News aggregator

Long lines and lots of instruments

Sugar - Tue, 03/25/2014 - 11:38
If you want to image the Earth’s crust and upper mantle with seismic data, you need to record the arrival of seismic waves that have propagated down to, in our case, depths of up to ~30 km.  These deep-diving phases travel quickly through the denser, higher velocity rocks of the lower crust and upper mantle, and they arrive back at the surface ahead of shallower phases at long source-receiver offsets (see video below).  

To record these lower-crustal and upper-mantle phases as “first arrivals”, where they are not obscured by the arrival of energy from shallow paths, we use long lines.  Long lines mean lots of receivers and lots of driving to deploy and recover these instruments.  We could have used lots of sources instead, but the blasts we used to get seismic energy into the lower crust and upper mantle in this experiment take a lot of time and money to setup.  Receivers are much cheaper, so we used a lot of them.  (For similar wide-angle/long-offset work at sea, airgun sources are cheaper than putting seismometers on the seafloor, so we use many shots and a smaller number of receivers out there.)

This time-lapse video shows Team 13 of 14 recovering 89 of the 1200 total short-period seismograph stations from where our line crossed Fort Benning, near the northwestern end of the line.

Nathan Miller, LDEO

Deploy in the rain, recover in the sunshine…

Sugar - Tue, 03/25/2014 - 00:32

Weather map during deployment.
When the time came to install our 1200 small seismographs across Georgia at the flagged positions, the rains came….   A lot of rain.  During our first deployment day, we received 1-2 inches of rain, and another wave of rain clouds came through on Day 2 (check out map). Roads that used to be easily passable became mudholes or were flooded with water. All-wheel-drive vehicles and drill rigs alike got stuck, and a few station locations could only be reached on foot. Our hard-working field crew labored in the rain digging holes and deploying seismometers.  Vehicles, equipment and people were covered in the famous Georgia red clay (and other muds and sands of Georgia and northernmost Florida). Adding insult to injury, problems with the programming of some of the instruments meant that we actually had to pick up and redeploy many of them. It was a mudbath.  Nonetheless, our field crew managed to deploy 1200 seismometers across Georgia by Tuesday at sundown. It was an impressive show of endurance, and an inspiring display of positivity given the number of people that were still smiling and upbeat at the end of it all. 
A couple of days later, after our seismic shots, it was already time to pick up the instruments, and the weather changed completely.  The sun shined on SW Georgia, and we picked up almost every last seismometer in just one day under blue skies….  
Donna Shillington, LDEO

Video of shots L1-05, 06, 07 and 08

Sugar - Sat, 03/22/2014 - 22:52
Shooting a land refraction experiment is more difficult in almost every way than collecting a comparable dataset at sea.  Far more difficult.  But I can't think of anything at sea that compares to the experience of setting off a series of shots at night.  On the first night of shooting, Steve, Nathan, Meghan and I detonated shots L1-05, 06, 07 and 08, while Galen, Donna and Natalie shot 14, 13, 11, and 10, and Tina, Adrian, James and Semir shot L1-04.  I recorded the video clips linked below at our shots (05-08).

To someone who hasn't seen a seismic source shot before, there really isn't a good way to describe what a good shot feels like, except as something you haven't felt before.  We had a number of students watching L1-05 being shot, since this location is quite close to Americus.  The video of L1-05 is completely lacking in drama, which is a good thing; but that shot gave us all a great ride.  The 100 pounders 06 and 07 were also surprisingly good.

We made gathers for most of the shots today. The dataset is fantastic, and 05, 06 and 07 produced super record sections.  L1-08 committed most if its energy to the air, but it shook the ground nicely and I've got a feeling those data are going to be great too.

The video is here:


Sea Change

Geopoetry - Fri, 03/21/2014 - 10:06


Gliders and buoys and robots — oh my!

Over and through the ocean they fly.

Oodles of data from sensors galore,

Studied by many, far from the sea’s roar.

A real revolution, there seems little doubt,

But what of the crew who never sail out?

To peer in the great briny main without drinking …

How might that impact the next wave of thinking?


Further reading:

A Sea Change for U.S. Oceanography, Science 2013

The New Generation of Sea Scientist, Science 2013

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. First posted 3/1/13 on Allen’s website.

