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Categories: Anthropology: Early Humans, Biology: Marine
Published The megalodon was less mega than previously believed



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 Sea otters helped prevent widespread California kelp forest declines over the past century



The study reveals dramatic regional kelp canopy changes along the California coast over a 100-year period. During this time there was a significant increase in kelp forest canopy along the central coast, the only region of California where southern sea otters survived after being hunted nearly to extinction for their fur in the 1800s. Contrastingly, kelp canopy decreased in northern and southern regions. At the century scale, the species' favorable impact on kelp forests along the central coast nearly compensated for the kelp losses along both northern and southern California resulting in only a slight overall decline statewide during this period.
Published New technology for conducting deep-sea research on fragile organisms



Scientists have successfully demonstrated new technologies that can obtain preserved tissue and high-resolution 3D images within minutes of encountering some of the most fragile animals in the deep ocean.
Published Pacific kelp forests are far older that we thought



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



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 Scientists uncover ocean's intricate web of microbial interactions across depths



An international team of scientists has uncovered the ocean's intricate web of microbial interactions across depths. Their research provides crucial insights into the functioning of ocean ecosystems.
Published Toxic algae blooms: Study assesses potential health hazards to humans



Water samples from 20 sites were tested using a panel of immortalized human cell lines corresponding to the liver, kidney and brain to measure cytotoxicity. Results show that each control toxin induced a consistent pattern of cytotoxicity in the panel of human cell lines assayed. Known toxins were seen only during blooms. Because cell toxicity was seen in the absence of blooms, it suggests that there might be either emergent toxins or a combination of toxins present at those times. Findings suggest that other toxins with the potential to be harmful to human health may be present in the lagoon.
Published Focus on biological processes does not capture the whole picture



The ocean plays a crucial role in the storage of carbon dioxide (CO2). The so-called marine biological carbon pump is an important research topic in this context. However a key component is often overlooked. Colleagues outline why it is insufficient to focus solely on biological processes when investigating the accumulation of CO2 in the ocean by the biological carbon pump.
Published A red knot's character is formed in first year of life



In any group of red knots, respective individuals exhibit a remarkable array of distinct character types. Birds with an exploratory character are motivated to investigate their environment and readily explore unfamiliar areas. Meanwhile, birds with inactive character types are content to remain in familiar territory. Interestingly, the birds do not appear to hatch with predetermined character types. Their characters are formed later, in the first year of life, as a result of their experiences in the Wadden Sea.
Published In hot water: Coral resilience in the face of climate change



Researchers have been studying the effects of climate change on coral reefs. Monitoring two coral species off the coast of Hawaii, one team found that local adaptations in response to near-severe heat stress allowed certain populations to endure such events.
Published Acidity of Antarctic waters could double by century's end, threatening biodiversity



Without drastically reducing global emissions, the Antarctic Ocean could become too acidic for hundreds of species living there, many already endangered by rising temperatures and sea ice loss.
Published Stranger than friction: A force initiating life



As the potter works the spinning wheel, the friction between their hands and the soft clay helps them shape it into all kinds of forms and creations. In a fascinating parallel, sea squirt oocytes (immature egg cells) harness friction within various compartments in their interior to undergo developmental changes after conception.
Published Protecting coral 'nurseries' as important as safeguarding established coral reefs



New research in the southwestern part of Hawai'i Island shows that identifying and protecting marine ecosystems both down-current and up-current of coral reefs, specifically areas where coral larvae are more likely to survive and thrive, is crucial to future coral conservation and restoration efforts -- especially as reefs face increasing pressure from the devastating effects of climate change.
Published Fastest swimming insect could inspire uncrewed boat designs



Whirligig beetles, the world's fastest-swimming insect, achieve surprising speeds by employing a strategy shared by fast-swimming marine mammals and waterfowl, according to a new study that rewrites previous explanations of the physics involved.
Published The snail or the egg?



Animals reproduce in one of two distinct ways: egg-laying or live birth. By studying an evolutionarily recent transition from egg-laying to live-bearing in a marine snail, collaborative research has shed new light on the genetic changes that allow organisms to make the switch.
Published Male southern elephant seals are picky eaters



New research suggests these large marine mammals are extremely fussy and only eat their favorite foods.
Published The choreography connecting kelp forests to the beach



A new study uncovers a symphony of synchrony between the kelp forest and beach, with broader implications for the beach food web as the climate changes.
Published Vitamin discovered in rivers may offer hope for salmon suffering from thiamine deficiency disease



Researchers have discovered vitamin B1 produced by microbes in rivers, findings that may offer hope for vitamin-deficient salmon populations.
Published 'Giant' predator worms more than half a billion years old discovered in North Greenland



Fossils of a new group of animal predators have been located in the Early Cambrian Sirius Passet fossil locality in North Greenland. These large worms may be some of the earliest carnivorous animals to have colonized the water column more than 518 million years ago, revealing a past dynasty of predators that scientists didn't know existed.
Published Fish display distinct individual behaviors when swimming to find food



Fish from the same species can evolve their sense of smell and display individual foraging 'personalities' to successfully find food in different habitats.