Earth Perhaps Not Such a Benevolent Mother After All

Most of us think of Earth as a nurturing place, with a natural equilibrium where life thrives and flourishes.

Some refer to that idea as the Gaia hypothesis, named for the ancient Greek goddess of Earth. The Gaia hypothesis suggests that the planet behaves as a kind of giant organism, with its complex systems finely tuned to compensate when one system gets out of kilter.

But Peter Ward, a University of Washington paleontologist, says that it is the Gaia view that is out of kilter. Ward has looked closely at conditions that existed during numerous mass extinction events in Earth's history to draw the conclusion that the Earth maybe isn't such a hospitable, harmonious nurturing mother after all.

In a new book, he suggests the planet ultimately is inhospitable to life, and that life itself might be the primary reason. Rather than Gaia, he invokes the darker Medea from Greek mythology.

"The Medea hypothesis says life is already shutting down Earth as a habitable planet. Not just the diversity of life, but the actual biomass," Ward said. "Life keeps evolving, and there are unintended, often negative, consequences."

"The Medea Hypothesis: Is Life on Earth Ultimately Self-Destructive?" was published in April by Princeton University Press. In the 208-page book, Ward argues that humans have to use engineering to manage their environment or face potential extinction if the Earth is left to manage itself.

"The engineering I'm talking about is not girders and sky shields. It's engineering microbes to take over food production and energy production," he said.

Microbes have undergone evolution, a sort of natural engineering, throughout Earth's history, he said, and humans have the ability to guide such changes to clean the environment, for example, or regulate carbon dioxide in the atmosphere.

Like Gaia, Medea is a mythological character, though she is decidedly much darker in nature. Medea was married to Jason at the time he pursued the Golden Fleece but, according to legend, he left her and in revenge she killed their two children.

Ward, a UW professor of biology and of Earth and space sciences, says numerous mass extinctions show that our planet behaves in somewhat the same way. For example:

**The evolution of oxygen-producing organisms twice plunged Earth into ice ages as carbon dioxide, crucial for photosynthesis, was stripped from the atmosphere.

**The evolution of the first true animals caused extinction of most stromatolites, layers of microbes living in sediment in the oceans' intertidal zones. The result was somewhat more complex life forms, but a vastly smaller volume of living matter.

**The evolution of the first forests 400 million years ago is considered one of the great events in Earth history. But tree roots pushed into subsurface rocks, exposing them to increased weathering. The weathered elements again stripped carbon dioxide from the atmosphere and plunged the Earth into a 90 million-year ice age.

"The irony is that we have way too much carbon dioxide right now, but we should stash it in a bank because we're going to need it," Ward said. "The end of life as we know it is when we reach just 10 parts per million of carbon dioxide in the atmosphere."

Currently, carbon dioxide is at 380 parts per million and rising, creating a greenhouse effect that most climate scientists say will greatly increase temperatures around the world, with some severe consequences. For example, with the melting of mountain and polar ice sheets, the world's most-productive agricultural land will be submerged and humans will struggle to find food, Ward said.

He noted that throughout Earth's history, carbon has been stripped from the atmosphere and stored in trees, rocks, even the oceans. He said those processes will continue until atmospheric carbon dioxide drops to 10 parts per million, a point at which no plants can live. Once plants are gone, within 20 million years the oxygen will plummet to 1 percent of the total atmosphere and life as we know it will end.

"Then you've gotten to a point where it will be forever impossible to get diversity of life back. It will be forever impossible to regain an oxygen-rich atmosphere. That's not Gaia. It's the opposite of Gaia," he said.

He notes that of 15 mass extinction events in Earth's history, only the one 65 million years ago that brought an end to the age of dinosaurs was likely caused by a comet or asteroid crashing into the planet's surface. The others all resulted from Earth's own processes.

"There's no Gaia. There's just this dumb, blind life. It tries out all kinds of new things that are good for new kinds of life but are detrimental to everything else that exists. The innovations lead to disaster," Ward said.

