Related Experiment Video
Updated: Aug 17, 2026

Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras
Published on: May 31, 2014
Changes in embryonic development associated with long-term selection for high growth rate in Japanese quail
1Swedish University of Agricultural Sciences, Department of Animal Physiology, Uppsala.
Abstract:
Selection for rapid growth in the quail resulted in a changed growth pattern of the embryo and the extra-embryonic membranes (the yolk sac and allantois). The early part of the incubation period was characterized by a reduced embryo weight and a more rapid early development of the extra-embryonic membranes. These changes were followed by an increased growth rate of the embryo. The increased growth rate was apparently linked to the more rapid early development of the extra-embryonic membranes. Thus, the growth rate was most likely restricted by the capacity to absorb and utilize yolk. It also appears that at least part of the increase in growth rate was made possible by the change in the early embryonic growth pattern.
Related Concept Videos
Determination
Types of Selection
Limits to Natural Selection
Background and Environment Affect Phenotype
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...

