Red Rock Canyon

While we were in Las Vegas, Simiao and I decided to go hiking at Red Rock Canyon.  I've always found deserts quite beautiful, and the scrambling at the Calico Hills was some of the best I've ever experienced.  There was one thing we found, however, that I thought was super-interesting!

As we were scrambling down through the canyon at the Calico Hills, we were climbing past some Sonoran Scrub Oak.  As I glanced over, I noticed an odd, round, red and yellow berry growing on the oak next to me.  It was very pretty, so reached over and plucked it.  I said to Simiao, "Hey, look at this weird seed!"  I handed it to her.  She mentioned that it felt hollow, and I speculated that it might be designed to break off and float when the rains fill the canyon.  I carefully set it down on a rock and split it in half with my heel, and this is what we found:

A gall from a Sonoran Scrub Oak

Satisfied that it was the seed of a scrub oak, I resolved to look it up when I got home and determine what the evolutionary purpose of this egg-like seed containing what appeared to be a dandelion-like puffball to be carried by the wind was.

Little did I know that it would take quite a few hours of research to determine the truth of this "berry".  This is not the seed of a scrub oak.  Scrub oaks produce acorns, but there was no question that this strange ball was connected to the oak itself--a small stem was visible.  In fact, this is called a "gall", and it can be formed when a gall wasp larva reprograms the cells in the oak itself so that the oak forms this tumor-like growth which in turn acts as a food source and habitat for the developing wasp.

There are hundreds of species of gall wasp, and I cannot say which might have produced this wonderful structure.  It is, however, a marvel of evolution that these wasps have come to manipulate the development of a plant into a completely different manner of growth!

With the right person, adventure is always closer than it appears!