SearchResearch Challenge (11/29/17): What kind of horn is that thing? Is it for real?

I went to a concert the other evening... 

... full of Baroque and Renaissance music, held in a lovely chapel late in the evening--the performers played shawms, traditional bagpipes, recorders, sackbutts, and a stray hurdy-gurdy.    

As we walked in, the usher handed us a program that was illustrated with this strange and wonderful illustration (this is a scan from the program cover illustration).  

It's clearly snipped from a larger illustration.  But it intrigues me.  Is this a real thing?  Or just some illustrator's imagination run wild?  

Here's today's Challenge: 

1.  Is this a real instrument?  Or is it just a made-up thing?  If it's real, what would you call it? 

2.  Can you find the original source of this illustration?  When and where was it first published?  

This isn't all that hard to do, but I had to poke around a bit to find the original.  Let us know how you found the source of this somewhat fanciful illustration!  

Search on! 

Answer: What causes such crazy cone and flower production?

This past week we had a harvest-time Challenge.  


It's Thanksgiving in the US, so our questions about sudden increases in pine cone production (and therefore, the production of pine nuts, which are just about my favorite tree product ever)  seems relevant. 

Remember that our Challenges were driven by seeing pine trees like this: 

1.  Does dying (or nearly dying) lead to a sudden efflorescence in plants?   

2.  If so, what causes this effect?  How does the plant "know" this, and respond? 

3.  Is this "sudden efflorescence" from a near-death experience true for any other plants?  

This was a tough set of Challenges, but we figured it out!   Here's what I did... 

Like many of you, I started by searching for: 

     [ dying pine cone production ] 

and variations on that query.  

     [ dying pine cone bumper crop ] 
     [ dying pine cone mast crop ] 

Mostly, these searches seemed to go nowhere. Sigh. I read a lot about pine trees dying from beetles and drought, but little about the connection with a sudden flowering (that is, an efflorescence) of cones.  I learned that pine trees produce varying numbers of cones each year, so there's year-to-year variation.  I was beginning to think the idea of "dying pine trees producing large numbers of cones" was a complete myth.  

But... as I was quickly scanning a fairly low-quality site, I noticed the term "stress crop" used to describe a sudden outburst of pine cones on trees that weren't exactly dying, but were not in good shape.   

Frankly, I didn't hold out much hope for this term (it was a really crummy site), but it gave me a new way to think about the language of pine trees and sudden large crops of cones.  So  did a search for: 

     [ "stress crop" pine cones ] 

and found a number of higher quality sites that told me a bit about how stress sometimes causes plants (in general!) to flower in large quantities.  From the first few results I learned: 

1. Stressed trees produce more seeds, and pine trees in particular produce more cones when stressed by drought or insect defoliation.  (From NorthernWoodlands.org - the author is a forester and commissioner of the Vermont Dept. of Forests, Parks and Recreation) 

2. Pine trees stressed by drought will produce a "stress crop," that is, an abnormally high number of cones.  (From the Oregon state Dept. of Forestry)  

3.  When Shortleaf pine (Pinus echinata) is stressed by Littleleaf disease, about 3 years before they die from the disease, Shortleaf pine trees commonly bear an unusually large crop of  small cones known as a "stress crop."  (From the USDA National Agricultural Library, an article by the US Forest Service on reducing losses of forest trees by a number of different stressors.)  

4. Pines that are suffering from Armillaria root disease often leads to chlorosis (yellowing) and heavier-than-normal productions of cones (a stress crop of cones).  (From The American Phytopathological Society article about Armillaria root disease, aka "shoestring root rot.")   

So, I learned a new and productive phrase to describe the sudden burst of pine cones from a pine tree that's stressed by disease or drought.  


Our second question was "how does the plant know this?"  This sounds a bit odd (how does a plant "know" anything?), but let's try to unpack this idea a bit.  

