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Narratives of Human Evolution Narratives of Human Evolution

Narratives of Human Evolution Narratives of Human Evolution

In the notoriously controversial field of paleoanthropology Misia Landau has found a hidden level of agreement among theories of human evolution. According to Landau, these theories are versions of the universal hero tale in folklore and myth. The narratives all have similar structures, featuring a humble hero (in theories of evolution it is a nonhuman primate) who departs on a journey (leaves his native habitat), receives essential aid or equipment from a donor figure (through evolutionary principles such as natural selection or orthogenesis), goes through tests (imposed by competitors, harsh climate, or predators), and finally arrives at a higher (that is, more human) state.

Analyzing classic texts on evolution by Darwin, Keith, and Elliott Smith, as well as more recent authors by scholars such as Dart, Robinson, Tobias, and Johanson, Landau reveals not only their common narrative form but also how this form accommodates differences in meaning—widely varying sequences of events, heroes, and donors. Landau shows how interpretations of the fossil record differ according to what the anthropologist believes it the primary evolutionary agent. She concludes that scientists have much to gain from an awareness that they are tellers of stories. An understanding of narrative, she argues, can provide tools for creating new scientific theories as well as for analyzing old ones. Her book will be entertaining and enlightening for both general readers and scholars.

Paperback: 215 pages
Publisher: Yale University Press; Reprint edition (March 11, 1993)

Anthropology (13th Edition) Anthropology (13th Edition)

Anthropology (13th Edition) Anthropology (13th Edition)

Anthropology, provides its readers with a comprehensive and scientific introduction to the four fields of anthropology. It helps them understand humans in all their variety, and why such variety exists. This new thirteenth edition places an increased emphasis on immigration, migration and globalization. It also showcases how anthropological skill sets can be applied beyond academia.

About the Author

Carol R. Ember started at Antioch College as a chemistry major. She began taking social science courses because some were required, but she soon found herself intrigued. There were lots of questions without answers, and she became excited about the possibility of a research career in social science. She spent a year in graduate school at Cornell studying sociology before continuing on to Harvard, where she studied anthropology primarily with John and Beatrice Whiting. For her Ph.D. dissertation she worked among the Luo of Kenya. While there she noticed that many boys were assigned "girls' work," such as babysitting and household chores, because their mothers (who did most of the agriculture) did not have enough girls to help out. She decided to study the possible effects of task assignment on the social behavior of boys. Using systematic behavior observations, she compared girls, boys who did a great deal of girls' work, and boys who did little such work. She found that boys assigned girls' work were intermediate in many social behaviors, compared with the other boys and girls. Later, she did cross-cultural research on variation in marriage, family, descent groups, and war and peace, mainly in collaboration with Melvin Ember, whom she married in 1970. All of these cross-cultural studies tested theories on data for worldwide samples of societies. From 1970 to 1996, she taught at Hunter College of the City University of New York. She has also served as president of the Society of Cross-Cultural Research and was one of the directors of the Summer Institutes in Comparative Anthropological Research, which were funded by the National Science Foundation. She is now executive director at the Human Relations Area Files, Inc., a nonprofit research agency at Yale University.

After graduating from Columbia College, Melvin Ember went to Yale University for his Ph.D. His mentor at Yale was George Peter Murdock, an anthropologist who was instrumental in promoting cross-cultural research and building a full-text database on the cultures of the world to facilitate cross-cultural hypothesis testing. This database came to be known as the Human Relations Area Files (HRAF) because it was originally sponsored by the Institute of Human Relations at Yale. Growing in annual installments and now distributed in electronic format, the HRAF database currently covers more than 370 cultures, past and present, all over the world. He did fieldwork for his dissertation in American Samoa, where he conducted a comparison of three villages to study the effects of commercialization on political life. In addition, he did research on descent groups and how they changed with the increase of buying and selling. His cross-cultural studies focused originally on variation in marital residence and descent groups. He also conducted cross-cultural research on the relationship between economic and political development, the origin and extension of the incest taboo, the causes of polygamy, and how archaeological correlates of social customs can help draw inferences about the past. After four years of research at the National Institute of Mental Health, he taught at Antioch College and then Hunter College of the City University of New York. Heserved as president of the Society for Cross-Cultural Research and was president (since 1987) of the Human Relations Area Files, Inc., a nonprofit research agency at Yale University, until his passing.

