“Scientists measure impacts of changing climate on ocean biology - Daily News and Analysis” plus 1 more

---

Scientists measure impacts of changing climate on ocean biology - Daily News and Analysis Posted: 26 Feb 2010 02:18 AM PST Message from fivefilters.org: If you can, please donate to the full-text RSS service so we can continue developing it. A three-year field program now underway is measuring carbon distributions and primary productivity in the Northwest Atlantic Ocean to help scientists worldwide determine the impacts of a changing climate on ocean biology and biogeochemistry. The study, Climate Variability on the East Coast (CliVEC), will also help validate ocean colour satellite measurements and refine biogeochemistry models of ocean processes. Researchers from NOAA, NASA and Old Dominion University are collaborating through an existing NOAA Fisheries Service field program, the Ecosystem Monitoring or EcoMon program. The EcoMon surveys are conducted six times each year by the Northeast Fisheries Science Center (NEFSC) at 120 randomly selected stations throughout the continental shelf and slope of the northeastern US, from Cape Hatteras, N.C., into Canadian waters to cover all of Georges Bank and the Gulf of Maine. This area is known as the Northeast US continental shelf Large Marine Ecosystem. The climate study team will participate in three annual EcoMon cruises aboard the 155-foot NOAA Fisheries Survey Vessel Delaware II, based at the NEFSC's laboratory in Woods Hole, Massachusetts. Findings from the climate impact project, funded by NASA, will help scientists better understand how annual and decadal-scale climate variability affects the growth of phytoplankton, which is the basis of the oceanic food chain. The project will also examine organic carbon distributions along the continental margin of the East Coast and collect data for ocean acidification studies. According to laboratory colleague Jon Hare, an oceanographer and plankton specialist, "The CliVEC program will provide a more complete understanding of the northeast US shelf ecosystem." "It extends our EcoMon survey efforts, and we are excited about the new knowledge and advances in satellite models that we will all gain from this collaboration and pooling of resources," he said. The team of scientists from GSFC and ODU is conducting water sampling and experiments to quantify primary productivity and carbon distributions. "Phytoplankton are the foundation of the food chain in the ocean and produce about half of the oxygen on Earth," said Antonio Mannino from NASA's Goddard Space Flight Center (GSFC). "By understanding the distribution of phytoplankton populations and how they react to natural and anthropogenic forcing, we can better predict future responses of phytoplankton and possibly even fisheries," he added. Five Filters featured article: Chilcot Inquiry. Available tools: PDF Newspaper, Full Text RSS, Term Extraction.

Promiscuous females can help save the human race - Daily News and Analysis Posted: 25 Feb 2010 10:29 PM PST Message from fivefilters.org: If you can, please donate to the full-text RSS service so we can continue developing it. WASHINGTON: Women who sleep around could stop humans from becoming extinct, that's the conclusion of a new study. The new research by the Universities of Exeter and Liverpool has been published in Current Biology. The study could solve the mystery of why females of most species have multiple mates, despite this being more risky for the individual. Known as 'polyandry' among scientists, the phenomenon of females having multiple mates is shared across most animal species, from insects to mammals. This study suggests that polyandry reduces the risk of populations becoming extinct because of all-female broods being born. This can sometimes occur as a result of a sex-ratio distortion (SR) chromosome, which results in all of the Y chromosome 'male' sperm being killed before fertilisation. The all-female offspring will carry the SR chromosome, which will be passed on to their sons in turn resulting in more all-female broods. Eventually there will be no males and the population will die out. To reach the conclusion, the scientists worked with the fruitfly Drosophila pseudoobscura. They gave some populations the opportunity to mate naturally, meaning that the females had multiple partners. The others were restricted to having one mate each. They bred several generations of these populations, so they could see how each fared over time. Over fifteen generations, five of the twelve populations that had been monogamous became extinct as a result of males dying out. The SR chromosome was far less prevalent in the populations in which females had the opportunity to have multiple mates and none of these populations became extinct. The study shows how having multiple mates can suppress the spread of the SR chromosome, making all-female broods a rarity. This is because males that carry the SR chromosome produce only half as many sperm as normal males. When a female mates with multiple males, their sperm will compete to fertilise her eggs. The few sperm produced by males carrying the SR chromosome are out-competed by the sperm from normal males, and the SR chromosome cannot spread. Lead author Professor Nina Wedell of the University of Exeter said: "We were surprised by how quickly - within nine generations - a population could die out as a result of females only mating with one partner. Polyandry is such a widespread phenomenon in nature but it remains something of an enigma for scientists. This study is the first to suggest that it could actually save a population from extinction." Five Filters featured article: Chilcot Inquiry. Available tools: PDF Newspaper, Full Text RSS, Term Extraction.

You are subscribed to email updates from Biology - Bing News To stop receiving these emails, you may unsubscribe now.	Email delivery powered by Google
Google Inc., 20 West Kinzie, Chicago IL USA 60610