Large Lodgepole pine cone crop caused by stress

What I meant was "how does the plant figure out that it's time to produce a massive crop of cones?"  In order to suddenly go from few cones to a "stress crop," something has to happen in the tree to make all of the branches suddenly start producing cones all at the same time.  

The only way I know of for a tree to do that is to produce some kind of hormone that gets shared between all of the branches, causing a sudden efflorescence of cone production.  


The obvious query at this point would be: 

     [ "stress crop" hormone ] 

From one book (Mechanism of Plant Hormone Signalling Under Stress) I learned that "...plants have developed an intricate web of complex machineries to translate perceived stress signal into effective response by modulating the gene expression or directly affecting the physiology of the cell..."  

Okay--so plants DO respond to stress by using signaling hormones to make things happen.  But what is that hormone for pine trees? 

While the results from this query told me a great deal about hormone signalling (and confirmed that stress can cause various hormones to signal plant changes), I really want to find out about pine trees and cones.  I modified the query to be:

     [ "stress crop" hormone pine cones ] 

This gave me much more focused results, including an article from Montana State University Extension (Pruning Trees for Health, Shape and After Storm Damage) with the useful paragraph in a section about the effect of hormones on tree growth: 

As summer progresses, tree energy priorities may also be redirected towards seed/fruit production. An interesting phenomenon for many trees is the “stress crop” effect. Trees that are stressed may divert energy towards a plentiful seed/fruit crop as a “last gasp” before they die as a mechanism to ensure species survival. A heavy seed crop on a scrawny tree may indicate imminent death rather than health and abundant energy. Fruit growers use this effect by pruning trees every late winter in manner that does not weaken overall tree health but that stimulates a “stress” seed (fruit) crop. 

That's fascinating (and goes partway towards answering our third question).  

In another fairly technical article Cone Production in Conifers (published by the Pacific Forest Research Centre, part of the Canadian government), we read that there are many factors that determine overall cone production rates.  There's the cyclical nature of some species (abundant in some years, and then again some number of years later), but also average annual temperature, moisture, fertilizer, and... stress.  In particular, stresses of dehydration, wounds to the outer layers of bark, insect attacks all lead to stress crops.  Stress causes a rise in the level of gibberellin, which is associated with intense cone production.  

Aha!  I just learned a new search term that's associated with pine cone production.  If I do a new search for: 

     [ gibberellin hormone pine cones ] 


This leads me to many more (and increasingly technical) articles on how gibberellin hormone response causes a stress crop response.  

In particular, the paper Plant growth regulators and cone induction in Pinaceae (from the Centre for Forest Biology, University of Victoria, BC, Canada) is a wonderful primer on what causes pine cones to form on pine trees.  They have an extensive discussion about what hormones cause pine tree flowers (and therefore cones) to form:  

The traditional methods for improving seed yield involve treatments to manipulate physiological conditions of the parent trees, which in turn enhances flowering. Flower enhancement is achieved by either physically stressing the trees, altering the tree’s nutritional status by applying various inorganic fertilizers, or applying growth regulating substances such as gibberellins (GAs)... 

This was also a fascinating paper, not least of which was for it's plaintive comment about how hard it is to do this kind of research, talking about a fruitless search for a hypothetical universal flowering hormone:   

 There is a long history of studies whose goal was to enhance flowering [and cone production]. For decades, the search for a universal floral induction mechanism and its universal compound – florigen - consumed many careers...

But this paper also gives us the answer to the "how the tree knows" Challenge.  

Summarizing here:  When a tree is stressed, either by physical damage or by the roots receiving less water than they prefer, the needles, or bark, or roots release one of several hormones (e.g., ethylene or abscisic acid) which then causes the tree to start producing one or more different types of gibberellins, which in turn cause cones to form.  

If the stress is large enough, a massive crop of cones form. 

Obviously, if the stress is long and large enough, the tree dies--covered in cones.  But if the stress is removed, the tree might well recover and live another year.  


