The Holocene began about 11,700 years ago, after the end of the ice age. The term is a geological term. That happened to be just about the same time that people began to shift from a nomadic hunter-gatherer society to one that investigated and eventually established agriculture. In that brief 12,000 years since then people have made an enormous impact on the planet. Nobel laureate and atmospheric chemist Paul Crutzen popularized the term Anthropocene in 2000 and it now has appeared in some 200 scientific articles. Geologists tend to object to the term and remark that the taxonomy is geological and there is no obvious geological evidence as to the start of a new era. Because this is a nebulous term and not yet completely established in the scientific literature, the exact beginning is unclear.
Whatever is the actual case, the term has caught on and in a new study by Will Steffen and others, 16 Jan 2015, Science, on planetary boundaries, the scope of the human impact is illustrated in a graphic that depicts the outer limits of a number of potentially limiting factors on human survival.
Increasingly the accelerated growth we are currently undergoing in a wide range of variables adds to the concept that the Anthropocene is an era of human dimensions that hare having a singularly strong impact on the resource base of the human civilization. This slideshow is from the IGBP Secretariat and depicts a series of changes since 1750.
The long-term implications of these changes in an economic and ecological environment are ominous. For more information, this site is intriguing: