Science Friday

The 'internets' get a lot of grief sometimes and so I feel it is my duty to stick up for them whenever possible. Bless those little tubes.

The reason this struck me today was that I was in my car this morning when Science Friday came on NPR. There were two interesting stories of direct relevance to this class but I had other (out of the car) things to do. Thanks to the wonders of the Internet I was able to download the two segments later and listen to them at my leisure.

The first segment (link to mp3 file) concerns the evolution of man. Researchers working in Kenya have found fossils indicating that Homo habilis did not give rise to Homo erectus, as previously thought, but the two existed at the same time, with Homo erectus and Homo habilis both evolving from a common ancestor 2 to 3 million years ago. The paper is to be published in the journal Nature this week.

The second segment (link to mp3 file) described how researchers have been able to extract frozen bacteria up to eight million years old from Antarctic ice samples. They were able to revive the bacteria and the bacterial colonies began to grow again. This research is published this week in the journal Proceedings of the National Academy of Sciences.

This time last year: GM plant escapes into wild

Rise of dinosaurs not so rapid after all.

I didn't want to let this press release from researchers in Integrative Biology at UC Berkeley slip by. They showed, for the first time, that dinosaurs and their non-dinosaur ancestors lived side by side for tens of millions of years, disproving the notion that dinosaurs rapidly replaced their supposedly outmoded predecessors.

The finds, including fossil bones of a new dinosaur predecessor the researchers have named Dromomeron romeri, are described in a cover story in the July 20 issue of Science.

This time last year: 100 Ecological Questions and Global Warming threatens California Wine Industry

Evolution is easy!

Thanks to the wonderful folks at BoingBoing (a directory of wonderful things) for directing my attention to this fabulous cultural artifact: a Red Queen Barbie doll! Part of a new line of Alice in Wonderland Barbie toys. Buy this one and all your other Barbie dolls will have to run twice as fast just to keep up.

The only disappointment is how, well, static, the Red Queen looks. Perhaps she should come with a catapult launcher.....

Although Barbie is well known for his difficulty with math she has already revealed a fondness for evolution: witness the Paleontologist Barbie. I love the 'Dinosaur Quiz' on the back - 'if you get five or more right you should consider a career in paleontology too!' Sadly the text is too small to read the actual questions. Although I think one of them may be 'What does Dinosaur mean?' Fortunately diligent searching of the ebay archives produces this better image. Now you too can take the quiz and even check the answers to find out if you too can be a paleontologist!

This time last year: Ecological Footprints and Summer Reading part 2

When Giant Penguins Roamed the Tropics and other Snippets

What a great word: 'Snippets'.

A good way to get entertained and keep up with news in the sciences is to read New Scientist magazine. Although it is British, there really isn't an American equivalent and the magazine has become much more international over the last few years. It really isn't that expensive to subscribe especially since it is a weekly magazine but you can also read many of the articles on their website (or in the library copy of course). Although they do have a few longer articles each week, much of the magazine consists of brief news reports on recent research.

Here are a few of the evolution related articles they have published recently:

Gut parasites came from the deep: A genetic comparison finds links between bacteria from deep-sea vents and those from the human body. 7 July 2007

When giant penguins roamed the tropics: Millions of years ago, human-sized penguins roamed the Peruvian coast just 14 degrees south of the equator, according to new fossil evidence. 25th June 2007

Cooler climes help spur on evolution: Tropical hotspots of biodiversity are not the hottest as far as evolution is concerned. 23 March 2007

Looking for larvae in ancestral genes: Did our earliest animal ancestors go through a larval stage, or did that evolve later? 26 January 2007

and one from last year, illustrating the tendency of New Scientist to try and bridge the gap between more popular journalism and science writing. I'm guessing the original research report did not have this title - Mums help chicks if dad was ugly: Females appear to invest extra energy into getting their poorer-quality offspring off to a good start, at least among house finches. 29 September 2006
(I just checked, the title of the research article is: Yolk Antioxidants Vary with Male Attractiveness and Female Condition in the House Finch (Carpodacus mexicanus))

This time last year: Darwin's Finches

Giant demon duck of doom

A few years ago scientists in Australia described a particularly large example of a Thunder Bird, an extinct group of large (up to 3m tall and 500kg), carnivorous birds. For many years it was assumed these birds were related to other large flightless birds, such as emus, cassowaries and ostriches. However as further specimens accumulated opinions changed and it is now thought that the similarities between these groups are the result of similar adaptations following the loss of flight. The latest idea is that thunder birds actually evolved early in the lineage that includes waterfowl. Because of its large size, carnivorous habits and its waterfowl ancestry, the Australian find was nicknamed the 'Demon Duck of Doom.' Which, of course, guaranteed a bumper crop of press reports.

