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Categories: Anthropology: Early Humans, Biology: Marine
Published The clams that fell behind, and what they can tell us about evolution and extinction
(via sciencedaily.com) Original source A new study examined how bivalves -- the group that includes clams, mussels, scallops, and oysters -- evolved among many others in the period of rapid evolution known as the Cambrian Explosion. The team found that though many other lineages burst into action and quickly evolved a wide variety of forms and functions, the bivalves lagged behind. The study has implications for how we understand evolution and the impact of extinctions.
Published Deep sea surveys detect over five thousand new species in future mining hotspot
(via sciencedaily.com) Original source There is a massive, mineral-rich region in the Pacific Ocean -- about twice the size of India -- called the Clarion-Clipperton Zone (CCZ), which has already been divided up and assigned to companies for future deep-sea mining. To better understand what may be at risk once companies start mining, a team of biologists has built the first 'CCZ checklist' by compiling all the species records from previous research expeditions to the region. Their estimates of the species diversity of the CCZ included a total of 5,578 different species, an estimated 88% - 92% of which are entirely new to science.
Published Global macrogenetic map of marine habitat-forming species
(via sciencedaily.com) Original source Species known as marine habitat-forming species -- gorgonians, corals, algae, seaweeds, marine phanerogams, etc.-- are organisms that help generate and structure the underwater landscapes. These are natural refuges for other species, and provide biomass and complexity to the seabeds. But these key species in marine ecosystems are currently threatened by climate change and other perturbations derived from human activity. Now, a study warns that even in the marine protected areas (MPAs) the genetic diversity of structural species is not protected, although it is essential for the response and adaptation of populations to changes that alter the natural environment.
Published What you count is not necessarily what counts
(via sciencedaily.com) Original source Seawater is full of bacteria, hundreds of thousands live in every liter. But the sheer number of bacteria living in the water does not necessarily mean a lot. More important is how active they are and how quickly they duplicate.
Published Corals mark friendly algae for ingestion -- revealing possible conservation target
(via sciencedaily.com) Original source Biologists reveals how coral cells tag friendly algae before ingesting them, initiating a mutually beneficial relationship. This information could guide next-level coral conservation efforts.
Published Humanity's earliest recorded kiss occurred in Mesopotamia 4,500 years ago
(via sciencedaily.com) Original source Written sources from Mesopotamia suggest that kissing in relation to sex was practiced by the peoples of the ancient Middle East 4,500 years ago.
Published Fossil of mosasaur with bizarre 'screwdriver teeth' found in Morocco
(via sciencedaily.com) Original source Scientists have discovered a new species of mosasaur, a sea-dwelling lizard from the age of the dinosaurs, with strange, ridged teeth unlike those of any known reptile. Along with other recent finds from Africa, it suggests that mosasaurs and other marine reptiles were evolving rapidly up until 66 million years ago, when they were wiped out by an asteroid along with the dinosaurs and around 90% of all species on Earth.
Published Perfect 'pathogen' storm: Vibrio bacteria, Sargassum and plastic marine debris
(via sciencedaily.com) Original source Little is known about the ecological relationship of Vibrio bacteria with Sargassum. Evidence also is sparse as to whether vibrios colonizing plastic marine debris and Sargassum could potentially infect humans. As summer kicks off and efforts are underway to find solutions to repurpose Sargassum, could these substrates pose a triple threat to public health? Results of a study representing the first Vibrio spp. genome assembled from plastic finds Vibrio pathogens have the unique ability to 'stick' to microplastics, harboring potent opportunistic pathogens.
Published New use for A.I.: Correctly estimating fish stocks
(via sciencedaily.com) Original source A newly published artificial intelligence (AI) algorithm is allowing researchers to quickly and accurately estimate coastal fish stocks without ever entering the water.
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 Jaw shapes of 90 shark species show: Evolution driven by habitat
(via sciencedaily.com) Original source Researchers investigated how the jaw shape of sharks has changed over the course of evolution. Their conclusion: in the most widespread shark species, the jaws show relatively little variation in shape over millions of years; most variable jaws were found for deep-sea sharks.
Published Crushed clams, roaming rays: Acoustic tags reveal predator interactions
(via sciencedaily.com) Original source Inspired by clam fishermen reports, researchers used passive acoustic telemetry to gauge the interactions between two highly mobile rays. They monitored the tagged rays in the wild over two years to see how often and when they visited clam leases, designated underwater locations used to produce hard clams of all sizes from littlenecks to chowders. Results provide both good news and bad news for clammers. Rays spent even more time in these clam lease sites than clammers reported or suspected, but it's not necessarily where they prefer hanging out.
Published Researcher uses mammal DNA to zoom into the human genome with unprecedented resolution
(via sciencedaily.com) Original source Scientists have precisely identified base pairs of the human genome that remained consistent over millions of years of mammalian evolution, and which play a crucial role in human disease. The team analyzed the genomes of 240 mammals, including humans and identified base pairs that were 'constrained' -- meaning they remained generally consistent -- across mammal species over the course of evolution. The most constrained base pairs in mammals were over seven times more likely to be causal for human disease and complex trait, and over 11 times more likely when researchers looked at the most constrained base pairs in primates alone.
Published Singing humpback whales respond to wind noise, but not boats
(via sciencedaily.com) Original source A new study has found humpback whales sing louder when the wind is noisy, but don't have the same reaction to boat engines.
Published Global warming puts whales in the Southern Ocean on a diet
(via sciencedaily.com) Original source In the autumn, when right whales swim towards the coasts of South Africa, they ought to be fat and stuffed full. But in recent years, they have become thinner because their food is disappearing with the melting sea ice.
Published Like ancient mariners, ancestors of Prochlorococcus microbes rode out to sea on exoskeleton particles
(via sciencedaily.com) Original source Throughout the ocean, billions upon billions of plant-like microbes make up an invisible floating forest. As they drift, the tiny organisms use sunlight to suck up carbon dioxide from the atmosphere. Collectively, these photosynthesizing plankton, or phytoplankton, absorb almost as much CO2 as the world’s terrestrial forests. A measurable fraction of their carbon-capturing muscle comes from Prochlorococcus — an emerald-tinged free-floater that is the most abundant phytoplankton in the oceans today. New research suggests the microbe's ancient coastal ancestors colonized the ocean by rafting out on chitin particles.
Published Human ancestors preferred mosaic landscapes and high ecosystem diversity
(via sciencedaily.com) Original source A new study finds that early human species adapted to mosaic landscapes and diverse food resources, which would have increased our ancestor's resilience to past shifts in climate.
Published Hammerhead sharks hold their breath on deep water hunts to stay warm
(via sciencedaily.com) Original source Scalloped hammerhead sharks hold their breath to keep their bodies warm during deep dives into cold water where they hunt prey such as deep sea squids. This discovery provides important new insights into the physiology and ecology of a species that serves as an important link between the deep and shallow water habitats.
Published Giants of the Jurassic seas were twice the size of a killer whale
(via sciencedaily.com) Original source There have been heated debates over the size of Jurassic animals. The speculation was set to continue, but now a chance discovery in an Oxfordshire museum has led to palaeontologists publishing a paper on a Jurassic species potentially reaching a whopping 14.4 meters -- twice the size of a killer whale.
Published Nature favors creatures in largest and smallest sizes
(via sciencedaily.com) Original source Surveying the body sizes of Earth's living organisms, researchers found that the planet's biomass -- the material that makes up all living organisms -- is concentrated in organisms at either end of the size spectrum.