Personnel

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Dean Falk

Early hominids, brain evolution, comparative neuroanatomy, primate behavior & cognitive evolution

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John C. Redmond

Comparative neuroanatomy, Brain lateralization, frontal lobe organization, hominid brain evolution & imunohistochemistry

John Guyer

Casting, 3D reconstruction, morphometrics, hominid brain evolution & anatomical drawing

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Dan White

Cerebellar evolution, Neanderthals, hominid brain evolution & cladistics

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Dean Falk  (dfalk@garnet.acns.fsu.edu)

    My research focuses on early hominids, brain evolution, comparative neuroanatomy, and cognitive evolution (including language origins).  Part of my research is based on data that have been collected from primate skeletal material and endocranial casts in African, European and American museums.  I am fortunate to be a member of the Institute of Human Biology at the University of Vienna, where I collaborate with Professor Horst Seidler and colleagues in the application of medical imaging to the study of middle Pleistocene hominids.  Research on cranial blood flow and australopithecine endocasts has led me to develop the 'radiator theory' of brain evolution, and to question the conventional interpretations of certain fossils such as the early hominid known as "Lucy".  At the moment, my graduate students and I are deeply immersed in reconstructing and re-evaluating many of the endocasts from the early part of the hominid fossil record.

 

Recent Publications

  1. Falk, D., Redmond, J.C., Guyer, J.G., Conroy, G.C., Reicheis, W., Weber, G.W., Seidler, H. (2000) Early hominid brain   evolution: A new look at old endocasts.  J. of Hum. Evol. 38; n. 5, p. 695.

  2. Falk, D. (2000) Primate Diversity. New York. Norton pub., in press.

  3. White, D. and Falk, D. (1999) A quantitative and qualitative reanalysis of the endocranial evidence from the juvenile Australopithecus boisei specimen L338y-6 from Omo, Ethiopia.  Amer. J. Phys. Anthropol., 110:339-406.

  4. Conroy, G.C., Falk, D., Guyer, J., Weber, G.W., Seidler, H. and Recheis, W. (2000)  Endocranial capacity in Sts 71 (Australopithecus africanus) by three-dimensional computer tomography.  Anat. Rec., in press.

  5. Hominid brain evolution: Looks can be deceiving. (1998) Science 280:1714.

  6. Falk, D., Froese, N., Sade, D.S., and Dudek, B.C.  (1999)  Sex differences in brain/body relationships of rhesus monkeys and humans.  J. of Hum. Evol. 36:233-238.

  7. Seidler, H. Falk, D., Stringer, C., Wilfing, H., Muller, G.B., zur Nedden, D., Weber, G., Recheis, W., and J.L. Arsuaga. (1997) A comparative study of stereolithographically modeled skulls of Petralona and Broken Hill: Implications for future studies of middle Pleistocene hominid evolution.  Journal of Human Evolution, 33: 691-703.

  8. Falk, D  (1992) Braindance. Henry Hold and Company.

  9. Falk, D. (1990) Brain Evolution in Homo: The "Radiator" Theory (target article) Behavioral and Brain Science 13:333-344.

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John C. Redmond    (redmond@empireone.net)

     I have recently recevied my Ph.D. in biological anthropology, and am now working as a post-doc in the laboratory of Dr. Todd Preuss at the University of Louisiana at Lafayette with the Cognitive Evolution Group.  Presently, I am utilizing imunohistochemistry procedures to investigate the degree of homology in the frontal lobes of monkeys, apes and humans.  My dissertation research explored the relationship between cerebral and behavioral asymmetries in Hylobates syndactylus (siamangs).  Because siamangs are one of the most tuneful of all primate species, I analyzed and compared leading limb preferences during brachiation (from video tape) under two conditions - while siamangs were singing (believed to be strongly influenced by the right hemisphere of the brain in humans), and while they were silent.  I have also identified cortical asymmetries that were reproduced on siamang endocasts.  In short, my dissertation found that while females exhibit a tendency toward a right leading limb preference during brachiation, male, as a group were significantly more likely to posses a preferred leading limb.  Endocasts analyses supports previous work on anthropoids where a left occipital petalia was most commonly observed followed by a right frontal petalia.

