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DATE 2016-12-01

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DATE 2016-12-20
FROM mrbrklyn
SUBJECT Subject: [Learn] Phylogenetic study worth noting
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120240175
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Academic Search Complete

Taking Wing

A remarkable fossil record of the dinosaurs that led to birds reveals =

how evolution produces entirely new kinds of organisms

At about six o'clock in the morning, long before light broke on a cold =

November day in 2014, I pushed through the Beijing station and fought my =

way onto a crowdetd train. I was headed for Jinzhou, a Chicago-sized =

city in the northeastern fringes of China. I tried to steal back some =

sleep as we crawled past concrete factories and hazy cornfields, but I =

was too excited to nod off. Something rumored to be incred-ible was =

waiting for me at my destination=E2=80=94a mysterious fossil that a farmer =
had =

stumbled on while harvesting his crops.

Four hours later I stepped onto the platform in Jinzhou, trailing behind =

my colleague Junchang L=C3=BC, a famous dinosaur hunter at the Chinese =

Academy of Geological Sciences in Beijing who had asked for my help in =

studying the fossil. A small band of local dignitaries greeted us and =

whisked us away to the city's museum, a rickety building on the =

outskirts of town. With the seriousness of a high-level political =

summit, our party proceeded down a long hallway and into a side room =

where a slab of rock perched on a small table. It was then that I found =

myself face-to-face with one of the most beautiful fossils I had ever =

seen: a skeleton about the size of a donkey, its chocolate-brown bones =

contrasting with the surrounding gray limestone.

Clearly a dinosaur, the creature had steak knife teeth, pointy claws and =

a long tail that left no doubt that it was a close cousin of Jurassic =

Park=E2=80=99s villainous Velociraptor. Yet the Chinese specimen differed f=
rom =

such ordinary dinosaurs in important ways. Its bones were light and =

hollow, its legs long and skinny like a heron's, and its body covered =

with assorted types of feathers, including big quill pens on the arms, =

stacked over one another to form wings. This dinosaur bore a striking =

resemblance to a bird.

About a year later L=C3=BC and I described this skeleton as a new species, =

which we called Zhenyuanlong. It is the latest of many feathered =

dinosaurs found in China's Liaoning Province over the past two decades=E2=
=80=94a =

remarkable series of fossils that illustrate, like a flip book, how the =

monstrous dinosaurs of yore transformed into the birds of today.

The implications of these fossils are momentous. Ever since Charles =

Darwin, scientists have wondered how evolution produces radically new =

groups of animals. Does it happen rapidly, the accident of some freak =

mutation that can turn a land-bound creature into a master of the skies? =

Or are these new groups forged more slowly, as organisms adapt to =

changing environments over millions of years? Zhenyuanlong and the other =

fossils from Liaoning and elsewhere are starting to provide an answer.
TRANSITIONAL FOSSILS

birds have a host of features that set them apart from all other modern =

animals. In addition to traits that enable them to fly, they possess =

high metabolisms that allow them to grow incredibly quickly and large =

brains that endow them with high intelligence and keen senses. Birds are =

so distinctive, in fact, that researchers have long puzzled over their =

origins.

In the 1860s English biologist Thomas Henry Huxley=E2=80=94one of Darwin's =

closest friends and most vociferous supporters=E2=80=94began to figure out =
the =

mystery of where birds came from. Just a few years after Darwin =

published On the Origin of Species in 1859, quarry workers in Bavaria =

split open a limestone slab with the 150-million-year-old skeleton of a =

Frankenstein creature inside. It had sharp claws and a long tail like a =

reptile but feathers and wings like a bird. Huxley realized that the =

beast, dubbed =E2=80=9CArchae-opteryx,=E2=80=9D bore an uncanny resemblance=
to small =

flesh-eating dinosaurs such as Compsognathus that were also starting to =

come to light at around the same time. So he proposed a radical idea: =

birds descended from dinosaurs. Others disagreed, and the debate went =

back and forth for the next 100 years.

The question was ultimately settled, as these things usually are, by the =

discovery of new fossils. In the mid-1960s Yale University =

paleontologist John Ostrom unearthed the astonishingly birdlike dinosaur =

Deinonychus in western North America. It had long arms that looked =

almost like wings and a lithe build indicative of an active, energetic =

animal. Maybe, Ostrom surmised, Deinony=C2=ADchus even had feathers. After =

all, if birds derived from dinosaurs=E2=80=94which by now many paleontologi=
sts =

were beginning to accept=E2=80=94feathers must have developed somewhere alo=
ng =

that evolutionary lineage. But Ostrom could not be sure, because all he =

had were the creature's bones. Sadly, soft bits like feathers rarely =

survive the ravages of death, decay and burial to become fossilized.