Paperback: 656 pages
Publisher: Pearson; 13 edition (February 11, 2010)

Anthropology: What Does It Mean to Be Human? Anthropology: What Does It Mean to Be Human?

Anthropology: What Does It Mean to Be Human? Anthropology: What Does It Mean to Be Human?

A unique alternative to more traditional, encyclopedic introductory texts, Anthropology: What Does It Mean to Be Human?, Second Edition, takes a question-oriented approach that incorporates cutting-edge theory and new ways of looking at important contemporary issues such as power, human rights, and inequality. With a total of fifteen chapters, this engaging, full-color text is an ideal one-semester overview that delves deep into anthropology without overwhelming students.

New to this Edition:

  • New discussions of gender and archaeology, domestication, social organization, nutritional anthropology, and aboriginality, and significantly updated discussions of genetics and race and human origins
  • Discussions of economic and political relations now appear in separate chapters
  • "Anthropology in Everyday Life" boxes now appear throughout the book to continually show students the applicability of anthropology
  • New "In Their Own Words" commentaries throughout
  • New module on the components of language
  • In addition to the running glossary, a glossary now appears at the end of the text
  • "For Review" sections now appear at the end of each chapter.

About the Author

Robert H. Lavenda is Professor of Anthropology and Co-chair of the Department of Anthropology at St. Cloud State University. Emily A. Schultz is Professor of Anthropology at St. Cloud State University.

Paperback: 528 pages
Publisher: Oxford University Press; 2 edition (December 7, 2011)

The Urantia Book The Urantia Book
The Urantia Book The Urantia Book


Love is truly contagious and eternally creative. (p. 2018) “Devote your life to proving that love is the greatest thing in the world.” (p. 2047) “Love is the ancestor of all spiritual goodness, the essence of the true and the beautiful.” (p. 2047) The Father’s love can become real to mortal man only by passing through that man’s personality as he in turn bestows this love upon his fellows. (p. 1289) The secret of a better civilization is bound up in the Master’s teachings of the brotherhood of man, the good will of love and mutual trust. (p. 2065)


Prayer is not a technique of escape from conflict but rather a stimulus to growth in the very face of conflict. (p. 1002) The sincerity of any prayer is the assurance of its being heard. … (p. 1639) God answers man’s prayer by giving him an increased revelation of truth, an enhanced appreciation of beauty, and an augmented concept of goodness. (p. 1002) …Never forget that the sincere prayer of faith is a mighty force for the promotion of personal happiness, individual self-control, social harmony, moral progress, and spiritual attainment. (p. 999)


There is a great and glorious purpose in the march of the universes through space. All of your mortal struggling is not in vain. (p. 364) Mortals only learn wisdom by experiencing tribulation. (p. 556)


The angels of all orders are distinct personalities and are highly individualized. (p. 285) Angels....are fully cognizant of your moral struggles and spiritual difficulties. They love human beings, and only good can result from your efforts to understand and love them. (p. 419)

Our Divine Destiny

If you are a willing learner, if you want to attain spirit levels and reach divine heights, if you sincerely desire to reach the eternal goal, then the divine Spirit will gently and lovingly lead you along the pathway of sonship and spiritual progress. (p. 381) …They who know that God is enthroned in the human heart are destined to become like him—immortal. (p. 1449) God is not only the determiner of destiny; he is man’s eternal destination. (p. 67)


