Monday, January 23, 2017

SearchResearch Challenge (1/23/17): Searching by not overthinking it...

Simple really is best.  

This perhaps most true in your SearchResearches.  

And yet one of the most common search mistakes I see in my studies is people using WAAY too complicated terms to search for simple things. 

Here are a few quick Search Challenges to make the point. You should be able to figure out what these things are very quickly... and WITHOUT USING Search-By-Image.  (Yes, I know you can find these things with Search-By-Image--my point today is to help you learn to search by taking the simplest possible route.)  

What would be the simplest possible searches for these things? 

1.  What kind of beast is this?  (And what's the simplest search that will get you the answer?)  



2. When it snows gently at night (as it did many nights when I was a grad student in Rochester, NY), you can see the most beautiful display of lights around the parking lots.  What is this phenomenon called? 



3.  And lastly, many animals have this strange extra eyelid.  What's it called?  

P/C Wikipedia.  (But don't click on this link to find the answer!)  

These are hard, but completely fun... once you figure out that the answer is really straight-forward!  

Search on!  


Thursday, January 19, 2017

Finding immersive experiences (Part 2)

Every so often... 

... one gets reminded of what they don't remember.  In this week's case, Regular Reader Fred Delventhal left a really nice comment on yesterday's post.  He wrote (minor edits are mine): 

Youtube filtering allows you to limit your search to 360 degree videos.  If you search for: 


          [ how to find 360 videos] 

you'll find a GoogleSystem blog post about how to search for 360 videos.  
This post from 2015 shows that you can filter your YouTube results by applying the 360 filter.   
To do this, first do a quick search, then click on the "Filters" pull-down menu:   


 Then, filter appropriately:  


Then you'll see the video on that topic with the 360 tag.  (I had a good time with the search for [ dolphins ] and then filtering by 360...)  



Fred also notes that: 
The Street View app for iOS and Android is basically all photospheres. Pick a point on the map and zoom in to see professional and user created Photospheres. The apps allow you to create your own immersive experiences of where you are.  You can use either Cardboard view or Magic Window.  
Note that Google Expeditions doesn't incorporate video yet (only Photospheres). They are working on it though... 
 
Check out StorySpheres as another place for 360 Photospheres with audio.   
Finally, a must try is Google's Spotlight Stories. The app is available for Android and IOS plus the videos are available on Youtube. (To find them, search for "Spotlight Stories" in YouTube.)  
 
P.S. Thinking outside of the box - Check out the "Where's Waldo 360" video. It's wonderful!
Note that these are all APPS, and not always available on the web.  Still, I should have included these in my discussion.  

Thanks, Fred.  I knew this once upon a time and I had forgotten.  More importantly, I ALSO forgot to do the search you did, the [ how to find ... ].  

And that's our Search Lesson for today.  Always check the basics before you write up the answer!  

Search on.... 

Wednesday, January 18, 2017

Answer: Finding immersive experiences

How do you get immersed,
 if you can't find what you
want to be immersed in?

There are lots of "immersive" videos out there.  Here's a nice example from David Hsieh: 


And we know about the NYTimes VR stories.  
But how do you search for these things?  

The SearchResearch Challenges: 
1.  How DO you find immersive online experiences?  (I've mentioned videos as one way to be immersed.  Are there other ways to get that experience?)  

Let's start by figuring out what an "immersive online experience" could be.  If you start with the query: 

     [ immersive online experience ] 

  you'll quickly learn that this can refer to: 

a. 360 still images--pictures that let you move your viewpoint anywhere (up, down, left, right, zoom in-and-out).  These often have extra buttons you can click to see inserted annotations, pieces of text, or videos.  Examples:  Discovery Channel's Deadliest Catch that lets you look around the wheelhouse of one of the boats in the series.  Tatlarin Church Cave in Cappadocia, Turkey from the International VR Panorama collection.  Of course, Google Photospheres are another kind of 360-still-image as well.  A nice example that's embedded in a Map is this one from the high mountains in Nepal.  (See below for more info about finding Photospheres.)  