Random Pictures from the Road (and otherwise)

Sugar - Wed, 03/19/2014 - 13:43
As a follow follow up to Chastity's post, I thought a few random pictures from the road would be entertaining. I have been part of group 5 and as such responsible for the part of the line that spans from Hahira in the south to just north of Adel.

 South-central part of the seismic line. The yellow line is team 5's section.  We have been in a relatively rural part of Georgia and as a result have not encountered many locals save a few who have stopped to ask if we are ok. However, we have seen quite a few interesting things that are quite out of the ordinary (to me at least).

Friendly Muscovy duck.Rocks in a stream bed with associated pink spongy material (?)
Spanish moss.Linguoid (current) ripples on a washed out road. We have also seen quite a few old abandoned farm houses in various stages of aging...

At least 10-15 dogs were standing guard at this house, including about 8 puppies.

Caroline making some new friends.
All said we have dug 122 holes in team 5's stretch. We have also helped deploy instruments in other sections as well and while doing so have seen others hard at work.

Meghan and Nate getting it done!Along the way the cars have taken quite a beating and have actually held up pretty well. Although there have been a few instances where people got stuck, I think that the people with the toughest job will be the guys that have to detail the cars upon their return...

A more appropriate vehicle (?)And lastly here's a couple more random pictures that I thought were interesting.

The large disparity in fuel grade gas prices.
A ~perfectly leveled geophone (it's harder than you'd think).Hopefully this random selection of pictures was entertaining. Up next we will post about last night's "shots." In the meantime, I can say that they were all successful with varying degrees of excitement. The most important thing is that all of our hard work is being realized as the instruments are recording refractions from buried geology that will help us unravel some of the mystery that surrounds events that happened in this area long ago.

James Gibson, LDEO

Rain, geophones, and animals … Oh my!

Sugar - Tue, 03/18/2014 - 17:15

Chastity Aiken
Georgia Institute of Technology

Flags, Flags, and More Flags - Locating the sites for 1200 instruments

Sugar - Sat, 03/15/2014 - 23:14
Many of the SUGAR field team arrived in Americus, GA on Wednesday to start helping with the massive charge of deploying 1200 seismic instruments along the SUGAR seismic line.  The seismic line spans 200 miles from northwest Georgia to just past the Georgia-Florida border; a 4+ hour car drive from end to end!  Everyone gathered early Thursday morning on the idyllic Georgia Southwestern State campus to meet with the chief scientists and learn about the proper techniques for identifying installation sites for the seismographs (just the first step in installing the instruments).  With neon orange safety jackets, numerous maps, GPS devices, packets of official permitting documents, and heads full of safety precautions the field team split into seven two-person pairs each equipped with their own squeaky clean rental car (though they didn’t stay clean for very long!).  
The fleet of SUGAR rental cars looking clean and shiny before being driven
into the field where they undoubtedly got a little mud on their tires.
Each pair of field assistants was given a segment of the seismic line to drive and flag locations for instrument installation deemed safe both from the seismograph (i.e. dry, firm soil) and the install team (i.e. a safe distance from the road).  Given the shear distance of the seismic line, teams found themselves amid diverse backdrops from rolling farmland with overly friendly cows to buzzing residential neighborhoods to sandy stretches flanked by towering groves of Ponderosa Pine trees. 
Antonio placing a flag and using a GPS device to note the location where a
seismograph will be installed amid the sandy surroundings of a Ponderosa Pine farm.
Every team was able to flag all their sites within just two days leaving us the luxury of a sunny Saturday morning free for exploring more of our beautiful Georgia surroundings.  Next up is the actual task of installing the 1200 seismographs which will involve twice the people, six more (temporarily clean) vehicles, and of course countless exciting adventures from the field.  Happy (almost) St. Patrick’s Day from Americus!
A picturesque county road near Jasper, FL along which instruments will be deployed.
-- Natalie Accardo, LDEO

A day with the seismic source team in photos

Sugar - Fri, 03/14/2014 - 23:43
The source of sound waves for the SUGAR experiment will be a series of controlled blasts along the profile.  For each of these, we drill a 60-100 ft deep hole, place emulsion explosives with boosters and caps at the base of the hole, and fill in the rest of the hole with dirt and gravel.  Each seismic source location requires a substantial amount of work by drillers and the UTEP seismic source team.  Below, Adrian Gutierrez shows a day in the life of the source team with pictures (Donna Shillington, 13 March 2014)

Adrian Gutierrez, 13 March 14
7:30 am: Leave Georgia Southwestern State University, where we are staying, and head to the site8:20 am: Arrive at site 8:30 am: Start drilling and take geological samples every 5 ft.