Almost everything of lasting value in civilization has its roots in the family. (p. 765) The family is man’s greatest purely human achievement. ... (p. 939)


…Faith will expand the mind, ennoble the soul, reinforce the personality, augment the happiness, deepen the spirit perception, and enhance the power to love and be loved. (p. 1766) “Now, mistake not, my Father will ever respond to the faintest flicker of faith.” (p. 1733)


The story of man’s ascent from seaweed to the lordship of earthly creation is indeed a romance of biologic struggle and mind survival. (p. 731) 2,500,000,000 years ago… Urantia was a well developed sphere about one tenth its present mass. … (p. 658) 1,000,000,000 years ago is the date of the actual beginning of Urantia [Earth] history. (p. 660) 450,000,000 years ago the transition from vegetable to animal life occurred. (p. 669) From the year A.D. 1934 back to the birth of the first two human beings is just 993,419 years. (p. 707) About five hundred thousand years ago…there were almost one-half billion primitive human beings on earth. … (p. 741) Adam and Eve arrived on Urantia, from the year A.D. 1934, 37,848 years ago. (p. 828)

From the Inside Flap

What’s Inside?

Parts I and II

God, the inhabited universes, life after death, angels and other beings, the war in heaven.

Part III

The history of the world, science and evolution, Adam and Eve, development of civilization, marriage and family, personal spiritual growth.

Part IV

The life and teachings of Jesus including the missing years. AND MUCH MORE…


God, …God is the source and destiny of all that is good and beautiful and true. (p. 1431) If you truly want to find God, that desire is in itself evidence that you have already found him. (p. 1440) When man goes in partnership with God, great things may, and do, happen. (p. 1467)

The Origin of Human Life, The universe is not an accident... (p. 53) The universe of universes is the work of God and the dwelling place of his diverse creatures. (p. 21) The evolutionary planets are the spheres of human origin…Urantia [Earth] is your starting point. … (p. 1225) In God, man lives, moves, and has his being. (p. 22)

The Purpose of Life, There is in the mind of God a plan which embraces every creature of all his vast domains, and this plan is an eternal purpose of boundless opportunity, unlimited progress, and endless life. (p. 365) This new gospel of the kingdom… presents a new and exalted goal of destiny, a supreme life purpose. (p. 1778)

Jesus, The religion of Jesus is the most dynamic influence ever to activate the human race. (p. 1091) What an awakening the world would experience if it could only see Jesus as he really lived on earth and know, firsthand, his life-giving teachings! (p. 2083)

Science, Science, guided by wisdom, may become man’s great social liberator. (p. 909) Mortal man is not an evolutionary accident. There is a precise system, a universal law, which determines the unfolding of the planetary life plan on the spheres of space. (p. 560)

Life after Death, God’s love is universal… He is “not willing that any should perish.” (p. 39) Your short sojourn on Urantia [Earth]…is only a single link, the very first in the long chain that is to stretch across universes and through the eternal ages. (p. 435) …Death is only the beginning of an endless career of adventure, an everlasting life of anticipation, an eternal voyage of discovery. (p. 159)

About the Author

The text of The Urantia Book was provided by one or more anonymous contributors working with a small staff which provided editorial and administrative support during the book's creation. The book bears no particular credentials (from a human viewpoint), relying instead on the power and beauty of the writing itself to persuade the reader of its authenticity.

Leather Bound: 2097 pages
Publisher: Urantia Foundation; Box Lea edition (August 25, 2015)

Anthropology by Robert Ranulph Marett Anthropology

Anthropology Anthropology by Robert Ranulph Marett

This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it.

This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.

Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. To ensure a quality reading experience, this work has been proofread and republished using a format that seamlessly blends the original graphical elements with text in an easy-to-read typeface.

We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.