(Unfortunately, we also learn that these kinds of images are sometimes also called panoramas, or VR images.  The terminology is a bit ambiguous.)  


b. 360 videos--these are videos that let you move your viewpoint anywhere as the video plays. In essence, it's a stream of 360 still images that create the video.  Examples: the diving example from Green Island (above), or this one from MythBusters (Discovery channel again): Sharks

c.  VR application--this is the full-on Virtual Reality experience, with 360-steerable video, usually of synthesized video scenes, with a way for you to direct your movement and/or interact with the objects  or other people in the scene, as in Second Life (the VR world). You can play/live in Second Life now, or watch someone playing in a VR environment, but at the moment, these are all fairly specialized apps, so for the time being, they're not part of what we're going to look for.  (Maybe we'll cover this topic in a year or so...)   

But here's the thing:  How do you find these 360-images or 360-videos?  They seem to have a variety of names (panorama, 360-video, immersive video, VR video, etc).  Some even require specialized applications to run on mobile devices (e.g., Google Expeditions, which are 360-videos that can be used in the classroom, and work for multiple people in the environment at the same time).  To see where all this is going, here's interesting new immersive house tour app.  (It's quite nice...)    

And worse (from our perspective), there's no consistent filetype, URL, or pattern we can search for!  (By contrast, if you wanted to find videos, you could search for filetype:MP4 or you can search on YouTube, Hulu, or similar.  But what's the equivalent for 360-immersive videos?) 

Sorry, but there doesn't seem to be any really great way to do this.  

The best advice I can give you is to look at well-known collections of 360-videos.  

Start with YouTube.  If you search for: 

     [ virtual reality channel ] 

you'll find a number of collections, including channels that are dedicated to just VR videos.  (Of course you should do the same with the query [ 360 videos ] as well, just to get a more complete set of channels.)  



On the other hand, many news services now have their own YouTube channels that you can search.  For instance, the BBC has their BBC YT News Channel (and in there you can search for [ 360 videos ] and find a long list of immersive videos).  

To do this, click on the magnifying glass icon in the YouTube channel page, then you can do a search for something like [ 360 video Hadron collider ] to get the 360 immersive video tour of the Large Hadron Collider.  


Likewise, the New York Times has its own immersive video channel, but in their channel you have to search for [ 360 VR ] to get the complete list of their videos.  And, unfortunately, not all of the NYTimes VR experiences are on their YouTube channel.  To find others, you have to visit their video site:  https://www.nytimes.com/video  At the moment, their search function seems broken, so you can't even use their search tool to find things.  Since they don't always tag their 360 videos in a consistent way, I don't know how to find all of their 360 / VR / immersive videos!

The Discovery Channel has 360 videos, but in each case you have to add "360 video" to your queries.  
So.. the state of the art at the moment seems to be this:  
You have to know where to look, and then search within each of those sites.  Sorry.  (If something gets better in the future, I'll post an update.  But at the moment, 360 / VR / immersive videos are inconsistently labeled and don't share a file format, so... Good luck.)  


2.  How can you find immersive experiences by location?  For instance, can you find all of the immersives that are near the Wat Chedi Luang temple in Thailand, especially ones that show the famous reclining Buddha?  For instance, can you also find an immersive that shows you the view from the mountain peak that's about 5 miles (8 km) to the west of the temple?   
Reclining Buddha at Wat Chedi Luang temple, Thailand.

Remember that Photospheres are a kind of immersive image (or panorama)!  And how do you find Photospheres?  (We covered this a while back, June 26, 2015 SearchResearch--New Streetview of El Capitan and how to find Photospheres.) 
Knowing that Photospheres are located on Maps, I just did a query on Google Maps for: 
     [ Reclining Buddha at Wat Chedi Luang temple, Thailand ] 
and found this map... 

Click to see the expanded version. 

And it just so happens that the first photo (in the lower left corner) is of the Reclining Buddha!  


Remember that clicking on the yellow pegman in the lower right of the map will show you all of the StreetView locations (the blue lines) AND the Photosphere (the blue circles).  