9:00 am: Dyno Nobel truck arrives; load emulsion into cut PVC pipe sections that serve as a holders for emulsion.
9:30 am: Surprise visit from other scientists on the project9.50 am: Setting up the booster in the emulsion.11.20 am: Loading the explosives into the drill hole12.00 pm: Drill crew starts removing their equipment12.45 pm: Tagging the charges and plugging the hole3.15 pm: Move onto the next drill site.Nighttime: Finally back to the dorm.

The Dawn of Plate Tectonics

Geopoetry - Fri, 03/14/2014 - 12:30
 Dr. Mark Reagan, Science Now

Image: Dr. Mark Reagan, Science Now

An ancient grain of zircon found

In Jack Hill sandstone north of Perth,

Inside its crystal lattice bound:

Secrets of our planet’s birth.


The oldest grain (we rock hounds swoon),

Tells of magma oceans past,

An early impact yields the moon;

And all of this occurred so fast!


The zircon’s old, which then implies

That solid rocks must be still older.

In Canada, a sequence lies,

With implications even bolder!


A pattern locked within old lava

Echoes patterns from the deep;

Mariana-like subduction …

To plate tectonics, take the leap!


Hadean times are cloaked in intrigue,

Eons distant, full of strife,

Yet it seems these rocks held promise,

Full of boron, primed for life!



In the news:

New Record for Oldest Earth Rock, Sky and Telescope

Hadean age for a post-magma-ocean zircon confirmed by atom-probe tomography, Nature Geoscience

The Dawn of Plate Tectonics, Science Now

Heading down early on? Start of subduction on Earth, Geology

Arrival of the seismic equipment!

Sugar - Tue, 03/11/2014 - 19:57
Boxes with seismographs and other equipment
During this project, we will deploy 1200 small seismographs along a 200-mile-long (300-km-long) profile across Georgia.  All of these seismographs were shipped to Georgia from Socorro, New Mexico. This is the headquarters of the Incorporated Research Institutions for Seismology (IRIS) Program for Array Seismic Studies of the Continental Lithosphere (PASSCAL), a facility that provides seismic instrumentation to US researchers.  It takes a lot of boxes to hold all 1200 seismographs and the associated equipment and tools.  There are 15 seismographs per box, so that's 80 boxes alone without counting boxes for geophones, etc. 

Fortunately, we have a lot of space! Our field headquarters is located in a historic gym on the campus of Georgia Southwestern State University in Americus, GA.  Faculty and staff at GSW have been extraordinarily generous with their time and expertise. They are allowing us to use the Florrie Chappel gym as our base of operations, and they have helped us enormously with Georgia geology and logistics coordination, handling our huge shipment of equipment and supplies, housing on the campus (many of us are staying in one of the dorms!), setting up the gym with internet access, power, and tables, and much, much more. Today, they moved all of the boxes with our seismic equipment from the shipping warehouse to our field headquarters in the gym. I can sense that all of our seismic instruments are itching to be deployed....
Pallets waiting outside the Florrie Chappell gym
Donna Shillington
11 March 2014

More preparations: mini seismic experiments

Sugar - Mon, 03/10/2014 - 11:31
A geophone in grass, awaiting sound waves.

To prepare for our big seismic experiment, we have collected a couple of miniature seismic datasets.  The shallow geology varies substantially along our profile and is very important for planning the depth of drilling and size of our seismic sources. In particular, we need to determine the depth to a limestone layer in a few places.   The same seismic method that we will use to understand the deep geological structures beneath Georgia can also be used at a smaller scale to examine layering in the upper ~100 ft (~30 m) beneath the surface. We recorded the data on 24 geophones attached to a 230-ft-long (70-m-long) cable.  The source was a modified shot gun that looks like a pogo stick.  We drilled small holes in the ground, loaded the gun and stuck it in the hole. To limit the kickback, we weighted the gun down with a metal plate topped by two heavy jugs filled with sand. Hit the plate with a mallet and – BANG – a seismic source! Not a bad way to spend a sunny Sunday!

