life, and why the sharks went extinct.
Published Why animals shrink over time explained with new evolution theory
(via sciencedaily.com) Original source The new theoretical research proposes that animal size over time depends on two key ecological factors.
Published Woolly mammoth movements tied to earliest Alaska hunting camps
(via sciencedaily.com) Original source Researchers have linked the travels of a 14,000-year-old woolly mammoth with the oldest known human settlements in Alaska, providing clues about the relationship between the iconic species and some of the earliest people to travel across the Bering Land Bridge. Isotopic data, along with DNA from other mammoths at the site and archaeological evidence, indicates that early Alaskans likely structured their settlements to overlap with areas where mammoths congregated. Those findings, highlighted in the new issue of the journal Science Advances, provide evidence that mammoths and early hunter-gatherers shared habitat in the region. The long-term predictable presence of woolly mammoths would have attracted humans to the area.
Published Pacific kelp forests are far older that we thought
(via sciencedaily.com) Original source Fossils of kelp along the Pacific Coast are rare. Until now, the oldest fossil dated from 14 million years ago, leading to the view that today's denizens of the kelp forest -- marine mammals, urchins, sea birds -- coevolved with kelp. A recent amateur discovery pushes back the origin of kelp to 32 million years ago, long before these creatures appeared. A new analysis suggests the first kelp grazers were extinct, hippo-like animals called desmostylians.
Published Key moment in the evolution of life on Earth captured in fossils
(via sciencedaily.com) Original source New research has precisely dated some of the oldest fossils of complex multicellular life in the world, helping to track a pivotal moment in the history of Earth when the seas began teeming with new lifeforms -- after four billion years of containing only single-celled microbes.
Published Human activity facilitates invasive plants' colonization in Mediterranean ecosystems
(via sciencedaily.com) Original source Some invasive plants can form persistent banks of seeds that remain under the soil for years, and this makes their eradication practically impossible. Over time, this invisible population of large quantities of living, buried plants -- in seed form -- will reoccupy ecosystems and displace the typical flora of the natural environment.
Published Even the oldest eukaryote fossils show dazzling diversity and complexity
(via sciencedaily.com) Original source The sun has just set on a quiet mudflat in Australia's Northern Territory; it'll set again in another 19 hours. A young moon looms large over the desolate landscape. No animals scurry in the waning light. No leaves rustle in the breeze. No lichens encrust the exposed rock. The only hint of life is some scum in a few puddles and ponds. And among it lives a diverse microbial community of our ancient ancestors.
Published Oldest known fossilized skin is 21 million years older than previous examples
(via sciencedaily.com) Original source Researchers have identified a 3D fragment of fossilized skin that is at least 21 million years than previously described skin fossils. The skin, which belonged to an early species of Paleozoic reptile, has a pebbled surface and most closely resembles crocodile skin. It's the oldest example of preserved epidermis, the outermost layer of skin in terrestrial reptiles, birds, and mammals, which was an important evolutionary adaptation in the transition to life on land.
Published Prehistoric person with Turner syndrome identified from ancient DNA
(via sciencedaily.com) Original source Researchers have developed a new technique to measure the number of chromosomes in ancient genomes more precisely, using it to identify the first prehistoric person with mosaic Turner syndrome (characterized by one X chromosome instead of two [XX]), who lived about 2500 years ago.
Published New research sheds light on an old fossil solving an evolutionary mystery
(via sciencedaily.com) Original source Picrodontids -- an extinct family of placental mammals that lived several million years after the extinction of the dinosaurs -- are not primates as previously believed.
Published The extinction of the giant ape: Long-standing mystery solved
(via sciencedaily.com) Original source The largest ever primate Gigantopithecus blacki went extinct when other Asian great apes were thriving, and its demise has long been a mystery. A massive regional study of 22 caves in southern China explores a species on the brink of extinction between 295,000 and 215,000 years ago. As the environment became more seasonal, forest plant communities changed Primates such as orangutans adapted their eating habits and behaviors in response but G. blacki showed signs of stress, struggled to adapt and their numbers dwindled.
Published Scientists name the most common tropical tree species
(via sciencedaily.com) Original source Researchers have found almost identical patterns of tree diversity across the world's tropical forests. The study of over one million trees across 1,568 locations found that just 2.2% of tree species make up 50% of the total number of trees in tropical forests across Africa, the Amazon, and Southeast Asia. Each continent consists of the same proportion of a few common species and many rare species.