The third Challenge asks if this same concept applied to other plants as well.  I gave the example of my poor, under-leafed but over-flowered bougainvillea: 



I began this search with: 

     [ stress-induced flowering bougainvillea ] 

and discovered that not only is this a thing, but it's quite common to withhold moisture from a bougainvillea to get it to produce lots of flowers!  Here's a quick guideline from a newspaper gardening section:  

Bougainvillea flowers heaviest when the plant is water-stressed. Bougainvillea growers often withhold water for extended periods to force the plant into bloom. To stimulate blooming this way, withhold all water until the leaves begin to wilt. Then water thoroughly. For regular maintenance, water only when the soil is dry but before leaves show signs of stress. Mature, established vines rarely require watering. They flourish with calculated neglect.

I believe it, but I thought I'd do the same query in Google Scholar and see what would show up there (looking for a somewhat more authoritative answer).  I found pretty much the same thing in a journal article titled  "Stress-induced flowering" from Plant Signalling & Behavior.  In the article they point out that not all plants respond to stress in the same way, but that stressors such as  low nutrition, drought, poor nitrogen, poor oxygen, and girdling cause many plants to flower.  (Especially, they point out, any and all stressors cause Douglas fir to flower.)  

Another article ("Effects of shoot bending on ACC content, ethylene production, growth and flowering of bougainvillea" from the journal Plant Growth Regulation) tells us that stress on a bougainvillea (such as shoot bending, which stress the branch) cause an increase in ethylene production (which we learned above), causing it to flower earlier and productively.  

What about other plants?  I repeated the query without the bougainvillea: 

     [ stress-induced flowering ] 

and found that stress causes not just pines and bougainvilleas to flower, but also citrus of many kinds, Cyclamen, mangos, and pineapples.  

Pineapples?  

Yes!  In their paper "Forced flower of pineapple (Ananas comosus cv. Tainon 17) in response to cold stress, ethephon and calcium carbide with or without activated charcoal" (published in Plant Growth Regulation journal), the authors show how spraying field pineapples with either (1) an ice-slush, or (2) calcium carbide (which generates ethylene when mixed with water!) will cause flowering to take place.

Bottom line:  Many kinds of stress can cause plants to flower--including pine trees, mangos, pineapples, and bougainvillea.  When stressed by drought (which is very common in California over the past few years), pine trees will create a "stress-crop" of cones, easily seen on the branches.  


Search Lessons 

There are many lessons here.  Here are three to get you going: 

1.  You often find answers to other questions while looking around.  That's why it's useful to jot down your research questions before you start.  That gives you a way to structure your note-taking, and you know what the pay attention to as you research. 

2.  Pay particular attention to unusual terms or phrases you run across.  These are often the key to making exactly the right query.  In this example, "stress-crop" lead to all kinds of discoveries, as did finding the term gibberellin, which led us to finding all kinds of articles about plant hormones that drive the flowering (and pine cone) process.  

3.  Scholar is really useful for technical questions.  In this case, we used Google Scholar to find very authoritative references in the botanical literature.  These were often fairly detailed (and took a lot of looking up of specialty terms), but valuable in the end. 



Search on! 

(And Happy Thanksgiving to everyone!)  

SearchResearch Challenge (11/15/17): What causes such crazy cone and flower production?

There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune;
Omitted, all the voyage of their life
Is bound in shallows and in miseries.
On such a full sea are we now afloat…


This is from Shakespeare's Julius Caesar, at the moment when Brutus is encouraging Caesar to act because the time is right, and there's no better time likely to come soon.  

There's an equivalent moment in the life of plants that's equally propitious... Or is it?  

I've noticed something as I wander around, looking at plants and trees:  Sometimes the pine trees that look to be in terrible shape often have the most pine cones.  

Is there a connection here?  Do dying pine trees actually produce a last gasp of cone production?  And if that's true, should I worry about those pine trees that suddenly produce a bunch of pine cones? 

I was also noticing this about the bougainvillea in my front yard.  As you can see, there are lots of flowers on it, but very few leaves.  

