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Furthermore, although it is well established that first molar tooth emergence (movement into the mouth) is correlated with the scheduling of growth and reproduction across primates broadly, its precise relation to solid food consumption, nursing behavior, or maternal life history is unknown. To address these concerns we conducted a photographic study of subadult chimpanzees (\n                    <jats:italic>Pan troglodytes schweinfurthii<\/jats:italic>\n                    ) in Kanyawara, Kibale National Park, Uganda. Five healthy infants emerged their lower first molars (M1s) by or before 3.3 y of age, nearly identical to captive chimpanzee mean ages (\u223c3.2 y,\n                    <jats:italic>n<\/jats:italic>\n                    = 53). First molar emergence in these chimpanzees does not directly or consistently predict the introduction of solid foods, resumption of maternal estrous cycling, cessation of nursing, or maternal interbirth intervals. Kanyawara chimpanzees showed adult patterns of solid food consumption by the time M1 reached functional occlusion, spent a greater amount of time on the nipple while M1 was erupting than in the preceding year, and continued to suckle during the following year. Estimates of M1 emergence age in australopiths are remarkably similar to the Kanyawara chimpanzees, and recent reconstructions of their life histories should be reconsidered in light of these findings.\n                  <\/jats:p>","DOI":"10.1073\/pnas.1218746110","type":"journal-article","created":{"date-parts":[[2013,1,28]],"date-time":"2013-01-28T20:44:44Z","timestamp":1359405884000},"page":"2787-2791","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":83,"title":["First molar eruption, weaning, and life history in living wild chimpanzees"],"prefix":"10.1073","volume":"110","author":[{"given":"Tanya M.","family":"Smith","sequence":"first","affiliation":[{"name":"Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zarin","family":"Machanda","sequence":"additional","affiliation":[{"name":"Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew B.","family":"Bernard","sequence":"additional","affiliation":[{"name":"Freelance Nature Photographer, Merchantville, NJ 08109;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ronan M.","family":"Donovan","sequence":"additional","affiliation":[{"name":"Freelance Nature Photographer, Helena, MT 59602;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amanda M.","family":"Papakyrikos","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, Wellesley College, Wellesley, MA 02481; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin N.","family":"Muller","sequence":"additional","affiliation":[{"name":"Department of Anthropology, University of New Mexico, Albuquerque, NM 87131"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard","family":"Wrangham","sequence":"additional","affiliation":[{"name":"Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2013,1,28]]},"reference":[{"key":"e_1_3_3_1_2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.an.24.100195.001353"},{"key":"e_1_3_3_2_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1558-5646.1989.tb04266.x"},{"key":"e_1_3_3_3_2","doi-asserted-by":"publisher","DOI":"10.1002\/evan.1360010406"},{"key":"e_1_3_3_4_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jhevol.2007.04.007"},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.1038\/414628a"},{"key":"e_1_3_3_6_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1010906107"},{"key":"e_1_3_3_7_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0402635101"},{"key":"e_1_3_3_8_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0906206107"},{"key":"e_1_3_3_9_2","doi-asserted-by":"crossref","unstructured":"Kelley J Schwartz GT (2012) Life-history inference in the early hominins Australopithecus and Paranthropus . 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