Archaeologists and anthropologists got together to investigate how the Incas could feed well over 500,000 people around the South American ruins of the Myans.
They theorised that local land area could not support enough regular agriculture to feed such a vast number of people concentrated into a relatively localised area of land.
Working together with locals they built a series of rafts and tied these to the local river banks. Locals would simply dive to the river bottom and bring up buckets of mud. Once a raft was covered in a thick layer of mud, plant crops were harvested.
Since the river continually resupplied the key nutrients via the mud crop production was way higher than that which could have been resourced from growing plants on the available land surfaces.
This sustainable agriculture allowed very advanced civilization features of permanency; things such as highways and sanitation and running water. Consider if there was not enough room to grow traditional land based food crops their would certainly have not been room to raise large meat providing animals.
Meat ingestion provided a huge boost to human evolution millennia years ago. It is believed this super concentrated form of protein provided the fundamental building blocks for humans gaining advanced thinking processes such as planning and logic skills.
Whether this is true or not may remain a subject of debate, however today there are simply far far to many humans to feed relying primarily on meat producing animals. Today we have worldwide transportation systems there is absolutely no need to consume any meat producing animal for nutrition or good health.
Today everything the human body requires can usually be supplied by some non meat means often without the growth hormones, steroids and antibiotics to reduce the incidence of disease in livestock.
So do yourself a favor; don't have a Cow, choose to have a carrot instead : )
/ hugz ; )