Wednesday search challenge (09/18/13): Who is my great-great-great-great-great-great-great advisor?

Before we begin....  a minor admission.  A mini-mea culpa, if you will.  
Obviously, I was off on vacation in Bonaire last week.  It was a fabulous trip.  If you're really curious about Caribbean diving, here's a link to my G+ Bonaire photo album.  

So I'd planned on finishing up the "parrotfish sand problem" last week, but got too busy diving.  (And, truthfully, I spent much of my time on the last two days chasing after parrotfish, hoping to catch them in the "sand creation" act.  I did, but it was hard!)  

Then, the moment I got back, I was plunged into the deep end of work.  So I haven't had any time to finish up the parrotfish question.  But I shall.  It just might be at the end of this week.   

Hang in there... more work on this in a bit.  

AND NOW... back to today's Search Research Challenge.... 

Because I'm time-limited, I'm going to post a fairly simple challenge.  Once you figure it out, it's fairly cool and interesting.  (But, as with many of these challenges, if you don't see the solution, it will look crazy-hard-impossible.  Remember what we've talked about before in this blog.  If you keep those search principles in mind, you should be able to figure it out.) 

A genealogical chart from the original King James bible (1611).  Image courtesy LOC.gov

Background: 

As you know, I got my PhD in Computer Science from the University of Rochester in 1985.  My specialty area was Artificial Intelligence (if you must know, my thesis title is "Schema-based Problem Solving").  

And, as you know, every doctoral student has one main advisor (or rarely, two...).  

There's also a very traditional aspect to getting a PhD.  Having a doctorate awarded is a relatively long, ritualized, ceremonial affair involving special gowns, hats, felt stripes on the arm of your cloak, and history.  

Most PhD students know their advisor's intellectual lineage.  That is, you know who your advisor's advisor was, and often the great-advisor, and so on.  There's a bit of legend and lore in all this; a feeling that excellent advisors pass their learned opinions down from the greats in the past.  And that observation leads to today's challenge.  


Challenge:  

Who is my (meaning me, Dan Russell's) great-great-great-great-great-great-great advisor?   (And why is that an incredibly cool thing to know?) 

In other words, I believe that you can figure out who my advisor's-advisor-advisor-advisor-advisor-advisor-advisor was (back 7 PhD generations).  Once you figure it out, it's a fairly interesting thing to know.  (Put it this way, I was certainly surprised.) 

Search on! 

Answer: What kind of fish?

Short answers:  

1. Fish?  Stoplight Parrotfish (Sparisoma viride). 

2.  Geology?  Parrotfish bite into the coral, scraping off a bit with each bite.  They digest the algae they get in that bite, then the coral bits are excreted into the water, making up a large amount of sand.  In essence, much of the white sand of Caribbean island beaches is made up of fish poop!  (Okay, the excreted, indigestable bits of pulverized coral.)  

Stoplight parrotfish (Sparisoma viride)

My solution:  As you can see from the comments, there are many paths to solving this.  I solved it by searching for: 

     [ Caribbean fish guide ] 

And finding ReefGuide.org which has a very high quality guide to the reef fishes of the world.  From their home page I chose "Caribbean, Bahamas, Florida" and then did a quick scan of the fish families.  It wasn't a "small oval" fish, or any of the other's I clicked, until I found the parrotfish category.  Once you see the parrotfish page, it's pretty clearly that kind of beast.  

ReefGuide.org's parrotfish categorization page

To find the geological effects of this fish... My first search (like many of you) was for 

     [ stoplight parrotfish geology ] 

but the results were too diffuse to be useful.  (Search question:  Why didn't I include the double quotes a la "stoplight parrotfish"?  Because I figured that bigram--stoplight then parrotfish would be pretty common only as a fish reference.  So I didn't bother.)  

So I modified my query to be:  

     [ parrotfish geology ] 

and quickly found many articles about the effect of parrotfish (in general, not just the Stoplight parrotfish) on sand creation in the Caribbean.  

Just to triangulate what I was reading, I did the same search on Scholar to see a few scholarly papers on the topic.  