Paperback: 158 pages
Publisher: Pinnacle Press (May 24, 2017)

Lone Survivors: How We Came to Be the Only Humans on Earth Lone Survivors: How We Came to Be the Only Humans on Earth

Lone Survivors: How We Came to Be the Only Humans on Earth Lone Survivors: How We Came to Be the Only Humans on Earth

A leading anthropology researcher on human evolution proposes a new and controversial theory of how our species came to be.

In this groundbreaking and engaging work of science, world-renowned paleoanthropologist Chris Stringer sets out a new theory of humanity's origin, challenging both the multiregionalists (who hold that modern humans developed from ancient ancestors in different parts of the world) and his own "out of Africa" theory, which maintains that humans emerged rapidly in one small part of Africa and then spread to replace all other humans within and outside the continent. Stringer's new theory, based on archeological and genetic evidence, holds that distinct humans coexisted and competed across the African continent-exchanging genes, tools, and behavioral strategies.

Stringer draws on analyses of old and new fossils from around the world, DNA studies of Neanderthals (using the full genome map) and other species, and recent archeological digs to unveil his new theory. He shows how the most sensational recent fossil findings fit with his model, and he questions previous concepts (including his own) of modernity and how it evolved.

Lone Survivors is the definitive account of who and what we were, and will change perceptions about our origins and about what it means to be human.

About the Author

CHRIS STRINGER is the author of The Complete World of Human Evolution, Homo britannicus, and more than two hundred books and papers on the subject of human evolution. One of the world's foremost paleoanthropologists, he is a researcher at the Natural History Museum in London and a Fellow of the Royal Society. He has three children and lives in Sussex and London.

Paperback: 336 pages
Publisher: St. Martin's Griffin; First edition (July 30, 2013)

Written in Stone: Evolution, the Fossil Record, and Our Place in Nature Written in Stone: Evolution, the Fossil Record, and Our Place in Nature

Written in Stone: Evolution, the Fossil Record, and Our Place in Nature Written in Stone: Evolution, the Fossil Record, and Our Place in Nature

From Publishers Weekly

Starred Review. Beginning with a recently discovered 47-million-year-old primate fossil, Switek effectively and eloquently demonstrates the exponential increase in fossils that have been found since Darwin first published On the Origin of Species. In delightful prose, he blends information about fossil evidence with the scientific debates about how that evidence might be best interpreted. Switek, who writes the Smithsonian's Dinosaur Tracking blog, focuses on evidence for the evolution of major lineages, from reptiles to birds and from fish to tetrapods. He also explains at length how whales, horses, and humans evolved, marshaling compelling fossil evidence and combining it with information from molecular biology; at every step, he makes clear what is still unknown. He underscores that life forms have not "progressed" through evolution to end with Homo sapiens as the highest life form; rather, evolution has produced "a wildly branching tree of life with no predetermined path or endpoint." He superbly shows that "f we can let go of our conceit," we will see the preciousness of life in all its forms. 90 b&w illus. (Nov.) (c) (c) Copyright PWxyz, LLC. All rights reserved.

From Booklist

In this thoroughly entertaining science history, Switek combines a deep knowledge of the fossil record with a Holmesian compulsion to investigate the myriad ways evolutionary discoveries have been made. Just one chapter encompasses an 1817 Amazon expedition, Richard Owen and London’s Natural History Museum, the musings of Darwin, an array of late nineteenth- and twentieth-century naturalists, some digs in Greenland, and paleontologist Jenny Clack’s 1980 research in old field notebooks and a trip to the Sedgewick Museum basement. All of this leads in a roundabout way to the 2006 discovery of Tiktaalik: a fish with a critical position in the record between fins and fingers. From there Switek moves on to “footprints and feathers” and a dozen other topics that all further his mission of exploring natural history and portraying the scientists who spent their lives asking questions and finding answers. It’s poetry, serendipity, and smart entertainment because Switek has found the sweet spot between academic treatise and pop culture, a literary locale that is a godsend to armchair explorers everywhere. --Colleen Mondor

Paperback: 320 pages
Publisher: Bellevue Literary Press (November 30, 2010)



Ardipithecus Ramidus
Potential Human Ancestor

October 2, 2009 8:10 AM,
Brian Switek


Ardipithecus ramidus full skeletal restoration by artist Jay Matternes
Two restorations of "Ardi", a 45% complete skeleton of Ardipithecus ramidus published in Science. Restorations (including the full skeletal restoration below) by artist Jay Matternes.
Two restorations of "Ardi"

The stories of "Ida" and "Ardi" could hardly be more different.