He added that, contrary to recently popular beliefs, the planet likely would not somehow "heal itself" if all humans were suddenly removed. Instead, he said, humans are the key to saving the planet and, in the end, are perhaps the only true Gaian force.

"We're not renting. We're the owners, but there can be a cost to the rest of nature of our ownership," Ward said. "There is an easy fix – the only fix is intelligence. Knowing that there is a problem is what will get us out of it. We're the only ones who can put our hands on the controls."

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Biofuel Production: a Drink-Or-Drive Issue?

Federal requirements to increase the production of ethanol has developed into a "drink-or-drive issue" in the Midwest as a result of biofuel production's impact on water supplies and water quality, says an environmental engineering researcher at Missouri University of Science and Technology in the latest issue of the journal Environmental Science & Technology.

In an analysis of the water required to produce ethanol from various crops, Dr. Joel G. Burken, a professor of environmental engineering at Missouri S&T, and colleagues from Rice University and Clarkson University find that ethanol could become a costly proposition in terms of "gallons per mile" and other water quality issues. They describe the Midwest's water needs and impacts as the 'water footprint' in their cover feature for the May 1 issue of Environmental Science & Technology. The researchers report that ethanol derived from corn grown in Nebraska, for example, would require 50 gallons of water per mile driven, when all the water needed in irrigation of crops and processing into ethanol is considered. Fuel derived from irrigated sorghum grown in that state would require even more water to produce - as much as 115 gallons per mile.

Moreover, increasing production of biofuels from row crops will likely result in more water pollution due to soil erosion and the increased use of pesticides to grow enough crops to meet federal mandates for more ethanol, the researchers say. The mandated production using the current technology has driven the use of ethanol production from corn and biodiesel from soybeans as these are the currently available technologies.

In their Environmental Science & Technology article, the researchers suggest that federal regulators take a closer look at how a push for bioenergy will affect water resources.

"Developing a sustainable national biofuels program requires careful consideration of logistical concerns ... and of unintended environmental impacts," write Burken and his co-authors, Rosa Dominguez-Faus and Dr. Pedro J. Alvarez of Rice University and Dr. Susan E. Powers of Clarkson University, in their article, "The Water Footprint of Biofuels: A Drink or Drive Issue?" The article is online at http://pubs.acs.org/doi/abs/10.1021/es802162x.

To arrive at their gallons-per-mile figures, the researchers first looked at the amount of water required to produce a single gallon of ethanol. In Nebraska, for example, it takes 800 gallons of water - from crop irrigation through final processing into ethanol - to create a single gallon of the corn-derived transportation fuel. Divide that by an average mileage of 16 miles per gallon (or two-thirds the average for gasoline-powered cars, a standard average for ethanol-powered vehicles), and the result is 50 gallons of water per mile.

While previous studies have examined biofuel production's impact on air quality, land use and net energy value, "the effect of increased biofuel production on water security has not been subjected to the same scrutiny," the researchers write. The main focus of previous studies looked at environmental trade-offs to fossil-fuel usage and not other aspects of biofuel production, according to the researchers.

"The overall water footprint associated with biofuels must recognize the impact of increased agricultural activity on water quality as well as water consumption," they write. With the federal Energy Independence and Security Act (EISA) of 2007 calling for a dramatic ramp-up in ethanol production by 2015, Burken and his colleagues foresee additional water quality problems due to "increased agricultural activity such as tilling more land for row crops and higher fertilizer and agrichemical application."

The Energy Independence and Security Act requires the United States to produce 15 billion gallons of corn-derived ethanol annually by 2015 and 16 billion gallons of fuel from cellulosic crops, such as switchgrass, by 2016. The researchers note that 44 percent of all the corn produced in the United States from 2007 would be required for ethanol production to meet the 2015 goal.

"The decision to mandate ethanol production may look great initially as we all like the concept of biofuels," Burken says, "but really our difficult energy position and reliance on foreign oil is the result of our lack of an energy policy and investing a decade ago in biofuel technologies. Biofuel production is part of our energy future, but it needs to be considered as part of a portfolio of energy sources and technologies."