Ostrom waited. He kept looking for the holy grail that would prove =

beyond any doubt the connection between birds and dinosaurs: dinosaur =

skeletons preserved in the type of exquisite detail needed to document =

feathers. Then, in 1996, as his career was drawing to a close, Ostrom =

was at the annual meeting of the Society of Vertebrate Paleontology in =

New York City when Philip Currie, now at the University of Alberta, =

approached him. Currie, who had also been studying birdlike dinosaurs, =

had recently returned from a trip to China, where he caught wind of an =

extraordinary fossil. He pulled out a photograph and showed it to =

Ostrom. There it was, a small dinosaur surrounded by a halo of feathery =

fluff, immaculately preserved because volcanic ash had quickly buried =

it, Pompeii-style. Ostrom began to cry. Somebody had finally found his =

feathered dinosaur.

The fossil that Currie showed Ostrom, later named Sinosaur=C2=ADopteryx, =

opened the floodgates of discovery. Scientists sprinted to the Liaoning =

region of China where it was found, like prospectors in a gold rush, =

although it was really the local farmers who knew where to look. Today, =

two decades after the discovery of Sinosauropteryx, fossil hunters have =

recovered more than 20 species of feathered dinosaurs from Liaoning. =

They run the gamut from nine-meter-long primitive cousins of =

Tyrannosau=C2=ADrus rex coated in hairlike fuzz, to dog-sized herbivores wi=
th =

simple, porcupine-style quills, to crow-sized gliders with full-on =

wings. They are among the most celebrated fossils in the world.

The feathered dinosaurs of Liaoning clinched it: birds really did evolve =

from dinosaurs. But that statement is perhaps a little misleading =

because it suggests that the two groups are totally different things. In =

truth, birds are dinosaurs=E2=80=94they are one of the many subgroups that =
can =

trace their heritage back to the common ancestor of dinosaurs and =

therefore every bit as dinosaurian as Triceratops or Brontosaurus. You =

can think of it this way: birds are dinosaurs in the same way that bats =

are an aberrant type of mammal that can fly.

The Liaoning fossils have also helped untangle the genealogy of birds, =

revealing where they perch on the dinosaur family tree. Birds are a type =

of theropod=E2=80=94the same group to which ferocious meat eaters typified =
by =

behemoths such as T. rex, Allo=C2=ADsaurus and Spinosaurus belong. But the =

very closest relatives of birds are a subset of much smaller, nimbler, =

brainier theropods: the raptors, which include Velociraptor, Ostrom's =

Deinonychus and the oh-so-birdlike Zhenyuanlong that L=C3=BC and I describe=
d =

in Jinzhou. Somewhere within this flock of feathery species lies the =

line between nonbird and bird.

There are now so many feathered dinosaurs from Liaoning and elsewhere =

that, taken together, they provide the best glimpse at a major =

evolutionary transition in the fossil record. I and other scientists are =

applying a wealth of cutting-edge techniques to these fossils=E2=80=94compu=
ted =

tomographic scans to visualize anatomy, computational analyses for =

building family trees, computer models of how these animals moved, and =

advanced statistical techniques to track how evolution produces new =

species and body plans. Recent insights from these investigations are =

allowing us to piece together the story of how a dinosaur turned into a =

bird=E2=80=94keystone evidence for solving that age-old conundrum of how ma=
jor =

new groups come to be.
ACCIDENTAL LIFTOFF

the origin of feathers is central to the enigma of bird evolution. =

Feathers are to birds what slicked-back hair and sideburns were to =

Elvis. A calling card. One glance at the outstretched wings of an eagle =

or the gaudy tail of a peacock, and you know exactly what you are =

looking at. It must be a bird because unlike mammals, or reptiles, or =

any other groups of living animals, only birds have feathers. And what a =

thing to have. Feathers are nature's Swiss Army knives, multipurpose =

tools that can enable flight, impress mates or rivals, and retain warmth =

and brood eggs while an animal sits on a nest. Indeed, they have so many =

uses it has been hard to figure out which purpose they first evolved to =

serve.

