Airliner Chronicles Follow-Up

Thanks for the comments on the previous post; here is a ground level photo to provide some context to the picture. We are in northern California...

Picture of the Day - The Airliner Chronicles Part 11

I've been flying you all over glacial landscapes of Canada and Greenland the last couple of days, but for a brief change of pace, here's a bit of a geological mystery from the air. It's in North America, and if someone doesn't recognize it right away, and if no one tries to solve it, I'll toss in some clues later. There is an interesting story of geological assumptions and perceptions associated with this region. Have at it!

Picture of the Day - The Airliner Chronicles Part 10

Back to the air...sorry, no context for this one, because United doesn't provide a GPS tracker. I can only say it was in northern Canada somewhere, and southwest of Baffin Island. I dunno, do continental glaciers have any influence on a landscape? And just what is a deranged stream pattern anyway? Lots of kettle lakes here.

Why I Blog - Notes from a Rookie in the Geoblogosphere

Brian at Clastic Detritus asks about what the science blogs are, and whether they seem to fall into categories: blogs about science, or blogs by scientists? It's an interesting question, and I don't think I've been here long enough to put myself in one category or another. Mostly I started this blog after spending a great deal of my online time following politics in the blogosphere, and realizing slowly that we now have an alternative form of communication that has some great potential in my field of education and earth science.

Consider that in politics, blogs pretty much didn't exist in the public conciousness prior to the presidential elections in 2004, but they have grown in influence to the point that many people get their news there instead of the mainstream media, because of a perceived corporate bias (take your choice, left or right). These blogs have been able to influence the direction and intensity of public discussion on a number of important political issues, and have even successfully changed the expected results of a number of elections (just ask Joe Lieberman in Connecticut). The blogs have become a sort of ultimate democracy, and sort of an ultimate anarchy at the same time. You have to be able to filter out the accurate information from the garbage.

I have been watching the fledgling geoblogosphere from the margins for the last year or so, and was disappointed that it didn't seem to include much of anyone at first beyond Andrew Alden's About Geology (apologies to everyone I missed...), and I sort of wandered away during a very busy spring and summer, and when I came back, I found that the number of interesting and active geoblogs had vastly increased.

What is the role of the geoblogosphere?

At conferences and in the journals, our science is presented in a very formal way, and there are the very appropriate guidelines and buffers and peer reviews that promote an intellectual honesty that our science disciplines must maintain at all costs. I love going to conferences when I have the chance, but I also note the some of the best parts of the attending these gatherings is the chance to meet other teachers and other geologists over coffee or beer, and getting to know them as individuals and friends. We can toss out our opinions and jokes, and trade teaching ideas, all in an informal atmosphere of give and take.

As I observe the Accretionary Wedge carnival, and the Where on (Google) Earth contests float through the geoblogosphere, I realize that I am participating in the same kind of friendly communication that I previously did during the off-moments of conferences. It is a chance to find out something else about our colleagues that doesn't emerge in a formal paper or session. Sometimes just plain fun, but I also see great potential for a rapid mobilization when major issues arise. I am remind, for instance, of attempts to shut down the USGS to save a small, small portion of the federal budget. I can recall a few times when very famous geologic outcrops were threatened by short-sighted road beautification projects. It is good to know that if such problems arise, a concerted effort by geobloggers can make a significant difference in resolving the problem.

In my own case, it really boils down to the fact that I have a whole bunch of pictures that I want to share, and I enjoy discussing geological/educational stuff in a setting that allows for informality and the occasional stupid comment (NOVAblog, I was kidding about the coal-burning power plant). I've been enjoying it so far, and hope to continue making contributions. And I would really like to see more people make the plunge and start their own geoblogs. There should be more of you participating, both students, teachers and researchers. I found it to be a very straight-forward process starting and adding to the blog, and truly a lot less hassle then maintaining my formal website. It actually is a great deal of fun. I am living proof that you don't have to be particularly smart or sophistocated to do it.

Nice Exercise in Modeling 3-D Concepts

Hat-tip to Kim at All My Faults are Stress Related for this link to Steven Reynolds and company at Arizona State University and their internet exercise on understanding three dimensional structures: Geoblocks 3D. It is a great use of graphics that goes a huge step further than chalk drawings of folds and faults. Check it out!

