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Saltación y estasis: un modelo de crecimiento humano
M Lampl1, J D Veldhuis, M L Johnson
1Department of Anthropology, University of Pennsylvania, Philadelphia 19104.
Science (New York, N.Y.)
|October 30, 1992
Resumen
El crecimiento humano ocurre en brotes repentinos, no continuamente. La longitud del bebé aumenta en ráfagas de 0,5-2,5 cm, intercaladas con períodos de no crecimiento, desafiando la visión tradicional del desarrollo constante.
Área de la Ciencia:
- Crecimiento y desarrollo pediátrico.
- Fisiología Humana Fisiología Humana.
- Biología del desarrollo Biología del desarrollo.
Sus antecedentes:
- Los modelos tradicionales ven el crecimiento humano como un proceso continuo con cambios de velocidad relacionados con la edad.
- El crecimiento infantil a menudo se representa como una progresión constante y lineal.
Objetivo del estudio:
- Investigar el patrón de aumento de la longitud del bebé humano durante los primeros 21 meses.
- Para determinar si el crecimiento infantil es un proceso continuo o se produce en eventos discretos.
Principales métodos:
- Se recogieron medidas de longitud en serie de 33 bebés normales (19 hembras, 12 machos) durante 21 meses.
- Las frecuencias de medición variaron: semanalmente (n=10), semanalmente (n=18) y diariamente (n=3).
Principales resultados:
- Se encontró que el crecimiento de la longitud del bebé era discontinuo, ocurriendo en chorros saltatorios aperiódicos.
- Estas explosiones de crecimiento oscilaron entre 0,5 y 2,5 cm de amplitud.
- Los brotes de crecimiento fueron separados por intervalos de no crecimiento medible, que duraron de 2 a 63 días.
Conclusiones:
- El crecimiento de la longitud del bebé es un proceso saltatorio, caracterizado por ráfagas incrementales que ponctuan los períodos de estasis.
- Aproximadamente el 90-95% del desarrollo infantil normal ocurre durante los intervalos libres de crecimiento.
- Esto desafía el modelo de crecimiento continuo, destacando un patrón claramente basado en brotes en el desarrollo humano temprano.
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