Sinosauropteryx and the other Liaoning fossils make one thing certain: =

feathers did not suddenly spring forth with the first birds but =

originally debuted far earlier, in their distant dinosaurian ancestors. =

The common ancestor of all dinosaurs may have even been a feathered =

species. These earliest feathers looked very different from the quill =

pens of modern birds, however. The plumage of Sinosauropteryx, along =

with many other dinosaurs, looked more like fluff, made up of thousands =

of hair-like filaments. No way could these dinosaurs fly=E2=80=94their feat=
hers =

were too simple to catch the wind, and they did not even have wings. The =

first feathers must have therefore evolved for something else, probably =

to keep these small dinosaurs warm.

For most dinosaurs, a coat of bristly feathers was enough. But one =

subgroup=E2=80=94the maniraptoran theropods=E2=80=94went for a make-over. T=
he hairlike =

strands grew longer and then started to branch, first into a few simple =

tufts and then later into a much more orderly system of barbs projecting =

sideways from a central shaft. Thus, the quill pen was born. Lined up =

and layered across one another on the arms, these more complex feathers =

then joined into wings. Some of the Liaoning dinosaurs, such as the =

raven-sized Microraptor described by Xu Xing of Beijing's Institute of =

Vertebrate Paleontology and Paleoanthropology, also had wings on the =

legs and tail, an arrangement unknown in any modern bird.

Why did these dinosaurs convert their fuzz into wings? The intuitive =

answer is flight: the maniraptorans were turning their bodies into =

airplanes, and the wings evolved to become the airfoils that generate =

lift. But a closer look at the fossil evidence suggests otherwise. =

Although some of the small winged critters such as Microraptor could =

probably glide, as has been demonstrated by wind-tunnel experiments and =

computer simulations led by Gareth Dyke of the University of Debrecen in =

Hungary, others such as Zhenyuanlong from Jinzhou had hefty, short-armed =

bodies that were confined to the ground. Moreover, none of these winged =

dinosaurs had the huge chest muscles necessary to power flight, and few =

had the asymmetrical quill pens (with a shorter and stiffer leading vane =

compared with the trailing vane) that are optimized to withstand the =

severe forces of surging through an airstream.

The latest findings suggest that wings instead evolved to serve another, =

less widely recognized function: display. One line of evidence comes =

from work pioneered by Jakob Vinther of the University of Bristol in =

England, who uses high-powered microscopes to identify the =

pigment-bearing structures, called mela-nosomes, in fossil dinosaur =

feathers. It turns out that the feathers of nonflying, winged dinosaurs =

were a rainbow of colors. Some were even iridescent, like the plumage of =

today's crows. These shiny-sheened accoutrements would have been perfect =

for attracting mates or intimidating rivals.

The apparent splendor of these dinosaur feathers has spawned a radical =

new hypothesis for the origin of wings: they first evolved as =

advertisements=E2=80=94billboards projecting from the arms and legs and tai=
l. =

Then these suave-winged dinosaurs suddenly found themselves with big, =

broad surfaces that also, by the laws of physics, had an aerodynamic =

function. In other words, flight evolved by accident. And it may have =

evolved many times in parallel, as different maniraptorans found =

themselves generating lift from their wings as they leaped from the =

ground, scurried up trees or jumped between branches. Ultimately members =

of one of these maniraptoran lineages got small, developed big chest =

muscles and hyperelongated arms, and lost their long tails, becoming the =

birds of today.
PIECEMEAL EVOLUTION

the evolution of feathers and wings is emblematic of a much bigger =

pattern. The Liaoning dinosaurs demonstrate that many other supposedly =

singular features of birds first evolved millions of years before birds =

themselves and for reasons totally unrelated to flight.

Long, straight legs and feet with three skinny main toes=E2=80=94hallmarks =
of =

the modern bird silhouette=E2=80=94first appeared more than 230 million yea=
rs =

ago in the most primitive dinosaurs. Their emergence seems to be part of =

an overall reshaping of dinosaur bodies into upright-walking, =

fast-running machines that could outpace and outhunt their rivals. These =

hind-limb features are some of the defining characteristics of all =

dinosaurs, the very things that helped them rule the world for so long. =

Some of these dinosaurs=E2=80=94the earliest members of the theropod =

dynasty=E2=80=94then fused their left and right collarbones into a new =

structure, the wishbone. It was a seemingly minor change, which =

stabilized the shoulder girdle and allowed these stealthy, dog-sized =

predators to better absorb the shock forces of grabbing prey. Birds =

later co-opted the wishbone to serve as a spring that stores energy when =

they flap their wings.

