Wednesday, October 27, 2010

Agriculture's Impact on Human Population Growth

When walking into a supermarket, we can choose from a variety of foods and flavors to stimulate our taste buds. In fact, we are so spoiled that we can even decide which brand of a certain product we prefer. Unfortunately, humanity has not always been so lucky. Our population began small and grew very gradually for a long time. The advent of agriculture allowed for this growth in population. Around 10,000 years ago humanity switched from hunter gathering to farming. They began domesticating plants and animals to have a more stable food source. This change allowed for many significant changes in the way humanity existed on this planet. Most notably, agriculture has caused a rapid increase in the size of our population.

Around 10000 years ago, before the shift to agriculture, our population consisted of about only 2 or 3 million individuals. 2000 years ago, however, our population had grown staggeringly to 250 million. Today our population exceeds 6 billion. Technology and improvements in health care are partly responsible for this drastic change, but humanity’s switch to agriculture started this major change.

The effect of the agricultural revolution on human population growth is represented by the following graph:

The switch to agriculture was brought on by necessity and not chance. The human population had stagnated due to a lack of food. Domestication solved this problem. Farming and raising animals produced more food in a smaller space then did hunting and gathering. Wild animals roamed and edible plant life could never be guaranteed. When domestication began food sources stayed near the population. Rather than having to constantly relocate for food, groups could survive with a supply of food near at hand. Also, farming allowed for food to be stored and used at later times if alternative food sources ran short. These factors would allow for our population size to increase dramatically.

The stable supply of food allowed for early humans to have a greater chance of survival due to be more fully nourished. The roaming groups became more settled. This meant that a community could develop and such a society would eventually begin to protect one another from starvation and the wild. Being settled meant a group could learn one area and grow familiar with it rather than having to be constantly on alert. This comfort with the environment would allow people to live longer lives in less relative danger.

A growth in agriculture was necessary to allow the population to continue growing. Instead of random circumstances creating a single case in which agriculture appeared and then spread, evidence shows that agriculture began to pop up in many places around the world. Plant domestication, at least, started in around ten separate areas. This shows how it was a necessary adaptation by humanity to continue population growth.

It is clear that the development of agriculture has allowed for the human species to become what it is today. The attainment of a reliable and consistent food source allowed for the increased population growth of our ancestors. This increase in population allowed for the evolution of human beings to take an interesting turn; with a newfound element of stability, the sophistication of technology, health care, and culture became possible.

Sources:

http://www.springerlink.com/content/m12v36v06608277g/

Our Origins, by Clark Spencer Larsen

Wednesday, October 6, 2010

Climate, Agriculture, & Evolution

The evolution of human beings has been a long process that has gotten us to where we are today. Humans of today have evolved greatly from our ancestors, from hunting, to tools, to planting, to medicines, to machines, to rapidly growing technology, and it continues on. Around 10,000-13,000 years ago, our ancestors underwent a major change in life style and behavior. The transition from being hunter-gatherers to farmers was a huge step in history and has caused many changes in health, habits, way of living, and medicine. This development in human history has been called the Neolithic Revolution were humans learned to domesticate animals, cultivate crops, and build tools (historyworld). Scientists explain this phenomenon due to the change in climate. Around 15,000 years ago, the last Ice Age ended; thus causing more abundant plants to grow (AMBIO). This serge in plant life lead to annual plants to cycle seasonally, leaving dormant seeds. With the right soil, seeds, and weather, hunter-gatherers liked the idea of settling down and farming emerged.

The climate change also created specialization of certain crops in certain geographical locations. For example, these crops are very popular to produce in a special place; maize in Mexico, potatoes in the Andes, and rice from the banks of the Yangtze River (AMBIO). Since then, the processes and systems of agricultural procedures have advanced over time to be more efficient and abundant.

Not only did the climate boom the start of agricultural practices, but still today and in the future, the climate will continue to affect farming. The challenges we have had to face and continue to face include; increasing temperature, changes in environment conditions, and photoperiod… all of which affect plant life (Slater). Photoperiod means the duration of an organism's daily exposure to light, considered especially with regard to the effect of the exposure on growth and development (dictionary).

Basically, humans will need to proceed adapting to the changes of the climate. Like in the Neolithic Revolution, humans could live more comfortably because of the new temperate regions that were created. But, the animals that hunter-gatherers prayed on could not adjust to the new climates and had to move to cooler regions (historyworld). For example, the bison and mammoths (which became extinct due to the climate change) moved away while the humans adapted to the temperate zone and stayed there. Also in the temperate zone, plants grew easily. The humans decided to band the hunting of the few bison around and stuck to putting in the time to cultivate food and adapted to the new way of life.

Even though in reality hunter-gatherers had better health compared to when cultivation first began, agriculture has changed the lives of humans. Agriculture has evolved and will keep changing through out time due to the ever-changing climate. From the Ice Age, to temperate regions, to the theory of global warming, farmers today have to keep up with whatever climate is thrown at them to produce food. “Climate change is likely to increase the unreliability of farming systems”(Slater). But this statement is untrue, as humans have proven to adapt and make any changes to technology and procedures to continue improving and producing food that sustains the populations’ food supply.

Sources:

AMBIO: A Journal of the Human Environment 37(sp14):498-501. 2008. http://www.bioone.org/doi/full/10.1579/0044-7447-37.sp14.498.

Slater, Rachel. Climate Change: Implications for DFID’s Agriculture Policy. March 2008.

http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ab63

http://www.thefreedictionary.com/photoperiod