Now, if you just zoom out, turn on the Terrain view and look to the west, you'll find the closest peak just 5 miles away (Wat Phra That Doi).  

And once you click on the Pegman, you'll see the available Photospheres at the peak. 


And if you click on the easternmost Photosphere, you can get a nice view to the east. 

Yes, there's a balcony artifact, but so it goes...
If you look carefully at this image, you can see the airport in the middle right. That's the same airport you can spot two images up in the map of the region with Terrain view turned on.  


Search Lessons 


First off, I was late posting this Answer to the SearchResearch Challenge because I spent a LONG time trying to find a good way to search just for 360 videos.  I thought there HAD to be a way to do it (other than the method I wrote about above), but no... there just doesn't seem to be any way to do it!  As I said, there's no common file format (so we can't use filetype:), and there's no consistent naming, hashtags, or labeling, so I'm not sure there's any surefire way to do this.  You just gotta know where things are.  

I know, I know... that's so pre-Google, but I suspect it's true of many new content types as they're developed.  Look for more of the same as more new kinds of video, VR, and Augmented Reality images/apps/experiences come online.  They're going to be hard to find.  
I'd love to be wrong about this, but I suspect that's the state of the art for the time being. 

Search on... immersively! 

Wednesday, January 11, 2017

SearchResearch Challenge (1/11/17): Finding immersive experiences

Getting immersed in your topic is usually a great idea... 

... and in the past couple of years, a number of different technologies have emerged that let you record and view 360-degree "immersive" videos.  Here's a nice example from David Hsieh:  


This is just one of many examples of immersive imagery. 


But you can imagine where my interest lies--how do you search for these things?  

Today's SearchResearch Challenges: 

1.  How DO you find immersive online experiences?  (I've mentioned videos as one way to be immersed.  Are there other ways to get that experience?)  
2.  How can you find immersive experiences by location?  For instance, can you find all of the immersives that are near the Wat Chedi Luang temple in Thailand, especially ones that show the famous reclining Buddha?  For instance, can you also find an immersive that shows you the view from the mountain peak that's about 5 miles (8 km) to the west of the temple?   
Reclining Buddha at Wat Chedi Luang temple, Thailand.

Most importantly for this week--say HOW you found the immersive experiences.  What search terms did you use?  And if you learn any new concepts about immersive experiences, let us know what terms / concepts you now know.  

(Keep in mind we're not looking for holodecks, but immersive experiences that you could plausibly have at home or in the office.)  

Search on... immersively! 




Monday, January 9, 2017

Answer: The phases (and more!) of the moon

So... what's the story here?

Why did all of the NASA missions land on the side facing the Earth? 


It struck me the other day: ALL of the NASA landings on the Moon were all on the side of the Moon facing towards the earth.  Why did they neglect the other side?   Was it a kind of strange conspiracy?


Not my photo, but very similar to what I saw on Jan 1, 2017. P/C NASA

The US sent six missions to the moon (Apollo 11, 12, 14, 15, 16, 17).  Here's the map of the landing sites I found with the query:  [ Apollo landing sites map ] 

Apollo landing sites. P/C NASA
 Given this background, our Challenges for this week start with this question of "why only on one side?"    
1. If you look at a map of the Apollo landing sites, they're all visible from Earth--none are on the back side (that is, the side of the moon that faces away from the Earth).  Why were all of the landing sites on THIS side?  (You'd think the back side would have been more interesting.Why didn't we go to the back side?
  
I thought about different strategies for this search, and started with: 

     [ nasa landing sites on the earth-facing side of the moon ] 

I used these terms in a long query because I wanted fairly specific documents (in particular, ones that would use words like "landing sites").  I used the phrase "earth-facing" because I wanted documents that included that terminology (and not "dark side of the moon," which I already knew many people get wrong... there is no dark side, except in albums by Pink Floyd).  

This query worked reasonably well, and I (like others) found the Quora discussion "Which side of the Moon did the Americans land on?"  Although I'm always suspicious about QA (Question-Answering) sites, this post looks pretty good.  It has lots of citations, illustrations, and it's easy to go from this Quora page to NASA web pages that say why they landed on the near (visible / earth-facing) side:  They needed constant communications access, and terrestrial radios don't make it to the other side of the Moon.  

