The first agricultural revolution started in 2000 BC. People slowly started to stop hunting and gathering and started domesticating.
Mesoamerica: Squash,Peppers,Cotton,Potato Nile Valley: Yam,African Rice,Coffee Mesopotamia: Barley,Oats,Rye Indus Valley: Wheat Bread, Olives Huang He RIver Valley: Rice, Soy Beans
The Second Agricultural revolution started in the 1700's and carried out into the 1900's. This revolution was at the same time as the industrial revolution so people started using animals and tools and machines to do there work instead of doing it all by hand.
The third agricultural revolution started in the 19th century and is still going on today. This is the revolution that started using biotechnology for crops and animals. This is also the time that tractors started becoming more advanced and using GPS technology to farm on there own.
This is a picture of how gps technology can farm crops on its own.
Gmo stands for genetically modified crops and these crops are designed to produce more on a harvest so smaller country's can produce more to grow there population.
As you can see the gmo crops grow a lot faster than conventional crops because they were modified to grow faster and bigger than conventional seeds
The downside to having gmos is that a lot of companies want you to keep buying their gmo seeds so they don't let you reuse the seeds. Whenever you make a new seed you own it.