27 January 2009

Earth's mass extinctions: Peter Ward on TED.com

Asteroid strikes get all the coverage, but "Medea Hypothesis" author Peter Ward argues that most of Earth's mass extinctions were caused by lowly bacteria. The culprit, a poison called hydrogen sulfide, may have an interesting application in medicine. (Recorded February 2008 in Monterey, California. Duration: 19:42.)

Watch Peter Ward's talk on TED.com, where you can download this TEDTalk, rate it, comment on it and find other talks and performances from our archive of 360+ TEDTalks -- including more bold predictions and stern warnings.

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11 January 2009

Peter Ward on Earth's appetite for destruction

Peter Ward spoke at TED2008 about Earth's mass extinctions (watch for his TEDTalk later this month). You probably know about one of these events, the Cretaceous-Tertiary extinction 65 million years ago that ended the age of dinosaurs. In today's Boston Globe, Ward talks with writer Drake Bennett about the other four extinctions -- and about the way our planet seems to careen toward destruction over and over.

Ward's Medea Hypothesis runs counter to the idea that our planet is a self-balancing system; he suggests that, when given the opportunity, any kind of life on Earth, from plants to bacteria to humanity, will run amok and tip the balance toward chaos. From the story:

In his view, the earth's history makes clear that, left to run its course, life isn't naturally nourishing -- it's poisonous. Rather than a supple system of checks and balances, he argues, the natural world is a doomsday device careening from one cataclysm to another. Long before humans came onto the scene, primitive life forms were busily trashing the planet, and on multiple occasions, Ward argues, they came close to rendering it lifeless.

For more details -- and a lively conversation on the Globe site -- read the story, Dark Green: A scientist argues that the natural world isn't benevolent and sustaining: it's bent on self-destruction >>

And contrast this with Jared Diamond's 2005 TEDTalk on collapse -- as one Globe commenter notes: "human beings ... are destructive to the stability of the ecosystems in many cases."

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27 February 2008

TED2008: What is our place in the universe?

(Running notes from the TED2008 conference in Monterey, California. Second session.)

The second session of TED2008 asks "What is our place in the universe?" and it cogently opens with a sneak preview of an amazing piece of technology under development at Microsoft: the World Wide Telescope, a powerful new web-based tool for exploring the universe (for the geeks among you, this is the unnamed piece of new tech that made blogger Robert Scoble weep recently). It functions like a virtual telescope, bringing together imagery from actual ground and space (Hubble) telescopes. Roy Gould and Curtis Wong are up on stage demo-ing it. Gould, who's an astronomy educator, says that the WWT "produces a holistic view of the universe and it's going to change the way we do astronomy and teach it, and the way we see ourselves in the universe. Why do I believe that it is transformative? It enables you to experience the universe; you can tour it, with astronomers as your guides; and you can create your own tours and share them with friends. It will enable a new generation of stories and storytellers". The WWT is indeed impressive, providing an amazing, seamless, very detailed navigational experience in the depths of the universe. Since this has not been seen in public so far, here three screenshots:

The WWT is not live yet -- it's announced for sometimes later in the Spring and will be free for downloading -- but a couple of promo videoclips and background information can be found here.

A telescope of another kind is in Partricia Burchat's curriculum: she's a member of the Large Synoptic Survey Telescope project, which will allow scientists to monitor exploding supernovae and determine how fast the universe is expanding. As a particle physicist at Stanford University and at the Stanford Linear Accelerator Center, Burchat studies the basic ingredients of the universe -- dark matter and dark energy.
"The questions at the smallest and largest scale are actually very connected. Recently we have realized that the ordinary matter of the universe -- you, me, the planes, the galaxies -- makes up only a few percents of the content of the universe. Almost a quarter of the mass in the universe is invisible: it doesn't absorb, reflect or interact with the electromagnetic spectrum. We know it's there -- "it" is dark matter -- because of its gravitational effects.
You saw many images of galaxies in the previous WWT demo. In galaxies most of the mass is concentrated in the center of it. Logically, it would appear that stars that are closer to the mass in the middle rotate at higher speeds. Instead, when measurements are made we find that speed is constant as a function of distance -- which means that there is a gravitational pull from matter that we don't see.
The universe is expanding. The distance between galaxies is getting bigger because the universe is getting bigger. After the Big Bang, space expanded rapidly. But then, instead of slowing down the rate of expansion has been speeding up. This is a surprising scientific result, and there is no persuasive explanation for why it is happening, except for the presence of "dark energy"."

John Hodgman is the resident expert on Comedy Central's "Daily Show". He's an expert on everything -- and on nothing, really, since his expertise is mostly of the comedic kind. His hilarious book "The areas of my expertise" features, among other fakeries, lobster conspiracies and US presidents with hooks for hands. He's also the guy playing "the PC" in the "Mac vs PC" funny ad series (see the one on viruses and the one on spyware). He does a very funny piece on "where is everybody?" and "was Enrico Fermi an alien?" (above left the picture Hodgman used) and his "close encounters".

Contrary to Hodgman, Peter Ward's areas of expertise are multiple and real. A paleontologist and astrobiologist and co-author of "Rare Earth", he has studied mass extinctions and has theorized that complex life forms are so rare that it's possible that Earth is the only place in the universe that has any -- while simple life may exist elsewhere and possibly be very common. He tells a medical/scientific/detective story.
"What does it take for a planet to be liveable, and for sustain complexity. We have to start thinking about what is a good planet and what isn't. Our planet is good because it has water. Mars is a "bad" planet but still good enough for us to go there and live in its surface if protected. Venus is a bad-bad planet, where we couldn't survive (high temperature and clouds of sulfuric acid). Earth, if we are lucky enough (if we are not blasted by a supernova), will live long. But what if there is an accident such as mass extinction? Many researchers believe that cosmic detritus probably caused at least four of the five largest mass extinctions in the last 600 million years. The animals that generally survive mass extinction are cold-bloods, crocodile-like creatures, with a couple of tiny mammals hiding in the fringes. But what if there was no impact?"
There are microbes that produce hydrogen sulfide, that can stop complex life from existing. Ward tells how he learned that mammals, including humans, when inhaling hydrogen sulfide (H2S), go into suspended animation, a sort of coma. They can be "frozen" and then revived hours later (think of the implications for people hurt in an accident -- "this is going to be a revolution"). Why? The only reason mammals could have developed this capacity must have to do with previous periods in history with severe climate changes happened. "Many of the mass extinctions were caused by lowering oxygen levels and H2S being produced out of the oceans. Can this happen again?".

Sri Sri Ravi Shankar (picture right) is not the legendary sitar virtuoso. He's an Indian anti-stress and meditation guru. He emphasizes breathing as the link between body and mind. (He will lead two early-morning meditation sessions for TED attendees tomorrow and Friday).
"Life is to create a "wow". Everyone can experience the "nirvana" Jill Taylor was talking about earlier. When we die, the first thing is that breath will stop. The first thing we do when we are born is breathing. But rarely we take the time to think about that. Breath hold the secret to our mind, to our inner life, and there are patterns in our breath that link us to the universe. If you remember this morning when you woke up, what was the state of your mind? And one hour later, what was the state of your mind? As the sun rises and sets, the patterns of your breathing change. If you breath through the left nostril, there is more right-brain activity. When you're breathing through your right nostril, there is faster metabolism, you understand things better, your perception is better, logic is better. By learning breathing techniques, you can get over tendencies of depression, alcoholism, stress, confusion, learn to defeat negative emotions. We have to see ourselves in a biggest context, the context of the universe."

Closes the session Kaki King, with a show of her extended guitar techniques (watch her on Youtube).

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