Patriots Win Superbowl! Don't believe the so-called "Experts" who tell you otherwise

This is too good to pass up! Lab Lemming has definitive proof that the Giants DID NOT win the Superbowl yesterday. Check it out: Global warming skeptics claim Patriots win Superbowl. It is an inconvenient truth that all those sports writers got it wrong.

Why I Teach - The Long Journey of the Australian Marsupials

If anyone wonders why I teach at a community college, and why I don't dabble much in research, it would be because I have a scientific version of attention-deficit disorder: as soon as I start concentrating on one subject, something interesting pops up somewhere else, and I explore it for a few weeks, and then get distracted by something else. My students love it; there is almost always some weird tidbit of information that will pop up in classroom discussions. And hopefully it is a disorder that works well with running an interesting geoblog.

I was reminded of this when I saw this article in National Geographic News (Ancient Lion With "Bolt Cutter" Jaws: Best Killer Ever?) about the Australian marsupial version of a lion(Thylacoleo carnifex). Apparently, the creature had one of the strongest bites of any carnivore, and those cuddly kangaroos once had a most fearsome predator in their midst. In fact, they had more than just one.

Generally, when students are presented with the biographical evidence for plate tectonics and continental drift, it involves a discussion of mammal-like reptiles, and the distribution of the glossopteris flora across the southern hemisphere. This makes sense, given the role they played in Alfred Wegener's fight to have continental drift accepted as a plausible scientific hypothesis.

On the other hand, the story of the marsupials is a fascinating tale of journeys across vast continents, incredible adventures in successful adaptation, and horrific tragedies of extinction in unlikely places and times, as well as the on-going extinction event that is seeing the probable disappearance of koalas, tasmanian devils, and others. After a discussion of which continent has been isolated the longest, most students guess Australia, on the basis that the continent hosts the most unique mammal ecosystem, the marsupials. I am then able to point out that the ecosystem was once much richer. For nearly every animal filling an environmental niche in the more familiar climes of Europe and North America, there was an equivalent creature in Australia. For the antelope and deer, there are kangaroos and wallabies. For mice and rats, there are opossums and marsupial mice. For cats there are quolls. A stretch, perhaps, but for pigs, there are wombats. For foxes, we find the Tasmanian Devil. Less than a century ago there were Tasmanian wolves (hunted to extinction by 1930). In the paleontological record, we find a 3-ton marsupial buffalo or cow equivalent (diprotodon), and the subject of the linked article, the Marsupial lion, Thylacoleo carnifex. There was even a carnivorous species of kangaroo (Ekaltadema ima)!

The next obvious assumption is that marsupials originated in Australia. Why not? It makes sense that the most complex ecosystem of marsupials on earth must have arisen on the continent where they are found today. But they did not originate there, and were in fact relative late-comers to Australia.

The oldest marsupials known are reported from China, from Mesozoic time. My students immediately assume these marsupials got to Australia via the Indonesian Islands, which brings up the Wallace Line, which is a clear demarcation between many kinds of animals that exist on either side. The concept dates from the 1800's, and is in fact the work of Alfred Wallace, of evolutionary theory fame. The reason is tectonic. The continents are currently moving closer, and have been much further apart, making island-hopping essentially impossible.

Instead, the fossil records chronicles the successive arrival of later marsupials in North America, South America, Antarctica, and finally Australia. The distribution of these creatures makes no sense if the continents are stationary: they couldn't and wouldn't swim such distances. Instead, the journey of the marsupials is a fascinating line of evidence that supports the one-time existence of Pangea, Laurasia and Gondwana. And the story doesn't end there...

South America once supported a thriving marsupial ecosystem, including a marvelous example of convergent evolution in the existence of a sabertooth marsupial cat. It survived until around 4 million years ago, when the isthmus of Panama linked north and south America, allowing predators, especially the big cats, to move south, and treat South America like a giant buffet. The marsupials were decimated for the most part. On the other hand, the marsupial rat (the Virginia opossum) thrived in competition with North American placental species, and expanded its range into the United States.

It is a privilege and a joy to be a teacher. I've been thinking about this month's geoblogosphere carnival (subject, "what things make us go hmmm?"; see http://lablemminglounge.blogspot.com/2008/01/accretionary-wedge-5-and-6.html). I may end up with wondering what it is we do to destroy a student's sense of wonder about all things scientific. More to come....