Male salmon are maturing earlier and becoming smaller, and it shows in their genes. This was the discovery of a study that examined scale samples from salmon over a 40-year period, and looked at the population genetic profile of a gene that determines salmon's age of maturity and size. The results show that the 'big salmon gene version' has become rarer in the population over time, and has been replaced by the 'small salmon gene version'.
What if we could observe genes firing off signals to cause some behaviors? We're getting closer. Researchers were able to directly match gene regulation with ritual mating behavior in fish. Their research field may also give some insight into autism spectrum disorder.
Many people see the carbon cycle as vertical -- CO2 moving up and down between soil, plants and the atmosphere. However, new Michigan State University research published in the current issue of Geophysical Research Letters, adds a dimension to the vertical perspective by showing how water moves massive amounts of carbon laterally through ecosystems -- especially during floods. These findings -- which analyzed more than 1,000 watersheds, covering about 75 percent of the contiguous US -- have implications for climate change and water quality.
When the Rhizostoma luteum jellyfish was discovered at the beginning of the 19th century in the waters of the Strait of Gibraltar, only nine specimens were identified. For years, it was so inconspicuous that later, in the 20th century, it failed to turn up for six decades. A team of scientists, with the help of a citizen initiative, has now confirmed that it is not really as difficult to find as previously believed.
Marine fishes rely on their sensory systems to survive. A study is the first to quantify the physiological effects of whole crude oil on the olfactory function of a marine vertebrate -- the Atlantic stingray. Results of the study, confirm that exposure to crude oil, at concentrations mimicking those measured in coastal areas following the Deepwater Horizon oil spill in 2010, significantly impaired olfactory function in the Atlantic stingray after just 48 hours of exposure.
The historically over-exploited Giant South American Turtle is making a significant comeback on river beaches in the Brazilian Amazon thanks to local protection efforts, say researchers at the University of East Anglia. And not only have turtle populations benefited from conservation efforts, other co-occurring species have begun to thrive once again on the protected beaches and in surrounding areas.
A new IMAS-led study has found that Antarctic krill are resilient to the increasing acidification of the ocean as it absorbs more C02 from the atmosphere due to anthropogenic carbon emissions. Krill are one of the most abundant organisms on Earth and a critical part of the Southern Ocean marine ecosystem.
This is the first known study to connect habitat with varying brain size in a single lake fish population. The finding may provide clues about how fish and other creatures will respond to mounting environmental stressors from pollution to climate change. Researchers say bigger brains contain more neurons, and more connections among them, that lend its owner cognitive and behavioural smarts that may help it adapt to new environments.
The escape response to evade perceived threats is a fundamental behavior seen throughout the animal kingdom, and laboratory studies have identified specialized neural circuits that control this behavior. To understand how these neural circuits operate in complex natural settings, researchers recorded and analyzed escape responses in wild coral reef fish. Their results show how a sequence of well-defined decision rules generates evasion behavior in a wide range of coral reef fish species.
For the first time, plastic microfibers have been discovered in wild animals' stool, from South American fur seals. The findings were made by a team of Morris Animal Foundation-funded researchers at the University of Georgia, who suggest examining scat from pinnipeds can be an efficient way to monitor environmental levels of microfibers and microplastics in the environment. Their study was published in the Marine Pollution Bulletin.