One paper,  "Rate of bioerosion by Parrotfish in Barbados marine environments" (1) points out that "[stoplight parrotfish] were observed to spend 80% of their time feeding on surfaces covered with filamentous algae and 20% on sand. Only Sparisoma viride consistently leaves well-defined scars on live coral."

But there's a debate among different sources about how MUCH sand a parrotfish produces each year.  If you look at the comments, some say it's 1 ton (2,000 pounds) / year / fish, while others say it's 200 pounds / year / fish.  Since that's SUCH a variance, I'm going to let the crowd work on the rate of sand production / fish for a bit longer.  The mystery remains!  
3.  How MUCH sand does a single parrotfish create in a year?  

As noted in the comments, some male parrot fish keep harems of females nearby. When the dominant male dies, one of the females will change gender and color and become the alpha male for the harem.


There's also a striking difference in appearance between the adults and the juveniles. Here's a photo I took yesterday of a juvenile Stoplight parrotfish. 

Stoplight parrotfish,  juvenile (Sparisoma viride)

Tomorrow I'll comment more on the "sand production" question, but give it a shot. It's a genuine difference of data question.  Since they vary by a factor of 10, one estimate should be clearly very wrong!  

Back to vacation!  Nice job everyone.  

And... just for Remmij, who asked for a picture of the Hilma Hooker, here's one shot of one our buddies entering the wreck through a hatch opening (it was on the top, but the wreck is laid over on its side, so this is now on the side of the wreck...)   

Entering the Hilma Hooker wreck at 80 feet.

----- 
(1) Frydl, Paul, and Colin W. Stearn. "Rate of bioerosion by parrotfish in Barbados reef environments." Journal of Sedimentary Research 48.4 (1978): 1149-1157.

Wednesday search challenge (9/11/13): What kind of fish?

I'm actually on vacation this week, but I couldn't resist sharing this small search challenge with you. 

A bunch of my dive buddies and I are in Bonaire, spending 3 to 4 hours a day diving in the 82F, ultra-clear, full-of-life seas around the island.  

When you dive, you're constantly seeing things that you don't know, and consequently, spending a fair bit of time searching for answers to "what kind of fish was that?" or "what IS that strange thing we found that looks like a snake, but has gills?"  

Here's a fairly easy question for you that should build your repertory of search skills a bit.  We've had challenges in this style before, but never quite so tropical! 

This is a fish you see everywhere around Bonaire (and most of the Caribbean as well).   I shot this picture yesterday afternoon at a depth of 30 feet (10 m).  This fish is about 2 feet long (0.6 m) from tail-tip to nose.  This is a very typical pose.  

Our challenges for today are: 

1.  What kind of fish is this?  (Looking for both the common name and the Latin scientific name.)  

2.  What contribution does this fish make to the geology of the island?  (That's not a typo:  this fish is important in making the island what it is.  Can you find out what/why/how?)  


As usual, please let us know the answer, HOW you found the answer, and how long it took you to search it out.  

I'm heading to go diving now.  Answers tomorrow! 

Search on! 

Followup: What made that mark on the land?

I wanted to follow up yesterday’s discussion of the mysterious “mark on the land” (which we now know was the short lifetime of the Penninsula Channel Commander’s RC model-plane airport). 

One of the most poignant memories of the old field is this video taken from a model plane of the “Old  Half Moon Bay Field” http://petej.com/blog/movies/#hmb  (Taken from Pete Johnson’s remembrance of the field which was closed and torn up on September 30, 2008.)   Here are a few frames from Pete's video, showing the field in close up, and with views up the coast.)  

Note the man walking across the strip.  It really is 40' wide.

As you probably saw from all of the comments, there are multiple paths to figuring this one out. 

I especially liked Rosemary’s use of Google Earth’s layers tool.  As she pointed out in the comments yesterday, the “Google Earth Community” layer can be a great source of insight. 

To get to that layer, search in the Layers menu:

Selecting the "Google Earth Community" layer.  Notice the "i" that appeared on the image.

And sometimes you’ll find useful information there.  (Rosemary did.)

With this one hint (the name of the club), everything else becomes simple. 

One trick I sometimes use in Google Earth is to turn on ALL of the layers at once (click the "Gallery" check-box) to see if I get any hits.  Note that you have to be fairly zoomed in, or you’ll get a million points appearing (which could take a while). 

