Maybe the Vex themselves brought it?

I was going to say that, too. What evidence do we have that the Vex are NOT gardeners? Everyone needs a hobby.

Maybe the Vex themselves brought it? A culture that grows its bismuth-like computers and were (are?) the caretakers of the Black Garden, they seem to have a high interest in horticulture. (I also find it interesting that Mercury and Venus were both made into garden worlds before the conversion process began. If Mars was a garden world before the Darkness came, it would fully qualify in that trend, too.)

Do paleodeserts count? They're basically sand dunes that have been stabilized by vegetation. A portion of Nebraska (my sympathies to anybody who lives there) is composed of these, known as "sandhills." After all, one would be hard-pressed to think of this as a sand dune, but...

I'll avoid the technicalities of Earth (Terra, Bob, whatever you want to call it) after its impact with a Mars-sized body, because that's just splitting hairs.

Edit: I've tried editing it twice now, and the previews won't let it work. Wikipedia and the forums hate me.

Fix'd. the issue was with the link itself, not your HL. Or we could just have the image:

Found the land of the Windows desktop... Anyway, I suppose it can count, yes, assuming that region was purely arid sand, and not mixed with soils of any sort. But again, the area within the Vault is completely isolated by extreme degrees. If only we could get that back door open during a trip to the past/future, maybe we'd get a better idea of how vegetation could have somehow found its way into the Vault...

I'll avoid the technicalities of Earth (Terra, Bob, whatever you want to call it) after its impact with a Mars-sized body, because that's just splitting hairs.

Edit: I've tried editing it twice now, and the previews won't let it work. Wikipedia and the forums hate me.

Th past is the dusty, brown one.

The Future is the lush jungle, which presumably formed after Traveller's terraformation of venus.

That's backwards. The brown one is the future, hence the 'Descendant' Vex. The green one is the past, hence the 'Precursor' Vex.

As for the designs, I think the white and gold Vex are the newer design because they're all shiny. It's simple reasoning but the best designs only need simple reasoning. Knowing Bungie though, I could almost think they switched them around (multiple times) on purpose to create an out-of-game confusion that reinforces how transcendent and inscrutable the Vex are.

The 'older' ones remind me of bronze-age ... stuff, maybe even steampunk, where as the silver/white and gold gives me a more sci-fi feel.

"Left" and "Right" it is!

Which brings it back around to the original problem-- I can never remember which area goes with which side! Half the time I'm half blind when I stumble out of the gate, and every time I follow the relic-holder to the center or wherever they're going to get cleansed and protected by the relic.
As for the designs, I think the white and gold Vex are the newer design because they're all shiny. It's simple reasoning but the best designs only need simple reasoning. Knowing Bungie though, I could almost think they switched them around (multiple times) on purpose to create an out-of-game confusion that reinforces how transcendent and inscrutable the Vex are.

Sand sand I can't recall off the top of my head, but if dry earth counts, the Amazon Forest itself used to be a dry savanna before what it currently is, for instance.

Doesn't count. The surface (or rather, the elevated platform) of the Vault is sand sand, and on top of that, it's isolated, and far from any fertile land or moisture (the bubbling springs and streams aside.heck, the entire present-day descent into the Vault has almost no vegetation whatsoever.

Like I said, a Tundra (or on the other end of the climate spectrum, a Savanna) doesn't count, since it's not arid soil. It can become fertile if vegetation creeps in from an outside source. Either way, between the lack of light sources and giant pits, any vegetation somehow reaching the Gatekeeper area is extremely unlikely and on top of that, replacing the sandy, arid platform with enough moisture and soil to grow into a jungle environment? Impossible, I say...

First batch was all shiny and gallant, because they had resources and a poetic sense of sorts. Last batch was streamlined to be functional and had no real shine because they were already all combat-focused.

Seems more likely for a moist jungle to become a desert than for a desert to become a moist Jungle in a realm presumably outside of the Traveler's reach...

Nah, either can happen and has happened on earth.

Any examples of reverse desertification? And Tundras don't count, I'm talking sand...

I don't know who's right anymore regarding past and future. Given the images I've seen in this thread, maybe Bungie is confused, too.

Heh, this conversation is making me think of that cyclic universe discussion. One cycle's future is another cycle's past, who knows when anyone is...

"Left" and "Right" it is!

I finally started using left and right. In a pinch I say brown or green.

I don't know who's right anymore regarding past and future. Given the images I've seen in this thread, maybe Bungie is confused, too.

Seems more likely for a moist jungle to become a desert than for a desert to become a moist Jungle in a realm presumably outside of the Traveler's reach...

Nah, either can happen and has happened on earth.

Th past is the dusty, brown one.

The Future is the lush jungle, which presumably formed after Traveller's terraformation of venus.

Not necessarily. Who's to say it wasn't lush and green billions of years in the past? (Didn't Ghost say something to that effect about the Vault entrance?)

Seems more likely for a moist jungle to become a desert than for a desert to become a moist Jungle in a realm presumably outside of the Traveler's reach...

The portals all lead to the very same room at different points in time. Does anything change within to imply the passage of time? One stone out of place could be enough to tell...

Th past is the dusty, brown one.

The Future is the lush jungle, which presumably formed after Traveller's terraformation of venus.

Now see, that's what I used to think, but then I was corrected. So the precursors are on the brown one and the descendants are on the green one? I thought it was the reverse.

The Grimoire on Bnet, as I said, shows this...

Then again, according to the "Precursor" card:

"It would be easy to assume these Vex are the ancestors of those we face today - but with the Vex it is never so simple."