Related Experiment Video
Updated: Mar 1, 2026

Quantifying Learning in Young Infants: Tracking Leg Actions During a Discovery-learning Task
Published on: June 1, 2015
Evidence of saltatory growth in infancy
1Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
Abstract:
Auxological measurements were taken weekly (n = 10), semi-weekly (n = 20), and daily (n = 3) during the first 21 months of life on a sample of normal infants (21 females and 12 males). The serial length measurements are reported. All subjects grew in length during episodic growth saltuses of short duration, with amplitudes of 0.5-2.0 cm during measurements intervals (1 day to 1 week), separated by periods of no measurable growth (2 days to 2 months). The periods of stasis between growth episodes are not positively associated with illness (P = 0.000). These data support the hypothesis that normal human growth during the first 2 years proceeds by pulsatile growth saltuses of substantial amplitude and rapid duration punctuating static intervals. Individual variability in the amplitude and frequency of growth saltuses may account for variation in attained length and growth velocity. © 1993 Wiley-Liss, Inc.
Related Concept Videos
Language Development
The critical period for language acquisition suggests that the ability to acquire language is at its peak early in life. As people age, this proficiency decreases. Language development begins very...
Piaget's Stage 1 of Cognitive Development
Exploration...
Changes in the Appendicular Skeleton with Age
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
The Nativist Approach

