Results 1 to 4 of 4

Thread: The evolution and development of cranial form in Homosapiens.

  1. #1
    Member
    Join Date
    Aug 2007
    Last Online
    Saturday, April 28th, 2018 @ 05:23 AM
    Ethnicity
    Katarinensische
    Subrace
    Dinarid
    Gender
    Age
    42
    Family
    Single adult
    Posts
    1,243
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    1
    Thanked in
    1 Post

    Post The evolution and development of cranial form in Homosapiens.

    Proc Natl Acad Sci U S A. 2002 Feb 5;99(3):1134-9. Epub 2002 Jan 22.


    The evolution and development of cranial form in Homosapiens.

    Lieberman DE, McBratney BM, Krovitz G.

    Department of Anthropology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA. danlieb@fas.harvard.edu

    Despite much data, there is no unanimity over how to define Homo sapiens in the fossil record. Here, we examine cranial variation among Pleistocene and recent human fossils by using a model of cranial growth to identify unique derived features (autapomorphies) that reliably distinguish fossils attributed to "anatomically modern" H. sapiens (AMHS) from those attributed to various taxa of "archaic" Homo spp. (AH) and to test hypotheses about the changes in cranial development that underlie the origin of modern human cranial form. In terms of pattern, AMHS crania are uniquely characterized by two general structural autapomorphies: facial retraction and neurocranial globularity. Morphometric analysis of the ontogeny of these autapomorphies indicates that the developmental changes that led to modern human cranial form derive from a combination of shifts in cranial base angle, cranial fossae length and width, and facial length. These morphological changes, some of which may have occurred because of relative size increases in the temporal and possibly the frontal lobes, occur early in ontogeny, and their effects on facial retraction and neurocranial globularity discriminate AMHS from AH crania. The existence of these autapomorphies supports the hypothesis that AMHS is a distinct species from taxa of "archaic" Homo (e.g., Homo neanderthalensis).

  2. #2
    Junior Member
    Join Date
    Jun 2004
    Last Online
    Tuesday, July 13th, 2004 @ 06:17 PM
    Subrace
    Nordid
    Location
    usa
    Gender
    Age
    36
    Occupation
    student
    Politics
    Great Ideals
    Religion
    Catholic
    Posts
    34
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    1
    Thanked in
    1 Post

    Post Re: The evolution and development of cranial form in Homosapiens.

    Is human brain size still increasing or is it that this has stopped and a from inside(structure wise/wiring) is taking place?

    You seem like an expert

  3. #3
    Progressive Collectivist
    "Friend of Germanics"
    Skadi Funding Member

    Agrippa's Avatar
    Join Date
    Nov 2003
    Last Online
    Monday, January 31st, 2011 @ 09:22 PM
    Ethnicity
    German
    Subrace
    Atlantid
    Location
    Asgard
    Gender
    Politics
    Progressive Collectivist
    Religion
    Catholic
    Posts
    6,969
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    9
    Thanked in
    9 Posts

    Post Re: The evolution and development of cranial form in Homosapiens.

    I think neither, cause there is no effective selection, positive Evolution any more.

    Thats something which can be just done by Eugenic properly in a modern postindustrial society, because natural selection, if implemented, leads just to contraselection under nowadays circumstances, and social policy without Eugenics as well.

    Brain doesnt just grow, there need to be mutations and a selection for those mutants, that doesnt really happen atm.
    Magna Europa est patria nostra
    STOP GATS! STOP LIBERALISM!

  4. #4
    Funding Member
    "Friend of Germanics"
    Skadi Funding Member


    Join Date
    Sep 2003
    Last Online
    Friday, September 5th, 2008 @ 06:36 AM
    Subrace
    Nordid
    Country
    United States United States
    State
    California California
    Gender
    Family
    Married
    Posts
    4,095
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    17
    Thanked in
    16 Posts

    Post Re: The evolution and development of cranial form in Homosapiens.

    It would seem to me that as a species continues to evolve, after first emerging as a species, brain size would decrease. This is because survival skills would become almost involuntary responses, as birds have instincts. Birds have small brains yet they display complex behavior even compared to mammels. What may have happened is that behavior which once required thought became second nature to them. They became hard-wired for a certain behavior and didn't need such a large brain to think things over.

Similar Threads

  1. Neanderthal Post-Cranial Morphology
    By Dr. Solar Wolff in forum Paleoanthropology
    Replies: 0
    Last Post: Tuesday, January 16th, 2007, 06:07 AM
  2. Cranial Capacity and IQ
    By Waarnemer in forum Bio-Anthropology & Human Variation
    Replies: 10
    Last Post: Sunday, April 30th, 2006, 03:43 PM
  3. Determining Cranial Volume
    By cosmocreator in forum Physical Anthropology
    Replies: 2
    Last Post: Saturday, December 4th, 2004, 08:25 AM
  4. Human Evolution: Evolution and the Structure of Health and Disease
    By Frans_Jozef in forum Paleoanthropology
    Replies: 2
    Last Post: Saturday, November 6th, 2004, 07:39 PM
  5. Facial & Cranial Shapes
    By BodewinTheSilent in forum Physical Anthropology
    Replies: 23
    Last Post: Sunday, December 29th, 2002, 11:03 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •