The interplay between a changing Earth and its evolving organisms is the underlying theme of the book. The book has a dedicated website which explores additional enriching information and discussion, and provides or points to the art for the book and many other images useful for teaching. See: www. Charlie Mackesy offers inspiration and hope in uncertain times in this beautiful book based on his famous quartet of characters.
The Boy, the Mole, the Fox, and the Horse explores their unlikely friendship and the poignant, universal lessons they learn together. A modern classic in the vein of The Tao of Pooh, The Alchemist, and The Giving Tree, this charmingly designed keepsake will be treasured for generations to come. How did flying birds evolve from running dinosaurs, terrestrial trotting tetrapods evolve from swimming fish, and whales return to swim in the sea?
These are some of the great transformations in the million-year history of vertebrate life. And with the aid of new techniques and approaches across a range of fields—work spanning multiple levels of biological organization from DNA sequences to organs and the physiology and ecology of whole organisms—we are now beginning to unravel the confounding evolutionary mysteries contained in the structure, genes, and fossil record of every living species.
This book gathers a diverse team of renowned scientists to capture the excitement of these new discoveries in a collection that is both accessible to students and an important contribution to the future of its field. Marshaling a range of disciplines—from paleobiology to phylogenetics, developmental biology, ecology, and evolutionary biology—the contributors attack particular transformations in the head and neck, trunk, appendages such as fins and limbs, and the whole body, as well as offer synthetic perspectives.
Illustrated throughout, Great Transformations in Vertebrate Evolution not only reveals the true origins of whales with legs, fish with elbows, wrists, and necks, and feathered dinosaurs, but also the relevance to our lives today of these extraordinary narratives of change. A comprehensive reference to the life and lore of the sea examines the diverse creatures that make the seas their home, the mysteries of marine geography, and the stories of seafarers and the development of the tools of navigation.
I didn't want this story to end! So in late , when handsome Chase Andrews is found dead, the locals immediately suspect Kya Clark, the so-called Marsh Girl. But Kya is not what they say. Sensitive and intelligent, she has survived for years alone in the marsh that she calls home, finding friends in the gulls and lessons in the sand. Then the time comes when she yearns to be touched and loved. When two young men from town become intrigued by her wild beauty, Kya opens herself to a new life--until the unthinkable happens.
Where the Crawdads Sing is at once an exquisite ode to the natural world, a heartbreaking coming-of-age story, and a surprising tale of possible murder. Owens reminds us that we are forever shaped by the children we once were, and that we are all subject to the beautiful and violent secrets that nature keeps.
Skip to content. Your Inner Fish. Your Inner Fish Book Review:. Some Assembly Required. Some Assembly Required Book Review:. Creationists will want this book banned because it presents irrefutable evidence for a transitional creature that set the stage for the journey from sea to land. This engaging book combines the excitement of discovery with the rigors of great scholarship to provide a convincing case of evolution from fish to man.
With clarity and wit, Shubin shows us how exciting it is to be in the new age of discovery in evolutionary biology. He gives us personal anecdotes as well. He describes his career, from how he first learned to find fossils, to his teams accidental uncovering o. From the author of national bestseller, Your Inner Fish, this extraordinary journey of discovery spans centuries, as explorers and scientists seek to understand the origins of life's immense diversity.
For more than a century, paleontologists have traveled the globe to find fossils that show how such changes have happened. We have now arrived at a remarkable moment—prehistoric fossils coupled with new DNA technology have given us the tools to answer some of the basic questions of our existence: How do big changes in evolution happen?
Is our presence on Earth the product of mere chance? This new science reveals a multibillion-year evolutionary history filled with twists and turns, trial and error, accident and invention. In Some Assembly Required, Neil Shubin takes readers on a journey of discovery spanning centuries, as explorers and scientists seek to understand the origins of life's immense diversity.
In Your Inner Fish, Neil Shubin delved into the amazing connections between human bodies—our hands, heads, and jaws—and the structures in fish and worms that lived hundreds of millions of years ago. In The Universe Within, with his trademark clarity and exuberance, Shubin takes an even more expansive approach to the question of why we look the way we do.
As he moves from our very molecular composition a result of stellar events at the origin of our solar system through the workings of our eyes, Shubin makes clear how the evolution of the cosmos has profoundly marked our own bodies. This page guide for "Your Inner Fish" by Neil Shubin includes detailed chapter summaries and analysis covering 11 chapters, as well as several more in-depth sections of expert-written literary analysis.
