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	<title>The Scribbling Paleontologist</title>
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		<title>2nd Annual UC Riverside Climate Change Fair to Take Place on Oct. 13</title>
		<link>http://scribblingpaleo.com/?p=143</link>
		<comments>http://scribblingpaleo.com/?p=143#comments</comments>
		<pubDate>Sat, 13 Oct 2012 07:10:04 +0000</pubDate>
		<dc:creator>Lucas</dc:creator>
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		<description><![CDATA[A press release I wrote for a climate science fair hosted by UC Riverside in October, 2012 Last year, over 600 people, from kindergarteners to adults, came to the University of California, Riverside for the first-ever Refresh Riverside! A Community &#8230; <a href="http://scribblingpaleo.com/?p=143">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
			<content:encoded><![CDATA[<p><em>A <a href="http://ucrtoday.ucr.edu/9251">press release</a> I wrote for a climate science fair hosted by UC Riverside in October, 2012</em></p>
<p>Last year, over 600 people, from kindergarteners to adults, came to the University of California, Riverside for the first-ever <em>Refresh Riverside! A Community and Sustainability Fair</em>&#8211;a fair where they got to learn the science behind one of the most discussed issues of our time: climate change.</p>
<p>The free popular fair is back this year, with some new twists and additions. The fair will take place on Oct. 13 from 10 a.m.–3 p.m. near UC Riverside’s bell tower, and will have it all: from informational booths to engaging games and free food.</p>
<p>Fairgoers will have the chance to learn about and calculate their carbon footprint. They can head next to the “Carbon Price is Right” game to learn about the eco-friendliness of everyday activities (e.g., driving a car versus riding a bike).</p>
<p>Closer to home, the “Future of the Inland Empire” booth will present scenarios for how climate change might affect Riverside County in the near and far future. In “Water Conservation,” attendees will learn about just how limited water resources are (particularly in the Inland Empire), and how saving even a little water every day can make a big difference.</p>
<p>Last year’s popular “Sea Level Limbo” game will also be at the fair, along with “Climate Change Jeopardy!,” which will test fairgoers’ climate-related knowledge in a &#8220;Jeopardy!” format.</p>
<p>Climate experts from NASA and UCR will be on hand to answer questions about climate change, such as how climate change is affecting us, and what the future consequences–both short term and long term–of climate change are likely to be.</p>
<p>A new addition to this year’s fair is the “I Pledge to Refresh Riverside” banner. Attendees can pledge on this banner to make a change in their everyday lives to be more environmentally sustainable, such as using reusable grocery bags and carpooling to work.</p>
<p>“We want to communicate to everybody–children and their parents–that we can each be working to reduce our impact on the environment and adapt to climate change,” said Mary Droser, a professor in the Department of Earth Sciences who is directing the fair for a second year in a row. “This year’s fair is about taking the information you learn about climate change and applying it to your life.”</p>
<p>UCR is a leader in sustainability education and research, focusing on topics such as the environment, energy, climate, recycling, waste management, transportation, and water.</p>
<p>“Because higher education provides the intellect and initiative to move this country forward, it is important that we set the standard for society to aspire to and train the intellectual community and the workforce to preserve this planet for future generations … and do battle with the causes of climate change,” said UCR Chancellor Timothy P. White.</p>
<div id="attachment_144" class="wp-caption alignleft" style="width: 2573px"><a href="http://scribblingpaleo.com/wp-content/uploads/2012/10/Chancellor1.jpg"><img class=" wp-image-144 " title="Chancellor" src="http://scribblingpaleo.com/wp-content/uploads/2012/10/Chancellor1.jpg" alt="" width="2563" height="1709" /></a><p class="wp-caption-text">UC Riverside Chancellor Timothy P. White signs the &#8220;I pledge to Refresh Riverside&#8221; banner that will be draped around the university&#8217;s bell tower on October 13</p></div>
<p>Free food–including food from Rubio’s Fresh Mexican Grill, snow cones and cotton candy–will be available. Reservations are not needed to attend the fair. Parking in Lot 1, at the corner of University Avenue and West Campus Drive, is free.</p>
<p>For a complete list of booths, activities, sponsors and extra information, please visit: <a href="http://globalclimate.ucr.edu/refresh2012.html">http://globalclimate.ucr.edu/refresh2012.html</a>.</p>