Check out Dan firing the seismic source...

Donna Shillington
9 March 14

Cold Facts

Geopoetry - Fri, 03/07/2014 - 08:00
oil fields, North Dakota

Satellite view of oil fields at night in North Dakota. Photo: NASA/NPR

Satellites cast their wide gaze

At night, on the bright Bakken blaze;

Bright as a large, sparkly city,

Up close, it’s not quite as pretty.

What fate might this appetite bring?

In government halls, squabbles ring.

Key to the carbon debate

Is the last Termination’s change rate.

What’s our scenario worst?

Was warming or CO2 first?

New ice core studies profess

A 200-year lag — or less.

A puzzle to solve ere we burn:

The process of compacting firn.


Further reading:

Synchronous Change of Atmospheric CO2 and Antarctic Temperature During the Last Deglacial Warming, Parrenin et al., Science 2013

Leads and Lags at the End of the Last Ice Age, Brooks, Science 2013

Study of Ice Age Bolsters Carbon and Warming Link, Gillis/NYT 2013

A Mysterious Patch Of Light Shows Up In The North Dakota Dark, Krulwich/NPR 2013

The New Oil Landscape, Dobb/National Geographic 2013

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. First posted 3/1/13 on Allen’s website.

Laying the groundwork

Sugar - Wed, 03/05/2014 - 22:56

We have just arrived in sunny Americus, GA from the cold north to ramp up for the SUGAR project. The peaceful, pastoral landscapes of southern Georgia mask geological structures created by a series of dramatic events that were central to the formation of the North American continent.  During SUGAR, we will use sound waves to image these geological structures.   Less than 2 weeks from now, we’ll deploy 1200 small seismographs along a 200-mile-long line that extends from north of Columbus to south of Valdosta with the help of a cadre of students from across Georgia and beyond. These instruments will record sound waves generated by a series of controlled blasts in deep drill holes.

Spanish moss lined trees along our transect south of Valdosta
Collecting these data will involve a week of intense work by >30 people. However, just laying the groundwork for this effort has already required a long list of (sometimes novel) tasks.  When we conceived of this project, we drew a couple of straight lines on a map that would enable us to capture the geological features that we wish to study: the South Georgia Basin, the Suwanne Suture, and frozen magmas from the huge Central Atlantic Magmatic Province.  In reality, we must create this line by knitting together a patchwork of roads.  During a couple of planning trips, we bumped along on dirt roads, cruised county lanes, and zoomed down state highways mapping out the best route. 

Dan and Steve scouting our route. Our seismometers will line county and state roads across southwestern Georgia, and both seismometers and seismic sources will cross private properties. Identifying private landowners to request permission has transformed us into detectives. In most cases, the name and address of the owner are easily found on the tax assessor's website for each county.  But actually getting in touch with people is not so easy! We mailed letters. We put flyers directly into people’s mailboxes. We searched for phone numbers online and left messages (sometimes multiple messages…). We found websites and email addresses for companies, and sometimes wrote to people about our project through website forms (including those for a bank, a dentist's office and a website selling organic beef!).  Happily, once we made contact, individuals and companies have been very welcoming and graciously granted us permission – southern hospitality in action!  A litany of other preparations have already been completed or are currently underway. Drilling of the holes for seismic sources has just begun, and the seismometers will arrive very soon. We are definitely ready for the transition from preparing to doing....
Donna Shillington
5 March 2014

Solar Heartbeat

Geopoetry - Fri, 02/28/2014 - 08:00
 from Charboneau and Smolarkiewicz, Science 2013

Image: from Charboneau and Smolarkiewicz, Science 2013


Upon our little spinning rock,
Cosmic rays and debris knock.
Through great fields and waves we race,
Not empty, our broad path through space!
We’re touched, long fingers from afar:
Energy from our bright star.
A fusing, roiling dynamo,
Magnetic fields induced by flow.
Eleven circuits round our wheel,
Her heartbeat’s pulses we can feel.
In search of answers, models run,
Probing rhythms of the sun.


