Science Shots: Micro-Foodwebs, Shrinking Brains, and More

Fight disinformation: Sign up for the free Mother Jones Daily newsletter and follow the news that matters.

An idiosyncratic sampling of the latest science papers. Forthwith: The tiny foodwebs between ants, plants, and fungi; How smoking shrinks brains; How conservation saved 20 percent of threatened vertebrate species. Plus a bonus image from space of this week’s monster extratropical storm.

  • German reasearchers have found that a specific region of the cerebral cortex of active smokers is thinner than in lifelong nonsmokers. They used brain MRI images to measure the thickness of the orbitofrontal cortex in both groups and found signigicant thinning in smokers, the exact amount related to their daily cigarette consumption and to the duration of their smoking habit. They’ll be conducting further research on the brains of ex-smokers. The human orbitofrontal cortex is poorly understood, but seems to be involved in decision-making and expectation associated with reward and punishment. The paper: S. Kühn, F. Schubert, J. Gallinat. Reduced thickness in medial orbitofrontal cortex in smokers. Biological Psychiatry. DOI:10.1016/j.biopsych.2010.08.004.

Approximate location of the OFC shown on a sagittal MRI. Image courtesy Wikimedia Commons.Approximate location of the OFC shown on a sagittal MRI. Image courtesy Wikimedia Commons.

  • A new paper in Science finds that 20 percent of vertebrates reviewed on the IUCN Red List are now considered threatened or worse, and that an average of 52 species of mammals, birds, and amphibians move one category closer to extinction each year. Lead author Michael Hoffman says the alarming findings should not obscure the benefits of conservation action, without which, species losses would now be 20 percent higher. “Nonetheless,” write the authors, “current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, over-exploitation, and invasive alien species.” The paper: M. Hoffmann, et al. The Impact of Conservation on the Status of the World’s Vertebrates. Science. DOI: 10.1126/science.1194442.

American Bison skull heap. There were as few as 750 bison in 1890 from economic-driven overhunting. Image courtesy Wikimedia Commons.American Bison skull heap. There were as few as 750 bison in 1890, the survivors of overhunting. Image courtesy Wikimedia Commons.

  • Some plants provide symbiotic ants with food and a specialized nesting cavity, known as a domatium. In many of these  ant–plant symbioses a fungal patch also grows within each domatium. Experimental research from France and Cameroon shows just how deeply involved the three species (plant, ant, fungus) really are. The researchers provided carbon and nitrogen to the arborial African ants and tracked the nutrient distribution between plant, ant, and fungus over the course of nearly two years, uncovering a surprisingly complex micro-foodweb. From the abstract:

The symbiotic nature of the fungal association has been shown in the ant-plant Leonardoxa africana and its protective mutualist ant Petalomyrmex phylax. To decipher trophic fluxes among the three partners, food enriched in 13C and 15N was given to the ants and tracked in the different parts of the symbiosis up to 660 days later. The plant received a small, but significant, amount of nitrogen from the ants. However, the ants fed more intensively the fungus. The pattern of isotope enrichment in the system indicated an ant behaviour that functions specifically to feed the fungus. After 660 days, the introduced nitrogen was still present in the system and homogeneously distributed among ant, plant and fungal compartments, indicating efficient recycling within the symbiosis. Another experiment showed that the plant surface absorbed nutrients (in the form of simple molecules) whether or not it is coated by fungus. Our study provides arguments for a mutualistic status of the fungal associate and a framework for investigating the previously unsuspected complexity of food webs in ant–plant mutualisms.

Head view of ant Petalomyrmex phylax. Credit: AntWeb.org, courtesy Wikimedia Commons.Head view of ant Petalomyrmex phylax. Credit: AntWeb.org, courtesy Wikimedia Commons.

  • The monster storm that fouled many a travel plan this week (including mine), possessed unusually strong winds, rain, hail, and widespread tornadoes. It set a record for the lowest pressure not associated with a hurricane measured over land in the continental US. At 5:13 p.m. CDT, the weather station in Bigfork, Minnesota recorded 955.2 millibars (28.21 inches of pressure)a low pressure corresponding to a Category 3 hurricane. Thanks to the Earth Observatory.

