title: New perspectives in early human development.
abstract: A new hypothesis is presented concerning the maturation of the human nervous system and the duration of pregnancy. It has been found that many neural functions characteristic of the fetus continue after birth until a major transformation takes place at the end of the second postnatal month. From a comparative perspective the duration of pregnancy in man is relatively short among primates. An explanation may be found in metabolic constraint. The special energy demands of a large fetal nervous system and the build-up of a subcutaneous fat deposit may have prevented a proportional prolongation of pregnancy during evolution of hominids.
mesh_terms: D000818:Animals; D005075:Biological Evolution; D001724:Birth Weight; D001835:Body Weight; D002657:Child Development; D005314:Embryonic and Fetal Development; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008017:Life Expectancy; D008954:Models, Biological; D009420:Nervous System / Q000196:embryology / Q000254:growth & development; D011247:Pregnancy; D012641:Selection, Genetic; D013997:Time Factors