Cutting Edge techniques to do Ancient Science

Now they've sequenced the woolly mammoth! How awesome is that?! Not only have they sequenced about 80% of its genome, but they've discerned that they're very closely related to modern elephants (already suspected, of course), and they may have an idea as to why they went extinct!

Just amazing stuff you can tell from a DNA sequence. They were able to get a sample of mammoth DNA from hair of the mammoth. There are some amazingly preserved specimens of the mammoth discovered over the years. Some specimens were so well preserved in ice that the meat is still edible (no word on if it tastes like chicken).

But an analysis of the DNA sequence led by Stephan Schuster lab at Penn State University with Webb Miller as primary author and published in Nature showed that elephants and mammoths are very closely related at a genetic level with a difference of 0.6%, half that of humans and chimpanzees. Furthermore, at an estimated 4.7 billion base pairs, it's 1.4 times the size of the human genome.

They sequenced genomes from several specimens of woolly mammoth and discovered that there was indication of inbreeding among mammoth populations, and not a great deal of genetic diversity. For a species, this is bad news. It means that the entire population is susceptible to being wiped out by disease or climate changes. It could indicate why the mammoth went extinct--simply because there wasn't enough to choose from in the pool of genes within the mammoth population to create individuals who could combat environmental or health stresses.

Nature will charge for access to the article, but you can read a description about it here

The Sounds of Space

I've been too busy to post much lately, if anyone has noticed. But I heard this story recently on NPR that was just so cool that I had to share it.

Here's the link to the audio of the story.

Two scientists, one from Britain and one from Romania, asked the question, what do things sound like in space? We know what outer space looks like, but do things sound differently out there than here. This is a valid question because lots of atmospheric factors influence acoustics and sound--humidity and carbon dioxide concentration are examples. So, they put various parameters into a computer to try to simulate the atmospheres on Mars, Venus, and on Titan, one of the moons of Saturn. All three of these contain atmospheres. Then they played a Bach organ piece in each of those environments.

They sound different in each one! Not hugely different, but different enough to tell. Then they put each on top of each other and played a solar system symphony with contributions from Earth, Mars, Venus, and Titan. Wow was it dissonant!

So, while there is music in the spheres, it's not always harmonious.

The Ancient Redwoods in the Pouring Rain

I went to Muir Woods this weekend to walk among the ancient growth redwoods in the pouring rain. There weren’t many people there braving the elements (or actually just one element to brave here—the water), so we had the place pretty much to ourselves. It was mid-afternoon, but dark as the clouds and the tree canopy stole much of the available light. The colors were intense, as the ground cover ferns soaked up their first substantial water in months. The small stream that runs through Muir Woods, practically dry 2 months ago when I was last there was running fast over the rocks and ledges and providing a place for the fish that live there to grow and thrive.

This place is old growth redwoods. It’s been a National Park since the early 1900’s, and the trees that grow there vary in age, with the oldest being close to 1000 years. I like to walk through there and think of the world when those trees were seedlings and how much things have changed in the interim---and how much they’ve stayed the same.

Nature and science exist all the time. We just discover it along the way.