The distinctive hollow bones and rapid growth of birds, both of which =

are important for flight, also have deep dinosaurian roots. Many =

dinosaurs had bones hollowed out by air sacs, a telltale sign that they =

had ultraefficient =E2=80=9Cflow-through=E2=80=9D lungs that take in oxygen=
during not =

only inhalation but also exhalation. In birds, this type of lung =

delivers the juice needed to maintain their high-energy way of life, in =

addition to lightening the skeleton for flight. The microscopic =

structure of dinosaur bones, meanwhile, indicates that these animals had =

growth rates and physiologies intermediate between slow-maturing, =

cold-blooded reptiles and the fast-growing, warm-blooded birds of today. =

Thus, researchers now know that a flow-through lung and fast growth =

emerged more than 100 million years before birds took wing, when the =

first fast-running, long-legged dinosaurs were carving out a new =

livelihood as energetic dynamos=E2=80=94so different from the sluggish =

amphibians, lizards and crocodiles they were battling against.

The pint-sized proportions of birds=E2=80=94infinitely daintier than T. rex=
and =

company=E2=80=94also stem from a time before birds themselves. Mike Lee of =

Flinders University in Australia and Roger Benson of the University of =

Oxford have independently determined that small body size evolved =

through a gradual trend of reduction that began with maniraptorans and =

lasted more than 50 million years. Exactly what drove this trend is =

unclear, but one possibility is that the ever shrinking physiques of =

these feathery dinosaurs gave them entry to new ecological niches=E2=80=94t=
rees, =

brush, perhaps even underground caves or burrows that were inaccessible =

to giants such as Brachiosaurus and Stegosaurus.

Neurological and behavioral attributes of living birds can be traced =

back to the dinosaurs, too. Much of the key evidence for the deep =

history of these traits comes from the Gobi Desert in Mongolia, where =

for the past quarter of a century a joint team from the American Museum =

of Natural History (AMNH) in New York City and the Mongolian Academy of =

Sciences has been collecting fossils. Under the leadership of Mark =

Norell and Mike Novacek of the AMNH, the annual summer expeditions have =

compiled a bounty of specimens from the Late Cretaceous period, between =

84 million and 66 million years ago, that provide unprecedentedly =

detailed insights into the lives of dinosaurs and early birds. Among =

their finds is a trove of well-preserved skulls belonging to =

Velociraptor and other feathered maniraptorans. CT scanning of these =

specimens, conducted by Amy Balanoff of Stony Brook University, has =

revealed that these species had a big brain and that the forward-most =

part of the organ was expanded. A large forebrain is what makes birds so =

intelligent and acts as their in-flight computer, allowing them to =

control the complicated business of flying and to navigate the complex =

3-D world of the air. Scientists do not yet know why these dinosaurs =

evolved such keen intelligence, but the fossils clearly show that the =

ancestors of birds got smart before they took to the skies.

The bird body plan was therefore not so much a fixed blueprint but more =

of a Lego set that was assembled brick by brick over evolutionary time. =

The transition between dinosaur and bird did not happen in one fell =

swoop but through tens of millions of years of gradual evolution.
A SEAMLESS TRANSITION

the transition from dinosaur to bird was so gradual, in fact, that there =

is no clear distinction between =E2=80=9Cnonbirds=E2=80=9D and =E2=80=9Cbir=
ds=E2=80=9D on the family =

tree, as I demonstrated in 2014 using statistics. My study stemmed from =

my Ph.D. project, under Norell's tutelage. In addition to his 25-year =

quest in the Gobi, Norell has been working with successive waves of =

graduate students over the past two decades to build ever larger family =

trees of dinosaurs. He and I, along with our colleagues Graeme Lloyd of =

the University of Leeds in England and Steve Wang of Swarthmore College, =

compiled a data set of more than 850 skeletal features of some 150 =

theropods spanning the dinosaur-to-bird transition. We then used =

multivariate statistics to plot each species in a so-called =

morphospace=E2=80=94basically a map that clusters species together based on=
the =

percentage of features they share. Two species that are very similar =

anatomically plot close together, like Chicago and Indianapolis on a =

road map, whereas two species with vastly different skeletons sit far =

apart, like Chicago and Phoenix. If birds evolved from dinosaurs via a =

series of rapid, dramatic mutations that quickly produced a totally =

different type of animal, then the two groups should plot onto =

distinctly different parts of the map. Instead the morphospace we =

produced was a mess: birds were interspersed among a bigger cloud of =

dinosaurs. There was no clear separation between them, indicating that =

the transition was so slow as to be imperceptible.

