Because any change early in development affects many later events, it tends to be very disruptive --just like moving the lowest blocks in a Lego structure is more likely to make it fall down than removing a top one. This means that the earlier in development a mutation expresses its effects, the lower the chances that it will endure or get fixed in the population. Thus, the frequency of mutations affecting early development is lower than that of those expressed later on, and thus the earlier in development, the more similar different species are to each other and to their original ancestors.
This explains why ontogeny (development) recapitulates phylogeny (evolution). Corollary: When available, fetal or newborn traits, and not adult ones, ought to be used to classify phylogenetic relationships when genomic information is not available. More.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.