<p>The community climate fair is being hosted by <a href="http://newsroom.ucr.edu/2492">NASA</a>; UCR’s <a href="http://chancellor.ucr.edu/">Office of the Chancellor</a>, the <a href="http://cnas.ucr.edu/">College of Natural and Agricultural Sciences</a>, and the Department of Earth Sciences; the <a href="http://www.rusdlink.org/site/default.aspx?PageID=1">Riverside Unified School District</a>; and the Moscarello Family Foundation.</p>
<p><strong>Q&amp;A with Mary Droser:</strong></p>
<p><em>Why should the public be concerned about climate change?</em></p>
<p>Climate change is one of the biggest issues facing society today. While it often seems like a strictly academic issue, the fact is that climate change will affect all of us. Many people think that a 1 degree change in temperature isn’t that big a deal, but the effects of climate change in the form of global warming — from sea level rise to more extreme weather events — will affect our way of life and our economy. Most climate scientists agree that climate change is happening, and so, as a society, we need to take action.</p>
<p><em>Why is the fair happening again this year?</em></p>
<p>We have many more things to talk to the public about at this year’s fair. We have several new activities, booths, and sponsors, and we’re implementing a new theme: sustainability. Here sustainability means the power of one person or one family to help curb climate change by pledging to change some everyday practices — for instance, turning off lights in vacant rooms in the house. We really want fairgoers to learn that they can, in fact, make a difference.</p>
<p><em>What message do you want fairgoers to take home with them?</em></p>
<p>We hope that everybody who comes to the fair understands a few more things about climate change — the basic scientific facts, and what they can do to live more sustainably. If people walk away knowing that we are facing climate change as a country and as a globe, and that they can do something to contribute to the solution, then the fair has done its job.</p>
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		<title>Exotic beetle brings tree-killing fungus to Southern California</title>
		<link>http://scribblingpaleo.com/?p=108</link>
		<comments>http://scribblingpaleo.com/?p=108#comments</comments>
		<pubDate>Sat, 29 Sep 2012 03:49:05 +0000</pubDate>
		<dc:creator>Lucas</dc:creator>
				<category><![CDATA[Uncategorized]]></category>

		<guid isPermaLink="false">http://scribblingpaleo.com/?p=108</guid>
		<description><![CDATA[An article I wrote, published in this month&#8217;s edition of &#8220;Advisor,&#8221; the magazine of the California Association of Pest Control Advisors. A low, narrow bench first catches your eye in the office of plant pathologist Akif Eskalen at the University &#8230; <a href="http://scribblingpaleo.com/?p=108">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
			<content:encoded><![CDATA[<p><em>An article I wrote, published in this month&#8217;s edition of &#8220;Advisor,&#8221; the magazine of the California Association of Pest Control Advisors.</em></p>
<p>A low, narrow bench first catches your eye in the office of plant pathologist Akif Eskalen at the University of California, Riverside. Carved from a tree, the bench looks marbleized: a snapshot of black and cream colors swirling around each other.</p>
<p>“The black swirls are diseased areas called canker,” Eskalen says as he leans back in his chair, looking relaxed. “While the cankerous sections are part of what killed the tree, they can make beautiful, artistic displays.”</p>
<p>Eskalen, who studies plant diseases, received the bench as a gift from a California county farm advisor. Often, Eskalen consults with farm advisors to keep track of and investigate plant diseases affecting commercial crops.</p>
<p>But in February this year, a chance e-mail came in: a Los Angeles woman had found dark splotches lined with a white powdery substance, or exudate, on her backyard avocado tree, and wanted an expert opinion.</p>
<p>“I usually wouldn’t make a trip out to see just one tree,” says Eskalen. “But when I saw photos of the splotches, I was in that backyard within two hours.”</p>
<p>When he was before the tree, Eskalen noticed not one, but two similar-looking splotches, the kind of repetition that ruled out the possibility of an isolated, mechanical disturbance. Eskalen then sampled the afflicted areas for molecular analysis. Using emergency research funds provided by the California Avocado Commission, the culprit was revealed in his lab to be a new species of the fungus <em>Fusarium</em>, which causes the disease “Fusarium dieback.”</p>
<p>Symptoms in avocado include the appearance of white powdery <a href="http://en.wikipedia.org/wiki/Exudate">exudate</a> in association with a single beetle exit hole on the bark of the trunk and main branches of the tree.  This exudate could be dry or it can appear as a wet discoloration.</p>
<p>“This is the very same fungus that caused avocado dieback in Israel,” Eskalen said. “The California Avocado Commission is concerned about the economic damage this fungus can do to the industry here in California.”</p>