Featured content includes commentary on major characters, 25 important quotes, essay topics, and key themes like Interrelatedness of All Living Creatures and Repurposing Organs for New Functions. Neil Shubin draws on the latest genetic research and his huge experience as an expeditionary paleontologist to show the incredible impact the 3.
He takes readers on a fascinating, unexpected journey and allows us to discover the deep connection to nature in our own bodies. On his faculty page on the University of Chicago website, Neil Shubin writes: The philosophy that underlies all of my empirical work is derived from the conviction that progress in the study of evolutionary biology results from linking research across diverse temporal, phylogenetic, and structural scales. Writing in a friendly, accessible way, Shubin explains the various historical records that are encoded in the human body, from the structures of our eyes to the sequencing of our genes.
A graduate of the Evergreen State School in Olympia, WA, Nicole has since written about such varied topics as modern urban farming, the role of glitterbombing as political theater, and the economic impacts of natural disasters. He tells us about his expeditions to the far north in Canada, to Ellesmere Island, where he and his team of paleontologists and fossil finders scoured the rocks to try and find a transitional fossil from the time that the first animals were venturing onto land.
The discovery of Tiktaalik Roseae is inarguably a transitional species, an intermediate between fish and the first land-walking tetrapods.
In this and in other species, scientists have been able to trace the twisting path of our own anatomys evolution. In Tiktaalik, we are able to see the beginning of our limbs, from the muscles in our shoulders and chest to the bones of our wrists. Shubin traces our connections to animals past and present. Each chapter is devoted to a different part of the body: our hands, facial nerves, teeth inner ear, eyes, brain, olfactory sense.
He gives us personal anecdotes as well. He describes his career, from how he first learned to find fossils, to his teams accidental uncovering of a tritheledont fossil, to the long search that led to finding Tiktaalik. Author : Publisher: ISBN: OCLC Category: Page: View: Read Now » Neil Shubin, a leading paleontologist and professor of anatomy who discovered Tiktaalik--the "missing link" that made headlines around the world in April tells the story of evolution by tracing the organs of the human body back millions of years, long before the first creatures walked the earth.
By examining fossils and DNA, Shubin shows us that our hands actually resemble fish fins, our head is organized like that of a long-extinct jawless fish, and major parts of our genome look and function like those of worms and bacteria.
From the author of national bestseller, Your Inner Fish, this extraordinary journey of discovery spans centuries, as explorers and scientists seek to understand the origins of life's immense diversity. For more than a century, paleontologists have traveled the globe to find fossils that show how such changes have happened.
We have now arrived at a remarkable moment—prehistoric fossils coupled with new DNA technology have given us the tools to answer some of the basic questions of our existence: How do big changes in evolution happen?
Is our presence on Earth the product of mere chance? This new science reveals a multibillion-year evolutionary history filled with twists and turns, trial and error, accident and invention. In Your Inner Fish, Neil Shubin delved into the amazing connections between human bodies—our hands, heads, and jaws—and the structures in fish and worms that lived hundreds of millions of years ago.
As he moves from our very molecular composition a result of stellar events at the origin of our solar system through the workings of our eyes, Shubin makes clear how the evolution of the cosmos has profoundly marked our own bodies. Featured content includes commentary on major characters, 25 important quotes, essay topics, and key themes like Interrelatedness of All Living Creatures and Repurposing Organs for New Functions.
It reflects recent theoretical and methodological developments in this field which seek to understand the ways that ideas and matter, minds and bodies exist together within an immanent frame of reference.
Virtually all of the features that this creature shares with landliving creatures look very primitive. The same is true of the shape of the skull and the shoulder. The answer came from million-year-old rocks, formed in ancient streams. I sent them a picture of the fossil, and the elders came up with two suggestions, Siksagiaq and Tiktaalik. This attention ushered in a week unlike any other in my normally quiet life.
Though for me the greatest moment of the whole media blitz was not seeing the political cartoons or reading the editorial coverage and the heated discussions on the blogs. Then I asked what they thought it was.
Hands shot up. Big teeth, too. Other children started to voice their dissent. For our purposes, there is an even more profound take on Tiktaalik. How can I be so sure that this fossil says something about my own body?
Consider the neck of Tiktaalik. Tiktaalik is different. The head is completely free of the shoulder. This whole arrangement is shared with amphibians, reptiles, birds, and mammals, including us.