Ida was a lemur-like primate that lived 47 million years ago in an area that is now Messel, Germany. Ardi was much closer to us; she was one of the earliest hominins and lived 4.4 million years ago in what would become known as Ethiopia.

When the bones of Ida were discovered they were held in a private collection for years before being sold for an undisclosed sum to paleontologist Jorn Hurum. The first bones of Ardi were found in the field in 1992 by paleoanthropologist Gen Suwa. Enough fossils were found for an initial publication two years later, but the search continued for years afterward. That search has yielded over 100 bones from Ardi's kind, representing about 36 individuals. Ardi is the most complete individual, with about 45% of the skeleton intact.

From almost the time of her acquisition by Hurum, Ida was groomed to be a star. The media company Atlantic Productions began to work with Hurum and immediately started the production of a book, several documentaries, and a bombastic public unveiling of a discovery they said would "CHANGE EVERYTHING." The scientists describing Ida were forced to rush their study to meet the deadline set by the company The bones of Ardi and her kin, by contrast, were scrutinized with great detail over 15 years. So secret was the study of her bones that some frustrated paleoanthropologists called it the "Manhattan Project of anthropology."

Ida was introduced to the public as the "ancestor of us all", but the science behind this claim was flimsy. She was more closely related to lemurs than to us. Ardi, however, sits relatively close to the base of the human (i.e. hominin) family tree. Whether our species can trace its ancestral heritage back through hers will be something that will be debated in the months and years to come, but she is nevertheless one of our closest extinct relatives.

Ardipithecus ramidus by Csotonyi
Ardipithecus ramidus by Csotonyi

Ardi, of course, is short for Ardipithecus ramidus, one of the earliest hominins found to date. Her skeleton (see image below), as well as bits and pieces of other skeletons of the same species, were described this week in a special edition of the journal Science. While a close relative of Australopithecus afarensis (made famous by "Lucy"), Ardipithecus ramidus is about half a million years older than the earliest Australopithecus afarensis and is a bit closer to the last common ancestor between living chimpanzees and humans.* As such the remains of Ardi and her kind give us a closer look at how some of the earliest humans evolved.

*[I apologize if these technical names are cumbersome, but they are important. There are only a few hominin genera but many species, and when talking about Ardipithecus it is important to distinguish between the species given attention in this post, Ardipithecus ramidus, and its older sister species Ardipithecus kadabba.]

Ardipithecus Skeleton

Contrary to the tirades of creationists, paleontologists have identified many evolutionary transitions in the fossil record, and the early history of hominins presents us with some of the most compelling evidence for evolutionary change. The nearly 45% complete skeleton of Ardipithecus ramidus, along with numerous other skeleton fragments from the same species, will enhance our understanding of what our earliest human relatives were like. Depending on your expectations, the skeleton is either very surprising or is consistent with ideas that have been kicked around for some time now.

One of the BIG questions in paleoanthropology, the kind that grabs the attention of the public as well as researchers, is "What was the last common ancestor of chimpanzees and humans like?" The traditional view is that the last common ancestor was a chimpanzee-like knuckle-walker, thus meaning that living chimpanzees are evolutionarily conservative (or have not changed much) while humans have changed radically. A key feature that makes us different from our closest ape relatives is our habitually bipedal posture. How, when, and why did early humans rise up off their knuckles and stand tall?

