Science Current Events | Science News | Brightsurf.com
 

Anthropologist finds explanation for hominin brain evolution in famous fossil

May 08, 2012
TALLAHASSEE, Fla. -- One of the world's most important fossils has a story to tell about the brain evolution of modern humans and their ancestors, according to Florida State University evolutionary anthropologist Dean Falk.

The Taung fossil - the first australopithecine ever discovered - has two significant features that were analyzed by Falk and a group of anthropological researchers. Their findings, which suggest brain evolution was a result of a complex set of interrelated dynamics in childbirth among new bipeds, were published May 7 in the prestigious Proceedings of the National Academy of Sciences.

"These findings are significant because they provide a highly plausible explanation as to why the hominin brain might grow larger and more complex," Falk said.

The first feature is a "persistent metopic suture," or unfused seam, in the frontal bone, which allows a baby's skull to be pliable during childbirth as it squeezes through the birth canal. In great apes - gorillas, orangutans and chimpanzees - the metopic suture closes shortly after birth. In humans, it does not fuse until around 2 years of age to accommodate rapid brain growth.

The second feature is the fossil's endocast, or imprint of the outside surface of the brain transferred to the inside of the skull. The endocast allows researchers to examine the brain's form and structure.

After examining the Taung fossil, as well as huge numbers of skulls belonging to apes and humans, as well as corresponding 3-D CT (three-dimensional computed tomographic) scans, and taking into account the fossil record for the past 3 million years, Falk and her colleagues noted three important findings: The persistent metopic suture is an adaptation for giving birth to babies with larger brains; is related to the shift to a rapidly growing brain after birth; and may be related to expansion in the frontal lobes.

"The persistent metopic suture, an advanced trait, probably occurred in conjunction with refining the ability to walk on two legs," Falk said. "The ability to walk upright caused an obstretric dilemma. Childbirth became more difficult because the shape of the birth canal became constricted while the size of the brain increased. The persistent metopic suture contributes to an evolutionary solution to this dilemma."

The later fusion of the metopic suture is most likely an adaptation of hominins who walked upright to be able to more easily give birth to babies with relatively large brains. The unfused seam is also related to the shift to rapidly growing brains after birth, an advanced human-like feature as compared to apes.

"The later fusion was also associated with evolutionary expansion of the frontal lobes, which is evident from the endocasts of australopithecines such as Taung," Falk said.

The Taung fossil, which is estimated to be around 2½ million years old, was discovered in 1924 in Taung, South Africa. It became the "type specimen," or main model, of the genus Australopithecus africanus when it was announced in 1925.

An australopithecine is any species of the extinct genera Australopithecus or Paranthropus that lived in Africa, walked on two legs and had relatively small brains.

###

Falk conducted the research with Marcia S. Ponce de Leon, Christoph P.E. Zollikofer and Naoki Morimoto of the Anthropological Institute and Museum at the University of Zurich in Switzerland.

Florida State University



More Metopic Suture Current Events and Metopic Suture News Articles

Tarascon Neurosurgery Pocketbook

Tarascon Neurosurgery Pocketbook
by MG Hayden Gephart (Author)


The Tarascon Neurosurgery Pocketbook brings neurologists, neurosurgeons and residents the most convenient and comprehensive pocket reference available today. This concise, organized pocket guide is packed with essential lists, figures, & tables providing instant reminders of hard-to-remember, vital clinical information. This pocket reference guide covers an array of neurosurgery topics including brain tumors. No other Neurologic reference of this kind incorporates neurosurgery, neurology and neuro-critical care in one reference. The Tarascon Neurosurgery Pocketbook is an unmatched resource for neurosurgeons and trainees.

Atlas of Human Anatomy: Including Student Consult Interactive Ancillaries and Guides, 6e (Netter Basic Science)

Atlas of Human Anatomy: Including Student Consult Interactive Ancillaries and Guides, 6e (Netter Basic Science)
by Frank H. Netter MD (Author)


The gold standard of excellence for 25 years, Frank H. Netter, MD's Atlas of Human Anatomy offers unsurpassed depictions of the human body in clear, brilliant detail - all from a clinician's perspective. With its emphasis on anatomic relationships and clinically relevant views, Dr. Netter's work provides a coherent, lasting visual vocabulary for understanding anatomy and how it applies to medicine today.View anatomy from a clinical perspective with hundreds of exquisite, hand-painted illustrations created by pre-eminent medical illustrator Frank H. Netter, MD.Join the global community of medical and healthcare students and professionals who rely on Netter to optimize learning and clarify even the most difficult aspects of human anatomy. Comprehensive labeling uses the international...

Clinically Oriented Anatomy

Clinically Oriented Anatomy
by Keith L. Moore (Author), Anne M. R. Agur (Author), Arthur F. Dalley (Author)


Clinically Oriented Anatomy provides first-year medical students with the clinically oriented anatomical information that they need in study and practice. This best-selling anatomy textbook is renowned for its comprehensive coverage of anatomy, presented as it relates to the practice of medicine, dentistry, and physical therapy. The 7th edition features a NEW-AND-IMPROVED ART PROGRAM to reinforce its position as the primary resource serving the needs of anatomy students during both the basic science and the clinical phases of their studies. Moore is the popular choice for anatomy in many programs, including: medical, dental, physician assistant, chiropractic, podiatry, osteopathic, physical therapy, occupational therapy, kinesiology, and sports medicine.