Further reading: Modeling the Solar Dynamo, Science 2013

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. First posted 4/5/13 on Allen’s website.

Shag, Before It Was Cool

Geopoetry - Fri, 02/21/2014 - 14:20
woolly rhino

Science, 2011

More cuddly than a dino,
The Zanda woolly rhino!
This pioneer of old
Grew shag before the cold.
The high Tibet plateau
Was higher then, you know!
And when the ice expanded,
(with you I will be candid):
They did some procreation
And made a woolly nation!
We still have some Tibetan yak …
But I want that rhino back!


Further reading: Out of Tibet: Pliocene Woolly Rhino Suggests High-Plateau Origin of Ice Age Megaherbivores, Tao Deng et al., Science 2011

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. First posted 9/2/11 on Allen’s website.

Global weirding?

Geopoetry - Fri, 02/14/2014 - 15:12

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Mountains of snow line the street,

And some days I envy a beard.

Ask any shoveler you meet –

The weather this winter is weird!


How strange is it, really? Some wonder,

If sea-ice melt unleashed the Vortex.

Has warming torn systems asunder;

Should we invest big in Gore-Tex?


We’ve been gripped by deep-freeze before;

Sometimes it’s just wicked cold.

The overall trends worry more:

How will it be when we’re old?


Thermostat’s tending to heat;

We wait as the sea gently rises.

Our future we surely will meet,

And always, we’ll get some surprises.


Photo Credit: Figure generated by Cameron Beccario (EARTH.NULLSCHOOL.NET); Results sourced from the NCEP/NOAA Global Forecast System

Further reading:

A letter in Science Magazine: “Global Warming and Winter Weather”

Maps of recent temperature anomalies: Climate Reanalyzer, University of Maine

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. Visit Allen’s website for more.


The Story at the Bottom of the South China Sea

Opening the South China Sea - Mon, 02/10/2014 - 10:17

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Trevor 2

Sediments drilled from beneath the South China Sea are a window into the region’s past geology and climate. (Bill Crawford/IODP)




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We have drilled 2,600 feet below the sea floor and in another 500 feet, will reach the crystalline igneous basalt of the ocean crust. Though finding the age of the basalt is our main aim, the thick sediments that overly the crust also have a story to tell. As the sediments build up over time, they record the geological and climate history of the region.

There are the muds, silts, and sands, shaken loose from shallower depths and transported by gravity down-slope to the deep basin, where our first drill site is located. Ultimately, these sediments come from erosion of the surrounding land, and in this tectonically active part of the world, there is a lot of erosion going on. The island of Taiwan, for example, is being tectonically uplifted at a rate of about 0.2 inches per year, and is being eroded at about the same rate. This may not sound like much uplift, but imagine a world without erosion, Taiwan would stand 12 miles high after 4 million years. All that eroded rock ends up on the seabed, and some of it may find its way to our site.

There are the tiny shells of foraminifera and coccolithophores (familiar to us as chalk, in their pure rock form). They form a continual rain from the sea surface, and build up slowly but steadily on the seabed. The overturn of marker species shows us the age of the sediments, and their chemistry carries a record of ocean temperatures in the past.

Finally, there are volcanic sediments – from thin ash layers from distant volcanoes, to thick beds containing coarse chunks of rock exploded from nearby volcanoes. The close volcanoes are no longer active, and some have sunk beneath the sea to become seamounts. We will know from the depth of these beds in the sediment succession when the volcanoes erupted and for how long they were active.

This diversity means there is always something new and interesting to see in each 33-foot-long core that comes up from the sea bed, each another chapter in the geological history of the South China Sea. Among the 32 scientists on board, we have specialists in sedimentology, micropaleontology, volcanology and other fields. We are an international group; about half of us hail from China, a quarter from the U.S, and the rest from Australia, Brazil, France, Switzerland, Japan, Taiwan, and the Philippines (so there’s a good mix of music in the core laboratory – very nice). And that’s just the science party – the ship’s crew is almost as diverse.



