Wait a minute you might be saying. How can evolution be a "breakthrough"? Didn't Darwin come up with the idea 150 or so years ago?
Questions like these make some people think evolution was chosen in response to the ongoing Intelligent Design debate.
The idea of evolution isn't the breakthrough. Evolution is an established science that forms the foundation for all of modern biology.
But the editors of the journal Science
felt that some of the research done in evolution this year was pretty amazing stuff.
The editors liked three evolutionary results in particular:
1) Figuring out every letter of a chimpanzee's DNA
2) Gathering more evidence that species can evolve when not separated geographically
3) Resurrecting the 1918 flu virus and figuring out why it was so nasty
I'll go over each one of these in a bit of detail below and explain why the editors thought these results were such a big deal.
1. What makes us human?
The first big finding was the sequencing of the chimpanzee genome. We now know all 3 billion letters of a chimp's DNA. This is important for a couple of reasons.
First off, by comparing human and chimp DNA, we may be able to figure out what, at the DNA level, makes a human a human. Because humans and chimps separated so recently, we share a lot in common.
In fact, we are either 96% or 99% the same, depending what you look at. So this should be easy, right? Just look at the 1-4% difference and use that to figure out why we're human.
This isn't as easy as it sounds. First off, 1% doesn't sound like much but it is around 30 million differences. This is a lot to sort through, especially when a lot of these changes don't matter.
Lots of differences won't distinguish between a chimp and a human. Some of them will just be differences that distinguish one human from another. We humans only share 99.9% of our DNA with each other, for example.
What this means is that at the very least, 0.1% of the difference isn't important for distinguishing us from chimps. That 0.1% is important for distinguishing you from me.
And there are lots of changes that don't matter as well. So scientists will need to pick out the changes that distinguish a chimp from a human. It probably can be done but will be a huge task by itself.
In the meantime, we can use the chimp genome for simpler but still very important tasks. For example, chimps aren't infected by HIV but we are. Scientists are working on finding out why this is at the DNA level. From this they might be able to make new medicines to treat the disease.
Chimps also don't get malaria. Or heart disease. Or chronic viral infections in their livers. By comparing human and chimp DNA, we will be able to figure out why this is. And maybe make medicines to cure malaria, prevent heart attacks, etc
Very important stuff, but a breakthrough? Depends on what you think is a breakthrough.
All of these letters are really just a tool to answer these other questions. A very powerful tool that was a lot of work to generate but still just a means to an end. Once they find out why HIV can't infect a chimp or why we can talk but chimps can't, then we'll have a breakthrough.