This is a beautiful plant, but it's not really very robust.  It SHOULD look like this (from the Carmel Mission, near Monterey, CA):  

This observation about the "tide in the affairs.." of plants leads to this week's SRS Challenge: 

1.  Does dying (or nearly dying) lead to a sudden efflorescence in plants?   

2.  If so, what causes this effect?  How does the plant "know" this, and respond? 

3.  Is this "sudden efflorescence" from a near-death experience true for any other plants?  

When I searched for this, I found that I had to learn a bit of language in order to make good queries.  

Let us know how you found the answers!  

I'll be back in a week (Wednesday, Nov 22) with my answer.  In the meantime, may you and all of your plants and trees be in good health.  


Search on! 

An itinerant scholar in the Age of the Internet

As you probably noticed... 

... I've been traveling a bit--hence the slightly erratic SRS posts over the past month. This will probably continue for a bit more time as I keep moving around the planet.  

  

Taveuni, Fiji

Both the springtime and the end of the year tend to be a busy time for me.  In the last 3 months of 2017, I will have visited Taveuni, Fiji; San Diego, CA; Washington DC; Pensacola, FL; Chapel Hill, NC; Knoxville, TN; College Park, MD; Cairns, QLD; Brisbane, QLD; Poughkeepsie, NY; and New York City, NY.

Pensacola, FL

This is what comes from being an itinerant scholar.  Even now, in the Age of the Internet and high bandwidth connections with live streaming 360-degree video, there's still an ineluctable value in actually being present.  



Why is that?  Couldn't I just phone (or video) it in?  

Knoxville, TN

As my friends Judy and Gary Olson wrote in 2000 paper, Distance Matters.  One of the more surprising findings from their studies is that people behave differently when they THINK you're far away.  It's a kind of unconscious bias: if I believe you're far away, then I tend to trust what you say less.  This is makes no rational sense, but it's been studied many times.  

What's more, when I visit you in your workplace (or university), we have the chance to have lots of informal, high-touch (notice I didn't say "high-bandwidth") interactions.  I've been in a lot of high quality videoconferences, but the quality of physical presence (with all of the nuances that seem to get lost over video) is powerful.  

UCSD, La Jolla, CA

What's more, when I visit you, we can have informal side discussions that are incredibly valuable.  When you're on a video call, the conversation is framed within the time of discussion--everything before and after (which turns out to be incredibly valuable) doesn't happen.  

Even though physically traveling to another venue is kind of a hassle--it's almost always worth it.  (Especially when that venue includes scuba diving, which doesn't work well over video...)  

Besides, when I travel, I pick up all kinds of ideas for SRS Challenges.  You'll be seeing a few during the next year!  

Me playing chess with statue. Georgetown, DC.
I think I'm winning.

In other news, I'm also trying to finish up my book.  I'm realizing just how much time writing a book takes.  Even if you've got over one thousand blog posts to draw from, editing some of them into a reasonable book takes a huge amount of sitting-and-typing.  

Thanks for hanging in there with me as I travel hither and yon.   It'll all be worth it! 




Still searching!  

















Reference:  Olson, Gary M., and Judith S. Olson. "Distance matters." Human-computer interaction 15.2 (2000): 139-178.

Answer: How many people die each year in the US?

How many and how people die,

.. it's complicated.  

More to the point, just figuring out which data sources you can trust for this kind of information is trickier than I would have thought.  

I asked you about your intuitions, and before I did any research on this, I wrote down a few of mine: 

     A. What fraction of people die from car accidents?  

     B. How many people die from other kinds of accidents?  

     C. How many people die of different medical conditions?  

     D. What are the leading causes of death?    

My guesses, before having done any research: 

A.  Car accidents:  15% of total deaths / year 
B.  Other (non-car) accidents:  5% / year 
C.  Medical conditions (not including old-age):  50%  
D.  Leading causes of death (of any or all causes), in order:              Accidents; Heart problems; Cancer

Let's see if we can answer these questions:  

1. How many people die (from all causes) each year in the United States?  

2. What are the top 5 causes of death in the United States?  (As a fraction of the whole.)  

As I mentioned, the interesting question is going to be:  Where do you get your data from, and why do you believe it's accurate?  

