Showing 20 articles starting at article 421
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Categories: Biology: Zoology, Geoscience: Oceanography
Published How butterflies choose mates: Gene controls preferences
(via sciencedaily.com) Original source Tropical Heliconius butterflies are well known for the bright colour patterns on their wings. These striking colour patterns not only scare off predators -- the butterflies are poisonous and are distasteful to birds -- but are also important signals during mate selection. Evolutionary biologists have now exploited the diversity of warning patterns of various Heliconius species to investigate the genetic foundations of these preferences. In the process, the scientists identified a gene that is directly linked to evolutionary changes in a visually guided behavior.
Published Forest, stream habitats keep energy exchanges in balance, global team finds
(via sciencedaily.com) Original source Forests and streams are separate but linked ecosystems, existing side by side, with energy and nutrients crossing their porous borders and flowing back and forth between them. For example, leaves fall from trees, enter streams, decay and feed aquatic insects. Those insects emerge from the waters and are eaten by birds and bats. An international team has now found that these ecosystems appear to keep the energy exchanges in balance -- a finding that the scientists called surprising.
Published Scientists weigh up current status of blue whale populations around the world
(via sciencedaily.com) Original source The largest living animal, the blue whale (Balaenoptera musculus) which averages about 27 meters in length, has slowly recovered from whaling only to face the rising challenges of global warming, pollution, disrupted food sources, shipping, and other human threats. In a major new study, biologists have taken a stock of the number, distribution and genetic characteristics of blue whale populations around the world and found the greatest differences among the eastern Pacific, Antarctic subspecies and pygmy subspecies of the eastern Indian and western Pacific.
Published Killer whales use specialized hunting techniques to catch marine mammals in the open ocean
(via sciencedaily.com) Original source Killer whales foraging in deep submarine canyons off the coast of California represent a distinct subpopulation that uses specialized hunting techniques to catch marine mammals, researchers report.
Published Sea surface temperature research provides clear evidence of human-caused climate change
(via sciencedaily.com) Original source Claims that climate change is natural are inconsistent with new oceanic temperature trends.
Published Fish fed to farmed salmon should be part of our diet, too, study suggests
(via sciencedaily.com) Original source Scientists found that farmed salmon production leads to an overall loss of essential dietary nutrients. They say that eating more wild 'feed' species directly could benefit our health while reducing aquaculture demand for finite marine resources.
Published From the Mediterranean into the Atlantic: The Gibraltar arc is migrating to the west
(via sciencedaily.com) Original source Oceans are subject to continuous change, mostly over extremely vast periods of time running into millions of years. Researchers have now used computer simulations to demonstrate that a subduction zone originating in the Western Mediterranean will propagate into the Atlantic under the Strait of Gibraltar. According to their model, this will create a new Atlantic subduction zone 50 million years into the future, which will then move down into the Earth's mantle. The new geodynamic model explains the evolution of the Gibraltar subduction zone and its likely development, which will contribute to the renewal of the Atlantic Ocean floor.
Published There are large accumulations of plastics in the ocean, even outside so-called garbage patch
(via sciencedaily.com) Original source When plastic ends up in the ocean, it gradually weathers and disintegrates into small particles. If marine animals ingest these particles, their health can be severely affected. Large accumulations of plastic can therefore disrupt the biological balance of marine ecosystems. But which areas are particularly affected?
Published Tanks of the Triassic: New crocodile ancestor identified
(via sciencedaily.com) Original source Dinosaurs get all the glory. But aetosaurs, a heavily armored cousin of modern crocodiles, ruled the world before dinosaurs did. These tanks of the Triassic came in a variety of shapes and sizes before going extinct around 200 million years ago. Today, their fossils are found on every continent except Antarctica and Australia.