While it's unlikely the EISA will be repealed, Burken hopes lawmakers and regulators at the state and federal levels "consider a life-cycle analysis before implementing future mandates" for energy sources. Lawmakers and regulators need to consider all of the economic and environmental trade-offs - not just reducing greenhouse gas emissions, for instance. "Otherwise, we may be thinking we're addressing one environmental issue while in fact sacrificing another," Burken says.

Burken and his colleagues suggest that "drought-tolerant, high-yield plants grown on little irrigation water" would have less impact on water resources. One such crop, Burken says, is miscanthus, a fast-growing perennial grass that "grows so dense you can't walk through it and grows about 9-10 feet a year." Currently, however, no technology is available to convert the cellulosic biomass and produce it in large quantities. Once alternative biofuel production crops and processes are developed, selecting the best crop for individual settings will help to optimize biofuel production and minimize the environmental impacts of the production, Burken says.

"Developing the crops and distribution of crop production took about 100 years to get to where it was a few years ago," Burken says. "Redeveloping this production with the goal of biofuel production will take time and effort of farmers and engineers. While miscanthus may or may not be a part of our biofuels future, we at least need a little time and investment to develop the best solutions for our future."

Quoting Texas oilman T. Boone Pickens, whom Burken met on April 22 during the Missouri Energy Summit, Burken says, "The best time to plant a tree was 20 years ago, but the next best time if you didn't is today."

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Most Emailed: Genetic Study Finds Treasure Trove of New Lizards

A detailed genetic study of the Australian gecko genus reveals many more species of Australian lizards than previously thought, increasing the recognized number of gecko species, from 13 species to 29.

This raises new questions about conservation and management of Australia's native reptiles.

"One of the major problems for biodiversity," says Paul Oliver, a PhD student at the University of Adelaide who participated in the genetic gecko research, "is that many species remain undocumented.

"This problem is widely acknowledged to be dire among invertebrates and in developing countries. But in this group of vertebrates in a developed nation, which we thought we knew reasonably well, we found more than half the species were unrecognised."

From the article:

University of Adelaide research has discovered that there are many more species of Australian lizards than previously thought, raising new questions about conservation and management of Australia's native reptiles.


PhD student Paul Oliver, from the University's School of Earth and Environmental Sciences, has done a detailed genetic study of the Australian gecko genus Diplodactylus and found more than twice the recognised number of gecko species, from 13 species to 29. This study was done in collaboration with the South Australian Museum and Western Australian Museum. "Many of these species are externally very similar, leading to previous severe underestimation of true species diversity," says Mr Oliver.


"One of the major problems for biodiversity conservation and management is that many species remain undocumented.


"This problem is widely acknowledged to be dire among invertebrates and in developing countries.


"But in this group of vertebrates in a developed nation, which we thought we knew reasonably well, we found more than half the species were unrecognised."


Mr Oliver says this has great significance for conservation. For instance, what was thought to be a single very widespread species of gecko has turned out to be eight or nine separate species with much narrower, more restricted habitats and possibly much more vulnerable to environmental change, he says.


"This completely changes how we look at conservation management of these species," he says.


"Even at just the basic inventory level, this shows that there is a lot of work still to be done. Vertebrate taxonomy clearly remains far from complete with many species still to be discovered. This will require detailed genetic and morphological work, using integrated data from multiple sources. It will require considerable effort and expense but with potentially rich returns."


A paper on this study 'Cryptic diversity in vertebrates: molecular data doubles estimates of species diversity in a radiation of Australian lizards (Diplodactylus, Gekkota)' is published online today in Proceedings of the Royal Society: B.

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Argentine Penguins Have Happy Feet

The Government of Argentina recently signed into law the establishment of a new coastal marine park in a wildlife-rich coastal region of South America. The Bronx Zoo-based Wildlife Conservation Society has succeeded in working with Argentina to protect this region's diverse ecosystem, which includes half a million penguins, several species of rare seabirds, and the region's only population of South American fur seals. It is the first protected area in Argentina specifically designed to safeguard not only onshore breeding colonies but also areas of ocean where wildlife feed at sea.

