Dear Colleagues - this is to announce that the following new paper on brains and life history in odontocetes is on-line at http://content.karger.com/ProdukteDB/produkte.asp?Aktion=Ausgabe&ProduktNr=2... Lefebvre, L, Marino, L., Sol, D, Lemieux S, Arshad, S. (2006). Large brains and lengthened life history periods in odontocetes. Brain Behavior and Evolution. 268: 218-228. Abstract Previous work on primates and birds suggests that large brains require longer periods of juvenile growth, leading to reproductive constraints due to delayed maturation. We examined the relationship between brain size and life history periods in cetaceans, a large-brained mammalian order that has been largely ignored. We looked at males and females of twenty-five species of odontocetes, using independent contrasts and multiple regressions to disentangle possible phylogenetic effects and inter-correlations among life history traits. We corrected all variables for body size allometry and separated life span into adult and juvenile periods. For females and both sexes combined, gestation, time to sexual maturity, time as an adult and life span were all positively associated with residual brain size in simple regressions; in multiple regressions maximum life span and time as an adult were the best predictors of brain size. Males showed few significant trends. Our results suggest that brain size has co-evolved with extended life history periods in odontocetes, as it has in primates and birds, and that a lengthened adult period could have been an important component of encephalization in cetaceans. For a reprint please contact me at lmarino@emory.edu Thank you, Lori Marino -- Lori Marino, Ph.D. Neuroscience and Behavioral Biology Program 1462 Clifton Road, Suite 304 Emory University Atlanta, GA 30322 Phone: (404) 727-7582 Fax: (404) 727-7471 When one tugs at a single thing in nature, he finds it attached to the rest of the world. - John Muir