But wait... there's more! 

As you noticed, several people found “Gordon’s Chute”  in the vicinity of the landing strip, thinking it was what I was after.  (I was a large pier that had a chute running from the top of the cliff to a mooring point just offshore—the idea was to simplify the loading of ships with deep drafts).

Now, in truth, I hadn’t heard of Gordon’s Chute before readers discovered it.   What a remarkable thing!  Built was built in 1872 and lasted until 1885, when it was destroyed by a storm.

Be sure to see John Vonderlin (aka BenLoudman) amazing “Gordon’sChute” Flickr pages.  (Thanks for pointing this out Remiij!)  This collection of images is a superb collection of what is there now, and what once was there (with a hypothetical diagram showing where it seems to have been, overlaid on current reality).  

Here's a sample: 

From John Vonderlin's Flickr page on Gordon's Chute

In Vonderlin’s collection, he has several excerpts from the “San Francisco Call” newspaper, with articles dated May 31, 1896. (San Francisco Call, Volume 79, Number 183, 31 May 1896 – easily accessibly at the CaliforniaDigital Newspaper Collection. )

As you can see from their illustration (done “From life by a Call illustrator”), the chute is located on a bluff near two rocks (where the remaining trestlework stands) and near a valley (which you can see on the right side of the illustration).

May 31, 1896.  San Francisco Call, v 79, n 183.

The reason I bring this up… is that the site of the model airplane field isn’t quite that location.  But it’s nearby. 

If you look at this picture (which I made from Google Maps), there are at least 4 locations where the Chute could have been.  The rocks near the airport are pretty sheer, and unlikely to serve as a base of the trestle.  But the rocks at positions #2 and #4 are fairly large and flat. 

Since John Vonderlin had such an interest in Gordon’s Chute, I did a quick search for

    [ Vonderlin Gordon’s Chute ]

and found that he’d written a letter to a blogger who specialized in the history of the coastline there.  In that post on the blog PescaderoMemories, he writes about walking up the beach to find the original site of the structure. 

“Continuing to hike through the riparian corridor as it emerges into the ever-widening canyon mouth, finally see the goal ahead, Gordon’s Chute, and the wave-washed end of the looming, sheer Tunitas cliffs.”

The description makes it pretty clear that the chute rocks are near the mouth of Tunitas Creek.  We know (from the Call newspaper) that the chute was built on rocks near a bluff, near the creek.  And when we look at the map, it’s probably the  #3 or #4 rocks.  Both of which are about 1 mile south of the RC airport. 

Interestingly enough, Wikimapia puts the site of Gordon’s Chute at 37°21'46"N 122°24'26"W which is the site numbered at #3 in the map above.  That makes sense.  It lines up with the illustration, and it’s a large flat rock… probably blasted into a convenient shape. 

Remarkably enough, as Ramón discovered by doing a street address search, the property is for sale for $2M.  (That's actually a great price, in local real estate terms.)  The real estate listing ALSO mentions that this was the site of Gordon's Chute.  

Yet another solution path was taken by my brother, Jeff, who’s a professional pilot.  As we’ve discussed before, using your social network (especially when they’re a network of people know are experts in the field) makes a good deal of sense. 

He posted my question to the ProPilots (a members only) site and generated a great discussion.  The pilots were initially confused and surprised.  Many of the pilots had flown in the area, and they would have known about a runway there, even abandoned ones are marked.  Then one pilot had an insight:  “I have a few thousand hours of instruction time around that area and I don't know what it is. The runway looks pretty small though. I know there's a spot in the area where people fly RC aircraft...” 

One pilot had a novel idea:  “If there are any RC pilots here, fire up RealFlight [an RC flight simulator, with many RC fields in the model] and check, I think there's a RC field in the sim that looks like that. (I'm on the road and don't have it with me).” 

I have to admit that I’d never thought about using a game as an information resource! 

Then, one pilot did the same thing I did and measured it on Google Earth.  “It’s only 400’ long.  Abandoned RC airfield?” 

It was a quick solution after that.  They didn't take long to discuss it and figure out what the right answer was.  

