25 years of bacterial evolution

Richard Lenski has been running a long term experiment on the evolution of e. coli. This experiment has been running since 1988, and reached 50,000 generations in 2010. That’s about a generation every 231 minutes (thank you Wolfram Alpha). Over this time, they found a number of interesting evolutionary mutations.

All of the populations evolved to have larger cells than the ancestor population. Four populations lost the ability to repair damage to DNA, leading to more mutations. One group evolved an adaptation to grow on citrate.

It is important to remember that evolution is a process. Evolution doesn’t stop, and we aren’t the end result of evolution. All other species are also evolving. Evolution will continue for all species, including Homo sapiens.

First forecast earthquake

On 5 September 2013 a magnitude 7.9 earthquake rocked Costa Rica. The unusual thing is that scientists were able to forecast this one. They knew that a 7.7 to 7.8 quake would occur in this area in 2000 ± 20 years. It turns out that large (> 7 magnitude) earthquakes happen on this peninsula about every 50 years. The subduction zone also is on land instead of in the ocean, so it’s much easier to study.

They started studying in 1990 using GPS stations to measure the Earth’s movement. This let geologists identify two places where the plates were locked and building up stress. Knowing this, they were able to make civil changes to improve building codes and warn the populace on what to do when a quake struck.

But forecasting is different than predicting. Predicting the actual date of an earthquake is pretty much impossible.

Oil from algae?

A new technology can create crude oil in under an hour from algae. While there are already techniques to do this, they are expensive and slow, requiring drying the algae before turning it into oil. This new technique uses wet algae, so it is faster, and doesn’t use as much energy.

If this can be scaled up, then it solves one of the two main problems with oil synthesis from algae. The other is growing enough algae in the first place. Scientists are working on that problem.

Because algae uses carbon dioxide from the air, this method would be carbon neutral, or possibly even carbon negative because not all the carbon gets burned. Carbon that isn’t burned can be used in plastics, and that would be kind of like carbon sequestration.

Yes, there are many other problems that need to be worked out before this is close to feasible. But I like that the research is being done on methods like this. I’d like it even better if we can have a system that doesn’t have emissive pollutants.

High school chorus


The high school chorus came to school today and sang some numbers. It was great to see some of my previous students again. We’re the smallest sending district of four to the regional high school, and three of my previous students were featured! Cool!

It’s about time

We’re finally back to the moon. The Chinese have sent a lander to the moon. Congratulations! I’m glad we’re back; I just wish it hadn’t taken so long.

At 8:11 AM EST, the Chinese moon lander Chang’e 3 and rover soft landed on the moon in the Bay of Rainbows map here. This is the first soft landing in 37 years. Chang’e 3’s solar panels have been deployed, and soon the Yutu rover will roll out.

Also, on this date back in 1972, Gene Cernan left the last footprints on the moon from Apollo 17. And, back in 1546, Tycho Brahe was born.

Impossibly distant planet

Not impossibly distant from us, but from the host star. HD 106906 b is in the constellation Crux. The planet orbits at a distance of 650 AU, or 97 billion kilometers (more than 20 times the distance from the Sun to Neptune, and is 11 times more massive than Jupiter. The system is thought to be only 13 million years old, very young. Our current theory of how solar systems form will have to change because of this discovery. A planet should not be able to form that far away from the star. If it is a binary star instead of a planet, then it isn’t massive enough. Our understanding of binary stars is that the stars should have relatively close masses, about 10:1. This is over 100:1.

There is a petition to name the planet Gallifrey, after the home world of Doctor Who, but the IAU doesn’t accept popular names for exoplanets.

Observation today


Today was my observation. I knew that I would be observed sometime this month, and Dr. DiGanci came in at the start of 2nd period. The kids were great, and I couldn’t have asked for a better class for it. We talked about forestry, clear cutting, and selected cutting. At the end of class Dr. DiGanci said that he enjoyed the class and learned a few things.

Staph bacteria subverts the immune system

An article in Science Life explains how one of the persistent staph varieties manages to defend against the host’s immune systems. Staphylococcus aureus is a nasty bug that about 20% of people frequently have. A mutation in two genes allow the bacteria to cause the immune systems NETs to create a chemical that kills macrophages, white blood cells that would normally kill the bacteria. A very devious system.

Now that we know this, scientists can use this information to develop therapies that can fight against it. This will greatly help against methicillin-resistant S. aureus (MRSA), which is antibiotic resistant.