So what have we learned? Our world is so highly ordered that we can use a walk through a zoo to predict the kinds of fossils that lie in the different layers of rocks around the world. Those predictions can bring about fossil discoveries that tell us about ancient events in the history of life.
The record of those events remains inside us, as part of our anatomical organization. Imagine walking into a room where you will spend several months taking a human body apart layer by layer, organ by organ, all as a way to learn tens of thousands of new names and body structures. It turned out that my imagined world in no way prepared me for the experience. We were to dissect the chest, so we exposed it while leaving the head, arms, and legs wrapped in preservative-drenched gauze.
The tissues did not look very human. I began to think that the cadaver looked more like a doll than a human. A few weeks went by as we exposed the organs of the chest and abdomen. I did my initial dissections, made my cuts, and learned the anatomy of most of the major organs. This was no doll or mannequin; this had once been a living person, who used that hand to carry and caress.
Suddenly, this mechanical exercise, dissection, became deeply and emotionally personal. Until that moment, I was blind to my connection to the cadaver. I had already exposed the stomach, the gallbladder, and other organs; but what sane person forms a human connection at the sight of a gallbladder?
What is it about a hand that seems quintessentially human? The answer must, at some level, be that the hand is a visible connection between us; it is a signature for who we are and what we can attain. Our ability to grasp, to build, and to make our thoughts real lies inside this complex of bones, nerves, and vessels.
The immediate thing that strikes you when you see the inside of the hand is its compactness. The ball of your thumb, the thenar eminence, contains four different muscles. Twiddle your thumb and tilt your hand: ten different muscles and at least six different bones work in unison. Inside the wrist are at least eight small bones that move against one another.
Bend your wrist, and you are using a number of muscles that begin in your forearm, extending into tendons as they travel down your arm to end at your hand. Even the simplest motion involves a complex interplay among many parts packed in a small space.
The relationship between complexity and humanity within our hands has long fascinated scientists. In , the eminent Scottish surgeon Sir Charles Bell wrote the classic book on the anatomy of hands. In his eye, this designed perfection could only have a divine origin. He was fortunate to be an anatomist in the mids, when there were still entirely new kinds of animals to discover living in the distant reaches of the earth. As more and more parts of the world were explored by westerners, all sorts of exotic creatures made their way back to laboratories and museums.
In comparing this pattern with the diversity of skeletons in the world, Owen made a remarkable discovery. What he found, and later promoted in a series of lectures and volumes, were exceptional similarities among creatures as different as frogs and people. This pattern underlies the architecture of all limbs. Want to make a bat wing? Make a horse? How about a frog leg?
Elongate the bones of the leg and fuse several of them together. Despite radical changes in what limbs do and what they look like, this underlying blueprint is always present. There is a fundamental design in the skeleton of all animals. Frogs, bats, humans, and lizards are all just variations on a theme.
That theme, to Owen, was the plan of the Creator. Shortly after Owen announced this observation in his classic monograph On the Nature of Limbs, Charles Darwin supplied an elegant explanation for it.
The reason the wing of a bat and the arm of a human share a common skeletal pattern is because they shared a common ancestor. The same reasoning applies to human arms and bird wings, human legs and frog legs—everything that has limbs. Where, then, do we look for the history of the limb pattern? Our limbs have nothing like this, nor do the limbs of any other creature alive today. All limbs have a single long bone at their base: the humerus in the upper arm and the femur in the upper leg.
African explorers brought one to Owen. Locals found them delicious. To anatomists, the comparison was obvious. Our upper arm has a single bone, and that single bone, the humerus, attaches to our shoulder. As a handful of these living species became known in the s, clues started to come from another source.
In the s, the rocks provided more surprises. A young Swedish paleontologist, Gunnar Save-Soderbergh, was given the extraordinary opportunity to explore the east coast of Greenland for fossils. The region was terra incognita, but Save-Soderbergh recognized that it featured enormous deposits of Devonian rocks. Newspapers around the world trumpeted his discovery; editorials analyzed its importance; cartoons lampooned it. After Save-Soderbergh died, the fossils were described by his colleague Erik Jarvik, who named one of the new species Ichthyostega soderberghi in honor of his friend.
For our story, Ichthyostega is a bit of a letdown. Another creature, one that received little notice when Save-Soderbergh announced it, was to provide real insights decades later. This suggested to her that the earliest limbs arose to help animals swim, not walk.
Acanthostega had a limb, albeit a very primitive one. The search for the origins of hands and feet, wrists and ankles had to go still deeper in time.