And, of course, NASA had much better imagery of the Earth-facing side, the better to plan the missions.  

Regular Reader Jon found the Quora site with the query: 

     [apollo missions did not land on the far side because]

While Ramón used: 

     [Why Apollo missions never went to dark side of the moon]

Both of these queries are fairly long, but include words that are important for getting the right kind of results.  We're searching for a complex concept--I'm not sure you could succeed with a much shorter query.  

After checking out a few other links on the SERP, I was pretty convinced that this was the story.  

However, Regular Reader (and professional library) Debra and her colleague Anne did something much better--they limited their search to site:.gov and found some NASA documentation of their site selection process. In their words: 

"...We didn't think this was definitive enough so we did an advanced search limiting our search to .gov sites { using [ site:.gov ...] }and got this result {a document on the } Operational Constraints on Landing Sites.  It gives a very detailed explanation of why the landings needed to be on the near side - radio communications were key as was having some knowledge of the topography, and much more was known about the near side than the far side.  
This second article also points out to how the site was selected - NASA definitely wanted to know as much about the site as possible and the near side was what they had information on..."  
These days, of course, we have superb lunar images thanks the the Lunar Reconnaissance Orbiter (LRO).  You can check out these fantastic images at the LRO image archive site. This is sufficiently high-res that you can see the trails (and debris) left by the astronauts.  


 LRO image of the Apollo 11 Landing Site 

The LRO took this beautiful image of the Apollo 11 landing site in 2013 at 24 km (15 miles) above the surface. 

You can see the remnants of their first steps as dark regions around the Lunar Module (LM) and in dark tracks that lead to the scientific experiments the astronauts set up on the surface. The Passive Seismic Experiment Package (PSEP) provided the first lunar seismic data, returning data for three weeks after the astronauts left, and the Laser Ranging RetroReflector (LRRR) allows precise measurements that can be collected to this day. You can even spot the discarded cover of the LRRR.  If you happen to have a large telescope and a gigawatt laser, you can still use the LRRR to measure the distance to the Moon.  (If you're curious about how to do this, check out this episode of Mythbusters where they visited the Apache Point Observatory telescope and bounced some green laser light off of the LRRR. For details about Apache Point, check out the APO website.) 



2. Every so often I'd sketch out the moon as I saw it in the night sky.  Once, when I was looking at several of my sketches together, I noticed that some of the craters on the Moon's edge seemed to be in slightly different places. Huh? I know that the Moon always has the same face pointed to us, but when I looked at my sketches, it would seem that it's not always exactly the same face--especially near the edge. Why would the Moon's face be slightly different during different times of the lunar month? Is it always showing us exactly the same face at all times? 
That same Quora article about why all of the missions were on one side ALSO gave a hint about this second question as well.  In his post, Robert Walker says "Of course no part of the Moon is in permanent darkness. But we always see the same side of it, and at full Moon we see it at full phase. Actually, we see a bit to either side because of lunar libration..."  (emphasis mine)  That's an intriguing thought--that perhaps the Moon really does wobble a bit, and doesn't show us exactly the same face at all times.  

From here, a search for: 

     [ libration ] 

leads to all manner of useful results.  (It's one of those rare words that seems to have no other meaning, but just the Moon-related one.) 

Here's a wonderful YouTube video from NASA showing what libration actually is, the "rolling" of the Moon in the night sky, exposing and hiding different parts of the Moon throughout the month.  This is why my sketches sometimes had significant craters in slightly different places on the Moon's surface.  


This is such a beautiful video, it's worth clicking on the YouTube logo (in the lower right) and watching this at full resolution.  It makes the rocking and rolling motion really obvious. The Moon ends up rolling enough in its orbit that 59% of the total surface area is shown to the Earth during the month.  


Search Lessons 


I take note of 3 things in this week's discussion.  