Now, from the same site, paleontologists are reporting flesh eating 'Killer Kangaroos' with wolf like fangs. Only a week old the story has already been picked up by a number of media sources. The message to paleontologists everywhere is clear - if you want some attention in the media find a carnivorous species from a group that is usually perceived as herbivorous. Bonus points if people already find the group funny. I'm off to look for a carnivorous cow.......

Web sight

At around the same time I was telling you about the coevolution of spiders and their prey scientists were reporting the discovery of the worlds oldest spider web. Preserved in a large blob of amber the web and the insects caught in it have now been dated to the early Cretaceous - about 110 million years ago.

Although the web is not complete enough for scientists to reconstruct it, enough remains to suggest this was not just a collection of strands and was probably in one plane like an orb web.

As you can imagine finding fossilized spider webs is unusual. We do know that fossilized spiders have had spinnerets for producing silk for closer to 400 million years.

There is a report on the research in New Scientist magazine.

The Thagomizer

As some of you have probably noticed I do like a good cartoon and I try to have a relevant cartoon to start every lecture. I was delighted to find out recently that Gary Larson (of Far Side fame) has inadvertently given paleontologists a new term. The original caption for the cartoon to the left was:

"Now this end is called the thagomizer, after the late Thag Simmons."

Apparently the collection of spikes on the tail of dinosaurs like Stegosaurus did not already have a name. So, in a nice nod to Gary Larson, the term 'Thagomizer' has been adopted as a genuine anatomical term, and has been used by multiple authorities, including the Smithsonian Institution.

Missing Links, Transitional forms and the Fishapod

Paleontology hit the headlines a couple of months ago when paleontologists discovered a fossil fish, Tiktaalik roseae, that showed the beginnings of digits, wrists, elbows and shoulders, as well as a skull, neck and ribs that resemble those of tetrapods like today's familiar four-legged land animals. Paleontologists suggest that it was an intermediate form between fish which lived about 385 million years ago, and early tetrapods which lived about 365 million years ago. Its mixture of fish and tetrapod characteristics led one of its discoverers, Neil Shubin, to characterize Tiktaalik as a "fishapod". Like any self-respecting Fossil Tiktaalik has its own homepage.

The story raised some interesting debate about what is meant by the term 'missing link' - a term that sees more use in the mainstream media than the scientific literature. A better term would be 'transitional form'. The Wikipedia article on Transitional Forms has a nice set of figures showing the number of Hominin species known to science in 1850, 1900, 1950 and 2002 - illustrating how our knowledge has steadily increased and although there are still 'gaps' in the record these gaps become smaller and smaller through time.

A popular term to designate transitional forms with is 'the missing link'. The term is especially used in the regular media, but is inaccurate and confusing. This is partly because it implies that there was a single link missing to complete the picture, which now has been discovered. In reality, the continuing discovery of more and more transitional fossils is further adding to our knowledge of evolutionary transitions.

The politics of Mastodon

Welcome to the Bio1blog.

All the material provided here will be supplemental to that provided in class. I will use this venue to provide some more in depth information, to provide links to research papers and other items of interest. Important notices about the class will always be posted on the main Bio1B website.

If you read any foreign press it is easy to find out what the rest of the world thinks of America. Whether people love America or, let's just say, 'less-than-love' America, I think the one thing they would all agree on is that America, as a nation, has no small amount of self esteem.

So it is perhaps surpising to look back a couple of hundred years, to the period shortly after the American Revolution, when the world had a very different opinion of America.

From the Wikipedia entry on the French naturalist Comte de Buffon:
'Besides his many brilliant insights he is also known for expounding the theory that nature in the New World was inferior to that of Eurasia. He argued that the Americas were lacking in large and powerful creatures, and that even the people were far less virile than their European counter parts. He ascribed this to the marsh odours and dense forests of the continent.'

In this context the discovery of a Mastodon near Newburgh, N.Y. in 1801 had both scientific and political implications. Although this was not the first Mastodon to be discovered in America this one was excavated by Charles Willson Peale and his son Rembrandt (who did the drawing above) who were friends with Thomas Jefferson.

From the Treasures of the American Philosophical Society entry on Peale's Mastodon.
'The mastodon was proof that America could and would sustain large and vigorous life forms, perhaps even larger and more vigorous than Europe. Best of all, it was clear that the mastodon was unique to North America, a symbol of the antiquity of our continent and exemplar of the new nation. Jefferson may well have had the Peales' mastodon in mind when he enjoined Lewis and Clark to scour the western landscape for mastodons, living or dead.'