This is where matters stood until We had found a lovely cut on Route 15 north of Williamsport, where PennDOT had created a giant cliff in sandstones about million years old. The agency had dynamited the cliff and left piles of boulders alongside the highway. This was perfect fossil-hunting ground for us, and we stopped to crawl over the boulders, many of them roughly the size of a small microwave oven. Closest to the body was one bone. This one bone attached to two bones.
Sadly, we found only this isolated specimen. Stipple diagram used with the permission of Scott Rawlins, Arcadia University. Photo by the author. The answer would come only from whole skeletons. During the expedition, we had collected three chunks of rock, each about the size of a piece of carry-on luggage, from the Devonian of Ellesmere Island.
Then the rocks were wrapped in plaster for the trip home. Opening these kinds of plaster coverings in the lab is much like encountering a time capsule. Even the smell of the tundra comes wafting out of these packages as we crack the plaster open. Fred in Philadelphia and Bob in Chicago were scratching on different boulders at the same general time. The next piece of evidence came from Philadelphia a week later.
And that bone attached to four more beyond. Over the next months, we were able to see much of the rest of the appendage. Solutions to these puzzles are found in the structure of the bones and joints themselves. Tiktaalik has a shoulder, elbow, and wrist composed of the same bones as an upper arm, forearm, and wrist in a human.
When we study the structure of these joints to assess how one bone moves against another, we see that Tiktaalik was specialized for a rather extraordinary function: it was capable of doing push-ups. As for chest muscles, Tiktaalik likely had them in abundance. It helps to consider the rest of the animal.
But why live in these environments at all? Some were up to sixteen feet long, almost twice the size of the largest Tiktaalik. The teeth are barbs the size of railroad spikes.
Would you want to swim in these ancient streams? The strategies to succeed in this setting were pretty obvious: get big, get armor, or get out of the water.
Bend your wrist back and forth. Open and close your hand. Earlier, these joints did not exist. What do we make of the one bone—two bones—lotsa blobs— digits plan that Owen attributed to a Creator? Then there are creatures like Tiktaalik, with one bone—two bones—lotsa blobs. Tiktaalik might be able to do a push-up, but it could never throw a baseball, play the piano, or walk on two legs.
Finally, the full complement of wrist and ankle bones found in a human hand or foot is seen in reptiles more than million years old. But what are the major changes that enable us to use our hands or walk on two legs? How do these shifts come about? We humans, like many other mammals, can rotate our thumb relative to our elbow. This simple function is very important for the use of our hands in everyday life.
Imagine trying to eat, write, or throw a ball without being able to rotate your hand relative to your elbow. We can do this because one forearm bone, the radius, rotates along a pivot point at the elbow joint.
The structure of the joint at the elbow is wonderfully designed for this function. At the end of our upper-arm bone, the humerus, lies a ball. This ball-and-socket joint allows the rotation of our hand, called pronation and supination. Where do we see the beginnings of this ability? In creatures like Tiktaalik. When Tiktaalik bent its elbow, the end of its radius would rotate, or pronate, relative to the elbow.
This feature is critical: think of trying to walk with your kneecap facing backward. We start development with little limbs oriented much like those in Eusthenopteron, with elbows and knees facing in the same direction. As we grow in the womb, our knees and elbows rotate to give us the state of affairs we see in humans today.
Our bipedal pattern of walking uses the movements of our hips, knees, ankles, and foot bones to propel us forward in an upright stance unlike the sprawled posture of creatures like Tiktaalik. One big difference is the position of our hips. This change in posture came about by changes to the hip joint, pelvis, and upper leg: our pelvis became bowl shaped, our hip socket became deep, our femur gained its distinctive neck, the feature that enables it to project under the body rather than to the side.
Do the facts of our ancient history mean that humans are not special or unique among living creatures? Of course not. From common parts came a very unique construction. We are not separate from the rest of the living world; we are part of it down to our bones and, as we will see shortly, even our genes.
Both times I was uncovering a deep connection between my humanity and another being. Inside the purse once lay an egg with yolk, which developed into an embryonic skate or ray.
Over the years, Randy has spent hundreds of hours experimenting with the embryos inside these egg cases, often working well past midnight. During the fateful summer of , Randy was taking these cases and injecting a molecular version of vitamin A into the eggs. After that he would let the eggs develop for several months until they hatched. Why sharks?
Why a form of vitamin A? To make sense of these experiments, we need to step back and look at what we hope they might explain. What we are really getting at in this chapter is the recipe, written in our DNA, that builds our bodies from a single egg.