<p>Reconnaissance revealed that the fungus has already spread beyond Los Angeles County, causing branch dieback and affecting the overall health of avocado and landscape trees in areas of Orange County.</p>
<p>But how did the fungus get to Southern California?</p>
<p>“Associated with dieback-afflicted trees are small holes, less than 1 millimeter wide, made by a new species of beetle related to the Tea Shot Hole Borer or <em>Euwallacea fornicatus</em>, a South Asian ambrosia beetle smaller than a grain of rice,” says Eskalen.</p>
<p>This new beetle, which carries the <em>Fusarium </em>fungus in its mouthparts, has twiggy legs sticking out beneath it, and is covered with environment-sensing spindles. As compact as it is small, the animal’s head looks like it was shoved under its forward, dark brown hull.</p>
<p>“We live in such a small world now that it’s not very hard to imagine how the beetle may have traveled from Israel or Asia to California,” Eslalen explains. “It was only a matter of time before something like this hit us.”</p>
<p>More than just a carrier, the beetle has a symbiotic relationship with the fungus. When the beetle bores into the tree to lay its eggs, it inoculates the tree with the fungus, which consumes and, in the process, clogs and destroys the tree’s xylem, or circulatory tissues. When the beetle eggs hatch, the larvae feed off the already-thriving fungus.</p>
<p>The results can be devastating. The fungus kills the vascular tissue of the tree, which, in turn, disturbs water and nutrient circulation. Dead tissue areas can then grow in size and number until dieback kills the entire tree.</p>
<p>Because the fungus is not dependent on a specific species of tree to survive, dieback affects a number of tree types, including tea, citrus, guava, lychee, mango, persimmon, pomegranate, macadamia, and silk oak. According to Eskalen, the worst-affected tree is the box elder, a common landscape tree.</p>
<p>Since this is a new disease, it is unclear what the long-term impacts are, or what control methods should be implemented.</p>
<p>Richard Stouthamer, a professor of entomology at UC Riverside, is collaborating with Eskalen on the <em>Fusarium</em> problem.  He says anything from insecticides to biological control methods might be used to control the fungus’ spread.</p>
<p>“While insecticides can be effective, they may be difficult to administer,” says Stouthamer, who, along with his PhD student Paul Rugman-Jones, identified the new beetle. “This is because once the beetles bore into a tree they are very well-protected from outside disturbance. If the beetle makes the jump to urban trees, then using insecticides would, obviously, be out of the question.”</p>
<p>Biological control would entail introducing an insect species that would eliminate the beetle, either through predation or parasitism. Biological control was applied last year by UCR scientists when a natural predator of the psyllid–another Southern California pest that spreads disease to citrus crops–was released into the wild.</p>
<p>Having already spread throughout much of Southern California, Eskalen and his colleagues are racing to assess and contain the fungus-carrying beetle before it makes its way into–and devastates–commercial avocado crops.</p>
<p>“We are asking gardeners to keep an eye on their trees and report to us any sign of the fungus or beetle,” Eskalen says.</p>
<p>Members of the public can report sightings of the Tea Shot Hole Borer and signs of Fusarium dieback by calling (951) 827-3499 or emailing <a href="mailto:aeskalen@ucr.edu">aeskalen@ucr.edu</a>.</p>
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		<title>The Marathon Professor</title>
		<link>http://scribblingpaleo.com/?p=68</link>
		<comments>http://scribblingpaleo.com/?p=68#comments</comments>
		<pubDate>Mon, 16 Apr 2012 02:24:49 +0000</pubDate>
		<dc:creator>Lucas</dc:creator>
				<category><![CDATA[Cross-posted news articles]]></category>

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		<description><![CDATA[This article will be included in a future publication of the University of California, Riverside research newspaper, InsideUCR.   It’s 5 a.m. on Riverside, California’s Victoria Avenue, and Richard Cardullo is at once aware of the silent, dark world around him, &#8230; <a href="http://scribblingpaleo.com/?p=68">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
			<content:encoded><![CDATA[<p><em>This article will be included in a future publication of the University of California, Riverside research newspaper, </em>InsideUCR. <em> </em></p>
<p>It’s 5 a.m. on Riverside, California’s Victoria Avenue, and Richard Cardullo is at once aware of the silent, dark world around him, his breath, and the sound of his feet hitting the pavement as he runs.</p>
<p>Cardullo enters the fabled runner’s zone at around mile 6. After this point, he knows he can keep running until mile 16, 18, or even 22.</p>
<p>The motivation? Marathons. And not just half marathons: full marathons. The 26.2 mile kind. The kind where, by the end, you feel like a bag of jello-y noodles.</p>
