[I know I already posted this, but the video of the trailer had to be taken down, fixed, and put back up, so I'm reposting to give everyone a chance to actually watch it. Everything works now. Yay! Also, it's up on reddit (actually twice) and Fark, too.]

Finally, at last, after many months, I can now officially reveal the Sooper Sekrit Project that has kept me so busy over all this time. I think you’re gonna like this… so why not just jump right in to the teaser trailer posted online by a small TV network you may have heard of called THE DISCOVERY CHANNEL!

[evil laugh]

How ’bout that?

I’ve been working with the Discovery Channel on hosting a new TV science show called "Phil Plait’s Bad Universe". It’s a three-part program where I dissect issues in astronomy and science, putting claims to the test. There’s no air date yet, but I’m hoping it’ll be on your TV sets this fall.

As you can see in the trailer, the first episode is about asteroid impacts, and we tackle the issue in a way that I don’t think has been done on TV. I get right into the mix, blowing things up, flying in a jet, going where the action is so that I can participate in experiments with scientists and try to find out what works and what doesn’t. The idea here is not to have some dry, narrated documentary. Instead I will show you what’s going on, take you along, so that you can see how these things work and what we’re doing to investigate these issues.

I’ve been having a tremendous time filming this, flying around the country, seeing things I ordinarily would never get to see. And the beauty is, you can come too!

Eventually I’ll post some pictures I’ve taken on this adventure, and we’ll be posting more video online as well as more information about the show soon. I’d like to thank everyone at Discovery Channel and Morningstar Entertainment for giving me this chance to fulfill a long-standing dream of mine. We’ve worked very hard on this program, and I hope you like it.

Yay!

Jellyfish may seem like simple blobs but some have surprisingly sophisticated features, including eyes. These are often just light-sensitive pits but species like the root-arm medusa have complex ‘camera’ eyes, with a lens that focuses light onto a retina. Not only are these organs superficially similar to ours, they’re also constructed from the same genetic building blocks.

Hiroshi Suga from the University of Basel has been studying the eyes of the root-arm medusa (Cladonema radiatum). His work strongly suggests that all animal eyes share a common origin, whether they belong to a human or an insect, an octopus or a jellyfish. The details may be different but they’re all under the control of closely related ‘master genes’ that themselves evolved from a common ancestor.

As you might imagine, growing an eye is a complicated business and involves a huge alliance of different genes, switching on and off in a coordinated way. But in humans and other animals, this alliance all comes under the control of a master gene called Pax-6. Pax-6 was discovered in 1994 by Walter Gehring, who also led the current Cladonema study. Faulty copies can cause serious eye problems in animals as diverse as flies and rodents. And activating the gene in the wrong part of the body can produce eyes where they really shouldn’t exist, like the leg of a fly.

Pax-6 is so important that it’s largely the same in very distantly related animals (the technical term is ‘conserved’). You can take the version of Pax-6 from a mouse and shove it into a fly, and it will still be able to trigger the development of an eye. Even though these misplaced eyes have been activated by a mouse gene, they have the compound structure of typical fly eyes. This underlies the role of Pax-6 as a conductor – its job is to coordinate an orchestra of other eye-producing genes.

Pax-6 is just one of a number of closely related Pax genes. Cladonema doesn’t have a direct equivalent of Pax-6 but it does have three Pax genes of its own, each belonging to a distinct lineage. Only one of these – Pax-A – is actually active in the eyes and Suga clearly showed it’s the jellyfish’s master eye gene. When he transferred it into a fruit fly, he managed to trigger the development of eyes on odd body parts.

Cladonema isn’t the only jellyfish with complex eyes. Another one called Tripedelia belongs to a different group of jellies altogether and it too has a master eye gene called Pax-B, which belongs to a different group to either Pax-A or Pax-6. These three groups of genes evolved shortly after the very dawn of animal evolution from a single ancestral gene that duplicated itself several times. Its copies diverged into the different Pax groups.

So three groups of animals build their eyes using related master eye genes: the hydrozoan jellyfish, represented by Cladonema, use Pax-A; the cubozoan jellies, represented by Tripedelia, use Pax-B; and the bilaterians, including humans and the vast majority of other animals, use Pax-6.

You could argue that this means animal eyes evolved independently at least three times. But Suga disagrees – if this was the case, you might expect the master genes to be recruited from different gene families. As it is, they’re all Pax genes. Instead, Suga thinks that the building blocks of all animal eyes share a common origin. It’s a view that runs counter to the common assertion that animal eyes evolved many times independently but it’s one that Gehring has been championing for years.

When the common ancestor of jellyfish and more complex animals initially evolved eyes, Suga thinks they were under the control of several different Pax genes from the various families. As the bilaterians, hydrozoans and cubozoans diverged from one another, their eye programs eventually fell under the control of single Pax genes from different families. This shared origin explains why genes from one Pax group can still perform the role of genes from the others, and why Cladonema’s Pax-A can produce eyes in a fly.

The evolution of Pax genes. 1) An ancestral gene duplicates itself to produce different classes of Pax genes. 2) The ancestral animal eye evolves under the control of several different classes of Pax genes. 3) In three different animal groups, the Hydrozoa and Cubozoa (both jellyfish) and the Bilateria, eye development comes under the control of species Pax genes. 4) Some of the Pax genes in Bilaterians have been altered.

Reference: PNAS http://dx.doi.org/10.1073/pnas.1008389107

More on eye evolution:

• Mantis shrimp eyes outclass DVD players, inspire new technology
• Glowing squid use bacterial flashlights that double as an extra pair of “eyes”
• From day to night – a lesson in eye evolution with the owl monkey
• Nocturnal mammals see in dark by turning displaced DNA into lenses
• Spookfish eye uses mirrors instead of a lens
• ‘Missing link’ flatfish has eye that’s moved halfway across its head
• Jellyfish and human eyes assembled using similar genetic building blocks

If the citation link isn’t working, read why here

Alright!  Now we get to discuss neutrinos without me having to worry about being reduced to my component parts.  And while I think my component parts are lovely, I’m sure you would rather not go there.

Neutrinos are interesting little guys, meaning literally “neutral elementary particle”.  An elementary particle is simply something which is not known to have smaller parts.  We used to believe atoms were the smallest possible units of mass.  Now we know, of course, that “atoms” are whopping HUGE units of mass.

No, it's not "cute" - This was the first ever hydrogen bubble chamber to detect neutrinos

When we start talking about “elementary particles”, you’re really talking about particle physics.  You quickly get into leptons, bosons, positrons, muons, tau neutrinos, and lots of other really cool words you swore in freshman algebra you’d never use.

Guess again.

Particle physics is also where String Theory comes in, but we aren’t playing around in THAT sandbox today.

Okay… here’s the very basics.  You can accept that everything is composed of small parts, right?  I mean, c’mon guys.  You swallowed atomic theory without gagging, right?  You’re just going to have to realize that an atom is the apple, and it can be sliced and diced into all kinds of little parts and pieces.  Some of these parts have a positive charge, some a negative charge, and some are neutral.  Still with me?

You just never realized how very many pieces and parts atoms could be sliced into.

Really, you’re more than half-way there.  You have the concept of atoms down, right?  You have the whole negative/positive/neutral thing going, right?

We’ll leave string theory for another day.