When sperm fertilizes an egg, that fertilized egg does not contain a tiny hand, for instance. The hand is built from the information contained in that single cell. This takes us to a very profound problem. But there is a big limitation to working with fossils. We cannot do experiments on long-dead animals.
Experiments are great because we can actually manipulate something to see the results. For this reason, my laboratory is split directly in two: half is devoted to fossils, the other half to embryos and DNA.
Life in my lab can be schizophrenic. The locked cabinet that holds Tiktaalik specimens is adjacent to the freezer containing our precious DNA samples. We begin with an apparent puzzle. Our body is made up of hundreds of different kinds of cells. This cellular diversity gives our tissues and organs their distinct shapes and functions.
The cells that make our bones, nerves, guts, and so on look and behave entirely differently. Despite these differences, there is a deep similarity among every cell inside our bodies: all of them contain exactly the same DNA.
If DNA contains the information to build our bodies, tissues, and organs, how is it that cells as different as those found in muscle, nerve, and bone contain the same DNA? The answer lies in understanding what pieces of DNA the genes are actually turned on in every cell. A skin cell is different from a neuron because different genes are active in each cell. Therefore, to understand what makes a cell in the eye different from a cell in the bones of the hand, we need to know about the genetic switches that control the activity of genes in each cell and tissue.
At conception, we start as a single cell that contains all the DNA needed to build our body. The plan for that entire body unfolds via the instructions contained in this single microscopic cell. To go from this generalized egg cell to a complete human, with trillions of specialized cells organized in just the right way, whole batteries of genes need to be turned on and off at just the right stages of development. Like a concerto composed of individual notes played by many instruments, our bodies are a composition of individual genes turning on and off inside each cell during our development.
This information is a boon to those who work to understand bodies, because we can now compare the activity of different genes to assess what kinds of changes are involved in the origin of new organs. Take limbs, for example. This kind of comparison gives us some likely culprits—the genetic switches that may have changed during the origin of limbs. We can then study what these genes are doing in the embryo and how they might have changed.
We can even do experiments in which we manipulate the genes to see how bodies actually change in response to different conditions or stimuli. To see the genes that build our hands and feet, we need to take a page from a script for the TV show CSI: Crime Scene Investigation—start at the body and work our way in. We will begin by looking at the structure of our limbs, and zoom all the way down to the tissues, cells, and genes that make it.
Likewise, our hands are different from one side to the other. Our pinkies are shaped differently from our thumbs.
The Holy Grail of our developmental research is to understand what genes differentiate the various bones of our limb, and what controls development in these three dimensions. What DNA actually makes a pinky different from a thumb? If we can understand the genes that control such patterns, we will be privy to the recipe that builds us.
Limbs begin their development as tiny buds that extend from our embryonic bodies. The buds grow over two weeks, until the tip forms a little paddle. All of the key stages in the development of a wing skeleton happen inside the egg.
To study how this pattern emerges, we need to look at embryos and sometimes interfere with their development to assess what happens when things go wrong. Moreover, we need to look at mutants and at their internal structures and genes, often by making whole mutant populations through careful breeding. Obviously, we cannot study humans in these ways. They needed an organism in which the limbs were accessible for observation and experiment.
The embryo had to be relatively large, so that they could perform surgical procedures on it. Importantly, the embryo had to grow in a protected place, in a container that sheltered it from jostling and other environmental disturbances.
In the s and s a number of biologists, including Edgar Zwilling and John Saunders, did extraordinarily creative experiments on chicken eggs to understand how the pattern of the skeleton forms. This was an era of slice and dice. Embryos were cut up and various tissues moved about to see what effect this had on development. The approach involved very careful microsurgery, manipulating patches of tissue no more than a millimeter thick. They discovered that two little patches of tissue essentially control the development of the pattern of bones inside limbs.
A strip of tissue at the extreme end of the limb bud is essential for all limb development. Remove it, and development stops. Remove it early, and we are left with only an upper arm, or a piece of an arm.
Remove it slightly later, and we end up with an upper arm and a forearm. Remove it even later, and the arm is almost complete, except that the digits are short and deformed. Let the chick develop and form a wing. The result surprised nearly everybody. The wing developed normally except that it also had a full duplicate set of digits. For example, take a chicken embryo and dab a little vitamin A on its limb bud, or simply inject vitamin A into the egg, and let the embryo develop.
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