Birds, therefore, are just another type of dinosaur. If I had been =

standing around in Jinzhou some 125 million years ago, when Zhenyuanlong =

was alive and flapping its wings in vain as it tried to outrun the ash =

cloud that would eventually suffocate it, I probably would have simply =

regarded it as some kind of large bird. I would have considered =

dinosaurs and birds to be the same general thing. That it is technically =

categorized as a dinosaur and not a bird has to do with scientific =

convention and tradition: paleontologists have long defined birds as =

anything that stems from the most recent common ancestor of Huxley's =

Archaeopteryx and modern birds=E2=80=94basically small animals with full-on =

wings that could fly. Because dromaeosaurids such as Zhenyuanlong are a =

few branches outside of that part of the family tree, they are not =

considered to be birds by definition.

Yet we should not sell birds short. They may be dinosaurs, not a class =

apart on their own, but they are special. They carved out a completely =

new way of life, and today they thrive as upward of 10,000 species that =

exhibit a spectacular diversity of forms, from hummingbirds to =

ostriches. What is more, birds were able to hold on while all the other =

dinosaurs died out 66 million years ago.

It is remarkable to think of all the random twists of fate that worked =

over tens of millions of years to produce this indomitable group of =

animals. Their ancestors did not know they were becoming more birdlike. =

Nor could any of us, if we were around as witnesses, have predicted that =

many of the features that developed to help these dinosaurs keep warm or =

attract mates would eventually be repurposed as integral components of a =

flight system.

Evolution has no foresight; it acts only on what is available in the =

moment, shaped by the never-ending but always changing pressures of =

environment and competition. There was no moment when a dinosaur became =

a bird, no big bang when a T. rex turned into a chicken. It was a =

journey. And the more scientists learn about other major evolutionary =

transitions=E2=80=94fish evolving into tetrapods with limbs and digits, lan=
d =

mammals turning into whales, tree-swinging primates becoming =

upright-walking humans=E2=80=94the more we see a consistent theme in how th=
is =

kind of transformation works: it is a marathon, not a sprint, and there =

is no finish line.

One more facet of the bird-origins saga bears mention here. The =

statistical study my colleagues and I carried out may explain how birds =

persevered through the cataclysmic extinction event that claimed the =

other dinosaurs. As part of that work, we used our big data set to =

measure evolutionary rates: how quickly birds and their dinosaur cousins =

were changing features of their skeleton, which is a sign of =

evolutionary vitality. And the results surprised us. Those =

earliest-emerging birds that lived alongside their dinosaur forebears =

were evolving at supercharged rates=E2=80=94faster than Velociraptor, =

Zhenyuanlong and other nonbird species. It seems that once a small, =

flight-capable dinosaur had been assembled, once that Lego kit was =

complete, incredible evolutionary potential was unlocked. These airborne =

dinosaurs now had access to new ecological niches and opportunities. And =

whereas their brethren were unable to cope with the apocalyptic impact =

of the six-mile-wide asteroid that slammed into Earth at the end of the =

Cretaceous, birds flew right through the destruction=E2=80=94and had a new =
world =

to conquer on the other side.
MORE TO EXPLORE

Gradual Assembly of Avian Body Plan Culminated in Rapid Rates of =

Evolution across the Dinosaur-Bird Transition. Stephen L. Brusatte et =

al. in Current Biology, Vol. 24, No. 20, pages 2386=E2=80=932392; October 2=
0, 2014.