I say "stand tall" because there has long been an element of mythic storytelling in hypotheses involving the origins of our kind. We want to know the moment our ancestors went from "dumb monkeys" to "noble apes." (See the book Narratives of Human Evolution for more on this.) As such the origin of bipedalism has often been attributed to the beginnings of other "defining" human characters. Our ancestors stood up to free their hands to gesticulate and carry tools, to allow mothers to carry babies more comfortably, to let them see predators and potential prey in the tall grass of the savanna, &c., &c. &c. The emphasis has long been on why our earliest ancestors stood up, but Ardipithecus ramidus suggests that they were already standing upright when they came down from the trees.

Ardipithecus Ramidus hand

Since the discovery of "Lucy" paleoanthropologists have recognized that the early australopithecines, a diverse group of hominins including both our ancestors and other now-extinct lineages, had their hands in the trees and their feet on the ground. They had long arms with curved fingers suited to climbing in trees yet from the hips down they were adapted to walking bipedally. When the remains of even older hominins were found, like the ~6 million year old Orrorin tugenensis from Kenya and the controversial ~7 million year old hominid Sahelanthropus tchadensis from Chad, they too appeared to posses some traits related to bipedalism. The problem was that these older fossils were very incomplete; Orrorin is represented by a few carnivore-gnawed scraps and Sahelanthropus by a skull and a few teeth. More complete skeletons would be needed to see to what extent early hominins possessed bipedal and arboreal traits. Ardipithecus ramidus does so nicely.

Much like Australopithecus afarensis, Ardipithecus ramidus had upper-body traits that exhibit adaptation to life in the trees while it had relatively broad hips more consistent with bipedal locomotion. The arms of Ardipithecus ramidus were very long (it could put its hands on its knees standing up; take a moment and try to do the same) and it had hands tipped in curved fingers well-adapted to grasping branches (see image to the upper left). It does not appear to have moved through the canopy by swinging from limb to limb, like a gibbon, but instead moved through the trees on all fours, grasping the branches below it rather than hanging from those above.

Ardipithecus ramidus pelvis

The hips of Ardipithecus ramidus, however, suggest that it probably spent a good deal of time walking upright. (See image to the left. Grey reconstruction is Ardipithecus ramidus. Yellow is Australopithecus afarensis.) In knuckle-walking apes like chimpanzees the blades of the pelvis are flat and come up over the back. In Ardipithecus ramidus the blades of the pelvis form are somewhat more bowl-shaped, a shape that helps hold the viscera of the abdomen in place in hominins that were constantly walking upright. The arrangement in Ardipithecus ramidus did not provide as much support as in our own genus, Homo, or even later australopithecines, but it offered more support than the same bones in chimpanzees. (It should be noted, though, that this interpretation is already controversial.)

The femur, or thigh bone, may also provide a crucial clue to the bipedal habits of Ardipithecus ramidus. Based upon the skeletal restoration published in the Science papers the femur this hominin was oriented to meet the knee-joint at an angle. It might not look like it when you view your own legs, but if you could see your own skeleton when you stood up straight you would see the same orientation, only to a greater extent. This, along with the development of muscles between the top of the femur and the hip, are essential to keeping balance while walking upright.

Ardipithecus ramidus foot

This does not mean that Ardipithecus ramidus walked upright all the time or walked like we do, however. It probably only walked upright while on the ground, preferring to move on all fours by grasping while in the trees, and the muscles important to stabilization while walking were not as developed as in later, habitually bipedal hominins. Ardipithecus ramidus also had a very ape-like foot (see image to the left) with a divergent big toe. In our foot our big toe is in line with the rest and assists with the big push-off at the end of a step. Ardipithecus ramidus lacked this adaptation for walking on the ground. Between its foot morphology and lesser development of the hip muscles for balance, Ardipithecus ramidus may have even slightly swayed side to side while walking.