Strong extratropical cyclone over the US Midwest, 26-27 October 2010. NASA Earth Observatory imagery created by Jesse Allen, imagery provided courtesy of the NASA GOES Project Science Office.Strong extratropical cyclone over the US Midwest, 26-27 October 2010. NASA Earth Observatory imagery created by Jesse Allen, imagery provided courtesy of the NASA GOES Project Science Office.

WE'LL BE BLUNT

It is astonishingly hard keeping a newsroom afloat these days, and we need to raise $253,000 in online donations quickly, by October 7.

The short of it: Last year, we had to cut $1 million from our budget so we could have any chance of breaking even by the time our fiscal year ended in June. And despite a huge rally from so many of you leading up to the deadline, we still came up a bit short on the whole. We can’t let that happen again. We have no wiggle room to begin with, and now we have a hole to dig out of.

Readers also told us to just give it to you straight when we need to ask for your support, and seeing how matter-of-factly explaining our inner workings, our challenges and finances, can bring more of you in has been a real silver lining. So our online membership lead, Brian, lays it all out for you in his personal, insider account (that literally puts his skin in the game!) of how urgent things are right now.

The upshot: Being able to rally $253,000 in donations over these next few weeks is vitally important simply because it is the number that keeps us right on track, helping make sure we don't end up with a bigger gap than can be filled again, helping us avoid any significant (and knowable) cash-flow crunches for now. We used to be more nonchalant about coming up short this time of year, thinking we can make it by the time June rolls around. Not anymore.

Because the in-depth journalism on underreported beats and unique perspectives on the daily news you turn to Mother Jones for is only possible because readers fund us. Corporations and powerful people with deep pockets will never sustain the type of journalism we exist to do. The only investors who won’t let independent, investigative journalism down are the people who actually care about its future—you.

And we need readers to show up for us big time—again.

Getting just 10 percent of the people who care enough about our work to be reading this blurb to part with a few bucks would be utterly transformative for us, and that's very much what we need to keep charging hard in this financially uncertain, high-stakes year.

If you can right now, please support the journalism you get from Mother Jones with a donation at whatever amount works for you. And please do it now, before you move on to whatever you're about to do next and think maybe you'll get to it later, because every gift matters and we really need to see a strong response if we're going to raise the $253,000 we need in less than three weeks.

payment methods

WE'LL BE BLUNT

It is astonishingly hard keeping a newsroom afloat these days, and we need to raise $253,000 in online donations quickly, by October 7.

The short of it: Last year, we had to cut $1 million from our budget so we could have any chance of breaking even by the time our fiscal year ended in June. And despite a huge rally from so many of you leading up to the deadline, we still came up a bit short on the whole. We can’t let that happen again. We have no wiggle room to begin with, and now we have a hole to dig out of.

Readers also told us to just give it to you straight when we need to ask for your support, and seeing how matter-of-factly explaining our inner workings, our challenges and finances, can bring more of you in has been a real silver lining. So our online membership lead, Brian, lays it all out for you in his personal, insider account (that literally puts his skin in the game!) of how urgent things are right now.

The upshot: Being able to rally $253,000 in donations over these next few weeks is vitally important simply because it is the number that keeps us right on track, helping make sure we don't end up with a bigger gap than can be filled again, helping us avoid any significant (and knowable) cash-flow crunches for now. We used to be more nonchalant about coming up short this time of year, thinking we can make it by the time June rolls around. Not anymore.

Because the in-depth journalism on underreported beats and unique perspectives on the daily news you turn to Mother Jones for is only possible because readers fund us. Corporations and powerful people with deep pockets will never sustain the type of journalism we exist to do. The only investors who won’t let independent, investigative journalism down are the people who actually care about its future—you.

And we need readers to show up for us big time—again.

Getting just 10 percent of the people who care enough about our work to be reading this blurb to part with a few bucks would be utterly transformative for us, and that's very much what we need to keep charging hard in this financially uncertain, high-stakes year.

If you can right now, please support the journalism you get from Mother Jones with a donation at whatever amount works for you. And please do it now, before you move on to whatever you're about to do next and think maybe you'll get to it later, because every gift matters and we really need to see a strong response if we're going to raise the $253,000 we need in less than three weeks.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate