Monthly Science Roundup #1

September came and went, and I never had a chance to sit down and do any weekly roundups! But I didn't want to just ignore all science news from the past 30 days, so I've decided to post my first ever "monthly" roundup, with four of the biggest science news stories September had to offer.

1. Evolutionary History Rewritten?

Generic Placoderm anatomy.

"Every now and then you are confronted with jaw-dropping specimens like Lucy the Australopithecus (an extinct, upright-walking hominid) or the first batch of Chinese feathered dinosaur, unleashing a flood of new information that greatly clarifies our view of the distant past and often forces us to rethink what we thought we knew about evolution. A little fish called Entelognathus now joins the ranks of these exceptional fossil discoveries." - Dr. Brian Choo, Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing

So this happened. It's a very cool find, though it's going to need more scrutiny before we overthrow what we've previously thought of our evolution. Here's what was presented and proposed (and make no mistake, I am geeking out about this):

Classically, we say that the fish-to-land transition animals were descendents of shark-like cartilaginous fish, who eventually developed a strong enough skeleton to handle life out of water. But a new discovery shows that a group of early fish known as "placoderms" (famed for their outwardly bony armor), actually had three specific types of bones that were thought only to be found in the bony group of fish that scampered out of the water much later on. Cartilaginous fish do not have these bones. Therefore, the ancestor to cartilaginous fish and the bonier air-breathing, scampering variety, was actually a member of the placoderm family. Follow that?

Take-home message: Bony skeletons were the ancestral state. Not cartilage. Cartilaginous fish LOST their bones.

This is a really big deal. Textbook-rewriting-big. The order of skeletal development in evolution has just been turned on its head. If it holds up. (I hope it does. It's kind of awesome.)


2. Water on Mars

Okay, maybe this doesn't sound like news. We've known about water on Mars for a while, right? Well, this time we're learning about water via the first ever chemical soil sample analysis from Curiosity! Especially since it involved using X-ray diffraction, which was long thought to be impossible to miniaturize enough to put on any sort of rover. Obviously, they managed it with Curiosity.

So what's the buzz? Turns out, there's a whopping 2% of water in one scooped up sample of dirt, which sounds like great news for rocket fuel farming. However, they also found a lot of perchlorate in the same sample, which is toxic to rocket fuel, and would make harvesting this water for that purpose rather difficult. Somewhat more interesting, is that it is likely both of these substances are only in the dirt because they're being absorbed from the thin Martian atmosphere.

There was a lot of media hype about finding water in this sample, but don't let that fool you. Mars is a hostile environment. Utilizing this water would not be a walk in the park. The bigger story here is the methods used to detect these things. I'm excited to see what else Curiosity finds with its fancy equipment.


3. Oxygen in Our Atmospher Earlier Than Thought

Banded Iron Formation. A geological early indicator of oxidation.

Based on geology, the usual accepted date for the first appearance of oxygen (in any serious quantity) in Earth's atmosphere was about 2.6 billion years ago. But researchers recently drilled into 3 billion year-old rock, and unexpectedly stumbled upon signs of oxidation from way back then!

Whoa. So what's going on? Oxygen has been hypothesized to have entered the atmosphere when photosynthesis developed in cyanobacteria. So this means either photosynthesis developed in cyanobacteria hundreds of millions of years earlier than though, or photosynthesis developed in something else way earlier, or there's another way of getting oxygen into the atmosphere in massive quantities that no one has thought of yet.

This is going to open up a slew of debate, and I'm anxious to follow along and figure this out with the scientists.


4. THEY'VE BUILT LIGHTSABERS

Okay, so not really. BUT THEY COULD.

Researchers at MIT have taken photons and gotten them to smush up together to form molecule-like structures. A serious feat, since photons have generally been thought not to have any real mass or interact with each other at all.

So what these interacting photons are doing is binding together and creating their own type of mass by pushing against one another. Essentially what theoretically happens in lightsabers. Because Star Wars is real and 9 year-old me is cheering louder than the Ewoks after the second Death Star explosion.

This was discovered when researchers sent photons into a super-cooled atom cloud. Because of atomic properties, nearby atoms can't be in the same level of excited state simultaneously. So photons exciting atoms end up pushing each other along so that the first photon moves on while the second excites a different atom. This energy transfers from atom to atom as they move. But this whole process slows the photons, so they end up leaving the cloud together, as a sort of "molecule".

And if we can make photon "molecules", we someday might be able to build entire photon structures. BUILD THINGS OUT OF LIGHT. LIKE LIGHTSABERS. AND MY LIFE WOULD BE COMPLETE.

Okay I'm done now.

Really. That was September.