The Bronx Zoo-based Wildlife Conservation Society announced today that its efforts to protect a wildlife-rich coastal region in South America have paid off in the form of a new coastal marine park recently signed into law by the Government of Argentina.

The park, which became official earlier this month, protects half a million penguins along with several species of rare seabirds and the region's only population of South American fur seals. It is the first protected area in Argentina specifically designed to safeguard not only onshore breeding colonies but also areas of ocean where wildlife feed at sea.

The park's creation represents a joint effort by the National Parks Service of Argentina, Government of Chubut, Wildlife Conservation Society and its local partner Fundación Patagonia Natural with support from the United Nations Development Programme and the Global Environment Facility.

WCS researchers, working with Fundación Patagonia Natural, provided critical data of key wildlife to ensure that the park's boundaries would include both onshore areas and adjacent waters. Researchers found that the area was in need of protection from increasing pressures by commercial fishing and the oil industry.

"The park protects one of the most productive and extraordinary marine ecosystems on the planet," said Dr. Guillermo Harris, director of the Wildlife Conservation Society's Argentina Program. "The creation of this park comes in the nick of time for many species that are threatened by the region's fishing and energy industries."

Located in Golfo San Jorge in Chubut Province, some 1056 miles (1700 kilometers) south of Buenos Aires, the new protected area covers approximately 250 square miles (647 square kilometers) of coastal waters and nearby islands strung along almost 100 miles (160 kilometers) of shoreline.

The region serves as a nesting and feeding ground for some quarter million pairs of Magellanic penguin, estimated to represent 25 percent of the entire population in Patagonia. Its 50 small islands also support two nesting colonies of southern giant petrels that represent over 80 percent of its population on the entire Patagonian coast. Other denizens of this coastal oasis include the endangered Olrog's gull, the white-headed steamer duck, and almost one third of all imperial and rock cormorants of Argentina.

While the coastline is largely undeveloped, its wildlife has been increasingly threatened by commercial fishing nets, which can entangle birds as they feed. Oil pollution from tankers transporting petroleum from southern Patagonia to Buenos Aires, coupled with expanding offshore oil drilling, have also loomed as growing threats in recent years.

Mitsubishi Corporation Foundation for the Americas has provided funding for the creation of this unique coastal protected area and for WCS's multi-faceted efforts to safeguard coastal Patagonia, including the Sea & Sky program, which is committed to achieving long-term viability of the Patagonian Sea by integrating the best available science, building capacity and providing inspiration to promote local interest in ocean conservation.

WCS has been active in Patagonia since the 1960s, conducting studies for the conservation of southern right whales, Magellanic penguins, southern elephant seals, and other unique wildlife. WCS manages some 740,000 acres of wilderness on the Chilean side of Tierra del Fuego, part of a major donation of land made by Goldman Sachs in 2004.

The Wildlife Conservation Society saves wildlife and wild places worldwide. We do so through science, global conservation, education and the management of the world's largest system of urban wildlife parks, led by the flagship Bronx Zoo. Together these activities change attitudes towards nature and help people imagine wildlife and humans living in harmony. WCS is committed to this mission because it is essential to the integrity of life on Earth. Visit: www.wcs.org

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Deep-Sea Expedition Sets Sail, 20,000+ Students Along for Ride

Newswise — Setting sail on the Pacific, a University of Delaware-led research team has embarked on an extreme adventure that will find several of its members plunging deep into the sea to study hydrothermal vents on the ocean floor.

The team will be conducting research in environments that include scalding heat, high pressure, toxic chemicals and total darkness, as part of the National Science Foundation-funded “Extreme 2008: A Deep-Sea Adventure.”