1. Long queries sometimes work quite well, especially for complex concepts.  All of the queries that worked well for this Challenge ended up having a fair number of words in them.  The Challenge concept was fairly complex (having to do with the Moon, the choice of landing sites, and the earth-facing side of the Moon), so it's not a surprise that we need a fairly long query to get to the right results.  Since this was a complex Challenge, I was prepared to do many alternatives to my original query, but it turned out that the Quora forum discussion was reachable by many different queries.  

2. QA sites are not always low quality!  I subscribe to the Quora posts and get to see the original questions as they fly by.  They are not necessarily deep or well-thought-out questions.  But, on specific topics, the discussion can be very rich and deep.  This one (why NASA landed on the earth-side of the Moon) was especially good.  Don't skip over the QA results, but check them out (and, as always, double-check--second source anything you learn from them).   

3. Searching for official government documentation about a process (by using a site: restriction) can be a great thing. I was impressed by Debra and Anne's strategy of searching for an original process-describing document.  I should have known that NASA (of all organizations in the world) would have published such a thing.  They found it with a brilliant search strategy (to wit, realizing that such a document might exist and then using site:.gov to search the US government's repository).   



Search on, in the spirit of the Apollo missions!  

Sunday, January 8, 2017

Update: More about the Farallons -- "What IS that below?"

A while ago we had a... 

post about whether or not one could see the Farallon Islands from the shore (they're 27 miles to the west off the coast from San Francisco)... 

We answered that yes, you could see them, but your eyes would have to be 489 feet in the air. 

And that's true. 

...HOWEVER... 

It turns out that this is the height you'd need to be to see the islands at sea level.  

In other words, if you wanted to look at the waves crashing on the shores of the Farallons, you'd need to be 489 feet up.  That was what we calculated, and it's still correct.  

It just so happened that I went to San Francisco a week ago, and I went to check this out.

Surprise!  I learned something.  

The Farallons are mountainous islands; they stick up out of the water by quite a bit!  Our calculations didn't take that into account! 

In particular, Southeast Farallon Island (SEFI) is the largest island, with an area of 95.79 acres or (0.14970 square miles or 0.3877 square km).  The island is pyramidal in shape and 357 feet (109 m) high.  In the middle, Seal Rock (Saddle Rock), is around 80 feet (24 m) high, while Aulone Island and smaller Great Arch Rock (Arch Rock) are immediately north of the northern tip of SEFI, and are 350 feet (110 m) in height.  

From my car in the parking lot at Sutro Baths, around 250 feet (76 meters) high, I took the following photo.  



I was happily surprised to see the Farallons on the horizon.  Fantastic!  

Here's a zoom on this image: 


As you can see, SEFI is clearly visible, as are Aulone Island and the Great Arch Rock (which blur together in this image).  You can barely see a ripple of the islands between them.  Here's the satellite image from Google Maps.

The Farallons, seen in satellite view on Google Maps.

And here's the 3D view on Google Maps, as seen from the parking lot (very near where I was standing).  



I have to admit being a bit surprised.  Yes, they're clearly visible, but I didn't think they would be visible from the parking lot--it's only 250 feet up. 

But I'd forgotten that the calculation we made was to the island at sea level, and not to the top (or middle) of the island.  


Search Lessons 


This is yet another reminder that: 

A. It's really worth checking ground truth every so often.  Because...  
B. You find out more about what the question REALLY is all about, and not just what you might think it is.   
 I learned something really useful here.  When you're making basic geometrical calculations, it's handy to really look at your diagram to see if it represents what you think it does.

Remember the diagram? 

Here's the original diagram: 



If I would have looked at my own diagram, I would have realized that I was calculating the angle to the tangent.  The reality is more like this: 

When I took the photo, I was only at 250 feet high... but the islands stand another 375 feet high out of the water!  

I will leave the calculation of how much of the island you can see to the interested reader.  (It's not hard, given what's in the earlier post.)  

As your grade school math teacher probably told you:  "Check your work!"  

She was right.  

Happy to find an error (and correct it)! 

Searching on... 


Wednesday, January 4, 2017

SearchResearch Challenge (1/4/17): The phases (and more!) of the moon

On January 1st, the moon was glorious on the horizon... 