Yet there was an important difference between the foot of Ardipithecus ramidus and that of living chimpanzees and gorillas. The living African apes have flexible feet useful for grasping, almost like a second pair of hands. In monkeys and other primates, however, a particular bone (the os peroneum) embedded within a foot tendon helps keep the foot rigid, especially when jumping from one surface to another. According to the authors of the study, our close ape relatives have lost this "rigid foot" adaptation while our species has retained it. It appears that Ardipithecus ramidus had this "rigid foot" mechanism too, and this relatively simple trait might have had a major effect on its ability to walk on land. Being able to keep a rigid foot while walking on the ground might have been a subtle feature that nevertheless had great importance as early hominins began to walk on the ground more often.


In general, though, it appears that the adaptations that allowed Ardipithecus ramidus to walk upright on the ground were exaptations. Adaptations that its ancestors possessed for life in the trees were advantageous to walking on the ground and were modified to fit a more terrestrial lifestyle. Pre-existing adaptations to life in the trees were put to new use on the ground and began to be shaped by this new mode of life.

But why would Ardipithecus ramidus have walked on the ground so often? What pressures caused the selection of bipedal traits? These questions are difficult to answer, but the scientists behind the descriptive papers hypothesize that Ardipithecus ramidus was a more generalized feeder than living chimpanzees. It did not go as high up into the canopy in search of fruit, and instead ate a wider variety of food more often, something that drew it to the ground. This hypothesis might be able to be tested by looking at what istopes are preserved in the teeth of Ardipithecus ramidus, but even then we can't necessarily be sure we're asking the right questions. I have no doubt these questions will be debated for some time to come.

The hypothesis that Ardipithecus ramidus was arboreally-adapted but did not knuckle-walk, however, is consistent with recent studies that suggest that knuckle-walking was not the ancestral mode of locomotion in the last common ancestor of humans and chimpanzees. In fact, slight differences in the way that gorillas and chimpanzees knuckle-walk may even mean that this "typical" ape mode of locomotion evolved more than once. And while most of the focus has been on Ardipithecus ramidus, the constellation of traits we see in its skeleton may suggest that living chimpanzees are more evolutionarily specialized than we previously thought. What we need to find are early fossil chimpanzees; their side of the family tree is practically blank. Being able to compare early humans with early chimpanzees would tell us much about the evolution of both groups.

There is plenty more that could be said (and certainly will be said) about Ardipithecus ramidus, but the question many people want answered is "How does it fit into our family tree?" The answer is not as straightforward as you might think, and whatever we say now will have to be tested against new discoveries. It will be important to compare even earlier fossil humans and chimpanzees to Ardipithecus ramidus to test what we hypothesize today.

Ardipithecus ramidus is more similar to other early hominins, like australopithecines, than chimpanzees. This makes it one of our early human relatives, but a question remains; was it ancestral to us or does it simply represent the form our true hominin ancestors exhibited at one point in time? Tim White, one of the lead architects of the Ardipithecus ramidus analysis has long favored a straight-line-progression of early hominins, and he slots Ardipithecus ramidus into this sequence. (See his recent essay in The Paleobiological Revolution.)

If White's view is correct, Ardipithecus ramidus would be a chronospecies, or a particular stage in a direct, gradual line of descent that did not have any side branches or splits. This would mean that paleoanthropologists are looking at different forms of a single species at different points in time. As such Ardipithecus ramidus would not have evolved as a result of a speciation event but would instead represent a particular "phase" in a narrow line of hominin evolution. Ardipithecus kadabba transitions to Ardipithecus ramidus which shades into Australopithecus anamensis which turns into Australopithecus afarensis, after which the human evolutionary tree splits between the earliest members of the genus Homo and other australopithecines.

