What did most freed slaves do during the period immediately following the civil war

One of the immediate aftermaths of the civil war by slaves was that slaves in the South seized land from their slave owners; however federal troops returned the land to the white owners. Hundreds and thousands of slaves freed after the civil war after the civil war died out of diseases and hunger after being liberated. Union soldiers neglected freed slaves who faced widespread outbreaks of cholera and smallpox while others starved to death.  It is estimated that a quarter of the four million slaves died either out of diseases or starvation. Several slaves knew nothing except for their lives of servitude on the plantations and, with their newfound freedom, couldn't find new opportunities thus opted to remain on these farms.

genetics is the study of how dna works, the methodologies defining the new recent technologies allow scientist to have a panoramic view of the entire dna landscape, especially how genomes interact with their environment, including off course, factors outside their organisms.

thus is very possible the existence of both scenarios, where populations of isolated individuals have different genetic traits, and share traits related to genetic mutation, due rats can easily travel overseas using human transport channels. so scientists could get a vast number of data, including human interaction, evolution of rodents, health development, spread of infections, development of new organisms, how genomes evolve in different environments and so on.

a. poison gas was sprayed over battlefields by airplanes to weaken enemy positions before major attacks.