The 7th edition...

Langman's Medical Embryology

Langman's Medical Embryology
by Thomas W. Sadler PhD (Author)


Langman's Medical Embryology covers embryology for medical, nursing, and health professions students with a strong clinical emphasis. The text is highly valued as a teaching and learning resource for its clinical correlation boxes, summaries, problems to solve, illustrations and clinical images, and clear, concise writing style—all of which make the subject matter accessible to students and relevant to instructors. Online material includes Simbryo—an animation program showing processes, organs, and systems developing in human embryos—as well as review questions and full text online. A separate Faculty Image Bank and PowerPoint presentations are also available.

Clinically Oriented Anatomy, 6th Edition

Clinically Oriented Anatomy, 6th Edition
by Keith L. Moore (Author), Arthur F. Dalley (Author), Anne M. R. Agur (Author)


Clinically Oriented Anatomy, Sixth Edition, provides first-year medical and allied health students with the clinically oriented anatomical information that they need in study and practice. This best-selling textbook is renowned for its comprehensive coverage of anatomy, presented as it relates to the practice of medicine, dentistry, and physical therapy.The Sixth Edition features a modified interior design with new and improved artwork that further enhances the user-friendliness of the text. The clinical Blue Boxes—with topical coverage of health, clinical procedures, physical examination, and development— are now grouped to reduce interruption of text and are categorized with icons to promote easier comprehension of clinical information. The Bottom Line summaries have been refined to...

Gray's Anatomy: The Unabridged Running Press Edition Of The American Classic

Gray's Anatomy: The Unabridged Running Press Edition Of The American Classic
by Henry Gray (Author), T. Pickering Pick (Author), Robert Howden (Author)


The famous, unconditionally guaranteed, durable paperback edition with high-quality paper and binding.

Grant's Atlas of Anatomy, 13th Edition

Grant's Atlas of Anatomy, 13th Edition
by Anne M. R. Agur (Author), Arthur F. Dalley (Author)


A cornerstone of gross anatomy since 1943, Grant's Atlas of Anatomy reaches students worldwide with its realistic dissection illustrations, detailed surface anatomy photos, clinical images and comments, and quick-reference muscle tables. Renowned for its accuracy, pedagogy, and clinical relevance, this classic atlas boasts significant enhancements, including updated artwork, new conceptual diagrams, and vibrantly re-colored illustrations. Clinical material is clearly highlighted in blue text for easy identification.

Sectional Anatomy for Imaging Professionals, 3e

Sectional Anatomy for Imaging Professionals, 3e
by Lorrie L. Kelley MS RT(R) (Author), Connie Petersen MS RT(R) (Author)


An ideal resource for the classroom or the clinical setting, Sectional Anatomy for Imaging Professionals, 3rd Edition provides a comprehensive, easy-to-understand approach to the sectional anatomy of the entire body. Side-by-side presentations of actual diagnostic images from both MRI and CT modalities and corresponding anatomic line drawings illustrate the planes of anatomy most commonly demonstrated by diagnostic imaging. Concise descriptions detail the location and function of the anatomy, and clearly labeled images help you confidently identify anatomic structures during clinical examinations and produce the best possible diagnostic images. Side-by-side presentation of anatomy illustrations and corresponding CT and MRI images clarifies the location and structure of sectional anatomy....

Pediatric Physical Examination-: An Illustrated Handbook, 2e

Pediatric Physical Examination-: An Illustrated Handbook, 2e
by Karen Duderstadt RN PhD CPNP PCNS (Author)


"This handbook serves the needs of undergraduate medical students ,nursing students and is good refresher for Pediatric post graduates." Neel Kamal, Aug14 This portable, photo-rich guide to physical examination for Nurse Practitioners and other primary care providers will help you develop the unique range of skills required to assess children of all ages. System chapters begin with embryological development and review the key developmental stages of childhood. For infants and young children, this step-by-step guide uses the "quiet-to-active" approach favored by pediatric experts and considered more effective for this age-group than the traditional head-to-toe approach used for adults. Other key topics include pediatric mental health assessment and growth and development screening and...

Tarascon Pediatric Outpatient Pocketbook

Tarascon Pediatric Outpatient Pocketbook
by Stephanie L. D'Augustine (Author), Todd J. Flosi (Author)


Completed revised and updated for 2011, the Tarascon Pediatric Outpatient Pocketbook, Second Edition is the essential quick clinical reference for the busy outpatient pediatrician, family physician, or student/resident on a pediatric clinic rotation. This pocket guide includes the latest and most authoritative clinical practice guidelines and is packed with easy-to-understand algorithms, tables, charts, and lists. Covering newborns through adolescents, the meticulously referenced Tarascon Pediatric Outpatient Pocketbook, Second Edition puts the most important but hardest-to-remember facts, treatment options, prognoses and other critical information at your fingertips.

© 2014 BrightSurf.com