    Separately, I have recently published a paper showing the relationship between principal sulcus length (a sulcus in the frontal lobe of the cerebral cortex), cranial capacity, and performance on delay response tasks (representing working memory) in a variety of Old and New World monkeys.   This paper provides a method for predicting brain size and working memory abilities from the length of the principal sulcus, findings that will be usefull for interpreting the primate paleoneurological record where principal sulci are preserved.  Future and current research in this area consists of uncovering the evolutionary correlates of brain structure and function related to working memory.  To this end, Dan White and I are beginning to look at the possible role of the cerebellum in working memory abilities and how specific anatomical areas of the cerebellum are related to properties of the frontal lobe related to working memory.

    I am also a co-author of a paper entitled "Early hominid brain evolution: A new look at old endocasts" (Journal of Human Evolution, in press).  In this paper, we report new cranial capacities for a number of reconstructed robust australopithecine endocasts and highlight newly discovered neuroanatomical differences between robust and gracile australopithecines (see research). This research may prove important for early hominid taxonomy and will hopefully provide important clues for understanding the cognitive evolution of our ancestors. 

    In my work, I use various computer and analytic techniques. For quantifying endocasts, I employ a 3-dimensional modeling technique that utilizes a 3-space digitizer and reverse engineering software.  I believe this technology will be important in the future because it allows precise and accurate renderings of rare skeletal and fossil materials which can then be archived for further analyses.  I am also very interested in the developing way to enhance the process of learning through interactive media and the internet.  On a personal note, I like to spend time playing guitars, riding my mountain bike and trying my hand at outdoor photography.  But mostly I spend time with my wife and two daughters.

 

Recent Publications

  1. Falk, D., Redmond, J.C., Guyer, J.G., Conroy, G.C., Reicheis, W., Weber, G.W., Seidler, H.  (2000) Early hominid brain   evolution: A new look at old endocasts.  J. of Hum. Evol., 38; n. 5, p. 695.  

  2. Redmond, J.C. and Sansone, A.  (submitted) Brain/body relationships in New and Old World monkeys and apes.  Am. J. Phys. Anthropol. (abstract).

  3. Redmond, J.C. (1999) Cranial capacity and performance on delay response task correlated with principal sulcus length in monkeys. Am. J. Phys. Anthropol. 109: 33-40.

  4. Redmond, J.C. (1999) Brains and behavior in Hylobates.  Abstract; Am. J. Phys. Anthropol.  Suppl. 27:

  5. Neiswander, J.L., Odell, L., & Redmond, J.C. (1995) Intra-Accumbens localization of D1and D2 dopamine receptor subtypes in cocaine induced locomotor behavior of rats.   Brain Research. 671: 201-212.

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John G. Guyer      (jguyer@capital.net)    

    I bring to the field of hominid brain evolution a classical training in gross anatomy, sculpting, technical illustrating, and an interest in neurological processing that derives from a 15 year history as an artist, a  clinician and an administrator in addictions medicine.  My arrival in the field of hominid paleontology follows a sojourn in humanistic studies working in the fields of ethnology and philosophy.  I have applied my skills toward reconstruction technologies that have allowed our team to approach the early hominid fossil record through the re-articulation and reconstruction of a number of cranial fragments and endocasts.  Our results are intriguing and have provoked us to reconsider the phylogenetic relationships of early hominids.

    My dissertation research involves looking at the external neuroanatomy of lesser apes, apes and modern Homo sapiens.  The primary objective of this investigation is to measure the orbital and the orbitolateral surfaces of the frontal lobes and basal aspect of the cerebellum on endocasts of apes and humans.  A secondary objective is to measure the rostral ends of frontal and temporal poles on these same specimens because these regions differ in gracile and robust australopithecines and are therefore of interest from an evolutionary perspective.  This investigation allows for comprehensive analyses within and across humans, gorillas, orangutans, chimpanzees, bonobos, and siamangs in order to compare and contrast the morphology of these regions and formulate hypotheses related to neurological processing.  Investigations utilizing medical imaging technology (PET, fMRI) reveal that humans utilize broader areas of their prefrontal cortex to process semantic aspects of language than previously recognized.  Such studies have also linked the cerebellum to cognitive skills, language production, and the generation of words according to semantic rules.

 

Recent Publications

  1. Conroy, G.C., Falk, D., Guyer, J., Weber, G.W., Seidler, H. and Recheis, W. (2000)  Endocranial capacity in Sts 71 (Australopithecus africanus) by three-dimensional computer tomography.  Anat. Rec., in press.