The obvious queries on different search platforms gives different numbers.  There's variation in the answers even within a single search platform.  Compare these results with slightly different queries on Google:   

Notice that there's a 250,000 person difference between these two numbers.  Why?  Because they come from different sources.  The first query gives a webanswer from a webpage at www.medicalnewstoday.com (which in turn gets its data from the 2014 CDC numbers), while the second query shows an answer that's from Quora.com with data from the UN data source, UNstats.un.org, and these numbers are from 2008.  

Oddly, the first article tells us that the CDC data is no longer available.  The link Medical News Today cites IS broken, but the obvious query: 

     [ CDC 2014 data deaths ] 

takes you to their "National Vital Statistics Report" which has exactly the same number: 2,626,418 in 2014. 

If you click on the Quora link in the second query [how many people die each year in the us], the writeup there takes you to the UN demographics report from October 2017, which tells us the total number of deaths for 2015. 

Looking at that page you see the entry for the US: 

From UN demographics report

READ CAREFULLY:  The Quora article says that "the most recent data available is from 2008."  But this data is from 2015 (the date is in the gray column), and the report was updated on 16 October, 2017... but notice that the number shown here is different from what's in the summary!  Here, the UN says it's 2,712,630 deaths in 2015. As opposed to the 2,473,018 deaths reported in the 2008 UN summary seen in the webanswer. Notice that we're comparing deaths in 2008 vs. deaths in 2015--of course there's a big difference.    

Think about what this means:  Of course, you'd expect the total number of deaths to change year-by-year: the overall population increases year-by-year, and the death rate changes as well... just much less than the overall growth in population.

Okay--so can we find the CDC data from 2015 to be comparable with the UN data?  

I noticed that in the CDC report we found above, the actual text in the paper was this: 

"In 2014, a total of 2,626,418 resident deaths were registered in the United States..." 

I know that these kinds of reports are often written from a template.  (That is, they probably just copied the report and plugged in the new numbers for 2015.)  So I did this query to find the report for 2015: 

     [ "In 2015, a total of * resident deaths" ] 

Notice that I changed the year to 2015 and used the * operator to match the new number for that year, and I double-quoted the whole thing to find a match for this exact phrase.  

Voila!  That takes me directly to the CDC report for 2015 where we find out that " A total of 2,712,630 resident deaths were registered in the United States in 2015."  

Let's compare these numbers from CDC and the UN: 

2014
UNC   2,626,418
CDC   2,626,418 

2015
UNC   2,712,630
CDC   2,712,630  

Notice anything odd about these numbers?  They're exactly the same!  If you go back a few years, you'll see more of this pattern. Which makes me wonder:  Where does the UN get their numbers?  From the CDC!  (After looking around, I found that nugget in a footnote, of course.)  

Which means that although we've "double sourced" this data, it's actually NOT double sourced--the UN is just taking whatever data the CDC hands them. 

You might be tempted to think that the UN is getting their data from a different US source; after all they give their data citation as coming from the "U.S. National Center for Health Statistics" in their "National Vital Statistics Report."  But when you look up the NCHS, you discover that they're a department of the CDC.  It turns out that they're the people who collect the data in the CDC!  

This is an interesting insight: the simple question How many people die each year in the United States? turn out to have a more complicated answer.  It varies by year, and as you might imagine, it varies depending on how you measure it.  

WHAT?  Isn't a death a death?  Can't you just count death certificates?  

Well, yes, but are you also counting people who disappear?  What about US citizens that die overseas?  Are they listed as a US death, or as a death in that country?  Are you counting from January to January, or just one month-long period and multiplying by 12?  Are abortions counted as deaths?  Stillbirths?  What about people in Puerto Rico, the US Virgin Islands and other territories?  (Why are the Virgin Islands broken out into a separate line item in the CDC report?)  What about military deaths in non-US locations?  

