Burrowing Things

 

Burrowing Owl at Cesar Chavez Park, February 2011

The oldest form of life on Earth has survived all the great extinction events and is an important part of not just "the ecosystem," but even of the internal microbiome of the likes of owls and humans. Bacteria have ruled the planet for around 3.5 billion years, and all us plants, fungi, and animals had to emerge and evolve in their royal presence. "[T]he cell biology and genomes of all modern eukaryotes were built on a bacterial foundation."

An evolution in bacteria was responsible for the Earth's first great extinction event, which doesn't even count in the so-called five great extinctions, and which made life possible for us eukaryotes. Interestingly, the five extinctions that do count were all a result of rapid climate changes that involved either planetary cooling or warming. 

The earliest of the big five occurred 444 million years ago. But that first pre-big-5 extinction occurred around 2.5 billion years ago and is known as the Great Oxidation Event. It was brought on by the proliferation of photosynthesizing cyanobacteria that produced a deadly gas: oxygen. The bacteria that had been basking blissfully in a warm methane atmosphere for a billion years were unceremoniously torched by this new, highly reactive gas.

As I was thinking about all this it occurred to me that our own ancestral gut microbiomes, most of which are composed of obligate anaerobic bacteria, are pretty good sanctuaries from inflammatory oxygen. Somehow the anaerobes that survived the deadly new Oxygen World burrowed into whatever new forms of life came along that could take advantage of oxygen's power. Now here we are, with each milliliter of our large intestines providing a home to 100 billion microbes of perhaps 400 species.

All us animals, including birds, live with symbiotic microorganisms in our guts, where the tiny critters provide "a multitude of nutritional, defensive, and developmental functions with a myriad of implications for host health and fitness." 

We are dependent on minerals and gases, on liquid water, on microorganisms, and on the plants and animals we consume to power our lives. If you think about it, we truly are one with everything. 

Owl on the Shoreline

Owl in the Spotlight

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Virga Bow

 

Virga Bow at Sundown

The last couple of times I've gone over to Grandview Park to look for a rainbow, all I got was rained on. It's only at unexpected times that I actually see one, including this "virga bow" I stumbled upon when I looked out my rear, east-facing, window shortly before sundown yesterday. Although I'd been somewhat rained on during a bike ride earlier in the day, it appeared that no rain was actually reaching the ground when this bow appeared. 

There wasn't enough daylight left to run a timelapse, and I only fired off four frames before the sunset color drained out of the clouds and the bow broke up.

Since I'm already posting something, I might as well toss in a few phone snaps I shot during my walk and bike ride yesterday. My daily walk down Noriega Street takes me right past the scene of the 22nd Avenue house explosion, which happened the day I biked to Mt. Tam. It happened right around the time of morning that I'm usually walking by there. People heard or felt the blast from many blocks around.

Garden Plum Blossoms

Cordoned Block at 22nd & Noriega

Rehabilitation of Golden Gate Park's Middle Lake

Magnolia Along Chain of Lakes Drive

Young Herring Gull (?) at the Esplanade with Cloud-Hidden Mt. Tamalpais

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Tam Cam

 

Big Buck Passing Through

I figured it was fairly well established that this location has lots of deer and turkeys, so I moved the cams to a new location yesterday. I locked my bike to a tree and hustled up the ravine, only to soon realize I was in the wrong place. It looked like a pretty good alternative location, though, and I will keep it in mind for the future. 

In the meantime I wanted to find someplace a little different, and one of the new spots I found seemed promising, with lots of bobcat scat around. As usual I would be extremely surprised if any humans showed up in either of the new spots, but I was not surprised to find someone's long-lost Aerobie Ring Flyer. You can chuck those things a mile (well, not quite a mile).

Wild Turkeys Among New Spring Growth of Hounds Tongue

Tam Cam Clips

On the way home I saw this gigantic, brand-new-looking ship passing under the Golden Gate Bridge, so I pulled over and grabbed my phone to get a selfie with it. I took note of the ship's name on the stern but mis-remembered it. I thought it was Polar Explorer. It seemed so new, I thought it was one of those NOAA research vessels that sometimes tie up behind the Exploratorium. However, this ship seemed headed toward the Richmond refineries. Sure enough, I took note of the Chevron logo on the superstructure once I got home and saw the photo. It's actually an oil tanker, the Polar Voyager. It looks so spanking new because it was built in 2014.

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