Here are the chronological events:
1. <span>humans survived by hunting and gathering.
2. </span><span>the the neolithic revolution occurred,
3. </span><span>people could farm and store a surplus of food,
</span><span>4. advanced civilizations developed
</span>The advancaement in agricultural technology became the turning point in human history because it allow humans to modify food availability in order to sustain our survival, which lead to massive population growth and safety over period of time.
Immigration is a widely practice all over the world and history of humanity, it is part of human culture to move around the world.
The roots of immigration of workers vary in time and places, so it is hard to identify who was to blame for the plight of immigrant workers, to define it we must consider each case and its parties.
Most of the time the plight of immigrant workers is the result of a combination of problems related to people country of origins and the country that receives them.
In the country of origins of immigrants we can blame things such as: bad government, environmental crisis as natural disasters, conflicts as wars or financial and economic problems. This all will motivate the immigration which can them leave workers in hard situations.
On the other side we might blame things in the country that receives the immigrant workers, as the government inaction or the inability to the country legally absorbs these workers, results of national policies for immigration and as well companies and other people who employs this immigrants taking advantage of this situation.
So due to this situation the workers will be prone to work in conditions that might be extremely harmful or danger. We can see as well people and companies that take advantage of this situation and pay low wages or don't respect work laws because this people aren't protect under this umbrella.
Because of no option many immigrant workers will submit themselves to harsh conditions of work in the country they are.
He means it's a devotion to a political party. A commitment to some type of purpose. hope this helps!!