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Categories: Biology: Evolutionary, Biology: Zoology
Published Rays were more diverse 150 million years ago than previously thought
(via sciencedaily.com) Original source Scientists have explored the puzzling world of rays that lived 150 million years ago and discovered a previously hidden diversity -- including a new ray species. This study significantly expands the understanding of these ancient cartilaginous fish and provides further insights into a past marine ecosystem.
Published Rose essential oil: A safe pesticide for organic agriculture
(via sciencedaily.com) Original source Following injury, plants release terpenoids to enhance their defenses. Researchers studying terpenoid-enriched essential oils (EOs) have found that rose EO (REO) can stimulate defense genes in tomato leaves. Furthermore, REO attracts herbivores that protect the plant from the moth species, Spodoptera litura, and Tetranychus urticae, a mite pest. This suggests that applying REO could be a sustainable approach to pest management in organic farming.
Published Researchers name prehistoric amphibian ancestor discovered in Smithsonian collection after Kermit the Frog
(via sciencedaily.com) Original source Scientists have uncovered the fossilized skull of a 270-million-year-old ancient amphibian ancestor in the collection of the Smithsonian's National Museum of Natural History. The team of researchers described the fossil as a new species of proto-amphibian, which they named Kermitops gratus in honor of the iconic Muppet, Kermit the Frog.
Published Entanglements of humpback whales in fish farms rare -- and naivety could be to blame
(via sciencedaily.com) Original source The first study of humpback whale entanglements in B.C. aquaculture facilities found eight over 13 years, with the curiosity of young whales a potential contributing factor.
Published Species diversity promotes ecosystem stability
(via sciencedaily.com) Original source What maintains stability within an ecosystem and prevents a single best competitor from displacing other species from a community? Does ecosystem stability depend upon the presence of a wide variety of species, as early ecologists believed, or does diversity do the exact opposite, and lead to instability, as modern theory predicts? A new study suggests an answer to this question that has been a subject of debate among ecologists for half a century.
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 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 Decoding the Easter Bunny -- an eastern Finnish brown hare to represent the standard for the species' genome
(via sciencedaily.com) Original source Biologists have published a chromosomally assembled reference genome for the European brown hare. The genome consists of 2.9 billion base pairs, which form 23 autosomal chromosomes, and X and Y sex chromosomes. The timing of the genome release is very appropriate as the brown hare also represents the original Easter Bunny familiar from European folklore.
Published Across oceans and millennia: decoding the origin and history of the bottle gourd
(via sciencedaily.com) Original source Researchers have uncovered intriguing details about the origins and spread of the bottle gourd, one of the oldest domesticated crops. Their work unveils the genetic diversification and population history of this hard-shelled plant that was used to make bottles, instruments, and containers for over 10,000 years by ancient civilizations.
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 Genes identified that allow bacteria to thrive despite toxic heavy metal in soil
(via sciencedaily.com) Original source Some soil bacteria can acquire sets of genes that enable them to pump the heavy metal nickel out of their systems, a study has found. This enables the bacteria to not only thrive in otherwise toxic soils but help plants grow there as well. A research team pinpointed a set of genes in wild soil bacteria that allows them to do this in serpentine soils which have naturally high concentrations of toxic nickel. The genetic discovery could help inform future bioremediation efforts that seek to return plants to polluted soils.
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 Industrial societies losing healthy gut microbes
(via sciencedaily.com) Original source Our eating habits in industrialized societies are far removed from those of ancient humans. This is impacting our intestinal flora, it seems, as newly discovered cellulose degrading bacteria are being lost from the human gut microbiome, especially in industrial societies.
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 Genetic basis for the evolution of hair discovered in the clawed frog
(via sciencedaily.com) Original source The development of hair was of central importance for the evolution of mammals and thus also of humans. However, the evolutionary origin of the genetic program of hair was previously unknown. Researchers have now been able to show that important hair components and their genetic control have already evolved in amphibians. Human hair therefore shows unexpected similarities to the claws of clawed frogs.
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.