... there it was... a beautiful slender crescent that hung in the western night sky just after sunset.  


Not my photo, but very similar to what I saw on Jan 1, 2017. P/C NASA

I spent a bit of time in rapt contemplation, and then started wondering... 

The US sent six missions to the moon (Apollo 11, 12, 14, 15, 16, 17).  And I remember reading the location of each landing, and then looking at the moon to locate exactly where the landers were located. Once upon a time, I knew the major craters of the Moon very well--I knew their shapes and locations like the back of my hand.  


Apollo 11 astronaut and foot pad of the lander.  P/C NASA


We all know that the Moon is a big sphere.  But it didn't occur to me until just now that the landings all just happened to be on a part of the Moon where I could see them?  Was this just clever publicity and mission planning to make their landing spots visible to the public?  

Once you get curious about something, it's hard to stop.  This line of thinking leads me to our Challenges for the beginning of 2017.  Can you figure them out? 


1. If you look at a map of the Apollo landing sites, they're all visible from Earth--none are on the back side (that is, the side of the moon that faces away from the Earth).  Why were all of the landing sites on THIS side?  (You'd think the back side would have been more interesting. Why didn't we go to the back side?
2. Every so often I'd sketch out the moon as I saw it in the night sky.  Once, when I was looking at several of my sketches together, I noticed that some of the craters on the Moon's edge seemed to be in slightly different places. Huh? I know that the Moon always has the same face pointed to us, but when I looked at my sketches, it would seem that it's not always exactly the same face--especially near the edge. Why would the Moon's face be slightly different during different times of the lunar month? Is it always showing us exactly the same face at all times?  

Both of these questions require a bit of thinking (rather than just search skills).  You'll need to do a bit of research and critical thinking to get to the answers.  

Can you answer these Challenges about the Moon?  

Search on, in the spirit of the Apollo missions!  



Monday, January 2, 2017

Answer: A few Natural History Challenges (ears, embryonic nutrition, and virgin births)

SearchResearch is often a process...  

You start with an observation--maybe you notice that something doesn't quite fit, or maybe there's a missing bit, or a strange misalignment.  

I often write these observations in my notes, and when I have a bit of time (usually on Sunday morning before the sun comes up), I try to find answers.  Some of those notes are questions that I've read about, or small curiosities that have occurred to me as I read.  I try to frame those curiosities as questions, most of which I spent at least few minutes trying to answer.  (This is a great meta-learning strategy: As Richard Feynman pointed out in his description of his learning method, IF you can write your notes as though you were going to teach someone this concept, you'll almost certainly learn it yourself.)  

These Challenges spring straight from my notes, starting with a curious event that happened one morning.  As I walked outside to pick up the newspaper one chilly morning, a flock (or a murder) of crows was hanging around in the front yard tree. I tossed the paper up close to the house, and when it landed, it just happened to make a loud noise, startling the crows into flight. As once flew past me I happened to notice that I didn't know how they heard the noise. "Crow's ears..where?" is what I wrote in my notes.  And hence... 



1. We see birds all of the time, and I know they can hear, but I can't help but wonder: Where are their ears?  What does the ear of an owl or crow look like?  
This isn't a hard Challenge... but it's a surprise to learn what a crow or owl ear looks like.  

     [ crow ear ] 

I happened to see the ScienceAlert article as the very first hit.  ("This is what a crow's ear looks like, and it's freaking us out.")  

It turns out that while they do lack external ears ("pinnae"), crows (and all other birds) have a hole in the side of their head that opens up to the outside world.  This photo is from the ScienceAlert article (which is a frame-grab from the video of someone brushing aside the feathers to expose the crow's ear).  
P/C ScienceAlert (originally from mike_pants/reddit) 

If you do the same search for an owl's ear, you'll find it's very similar: 

The ear of a Northern Saw-Whet owl. P/C Jim McCormac. (He has even more remarkable owl anatomy photos on his site.) 

