Experimental Blog # 146

Quotations and notes from "The Last Lost World - Ice Ages, Human Origins, and the Invention of the Pleistocene" by Lydia V. Pyne and Stephen J. Pyne

"As a geologic epoch, the Pleistocene lasted from approximately 2.6 million to 10,000 to 12,000 years ago. It includes an ice age, ...Earth's fifth great extinction event{the Toba eruption 73,000 to 71,000 years ago}, and the appearance and evolution of the hominins." "but Earth did not re-lay its tectonic tiles in any major way during the epoch."

There are 3 cycles{or "orbital forcings"}, orbital stretching, axis tilting, and axis wobbling, which coincide in extremely complex ways to cause Ice Ages. "80 percent of the Pleistocene was glacial, and no interglacial lasted more than 12,000 years."

"The saga of Homo was not unique within the Pleistocene for its evolutionary experience was characteristic of the times. What happened to hominins .. happened to clades of other taxa ..", such as the African bovids and the elephantids -- the proboscideans.

"An estimated 210 skulls of paleohumans exist".. Apparently in 8 species, so far.
"The earliest tendencies toward the modern sapients probably appeared 500,000 years ago in Africa with clear definitions both anatomical and genetic evident between 100,000 and 200,000 years ago."

"Some 22,000 years ago the last glacial reached its maximum ... But a consensus places the general collapse at 11,500 to 14,500 years ago."

"Between 3,000 and 50,000 years ago, some two-thirds of mammal genera and half of all species that weighed more than roughly one hundred pounds went missing."
"...most of the mammalian biomass in the world today is either human{40 megatons of carbon} or human domesticates{100 to 120 megatons of carbon}, while wild vertebrates claim only 5 megatons."

"The arts and humanities can no longer claim - even pretend to claim - that they can make valid statements about the material world and how it works. .. But philosophy, literature, and history can help explain how the sciences work. .. They can illuminate how we might understand and express the practice of knowing, and how we come to a felt sense of who we are and how we should behave."

Science "cannot, unaided, address what it means to live, what makes a life worth living, what purpose spans the narrative of a life or of humanity. It cannot say why a society should even engage in this kind of inquiry."