A Large, Short-Armed, Winged Dromaeosaurid (Dinosauria: Theropoda) from =

the Early Cretaceous of China and Its Implications for Feather =

Evolution. Junchang L=C3=BC and Stephen L. Brusatte in Scientific Reports, =

Vol. 5, Article No. 11775; July 16, 2015.
FROM OUR ARCHIVES

The Origin of Birds and Their Flight. Kevin Padian and Luis M. Chiappe; =

February 1998.

~~~~~~~~

Stephen Brusatte is a paleontologist at the University of Edinburgh in =

Scotland. He studies how major groups of animals, including dinosaurs =

and birds, evolve over long timescales.
IN BRIEF

Scientists have known for some time now that birds evolved from =

dinosaurs and are in fact a subgroup of dinosaurs. A rich fossil record =

of feathered dinosaurs discovered in China and elsewhere documents in =

detail the dramatic transformation of behemoth terrestrial dinosaurs =

into small, flight-capable birds.

New techniques for analyzing fossils have enabled researchers to =

reconstruct how the distinctive bird body plan came together. The =

results indicate that the group's hallmark traits emerged piecemeal over =

tens of millions of years, for purposes other than those they serve today.

The findings add to a growing body of evidence suggesting that major =

evolutionary transitions proceed gradually, not rapidly.
FINDINGS

A Gradual Transformation

Scientists have long wondered how evolution produces entirely new groups =

of organisms. The fossil record of birds and their dinosaur ancestors =

indicates that such transitions unfold very slowly. The hallmark traits =

of birds accumulated piecemeal over tens of millions of years and in =

many cases originated for reasons unrelated to the purposes they now serve.
Distinctive Anatomy

Birds have a multitude of characteristics that set them apart from other =

modern creatures. Many of these features function to enable flight.

PHOTO (COLOR): FEATHERED DINOSAUR Zhenyuanlong from Jinzhou, China, is =

one of many recently discovered fossils that document how birds arose =

from their terrestrial ancestors to conquer the skies.

PHOTO (COLOR)

PHOTO (COLOR)

PHOTO (COLOR)
Scientific American is a registered trademark of Nature America, Inc. =

and its content may not be copied or emailed to multiple sites or posted =

to a listserv without the copyright holder's express written permission. =

However, users may print, download, or email articles for individual use.
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  1. 2016-12-01 Ruben Safir <ruben.safir-at-my.liu.edu> Subject: [Learn] Fwd: Patrolling the Dark Net,
  2. 2016-12-02 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Tutorial on threaded binary tree part 1: simple
  3. 2016-12-03 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Witner Labs
  4. 2016-12-04 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Nice lecture on Quantum Mechanics
  5. 2016-12-05 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] information access, copyright wars and DRM
  6. 2016-12-06 Christopher League <league-at-contrapunctus.net> Re: [Learn] png data format
  7. 2016-12-06 Christopher League <league-at-contrapunctus.net> Re: [Learn] png data format
  8. 2016-12-06 Christopher League <league-at-contrapunctus.net> Re: [Learn] png data format
  9. 2016-12-06 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] png data format
  10. 2016-12-06 Christopher League <league-at-contrapunctus.net> Re: [Learn] png data format
  11. 2016-12-06 Ruben Safir <ruben.safir-at-my.liu.edu> Re: [Learn] png data format
  12. 2016-12-06 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] png data format
  13. 2016-12-06 Christopher League <league-at-contrapunctus.net> Re: [Learn] png data format
  14. 2016-12-06 Ruben Safir <mrbrklyn-at-panix.com> Re: [Learn] png data format
  15. 2016-12-06 Christopher League <league-at-contrapunctus.net> Re: [Learn] png data format
  16. 2016-12-06 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] [Hangout-NYLXS] png data format
  17. 2016-12-06 John Bowler <john.cunningham.bowler-at-gmail.com> Re: [Learn] [png-mng-implement] 4 byte length storage
  18. 2016-12-06 John Bowler <john.cunningham.bowler-at-gmail.com> Re: [Learn] [png-mng-implement] 4 byte length storage
  19. 2016-12-06 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] [png-mng-implement] 4 byte length storage
  20. 2016-12-06 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Ocaml
  21. 2016-12-06 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Re: [luny-talk] Humble Bundle O'Reilly UNIX books
  22. 2016-12-06 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] JT's words
  23. 2016-12-06 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] png data format
  24. 2016-12-07 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Re: png data format
  25. 2016-12-08 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: png data format
  26. 2016-12-08 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Re: png data format
  27. 2016-12-08 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Re: png data format
  28. 2016-12-10 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] references to pointers
  29. 2016-12-10 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] C++ returning lvalue references and pointers and refs
  30. 2016-12-10 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] const puzzle and literal type arguments