Bird ears are sometimes easily visible, such as on birds that have no head feathers.  My favorite (for its elegance in flight and ubiquity in California) is the turkey vulture.  Here it's easy to see their ears: 


And unlike mammals, the internal anatomy of bird ears is relatively simple, with only a single bone (the collum) connecting the ear drum (tympanum) to the cochlea.  

A sketch of the internal anatomy of the crow's inner ear, showing the single bone
connecting the eardrum to the cochlea.
P/C Watcher, who has a wonderful post about bird hearing.  
And as Ramón pointed out, some owls have Ear tufts.. and they are not ears

[owl ear location]

The ears are located at the sides of the head, behind the eyes, and are covered by the feathers of the facial disc. The "Ear Tufts" visible on some species are not ears at all, but simply display feathers.

2.  As you know, mammal embryos depend on a placenta for nutrition via their mother until birth. Egg-laying animals provide a yolk for their embryos for feeding until hatching.  But I've heard about a few other ways in which some animal embryos get nutrition while still in utero that's from a surprising source.  What are three other strategies for embryos to get nutrients while still in their mother's uterus?   
To start this search, I did the search: 

      [strategies for embryo nutrition without placenta ] 

which leads to a number of fascinating sources, including an article on tiger sharks where the embryo grows in a uterus that's filled with a nutritious fluid, but with pups that do not have a placental connection (and an egg yolk that is too small to let them grow to maturity).  This strategy for feeding embryos is generally called matrophagy (feeding from the mother). 

Their experiment demonstrated that this liquid, which they have termed, embryotrophe (literally “embryo food”) is the major source of nutrition for tiger shark embryos. The weight gains they found for the fertilized eggs as they grew into full-term embryos, was as high as 2119%.

Another article in that SERP tells us that Mammals are not the only animals to feed embryo during gestation

Much to my surprise, this article tells us that: 
"By comparing the examples of matrotrophy with the placement of species on the DNA-based tree of life, the authors propose that matrotrophy has evolved independently in 140 or more different animal lineages, and is often associated with live birth. According to the study, previous work scattered through the specialized scientific literature had talked about matrotrophy in many invertebrate groups, but it had never been appreciated just how common it might be, and how frequently it had evolved. There are more species of flatworms that employ mother-feeding than there are species of mammals!"  
And it goes on to tell us about cannibalism of sibling eggs or other embryos in the uterus for tiger sharks.   

This was a bit of a surprise.  To get more detail on this, I did a search for: 

     [  sibling egg eating in utero ] 

This lead me to a Smithsonian Magazine article about in utero egg-eating (and in utero cannibalism)

When an embryo eats eggs to grow, that's called oophagy. I also learned the word adelphophagy (literally, eating your brother), both of which are handy terms to know.  Doing a search for: 

     [ oophagy adelphophagy ] 

leads to the book:  The Physiology of Developing Fish: Viviparity and Posthatching Juveniles (Hoar & Randall, 1988), which tells us more about in utero cannibalism (dates! weights! times!) than you might ever want to know.  Fascinating reading.  (And a YouTube video, should you want to see tiger shark embryos being consumed by their larger siblings...)  

Bottom line: the three in utero nutrition strategies I found are: 

1. oophagy - eating other eggs produced by the mother
2. adelphophagy - eating other sibling embryos
3. matrophagy - producing a nutritious fluid that the embryos ingest

3. Speaking of giving birth, I read that virgin births are fairly common in certain kinds of animals.  Can you find which vertebrates are able to give birth without having to bother with all of the process of finding and joining with a mate?  
The obvious query: 

     [ virgin birth in animals ] 

leads to a wealth of results... and a specific term to use in additional searches: parthogensis.  It's easy to find 20 species of snakes, Komodo Dragons, domestic chickens, sawfish, sharks, and many kinds of lizards.  These virgin (parthogenic) births can produce fertile offspring. 

And, most surprising of all, some lizard species (e.g. Aspidoscelis genus of whiptail lizards) seem to be all female.. meaning that for these lizards, males are simply so much excess baggage.

So not only does virgin birth happen, it's fairly common!    



... and it's easy to find many species that do so.  

Search on into the New Year!