The idea that early hominins shaded into one another in a straight line of descent requires substantial evidence to corroborate. Based upon what we see elsewhere in the fossil record, and even among living species, it is difficult to believe that there were no speciation events that resulted in ancestor species and descendant species living side-by-side for a time. We expect splits, and it may be that what appears to be a straight chain of evolution is only that way because we are still dealing with an incomplete record in terms of time and biogeography. It is also difficult to be sure of direct ancestor-descendant relationships when dealing with extinct organisms, and this is true of hominins just as well as other extinct vertebrates. (White's complaints about "cladists" aside.) We want to know whether this or that early hominin was ancestral to us, but in many cases we cannot know for sure. I have no doubt that there are plenty of other early hominins to be discovered, and as they are found I would expect a "bushier" picture of human evolution to emerge.

Three hypotheses of early hominin evolution
Three hypotheses of early hominin evolution
Top - That there was a straight line of hominin evolution, each "species" being the phase or grade of one true natural species.
Middle - A single line of hominin evolution with a speciation event in the same area in which the earliest Australopithecus split from Ardipithecus ramidus.
Bottom - Ardpithecus ramidus as one of the last members of a more archaic lineage which existed after a speciation event elsewhere in Africa that gave rise to the first Australopithecus. Published in Science.

While the authors of the present study seem to prefer Ardipithecus ramidus as a "chronospecies" between Ardipithecus kadabba and Australipithecus anamensis (a hominin known from fragmentary remains thought to be intermediate between Ardipithecus and Australopithecus afarensis), they do present two alternative hypothesis (though not in much detail). There may have been some sort of speciation event between the last Ardipithecus and the first Australopithecus, either within the same geographical area or outside it, and either of which could falsify the idea that there was just one lineage of hominins evolving in a gradual fashion in one place. It may even be that Ardipithecus ramidus represents a remnant of an earlier evolutionary split among the earliest hominins. Future discoveries will be needed to test these ideas, but at the moment I must admit that the "chronospecies" pattern preferred by White is a little difficult for me to swallow. It would appear to be consistent with the evidence at present, but I very much doubt that all the relevant evidence is in yet.

Arguments over the tempo and mode of evolution aside, the assorted collection of Ardipithecus ramidus fossils are very impressive and will no doubt be important to our understanding of early human evolution for many years to come. While some have said that the new fossils are more important than "Lucy", I think this is a mistake. Ardipithecus ramidus is so impressive because of the mosaic of features it exhibits when compared to other early hominins and living apes (including us). It is best understood as part of an transitional series in which the evolution of particular features can be tracked. If anything, the fossils of Ardipithecus ramidus make the bones of other early hominins more important; by comparing them to each other that we can achieve a better understanding of our own evolutionary heritage.

[To get the papers summarized in this blog post, visit the special Ardipithecus ramidus webpage hosted by Science.]

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Some material presented will contain links, quotes, ideologies, etc., the contents of which should be understood to first, in their whole, reflect the views or opinions of their editors, and second, are used in my personal research as "fair use" sources only, and not espousement one way or the other. Researching for 'truth' leads one all over the place...a piece here, a piece there. As a researcher, I hunt, gather and disassemble resources, trying to put all the pieces into a coherent and logical whole. I encourage you to do the same. And please remember, these pages are only my effort to collect all the pieces I can find and see if they properly fit into the 'reality aggregate'.

Personal Position

Personal Position:
I've come to realize that 'truth' boils down to what we 'believe' the facts we've gathered point to. We only 'know' what we've 'experienced' firsthand. Everything else - what we read, what we watch, what we hear - is what someone else's gathered facts point to and 'they' 'believe' is 'truth', so that 'truth' seems to change in direct proportion to newly gathered facts divided by applied plausibility. Though I believe there is 'truth', until someone representing the celestial realm visibly appears and presents the heavenly records of Facts And Lies In The Order They Happened, I can't know for sure exactly what "the whole truth' on any given subject is, and what applies to me applies to everyone. Until then I'll continue to ask, "what does The Urantia Book say on the subject?"
~Gail Bird Allen

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