The scientists are being joined by students from around the world on dry land who have signed up for an exciting virtual field trip. More than 20,000 students from 350 schools in the United States, Aruba, Australia, Canada, Costa Rica, Great Britain and New Zealand are participating.

The expedition, led by Craig Cary, professor of marine biosciences in the University of Delaware’s College of Marine and Earth Studies, left Monday, Nov. 10, aboard the research ship Atlantis from a port in Manzanillo, Mexico, with an expected return date of Dec. 1. For those interested in following the scientists, they will blog regularly about the voyage at the Extreme 2008 Web site [http://www.expeditions.udel.edu/extreme08].

Team members – researchers and graduate students – are from the University of Delaware, the University of Colorado, University of North Carolina, University of Southern California, J. Craig Venter Institute, Universidad Nacional Autónoma de México and the University of Waikato, New Zealand.

The team is heading to destinations at two hydrothermal hot spots: Guaymas Basin in the Gulf of California and a group of vents in the eastern Pacific Ocean about nine degrees north of the equator.

Once above the vents, the researchers will take the submersible Alvin down from one to nearly two miles below the surface. Built to withstand crushing pressures and to pierce the utter blackness of the deep, Alvin will let the scientists observe life around the steaming vents and collect samples for analysis. Both Atlantis and Alvin are owned by the U.S. Navy and operated by the Woods Hole Oceanographic Institution.

The scientists' focus will be marine viruses and other tiny life called protists. These organisms prey on bacteria, the primary food for vent dwellers ranging from ghost-white vent crabs to bizarre-looking tubeworms.

“For many years, the vents have been explored with little to no attention to viruses and protists,” Cary says. “Yet because these organisms eat bacteria, they have the most dramatic effect on the bacterial communities that support the vent system. Our research programs are among the first to focus on these remarkable scavengers.”

Eric Wommack, an associate professor with joint appointments in both the College of Agriculture and Natural Resources and the College of Marine and Earth Studies, will join Cary in leading the UD contingent.

Wommack, who is based at the Delaware Biotechnology Institute, is an expert on marine viruses and will be deploying specialized equipment to capture them for analysis in the shipboard lab.

Wommack says hydrothermal vents, although characterized by caustic chemistry, hot temperatures and high pressure, are oases of life in the deep sea. The vents provide an ecosystem for ancient and unusual microbes that are capable of extracting energy from volcanic rather than solar energy, and are home to viruses.

“As a group, viruses are the most abundant biological entities on Earth and contain its largest reservoir of unknown genes,” Wommack says. “We know that bacteria at the deep-sea hydrothermal vents are intimately associated with relatively abundant populations of viruses. Our goal is to explore the wilderness of viral genes existing at the vents.”

David Caron, professor of biological sciences in the Wrigley Institute for Environmental Studies at the University of Southern California, will be studying protozoa, a class of protists that feed on other organisms and that may form a crucial bridge between bacteria and animal life.

If Caron is correct, the samples from the deep will show that protozoa feed on bacteria or on the products of bacterial activity and are in turn eaten by larger life forms. The most surprising thing about the theory may be the lack of evidence for it. While other studies have found a protozoan-animal link in surface waters, the analogous middle step in the deep ocean has been overlooked.

“Protozoa are everywhere and they’re in virtually every environment. They play this intermediate food web role in a number of these environments, and there’s no reason to believe that they aren’t doing the same thing in the vents. It simply hasn’t been looked at to any degree,” Caron said.

As the scientists work at sea, they will be connected to students via an interactive Web site, where blogs, dive logs, video clips, photos and interviews will be posted daily. Students also will be able to write to the scientists, design experiments and participate in a virtual science fair.

A capstone experience for selected schools will be a “Phone Call to the Deep,” linking classrooms with researchers working live in the submersible Alvin on the seafloor.

The University of Delaware and the National Science Foundation are sponsoring the expedition. Additional support is being provided by Olympus and by MO BIO Laboratories.

The program, coordinated by the Office of Communications & Marketing, is the sixth in UD's popular “Extreme” series, which has won state and national awards for public education.

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