<p>Cardullo, a biology professor at the University of California, Riverside, began running marathons 14 years ago after some of his undergraduate students put him up to the challenge. “I expect my students to do their best, and those students expected the same from me,” he said. “They threw down the gauntlet.”</p>
<p>So, after 10 weeks of training in a UC Riverside fitness class filled mostly with undergraduates, Cardullo ran his first marathon. This first go was arduous and painful–for two weeks after the run, Cardullo was achingly sore from head to toe.</p>
<p>But he was hooked. In the ensuing years, Cardullo ran 10 more marathons.</p>
<p>One of the best things about marathon running, Cardullo says, is training with others. A member of the Riverside Roadrunners club, he is his team’s pace leader, which refers to an experienced marathoner who makes sure his fellow runners are keeping up with their pace and training.</p>
<p>When asked to share some of his pace leader knowledge, Cardullo explained how a marathon is as much a physical challenge as it is a mental challenge.</p>
<p>“A marathon is really two races in one: the first 20 miles, which is mostly a physical test, and the last 6 miles, which is mostly mental,” he said. “During those last 6, the pain, exhaustion, and the dehydration all start playing tricks with your mind, and maintaining focus during this critical period is really the hardest part about finishing.”</p>
<p>Working to master both parts of the marathon has paid off for Cardullo: he ran his first (and worst) marathon in 5 hours, 38 minutes, and has since improved his time to 4 hours, 39 minutes.</p>
<p>Cardullo’s progress hasn’t always gone smoothly, however. During one LA Marathon, he ran just after having had pneumonia. While deemed fit to run by a doctor, Cardullo staggered and hit a physical and psychological wall at mile 16.</p>
<p>“You’re running along, and all of a sudden you have no energy, no focus, you feel something akin to a deep depression, and you have major pain…you literally feel like you have nothing left,” he said. “Hitting walls like this one is why no one ever said running marathons was easy.”</p>
<p>As a matter of self-fulfillment, Cardullo is resolved to meet the challenge. This resolve fuels his running, as well as other parts of his life. On top of marathons, Cardullo researches the biophysics of sex cells, teaches biology courses, sings in two local choirs, and spearheads science education outreach efforts at local K-12 schools.</p>
<p>Truly, a marathon professor.</p>
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		<title>A Climate of Change</title>
		<link>http://scribblingpaleo.com/?p=65</link>
		<comments>http://scribblingpaleo.com/?p=65#comments</comments>
		<pubDate>Sun, 15 Apr 2012 10:23:39 +0000</pubDate>
		<dc:creator>Lucas</dc:creator>
				<category><![CDATA[Cross-posted news articles]]></category>

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		<description><![CDATA[The article was written as a companion piece to a NASA-sponsored, climate change-focused public outreach fair. Carbon dioxide. Melting ice caps. Crop failure. Endangered polar bears. While the news media has delivered these global warming-related sound bites to us, how &#8230; <a href="http://scribblingpaleo.com/?p=65">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
			<content:encoded><![CDATA[<p><em>The article was written as a companion piece to a NASA-sponsored, climate change-focused public outreach fair.</em></p>
<p>Carbon dioxide. Melting ice caps. Crop failure. Endangered polar bears.</p>
<p>While the news media has delivered these global warming-related sound bites to us, how many people could accurately explain the basic science of climate change to a friend?</p>
<p>Probably not many. Recent Gallup polls show that most of us are aware climate change is occurring, but 50 percent of surveyed Americans think climate change in the form of global warming is human-induced ­– this despite the fact that scientists have shown human-induced warming to be unequivocal.</p>
<p>This divide reflects a fundamental misunderstanding of climate change science, and is one reason why agencies, like NASA, are underway with efforts to teach the public about climate science.</p>
<p>Educating the public about the science behind climate change is essential, especially when some popular media outlets often sensationalize climate change, presenting it as controversial, or as something one chooses to believe in or not.</p>
<p>Whether I choose to believe it or not, it is a fact that Earth’s gravitational field keeps me from flying off the planet, and it is a fact that the ice made of pure water in my drink will melt at temperatures exceeding 0 degrees Celsius.</p>
<p>It is also a fact that carbon dioxide gas will absorb and reemit terrestrial radiation.</p>
<p>This is the main reason why Venus, with an atmosphere that is 97 percent carbon dioxide, has surface temperatures in excess of 750 degrees Fahrenheit (hot enough to melt lead!).</p>