As often happens, once you start digging into a research question, you learn a lot about the area.  You learn the little details about your question that deepen your understanding of the question you're asking. This happens all the time when we do our SRS Challenges:  What starts out as a simple question turns into something larger and with more nuance than you thought at the start.  

In each of the questions I asked above, you can find the answers in the data commentary that's usually at the bottom of the data set.  (Sometimes it's scattered around in the text itself.)  But it looks like this, usually presented as footnotes: 

The notes describe the properties of the data: in this case, footnote #36 tells us that military and US civilians who die outside of the country are NOT included in the totals.  

In this case, we found out that which year you're asking about makes a big difference.  

What about that other question, causes of death in the US?  

Those same reports also break down the causes by percentages of all US deaths.  From the CDC report on health issued in 2017 (with data from 2015), we find that the top 5 causes of death in the US are: 

1. Heart disease (23.4%)

2. Cancer (22.0%)

3. Chronic Lower Respiratory Disease (CLRD) (5.7%)

4. Accidents (5.4%)

5. Strokes  (5.2%)

They illustrate this nicely with this chart (from the previous CDC reference):  

From CDC report, "Chartbook on Long-term Trends in Health"  pg. 18

As you can see, heart disease and cancer are the two largest causes of death, accounting for 45% of all deaths in 2015.  CLRD, the next most common cause, is only around one fourth as much.  

When I look back at my guesses (at the top of this post), I see my intuition was really wrong.  Accidents of all kinds are around 5.4% of the total (which means that car accidents are less than that).  

We may worry about mass murders or the latest version of flu, but the big killers each year are heart disease and cancer.  They are much more significant in terms of public health than anything else by far.  

When you look at the causes of death over time, it's a fascinating piece of data: 

Same source as above.  Notice that the Y-axis is a log scale, which means that a little big of change coming down (e.g., heart disease or stroke) is actually MUCH bigger than it might seem. That decline looks much less than it really is.  The improvement over 40 years is amazingly good.  Note also that CLRD is a new disease label that combines asthma, bronchitis, emphysema.  In 1999, the disease coding system changed to recognize those diseases as a cause of death, and separated out pneumonia and the flu into a separate category.

What is so striking is how constant many of these numbers of deaths are: Why do roughly the same number of people die each year in accidents? 

This chart also has good news / bad news: We're getting better at managing heart disease, but the overall cancer rate hasn't changed much in 40 years.  

And of course, another big factor in the causes of death is age at time of death.  People die of very different causes at different ages.  I saw a data table that suggested this, so I did the search to see if I could find a summary chart.  

     [ site:cdc.gov causes of death by age ] 

and found this chart in the CDC chart collection for causes of death, which shows how people die for very different reasons at different ages.  While cancer and heart disease are the largest causes of death, they come into play only after age 44.  Before 44, you're more likely to die of an accident.  

Search Lessons 

1. When looking at data, be SURE you understand WHEN it was collected and WHAT it's measuring.  As we saw, different sources (Alpha vs. Bing vs. Google) all draw on slightly different resources from different times.  This makes a big difference. 

2. Consider other factors that might influence your data.  In this case, death rates vary a LOT by age.  (They vary by other factors too, such as gender, race, and location--but I just focused on age in this post.)  Be sure you understand all of the aspects of the data that are important to you. 

3. When you need the "next document in the series," remember that those documents often use boilerplate language, which you can find with a fill-in-the-blank query, like  [ "In 2015, a total of * resident deaths" ].  This is an amazingly handy trick to remember.  

4.  Be sure you know where your data comes from!  I naively thought that the UN would have different data than the CDC--but noticing that their numbers are all the same drove me to check where the UN data came from... and it was... the CDC.  This data is NOT truly double-sourced!  




Search on!  

(I'll post a bit of background about why this one took so long to write up in my next post, later this week.  Let's just say travel go in the way.  And... I'll put out a new Challenge on Monday.  Stay tuned!)