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Categories: Anthropology: Early Humans, Ecology: Sea Life
Published An awkward family reunion: Sea monsters are our cousins
(via sciencedaily.com) Original source The sea lamprey, a 500-million-year-old animal with a sharp-toothed suction cup for a mouth, is the thing of nightmares. A new study discovered that the hindbrain -- the part of the brain controlling vital functions like blood pressure and heart rate -- of both sea lampreys and humans is built using an extraordinarily similar molecular and genetic toolkit.
Published Mercury levels in tuna remain nearly unchanged since 1971
(via sciencedaily.com) Original source Tuna is one of the most popular seafoods worldwide. But this protein-rich fish can build up high levels of methylmercury from feeding on contaminated prey, like smaller fish or crustaceans. Despite efforts to reduce mercury emissions into the environment, researchers report that levels in tuna appear to be unchanged since 1971. They warn that more aggressive emission reduction targets are needed to start nudging down tuna mercury levels.
Published Toxic elements found in stranded whales, dolphins over 15 years
(via sciencedaily.com) Original source Researchers evaluated the prevalence, concentration and tissue distribution of essential and non-essential trace elements, including heavy metal toxicants in tissue (blubber, kidney, liver, skeletal muscle, skin) and fecal samples collected from 90 whales and dolphins stranded in Georgia and Florida from 2007 to 2021.
Published Baleen whales evolved a unique larynx to communicate but cannot escape human noise
(via sciencedaily.com) Original source The iconic baleen whales, such as the blue, gray and humpback whale, depend on sound for communication in the vast marine environment where they live. Now researchers have for the first time found that baleen whales evolved novel structures in their larynx to make their vast array of underwater songs.
Published Did neanderthals use glue? Researchers find evidence that sticks
(via sciencedaily.com) Original source Neanderthals created stone tools held together by a multi-component adhesive, a team of scientists has discovered. Its findings, which are the earliest evidence of a complex adhesive in Europe, suggest these predecessors to modern humans had a higher level of cognition and cultural development than previously thought.
Published Gulf corals still suffering more than a decade after Deepwater Horizon oil spill, scientists report
(via sciencedaily.com) Original source Deep-water corals in the Gulf of Mexico are still struggling to recover from the devastating Deepwater Horizon oil spill in 2010, scientists report at the Ocean Science Meeting in New Orleans. Comparing images of more than 300 corals over 13 years -- the longest time series of deep-sea corals to date -- reveals that in some areas, coral health continues to decline to this day.
Published Unlocking the energetic secrets of collective animal movement: How group behavior reduces energy costs in fish
(via sciencedaily.com) Original source Researchers questioned if coordinated group movements by animals moving through a fluid could reduce the energy cost of locomotion. By combining biomechanics and bioenergetics the researchers found not only a significant amount of energy conservation, but also identified the reduced energy use per tail beat.
Published Even very low levels of pesticide exposure can affect fish for generations
(via sciencedaily.com) Original source Fish exposed to some pesticides at extremely low concentrations for a brief period of time can demonstrate lasting behavioral changes, with the impact extending to offspring that were never exposed firsthand, a recent study found.
Published Artificial reefs help preserve coral reefs by shifting divers away from the natural ones, according to new long-term study of one in Eilat
(via sciencedaily.com) Original source Divers are essentially tourists who love coral reefs and invest a lot of time and effort to watch them. Unfortunately, divers also cause damage to corals, often unintentionally, through disturbing and resuspending sand, touching them, hitting them with their equipment, and scaring fish away. Artificial reefs have been proposed as a means of diverting diving pressure from the natural reef to alternative sites, thus preserving both dive tourism and the coral reef.
Published Nature's checkup: Surveying biodiversity with environmental DNA sequencing
(via sciencedaily.com) Original source A thousand kilometers south of Tokyo, far into the largest ocean on Earth, lies a chain of small, volcanic islands -- the Ogasawara Islands. Nature has been able to develop on its own terms here, far from both humans and the warm Kuroshio current, which acts like a shuttle, moving marine species from Taiwan, over the Ryukyu Islands, and up the Pacific coast of mainland Japan. With upwards of 70 % of trees and many animal species being endemic to the archipelago, the islands have been dubbed 'the Galapagos of the East', as they are valuable as both a biodiversity hotspot and a cradle of scientific discovery.