<p>Armed with factual observations about carbon dioxide, we can make the educated guess that, if this greenhouse gasis added to the Earth’s atmosphere, warming will follow.</p>
<p>And we would be right: since the Industrial Revolution of the 19<sup>th</sup> century, the amount of atmospheric carbon dioxide has skyrocketed to levels not seen in the past 650,000 years, and, as a result, global temperatures have risen by about 1 degree Celsius (which may not seem like much, but let’s remember: just 1 degree Celsius is the difference between ice and water!).</p>
<p>According to the US Geological Survey, around 200 million metric tons of carbon dioxideare released by both on-land and under-water volcanoes each year. And, according to the US Department of Energy’s Carbon Dioxide Information Analysis Center human fossil fuel consumption emitted almost 30 billion metric tons of carbon dioxide into the atmosphere in 2008.</p>
<p>Volcanoes, then, emit less than 1 percent of the carbon dioxide that humans today do. In contrast, before the Industrial Revolution, volcanoes dwarfed humans not only in sheer awesome power, but also in amounts of emitted carbon dioxide.</p>
<p>The repercussions of increased carbon dioxide and, thus, global temperatures, are severe. Sea level rise will inundate coastal communities, and the ranges of tropical diseases like malaria will increase – to name just two effects.</p>
<p>In order to ensure volcanic carbon dioxide emissions once again dwarf our own, the science behind human-induced global warming needs to be effectively communicated to the public.</p>
<p>But climate science observations, like those presented here, are rarely discussed on our news channels.</p>
<p>So how, then, can we get the message across?</p>
<p>One solution: outreach events. Specifically outreach events that are (1) organized and run by climate change experts and (2) accessible to anyone.</p>
<p>Earlier this month, I volunteered at one such event, called “Refresh Riverside! A Community Climate Fair,” at the University of California, Riverside.</p>
<p>Supported by a NASA grant, Refresh Riverside featured fun and engaging educational booths and activities, each with a specific climate change-related theme.</p>
<p>From carbon dioxide to melting ice caps and sea level rise, fairgoers learned about basic climate change facts and concepts from UC Riverside and NASA scientists.</p>
<p>More than 650 adults and children attended the fair in spite of rain. Such a high number indicates to me a strong public desire of the public to learn the facts about climate science.</p>
<p>When I asked one fairgoer, a middle school student named Nick, what he had learned, he explained how water, when heated, will expand, and how this can contribute to sea level rise.</p>
<p>Where a classroom lecture may not have easily succeeded with Nick, a community climate fair had in conveying an important climate science fact.</p>
<p>Just as rewarding to me was that Nick’s mother, Michelle, who stood proudly by his side, said, “I’m also here to learn.”</p>
<p>&nbsp;</p>
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		<title>Oxygen-free Early Oceans Likely Delayed Rise of Life on Earth</title>
		<link>http://scribblingpaleo.com/?p=24</link>
		<comments>http://scribblingpaleo.com/?p=24#comments</comments>
		<pubDate>Sun, 15 Apr 2012 09:30:00 +0000</pubDate>
		<dc:creator>Lucas</dc:creator>
				<category><![CDATA[Cross-posted news articles]]></category>

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		<description><![CDATA[This article first appeared in a January 2011 issue of the University of California, Riverside research newspaper, InsideUCR New findings illustrate how earliest life on planet co-evolved with oceanic chemistry RIVERSIDE, California – Geologists at the University of California, Riverside have &#8230; <a href="http://scribblingpaleo.com/?p=24">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
			<content:encoded><![CDATA[<p><em>This article first appeared in a January 2011 issue of the University of California, Riverside research newspaper, </em>InsideUCR</p>
<p><em>New findings illustrate how earliest life on planet co-evolved with oceanic chemistry</em></p>
<p>RIVERSIDE, California – Geologists at the University of California, Riverside have found chemical evidence in 2.6-billion-year-old rocks that indicates that Earth’s ancient oceans were oxygen-free and, surprisingly, contained abundant hydrogen sulfide in some areas.</p>
<p>“We are the first to show that ample hydrogen sulfide in the ocean was possible this early in Earth’s history,” said Timothy Lyons, a professor of biogeochemistry and the senior investigator in the study, which appears in the February issue of <em>Geology</em>. “This surprising finding adds to growing evidence showing that ancient ocean chemistry was far more complex than previously imagined and likely influenced life’s evolution on Earth in unexpected ways – such as, by delaying the appearance and proliferation of some key groups of organisms.”</p>