Search lessons:  There are many here. 

First, the journey sometimes really IS the reward.  Thanks for all the ideas about Gordon’s Chute.  I wouldn’t have known about this.

Second, triangulating information (that is, getting multiple, corroborating pieces of information from different sources) is necessary when the history is old and confused.  This is what we did above by looking at maps, old photos and old newspapers. 

Third, information can come from surprising places.  Social networks are one great source, but also real estate sites and even simulator games can be potentially useful sources! 

Fourth, sometimes using the tools you have in new ways can be useful.  Google Earth has a number of useful, often historical, annotation layers.  Oddly, those layers are not searchable, but you can investigate them easily enough with a click.  Remember the "Show all" trick as a way to quickly browse through the options.  

Excellent work by all.  

________________________________

Footnote:  BTW, I'll be on vacation next week, a trip that might well lead to an entirely new challenge.  Stay tuned.  If I can get to Wifi, I'll write up a new search challenge next week.  (But don't be surprised if there's just radio silence.  I might be off the grid!) 

Answer: What made that mark on the land?

First off, let me say Bravo!  The SearchResearch squad did a remarkable job on this challenge!  This wasn't an easy problem by any means, and yet the answer was found quickly and accurately.  Bravo, I say!  Bravo!  

Let me tell you what I did, and then reflect for a second on other approaches that people took, for they were really interesting.  

Remember, the challenge was: 

1.  What is (was) the reason for the long rectangle on the left near the cliff?  When was it built?  When was it destroyed?    

 Short answer:  It's a model airplane flying field.  Built in 200

2.  (Extra credit)  If you can figure out the first one, then the second one should be easy too:  Same question--what's the long linear feature between Highway 1 and the rectangle?  When was IT made?  And when was IT destroyed?  

When I first looked at the long, tilted rectangle, I immediately thought it looked like an abandoned runway.   The prevailing wind at this location would be a headwind for this angle, so it made a certain amount of sense. 

Since I know that archival aerial imagery is easy to get in Google Earth, I just launched Earth and started exploring with the Time slider.  (Remember that we used this method before to search for other archival land images.  Just click on the tool that looks like a clock in the Google Earth toolbar.) 

With the Time Slider, I was able to quickly zoom back in time to 2003 and see that there really WAS something there. 

Google Earth image from 2003

Google Earth image from 2008

Google Earth image from 2009

As you can see, this pretty clearly IS some kind of airport / landing field.  But whatever kind of airport it was, it didn't last long. This same site in 1993 is a complete blank. 

Google Earth image from 1993

But the "X"s on the runway images from 2003 and 2008 bothered me.  So I looked up what an "X" mark would mean on a runway.  My search for: 

     [ X mark on runway ] 

led me to the FAA runway marking guideline which says that an "X" on the runway means it's closed.  

But that's odd too.  Why would someone build a runway, then immediately close it?  Or maybe never open it?  

I then spent a fair bit of time (probably 30 minutes or so) searching for closed or abandoned runways, air strips, landing strips, air fields...  etc etc.  I found a lot of interesting content about closed airports in the greater San Francisco Bay area, but nothing down south of Half Moon Bay, near the small town of San Gregorio (the next town south of this location). 

One other thing bothered me about the photo from 2003.  If those white things on the right side of the image are cars, then that would mean the runway is about 2 or 3 car lengths wide.  That seems narrow for an runway.  So I went back to Google Earth and used the Ruler tool to measure the length of the runway. 

The runway (in yellow) is only 383 feet (~100 m) long???

What's going on?  It's 41 feet wide and 383 feet long.  That's way too small for a real runway unless it's some strange kind of VTOL or STOL aircraft.  Even so, the staging area and ramps are too small for that purpose.  

Now what?  

Like a few other SearchResearchers, I remembered that there was a project to fly up and down the entire coastline of California.  I couldn't remember the name of the project (or website), so I did the search for it: 

     [ photographs California coast ] 

And found the California Coastline Project (http://www.californiacoastline.org/)  

Once there, I searched for "San Gregorio"  and then went a couple of clicks northward up the coast to that point where the bluffs are high and the land is flat.  And found that the image of that location has a very visible green runway on it.  (Wait a second.  GREEN?)  And the label "San Mateo RC Airport." A quick search for the term "RC airport" revealed that this is a remote control airplane airport!  (See the image from the California Coastline project below.)  

