Evolution
Comparing the structure of the olfactory bulb among vertebrate species, such as the leopard frog and the lab mouse, reveals that they all share the same fundamental layout (five layers containing the nuclei of three major cell types; see "Anatomy" for details), despite being dissimilar in shape and size. Of note, a similar structure is shared by the analogous olfactory center in the fruit fly Drosophila melanogaster, the antennal lobe. One possibility is that vertebrate olfactory bulb and insect antennal lobe structure may be similar because they contain an optimal solution to a computational problem experienced by all olfactory systems and thus may have evolved independently in different phyla.
"The increase of brain size relative to body size—encephalization—is intimately linked with human evolution. However, two genetically different evolutionary lineages, Neanderthals and modern humans, have produced similarly large-brained human species. Thus, understanding human brain evolution should include research into specific cerebral reorganization, possibly reflected by brain shape changes. Here we exploit developmental integration between the brain and its underlying skeletal base to test hypotheses about brain evolution in Homo. Three-dimensional geometric morphometric analyses of endobasicranial shape reveal previously undocumented details of evolutionary changes in Homo sapiens. Larger olfactory bulbs, relatively wider orbitofrontal cortex, relatively increased and forward projecting temporal lobe poles appear unique to modern humans. Such brain reorganization, beside physical consequences for overall skull shape, might have contributed to the evolution of H. sapiens' learning and social capacities, in which higher olfactory functions and its cognitive, neurological behavioral implications could have been hitherto underestimated factors."
http://www.nature.com/ncomms/journal/v2/n12/full/ncomms1593.html
Read more about this topic: Olfactory Bulb
Famous quotes containing the word evolution:
“Historians will have to face the fact that natural selection determined the evolution of cultures in the same manner as it did that of species.”
—Konrad Lorenz (19031989)
“Like Freud, Jung believes that the human mind contains archaic remnants, residues of the long history and evolution of mankind. In the unconscious, primordial universally human images lie dormant. Those primordial images are the most ancient, universal and deep thoughts of mankind. Since they embody feelings as much as thought, they are properly thought feelings. Where Freud postulates a mass psyche, Jung postulates a collective psyche.”
—Patrick Mullahy (b. 1912)
“The more specific idea of evolution now reached isa change from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity, accompanying the dissipation of motion and integration of matter.”
—Herbert Spencer (18201903)