Published Scientists' discovery could reduce dependence on animals for vital anti-blood clot drug
(via sciencedaily.com) Original source Heparin, the world's most widely used blood thinner, is used during procedures ranging from kidney dialysis to open heart surgery. Currently, heparin is derived from pig intestines, but scientists have discovered how to make it in the lab. They have also developed a path to a biomanufacturing process that could potentially revolutionize how the world gets its supply of this crucial medicine.
Published Artificial streams reveal how drought shapes California's alpine ecosystems
(via sciencedaily.com) Original source Researchers have used a series of artificial stream channels to mimic the behavior of headwater creeks under future climate change scenarios. They found that drier conditions shifted the life cycles of the algae and insects that form the base of the alpine food web. However, because species adjusted to the shifts in a variety of ways, the stream ecosystems were generally resilient to the changing conditions.
Published Harnessing hydrogen at life's origin
(via sciencedaily.com) Original source A new report uncovers how hydrogen gas, the energy of the future, provided energy in the past, at the origin of life 4 billion years ago. Hydrogen gas is clean fuel. It burns with oxygen in the air to provide energy with no CO2. Hydrogen is a key to sustainable energy for the future. Though humans are just now coming to realize the benefits of hydrogen gas (H2 in chemical shorthand), microbes have known that H2 is good fuel for as long as there has been life on Earth. Hydrogen is ancient energy.
Published New discovery concerning occurrence of antibiotic resistance
(via sciencedaily.com) Original source A new study shows how heteroresistance, a transient resistance common in many bacteria, can act as a precursor to the development of antibiotic resistance.
Published Fish species that move rapidly toward the poles due to global warming decline in abundance, study finds
(via sciencedaily.com) Original source A new study has found a decline in the abundance of marine fish species that move rapidly toward the poles to escape rising sea temperatures. The researchers explain that many animal species are currently moving toward cooler regions as a result of global warming, but the velocity of such range shifts varies greatly for different species. Examining thousands of populations from almost 150 fish species, the researchers show that contrary to the prevailing view, rapid range shifts coincide with widescale population declines.
Published Scientists discover how Diadem butterfly mimics African Queen
(via sciencedaily.com) Original source Scientists have discovered how female Diadem butterflies have evolved to look like African Queen butterflies to repel predators.
Published Eyes open and toes out of water: How a giant water bug reached the island of Cyprus
(via sciencedaily.com) Original source A new visitor was reported on the coast of Cyprus, thanks to the growing power of citizen science. Researchers collected information and specimens through personal communication with amateur naturalists, but also through the internet, in order to compose the mosaic of repeated appearances of a giant water bug on the eastern shoreline of the island.
Published Global wildlife study during COVID-19 shows rural animals are more sensitive to human activity
(via sciencedaily.com) Original source One of the largest studies on wildlife activity reveals that wild animals react differently to humans depending on where the animals live and what they eat. Bigger herbivores -- plant-eating animals like deer or moose -- tend to become more active when humans are around, while meat-eaters like wolves or wolverines tend to be less active, preferring to avoid risky encounters.
Published Even inactive smokers are densely colonized by microbial communities
(via sciencedaily.com) Original source Everything is everywhere -- under certain conditions microbial communities can grow and thrive, even in places that are seemingly uninhabitable. This is the case at inactive hydrothermal vents on the sea floor. An international team is presently working to accurately quantify how much inorganic carbon can be bound in these environments.
Published Arctic nightlife: Seabird colony bursts with sound at night
(via sciencedaily.com) Original source Acoustic recordings of a colony of little auks reveal their nocturnal activities and offer valuable monitoring means for avian biology in the Arctic.
Published Shark-bitten orcas in the Northeastern Pacific could be a new population of killer whale
(via sciencedaily.com) Original source Researchers believe a group of killer whales observed hunting marine mammals including sperm whales, as well as a sea turtle, in the open ocean off California and Oregon could be a new population. Based on available evidence, the researchers posit that the 49 orcas could belong to a subpopulation of transient killer whales or a unique oceanic population found in waters off the coast of California and Oregon.