History Paleoneurobiology

primate skull series

humans have had long interest in brain , functions. first recorded study of brain , functions papyrus text written ancient egyptians during 17th century bce. document details 48 medical ailments , makes references how deal head wounds. later in 6th century bce ancient greeks began focus on studies of brain , relationship between optic nerve , brain. studies of brain evolution, however, did not come until later in human history.

comparative anatomy began emergence in latter part of 19th century. 2 main views of life sprung forth; rationalism , transcendentalism. these formed basis thought of scientists in period. georges cuvier , Étienne geoffroy st. hilaire leaders in new field of comparative anatomy. cuvier believed in ability create functional morphology based on empirical evidence. stressed function of organ must coincide form. geoffroy, in contrast, put heavy emphasis on intuition method of understanding. thought based on 2 principles: principle of connections , principle of unity of plan. geoffroy 1 of first homologies in organs across species, though believed evidence of universal plan rather descent modification.

the late part of 19th century in comparative anatomy heavily influenced work of charles darwin in on origin of species in 1859. work changed views of comparative anatomists. within 8 years of darwin s release of origin of species, views on descent common ancestor accepted. led shift in trying understand how different parts of brain evolved. next major innovation helped bring paleoneurobiology microscope. although microscope invented in 17th century, used in biology in beginning in late 19th century. techniques of observing brain cells under microscope took long time refine. in 1873, tool in hand, camillo golgi began cellularly detail brain , employ techniques perfect axonal microscoping. ludwig edinger took advantage of , came new branch of anatomy called comparative neuroanatomy. edinger held vertebrates evolved in linear progressive series. thought changes in brain based on series of additions , differentiations , highly, complex brains were encephalized. period of 1885-1935 explosion of ideas in comparative neuroanatomy. era culminated in publication of comparative anatomy of nervous system arienns, kappers, huber, , cosby. paper influenced tilly edinger , later became founder of paleoneurobiology.

tilly edinger

ottilie tilly edinger born in frankfurt, germany in 1897. father ludwig edinger, himself pioneer in comparative neurology, provided tilly invaluable exposure field , scientific community @ large. tilly had many private tutors before attending schiller-schule, secondary school girls in frankfurt @ time. tilly edinger continued schooling university studies in zoology, geology, , paleontology. while preparing doctoral dissertation, edinger encountered natural brain endocast of nothosaurus, marine reptile mesozoic era. edinger s first paper, published in 1921, centered on characteristics of nothosaurus specimen. prior publication of work, inferences evolution of vertebrate brain made exclusively through comparative anatomy of extant fish, amphibian, reptile, bird, , mammal brains. tilly edinger s background in neurology , paleontology paved way integrate comparative anatomy , stratigraphic sequence, introducing concept of time neurology , creating field of paleoneurobiology. field formally defined publication of die fossilen gehirne (fossil brains) in 1929 compiled knowledge on subject had been scattered in wide variety of journals , treated isolated events.

while still in germany, edinger began studying extant species paleoneurobiological perspective making inferences evolutionary brain development in seacows using stratigraphic , comparative anatomical evidence. edinger continued research in nazi germany until night of november 9, 1938 when thousands of jews killed or imprisoned in became known kristallnacht. although visa not available immigration united states, of friends , colleagues valued work, edinger able immigrate london translated german medical texts english. visa quota number called , able immigrate united states took on position research fellow @ harvard s museum of comparative zoology.

her contributions field of paleoneurobiology include determining extent endocasts reflect anatomy of ancient brains, adequacy of comparative anatomy interpret brain evolution, ability of brain endocasts predict lifestyles of extinct organisms, , if brain size has increased on geological time; topics still being explored today. in later years, edinger corresponded next generation of paleoneurobiologists, insured work 50-year career continued future. pinnacle accomplishment of career compilation of annotated bibliography of paleoneurobiological papers published between 1804 , 1966. bibliography, paleoneurology 1804-1966, completed , published colleagues posthumously in 1975 due untimely death of edinger injuries sustained during traffic accident in 1967.

conflict between holloway , falk

paleoneurobiologists ralph l. holloway , dean falk disagree interpretation of depression on australopithecus afarensis al 162-28 endocast. holloway argues depression result of lipping @ lambdoid suture , sulcal patterns indicate cerebral organization moving toward more human pattern, while falk insists depression lunate sulcus in position indicative of ape-like sulcal pattern. debate between these 2 scientists not hinged solely on al 162-28 endocast, rather extends australopithecine fossils, holloway insisting on presence of hominid sulcal features, , falk maintaining features pongid in nature. debate between holloway , falk intense between 1983 , 1985, published 4 papers on identification of medial end of lunate sulcus of taung endocast (australopithecus africanus), further strengthened division between each scientist s respective opinion. although there have been no definitive conclusions fossils in question, many techniques created or critically analyzed , refined result of conflict. these new techniques in endocast analysis included use of stereoplotting transfer sulci between differently shaped endocasts, measurement of indexes photographs rather directly specimens, , confounding of measurements taken directly specimens , taken photographs.