The Agricultural Revolution improved farming techniques and changed the way food is produced have resulted in enormous increases in production.
In this way, people were able to increase the percentage of the ecosystem’s biological production that was available for human consumption, and the carrying capacity for humans increased.
Humans have increased their carrying capacity more than 1000-fold since the Agricultural Revolution by channelling progressively larger percentages of the Earth’s biological production to human consumption.
Many anthropologists say that the carrying capacity of humans on the planet without agriculture is about 10 million. This population was reached about 10,000 years ago. At the time, people lived together in small bands of hunters and gatherers. Typically men hunted and fished; women gathered nuts and vegetables.
Obviously, human populations have blown past this hypothetical carrying capacity. By using our brains, our erect posture, and our hands, we have been able to manipulate our environment in ways that no other species has ever done. See more at CK12.org - Agriculture and Human Population Growth.
To learn more about the relationship of Agricultural Revolution and the Earth's carrying capacity for humans, see Human Ecology - Basic Concepts for Sustainable Development.