  31. 2016-12-11 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Re: png data format
  32. 2016-12-12 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] Fwd: Re: png data format
  33. 2016-12-12 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] gene phylogienics of homonids
  34. 2016-12-13 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Bit Depth
  35. 2016-12-13 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] C++ Threads Workshop
  36. 2016-12-13 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Summer Jobs
  37. 2016-12-14 From: "Mancini, Sabin (DFS)" <Sabin.Mancini-at-dfs.ny.gov> Subject: [Learn] For Ruben ( + those in NYC Metro ) : Holiday Social Event
  38. 2016-12-14 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Re: [dinosaur] Ceratopsid (Centrosaurinae:
  39. 2016-12-15 Ruben Safir <ruben.safir-at-my.liu.edu> Re: [Learn] Happy Holidays
  40. 2016-12-15 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] zlib demo with vector::resize
  41. 2016-12-15 John Bowler <john.cunningham.bowler-at-gmail.com> Re: [Learn] [png-mng-implement] 4 byte length storage
  42. 2016-12-15 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: [dinosaur] Elephant bird nuclear genome fragments
  43. 2016-12-15 Christopher League <league-at-contrapunctus.net> Subject: [Learn] zlib demo with vector::resize
  44. 2016-12-16 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] zlib demo with vector::resize
  45. 2016-12-16 Christopher League <league-at-contrapunctus.net> Re: [Learn] zlib demo with vector::resize
  46. 2016-12-16 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] PNG Parallel Programming problem
  47. 2016-12-17 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] [Hangout-NYLXS] I'm sure it's a coincidence, part n+1
  48. 2016-12-17 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] irc thread on the use of object methods in threads
  49. 2016-12-17 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] PNG threaded program
  50. 2016-12-18 ruben safir <ruben-at-mrbrklyn.com> Re: [Learn] Threads and Object Methods
  51. 2016-12-18 ruben safir <ruben-at-mrbrklyn.com> Re: [Learn] Threads and Object Methods
  52. 2016-12-18 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Look C++ is a functional programming language
  53. 2016-12-19 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] C++ Threading
  54. 2016-12-19 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] C++ Threading
  55. 2016-12-19 ISOC-NY announcements <announce-at-lists.isoc-ny.org> Subject: [Learn] [isoc-ny] JOB: Telecommunications Policy Specialist -at- NTIA
  56. 2016-12-20 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] F'ing Mouse Pad
  57. 2016-12-20 mrbrklyn <mrbrklyn-at-panix.com> Subject: [Learn] Phylogenetic study worth noting
  58. 2016-12-21 Samir Iabbassen <Samir.Iabbassen-at-liu.edu> Re: [Learn] Noobdy is home
  59. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Re: [Learn] Noobdy is home
  60. 2016-12-21 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] Noobdy is home
  61. 2016-12-21 Samir Iabbassen <Samir.Iabbassen-at-liu.edu> Re: [Learn] thread concurancy
  62. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Re: [Learn] thread concurancy
  63. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: lamda's in classes
  64. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: lamda's in classes
  65. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: thread concurancy
  66. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  67. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  68. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  69. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  70. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  71. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  72. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  73. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  74. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Re: Threads and Object Methods
  75. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) thread concurancy
  76. 2016-12-21 Ruben Safir <mrbrklyn-at-panix.com> Subject: [Learn] (fwd) Threads and Object Methods
  77. 2016-12-21 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] I need help
  78. 2016-12-21 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Noobdy is home
  79. 2016-12-21 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] thread concurancy
  80. 2016-12-21 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] [Hangout-NYLXS] Marnchester by the Sea
  81. 2016-12-22 Ruben Safir <mrbrklyn-at-panix.com> Re: [Learn] [Hangout-NYLXS] And be aware you were an unexcused
  82. 2016-12-22 ruben safir <ruben-at-mrbrklyn.com> Subject: [Learn] Fwd: Re: thread concurancy
  83. 2016-12-23 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] HOPL (History of Programming Languages)
  84. 2016-12-23 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] Noobdy is home
  85. 2016-12-23 Ruben Safir <ruben-at-mrbrklyn.com> Re: [Learn] Tiny Compiler in many languages at Rosettacode.org
  86. 2016-12-25 Ruben Safir <ruben-at-mrbrklyn.com> Subject: [Learn] Google and C++
  87. 2016-12-25 Ruben Safir <ruben.safir-at-my.liu.edu> Subject: [Learn] phylogentics
  88. 2016-12-27 Samir Iabbassen <Samir.Iabbassen-at-liu.edu> Re: [Learn] thread concurancy

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