Geopoetry - Fri, 02/07/2014 - 10:51
 J. Cohen for the photograph of S. crassicornus; P. Herring, P. bifrons; and P. Batson (, C. faurei, from Science 2010

Photos: J. Cohen for the photograph of S. crassicornus; P. Herring, P. bifrons; and P. Batson (, C. faurei; from Science 2010

Out in the ocean, where strange things are growing
(Jellies and fishes and creepies unknown)
You might be surprised how many are GLOWING,
With Halloween faces that chill to the bone.
At twilight depths, where darkness meets light
Life’s a grim game of hide-and-go-seek,
A massive migration when day turns to night,
All eyes are peeled for a peek.
If you’ve got the right stuff (or bacterial friends):
Some luciferin and luciferase,
You can flash, you can glow from your eyes to your ends –
And put on a show to amaze!
“I’m not good to eat,” “I’d like to have sex,”
“You’re blind, now I’ll run away,”
“My belly’s the sky,” and subjects complex,
Such wonderful things you can say!


Further reading: Bioluminescence in the Ocean: Origins of Biological, Chemical, and Ecological Diversity, E.A. Widder, Science 2010

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. First posted 5/14/10 at Allen’s website.

Drilling Deep into the South China Sea’s Past

Opening the South China Sea - Tue, 02/04/2014 - 10:56

SCS mapFive days after leaving Hong Kong, the JOIDES Resolution is on site and drilling into the muds and silts of the South China Sea. The expedition’s main objectives are tectonic in nature, and I’m not really a tectonicist (I’m on board for the borehole logging), so for me this cruise is a crash course in the geological history of this area.

The origin of the ocean crust under the South China Sea is enigmatic, and there is ongoing scientific debate about which tectonic forces pulled apart the crust here to form the basin. In one hypothesis, the collision of India into Asia that built the Himalayas and pushed out Indochina to the southeast had the collateral effect of causing extension to form the South China Sea. The leading rival hypothesis says that the extension resulted from slab-pull from subduction at the southern edge of the basin (Borneo and Padawan). Of course, there are theories that mix the two, as well as minor-party candidates (plumes!).

The expedition aims to test the competing hypotheses by dating the earliest ocean crust (at the northern edge of the basin) and the youngest ocean crust (close to the now-inactive spreading center). If the age interval of sea floor spreading matches the age of the extrusion of Indochina (lets say 35 to 16 million years ago), then the Indochina extrusion hypothesis gains support; but if we find different ages, other hypotheses will move up the leader board. The debate and this expedition add to our understanding of the basic forces that shape the Earth’s surface.

Until now, the dating and interpretations rely on magnetic sea floor anomalies and other geophysical surveys. We will date the rocks directly for the first time, by argon-argon dating of the basalt that forms the ocean crust, and by the age of the sediments sitting on the basalt. The tricky part is that the basalt lies under 950 meters of sediments at the first site, and under 1850 meters at the second. To drill to this depth and bring back 100 meters of basalt is challenging to say the least, but there is a highly experienced drilling crew on board, so we are in with a shot. I’ll let you know how we get on!

Latimeria Chalumnae

Geopoetry - Thu, 01/30/2014 - 11:52
 Laurent Ballesta/andromede Oceanologie (Science)

The African coelacanth. Photo: Laurent Ballesta/andromede Oceanologie (Science)

Just imagine: one fine day, a fish revealed to you …
With proto-limbs, a monstrous face, all tinged with silver-blue!
Huge and strange and other-worldly, long thought to be lost,
In the flesh (starting to smell!) so many epochs crossed.
The coelacanth! Good Old Four Legs, to some, the “Living Fossil,”
The animal itself is big, its history colossal!
Ms. Latimer, she recognized its weirdness and allure;
Decades later, of its story some things were not sure.
But now we have its genome clear and plain for all to see,
Shedding light on autopods, immune systems, and pee!
More closely tied to humans than to tuna or to trout,
Holding secrets of the beasts who from the sea, climbed out.


Further reading:

Living fossil genome unlocked, Nature News

African coelacanth genome provides insights into tetrapod evolution, Amemiya et al., Nature 2013

First posted 4/19/13 at Katherine Allen’s website.



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