Ah.  So that's why I wasn't finding anything when looking for "abandoned airstrip" or "runways."  It's not a regular airport.  And that's why it's too small.  A ha!  

I figured that anyone who would put this much trouble into making an entire tiny airport for remote control airplanes was probably part of a club, and that I could find their website (or at least a mention of them in a club newsletter or something).  

My next query was: 

     [ rc airport san mateo coast california ] 

After clicking into the link labeled "R/C flying fields California," I found that there's club operating out of Half Moon Bay (the next largish city to the north), the "Peninsula Channel Commanders" club.  

There's even a photo of their airstrip on their website.  It looks very similar... but not quite the same as the air strips shown above.  Huh.  So clicking on the link to the field directions, I found that their current field is way north of where we've been looking.  Sigh.  Not quite right. 

But the similarity between their current field and the one in the images above struck me.  So I clicked on the link to their History page and found this. 

In 1999, the group moved to a field on the west side of Highway 1 owned by the Deany family. This beautiful location was a bit close to the ocean: many a plane splashed into the Pacific. 

A change in land ownership in fall 2008 left the group without a field for a few months, then we found a field a bit closer to Half Moon Bay, owned by John Giusti. We began flying there Feb. 1, 2009, after Eddie Andreini graded the area and volunteers set up the necessary gear.

  This history lines up with the images we found on Google Earth ("west of Highway 1" and "a bit close to the ocean") and explains why the airstrip only lasted a few years.  

I then remembered another great geo-resource, the GeoHack site (http://tools.wmflabs.org/geohack/) which pulls together all kinds of geo-located information.  By zooming in on our lat/long from above, I found this map: 

The green rectangle suggests there's a known feature here.  By clicking on the Wikimapia "+Old places" link, I end up on the Wikimapia site: 

When you roll over the polygon overlaying our target, it shows up as "Model Airplane Field."  

So we've figured this one out.  It was the R/C model airplane flying field for the Peninsula Channel Commanders. Here it is in its heyday (2002).  

Copyright © 2002 Kenneth & Gabrielle Adelman. All rights reserved.

And now, onto the extra credit part.  

If you look at the Wikimapia map, you'll see the long, slender rectangle labeled as the "Ocean Shore Railway."  To confirm that it's a railroad, just zoom out a bit.  With a little dragging and panning of the map, you'll see there's a long line visible on the ground that stretches all the way up to Daly City (although you have to jump to the other side of Half Moon Bay when you get there).  

You can read a brief summary of the railroad at the Wikipedia article about it.  But for a wonderful read, check out "The Ocean Shore Railroad" by Chris Hunter (2004).  

Here's a map I found (Image search).  Grand dreams, never quite realized. As you can see, it went down the coast from San Francisco, through "Spanish Town" (now, Half Moon Bay) and through San Gregorio.  

So this is a remarkable bit of history.  Some of it is ephemeral--the RC airfield lasting only a few years--and the railroad, lasting only a few years, but whose mark on the land has lasted for over a century.  

I have much more to say--especially about how SearchResearchers found their solutions.  (AND about the discovery of Gordon's Chute, which I totally did NOT expect.) 

But this post is getting to be too long as is.  I'll write an addendum later today / early tomorrow with those comments.  

FWIW, I spend about 45 minutes running through all of these steps.  And I didn't get sidetracked by other things.  This was a hard problem!  

Excellent find, everyone.  

Search lessons: Google Earth is great for archival imagery of an area, but as you go farther back in time, the snapshots get too far apart to be definitive.  Useful starting point, though.  

Using other earth imagery resources is often helpful.  Some places (e.g., California Coastline Project and GeoHack) can provide you with very different perspectives on the same location.  It's useful to check them out as well. 

Also, I was initially fooled by the appearance of the landing strip.  It wasn't until I measured the size of the strip (using Google Earth's ruler tool) that I realized something was fishy.  Lesson: Check even the obvious for oddities.  

More on this topic later...  But for now, nice job.  

Search on!