Published Decline in microbial genetic richness in the western Arctic Ocean
(via sciencedaily.com) Original source Researchers analyzed archival samples of bacteria and archaea populations taken from the Beaufort Sea, bordering northwest Canada and Alaska. The samples were collected between 2004 and 2012, a period that included two years -- 2007 and 2012 -- in which the sea ice coverage was historically low. The researchers looked at samples taken from three levels of water: the summer mixed layer, the upper Arctic water below it and the Pacific-origin water at the deepest level. The study examined the microbes' genetic composition using bioinformatics and statistical analysis across the nine-year time span. Using this data, the researchers were able to see how changing environmental conditions were influencing the organisms' structure and function.
Published Why two prehistoric sharks found in Ohio got new names
(via sciencedaily.com) Original source Until recently, Orthacanthus gracilis could have been considered the 'John Smith' of prehistoric shark names, given how common it was. Three different species of sharks from the late Paleozoic Era -- about 310 million years ago -- were mistakenly given that same name, causing lots of grief to paleontologists who studied and wrote about the sharks through the years and had trouble keeping them apart. But now a professor has finished the arduous task of renaming two of the three sharks -- and in the process rediscovered a wealth of fossil fishes that had been stored at a museum for years but had been largely forgotten.
Published Giant Antarctic sea spiders reproductive mystery solved
(via sciencedaily.com) Original source Instead of carrying the babies until they hatched, as in most species of sea spiders, one parent (likely the father) spent two days attaching the eggs to the rocky bottom where they developed for several months before hatching as tiny larvae.
Published Beyond peak season: Bacteria in the Arctic seabed are active all year round
(via sciencedaily.com) Original source Researchers studied the composition and function of bacteria in the seabed off Svalbard, during alternating periods of polar night and midnight sun. To do this, they specially developed a sampling device, the Ellrott grab. In contrast with bacterial communities in the overlying water, the sediment bacteria hardly change with the seasons. This is probably due to the fact that in the seabed some hard-to-digest foods are available all year round.
Published Diving deeper into our oceans: Underwater drones open new doors for global coral reef research
(via sciencedaily.com) Original source Scientists take innovation in coral e-DNA monitoring to the next level.
Published Vittrup Man crossed over from forager to farmer before being sacrificed in Denmark
(via sciencedaily.com) Original source Vittrup Man was born along the Scandinavian coast before moving to Denmark, where he was later sacrificed, according to a new study.
Published Some Pre-Roman humans were buried with dogs, horses and other animals
(via sciencedaily.com) Original source Some people from an ancient community in what is now northern Italy were interred with animals and animal parts from species such as dogs, horses and pigs. The reasons remain mysterious, but might indicate an enduring companion relationship between these humans and animals, or religious sacrificial practices, according to a new study.
Published The role of jellies as a food source in the Arctic winter
(via sciencedaily.com) Original source The Arctic is changing rapidly due to climate change. It is not only affected by increasing surface temperatures, but also by warm water from the Atlantic, which is flowing in more and more -- changing the structures and functions of the ecosystem as it also leads to species from warmer regions, such as sea jellies (also known as jellyfish) arriving in the Arctic. Using DNA metabarcoding, researchers have now been able to demonstrate that these jellyfish serve as food for amphipods on Svalbard during the polar night and thus play a greater role in Arctic food webs than previously assumed.
Published Cold-water coral traps itself on mountains in the deep sea
(via sciencedaily.com) Original source Corals searching for food in the cold and dark waters of the deep sea are building higher and higher mountains to get closer to the source of their food. But in doing so, they may find themselves trapped when the climate changes.
Published Great apes playfully tease each other
(via sciencedaily.com) Original source Babies playfully tease others as young as eight months of age. Since language is not required for this behavior, similar kinds of playful teasing might be present in non-human animals. Now cognitive biologists and primatologists have documented playful teasing in four species of great apes. Like joking behavior in humans, ape teasing is provocative, persistent, and includes elements of surprise and play. Because all four great ape species used playful teasing, it is likely that the prerequisites for humor evolved in the human lineage at least 13 million years ago.