The key points from this module are:
Variations are generated from modularity and molecular parsimony.
Molecular parsimony is also called a "small toolkit" in developmental Biology.
DNA of a human and chimpanzees are nearly identical.
The difference is not in the alleles of protein-coding genes, but in sequences that decide where, when and how much the genes are activated.
Heterotopy- Change in location
Heterochrony- Change in time
Heterometry- Change in amount
Heterotypy- Change in kind
Heterotopy is an evolutionary change in the spatial arrangement of an animal's embryonic development.
Heterochrony is a shift in the relative timing of two developmental processes.
Developmental constraints can be grouped into:
Polyphenisms are adaptations in which a genome is associated with discrete alternative phenotypes in different environments.