<p>Ordinarily, hydrogen sulfide in the ocean is tied to the presence of oxygen in the atmosphere. Even small amounts of oxygen favor continental weathering of rocks, resulting in sulfate, which in turn gets transported to the ocean by rivers. Bacteria then convert this sulfate into hydrogen sulfide.</p>
<p>How then did the ancient oceans contain hydrogen sulfide in the near absence of oxygen, as the 2.6-million-year-old rocks indicate? The UC Riverside-led team explains that sulfate delivery in an oxygen-free environment can also occur in sufficient amounts via volcanic sources, with bacteria processing the sulfate into hydrogen sulfide.</p>
<p>Specifically, Lyons and colleagues examined rocks rich in pyrite – an iron sulfide mineral commonly known as fool’s gold – that date back to the Archean eon of geologic history (3.9 to 2.5 billion years ago) and typify very low-oxygen environments. Found in Western Australia, these rocks have preserved chemical signatures that constitute some of the best records of the very early evolutionary history of life on the planet.</p>
<p>The rocks formed 200 million years before oxygen amounts spiked during the so-called “Great Oxidation Event” – an event 2.4 billion years ago that helped set the stage for life’s proliferation on Earth.</p>
<p>“Our previous work showed evidence for hydrogen sulfide in the ocean more than 100 million years before the first appreciable accumulation of oxygen in the atmosphere at the Great Oxidation Event,” Lyons said. “The data pointing to this 2.5 billion-year-old hydrogen sulfide are fingerprints of incipient atmospheric oxygenation.&#8221;</p>
<p>Now, in contrast, our evidence for abundant 2.6 billion-year-old hydrogen sulfide in the ocean – that is, another 100 million years earlier – shows that oxygen wasn’t a prerequisite. The important implication is that hydrogen sulfide was potentially common for a billion or more years before the Great Oxidation Event, and that kind of ocean chemistry has key implications for the evolution of early life.&#8221;</p>
<p>Clint Scott, the first author of the research paper and a former graduate student in Lyons’s lab, said the team was also surprised to find that the Archean rocks recorded no enrichments of the trace element molybdenum, a key micronutrient for life that serves as a proxy for oceanic and atmospheric oxygen amounts.</p>
<p>The absence of molybdenum, Scott explained, indicates the absence of oxidative weathering of the continental rocks at this time (continents are the primary source of molybdenum in the oceans). Moreover, the development of early life, such as cyanobacteria, is determined by the amount of molybdenum in the ocean; without this life-affirming micronutrient, cyanobacteria could not become abundant enough to produce large quantities of oxygen.</p>
<p>“Molybdenum is enriched in our previously studied 2.5 billion-year-old Archean rocks, which ties to the earliest hints of atmospheric oxygenation as a harbinger of the Great Oxidation Event,” Scott said. “The scarcity of molybdenum in rocks deposited 100 million years earlier, however, reflects its scarcity also in the overlying water column. Such metal deficiencies suggest that cyanobacteria were probably struggling to produce oxygen when these rocks formed.</p>
<p>“Our research has important implications for the evolutionary history of life on Earth,” Scott added, “because biological evolution both initiated and responded to changes in ocean chemistry. We are trying to piece together the cause-and-effect relationships that resulted, billions of years later, in the evolution of animals and, ultimately, humans. This is really the story of how we got here.”</p>
<p>The first animals do not appear in the fossil record until around 600 million years ago – almost two billion years after the rocks studied by Scott and his team formed. The steady build-up of oxygen, which began towards the end of the Archean, played a key role in the evolution of new life forms.</p>
<p>“Future research needs to focus on whether sulfidic and oxygen-free conditions were prevalent throughout the Archean, as our model predicts,” Scott said.</p>
<p>Lyons and Scott were accompanied on this project by Christopher Reinhard from UCR; Andrey Bekker from the University of Manitoba, Canada; Bernhard Schnetger from Oldenburg University, Germany; Bryan Krapež from the Curtin University of Technology, Western Australia; and Douglas Rumble III from the Carnegie Institution of Washington, Washington, DC. Currently, Scott is a postdoctoral researcher at McGill University, Canada.</p>
<p>Funding for this work came from the National Science Foundation, the NASA Exobiology Program, the NASA Astrobiology Institute, and through a Canadian National Sciences and Engineering Research Council Discovery Grant.</p>
<p><em>This article was published in a 2011 issue of the <a href="http://www.insideucr.ucr.edu/cgi-bin/display.cgi">InsideUCR</a> newspaper</em></p>
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