  2. Falk, D., Redmond, J.C., Guyer, J.G., Conroy, G.C., Reicheis, W., Weber, G.W., Seidler, H. (2000) Early hominid brain   evolution: A new look at old endocasts.  J. of Hum. Evol., 38; n. 5, p. 695. 

Dan White    (sligoabby@aol.com) 

    My research focuses on the interface between the fascinating developments in cognitive neuroscience and the fossilized remains of our ancient hominid ancestors.  In this regard, I have been fortunate enough to conduct research at the American Museum of Natural History in New York, the British Museum (Natural History) in London, and the Musée de l¹Homme in Paris.  My research in Europe was accomplished during the two years that I lived and worked in Grenoble, France.  After completing my PhD I hope to return to France to do research and teach.  At the moment, I am working on a doctoral dissertation with Dr. Falk that concerns the relative expansion and reorganization of the lateral cerebellar hemispheres throughout human brain evolution.

    For most of this century brain researchers interested in the cerebellum have wondered about the phylogenetic and functional implications of the enlarged lateral cerebellar hemispheres in Homo sapiens (Dow, 1942; Leiner et al., 1989).  Research has shown through the years that a phylogenetically new structure, the ventrolateral dentate nucleus, developed in great apes and especially in humans concomitant with the enlarged lateral cerebellar hemispheres.  Some researchers have explained the increase in size of these anatomical structures by relating them to behavioral characteristics of movement, specifically the fine manipulatory and locomotory control demonstrated by higher primates (Matano et al., 1985).  However this explanation is only part of the story.  In fact, the ventrolateral dentate nucleus of the cerebellum appears also to receive and transmit information to and from higher cognitive association areas in the parietal and frontal regions of the higher primate brain (Leiner et al., 1986, 1989; Petersen et al., 1988; Desmond et al. 1998; Le et al., 1998).  This non-motor hypothesis for cerebellar function has motivated brain researchers to take a closer look at the functions of the cerebellum.

    As paleoanthropologists we have the ability to study the evolution of the hominid cerebellum directly from the fossil record.  As a student in Dr. Falk¹s laboratory I have had the rare opportunity to compare and measure extinct and extant hominid and non-human primate endocranial casts in order to test for absolute and relative size changes in the hominid cerebellum, cerebellar asymmetries, and basicranial changes through time.  We hope to publish the results of this research in the near future.

 

Literature cited

  • Desmond JE, Gabrieli JDE, Glover GH (1998) Dissociation of frontal and cerebellar activity in a cognitive task:evidence for a distinction between selection and search. Neuroimage 7(4):368-376.   Dow RS (1942).

  • Cerebellar action potentials in response to stimulation of the cerebral cortex in monkeys and cats.  J. Neurophysiol. 5: 121-136.

  • Le TH, Pardo JV, Hu X (1998) 4 T-fMRI study of nonspatial shifting of selective attention: cerebellar and parietal contributions. J. Neurophysiol. 79(3):1535-48.
  • Leiner H, Leiner A, Dow RS (1986) Does the cerebellum contribute to mental skills. Behavioral Neuroscience: 100,4: 443-454.
  • Leiner H, Leiner A, Dow RS (1989) Reappraising the cerebellum: What does the hindbrain contribure to the forebrain? Behavioral Neuroscience: 103,5: 998-1008.
  • Matano S, Baron G, Stephan H, and Frahm HD (1985a,b) Volume comparisons in the cerebellar complex of primates. Folia Primatol. 44:171-203.
  • Peterson SE, Fox PT, Posner MI, Mintun MA, Raichle ME (1988) Positron emission tomographic studies of the cortical anatomy of single word processing. Nature: 331: 585-589.

 

Recent Publications

  1. White DD (2000 in press) Neocortical and neocerebellar expansion in Paranthropus endocasts and their bearing on basicranial similarities with Homo (abstract). Amer. J. Phys. Anthropol..
  2. White DD and Falk D (1999) A quantitative and qualitative reanalysis of the endocast from the juvenile Paranthropus specimen L338y-6 from Omo, Ethiopia.  Amer. J. Phys. Anthropol. 110:399-406.
  3. White DD (1998) The cerebellum in hominid evolution: Evidence from endocranial casts (abstract) Amer. J. Phys. Anthropol. Supp.26
  4. White DD (1996) Implications of cerebellar morphology on the classification of enigmatic fossil hominds (abstract) Amer. J. Phys. Anthropol. Supp. 22.

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