Predation, Landbridges, Technology, Global warming, and the Drake equation.
I've been thinking about who we are, species-wise, where we are coming from, and where we´re going to. In the animal kingdom, I think intelligence is selected for in predators, less so in herbivores and scavengers, and not at all in photosynthesizers. I think scavengers and herbivores intelligence would largely be directed toward escape and avoidance strategies with regard to their predators. Sometime after the origin of cyanobacteria/blue-green algae I imagine a phagocytic cell mutated, and did well due to an abundant ready-made food source, and coincidentally helped thin the photosynthetic herd. The presence of canines in human dentistry pretty well defines what side of that equation homo sapiens falls on. Hunting prey as well as an opposable digit would seem to select for the technological advancement of a predatory species, whether it is defined as a twig dipped in an anthill by a chimp, or the developement of other ´tools´like spears, bow and arrow, and semi-automatic firearms. So I think we´re coming from a predatory background, with some opportunistic gathering thrown in to the mix.
As our species´knowledge and intelligence increases so does our success in hunting, (and gathering). This would likely correlate to larger and more densely distributed populations, which in turn puts more pressure on prey species. So migration, seasonal and otherwise became part of the human condition. About 13,000 years ago our planet underwent a cold snap. An Ice age uncovered the Bering land bridge, which allowed easy access to North and South America by large numbers of us. The availability of large populations of prey species all but guaranteed this migration. An abundance of wooley mammoth, bison, etc. would have produced the Holicene equivalent of the California gold rush. The prizes far exceeded the risks. What are a few sabre-toothed tigers when compared to this bonanza of megafauna. So... as things 'heated up´with the end of the ice age conditions became more lucrative for us, and less so for all that megafauna. As our population and technology increased along with global temperatures and megafauna populations diminished or became extinct, we were able to implement more complex survival strategies, especially regarding agriculture. This developement reflected a sea-change in the human paradigm. We were able toproduce significantly more food than could be reliably hunted and gathered, thus allowing larger human populations to be supported while suffering fewer losses due to short term ecologic events such as drought. Farming also pretty much ended nomadic/migratory lifestyles where climate supported it. This post- Holicene warming period marked mass extinctions of other non-prey species along with a concommittant increase in our own population(s). This pattern of extinction continues unabated to this day. Whether these extinctions are due to man´s activities, global warming , or both is still being debated. Our reliance on animal husbandry for for food exacerbates the issue of rising global temperature through the production of greenhouse gases. It´s been estimated that farm animal production contributes more to the carbon load we pump into the atmosphere than the amount added through our use of diesel and internal combustion engines in transportation.
As our species´knowledge and intelligence increases so does our success in hunting, (and gathering). This would likely correlate to larger and more densely distributed populations, which in turn puts more pressure on prey species. So migration, seasonal and otherwise became part of the human condition. About 13,000 years ago our planet underwent a cold snap. An Ice age uncovered the Bering land bridge, which allowed easy access to North and South America by large numbers of us. The availability of large populations of prey species all but guaranteed this migration. An abundance of wooley mammoth, bison, etc. would have produced the Holicene equivalent of the California gold rush. The prizes far exceeded the risks. What are a few sabre-toothed tigers when compared to this bonanza of megafauna. So... as things 'heated up´with the end of the ice age conditions became more lucrative for us, and less so for all that megafauna. As our population and technology increased along with global temperatures and megafauna populations diminished or became extinct, we were able to implement more complex survival strategies, especially regarding agriculture. This developement reflected a sea-change in the human paradigm. We were able toproduce significantly more food than could be reliably hunted and gathered, thus allowing larger human populations to be supported while suffering fewer losses due to short term ecologic events such as drought. Farming also pretty much ended nomadic/migratory lifestyles where climate supported it. This post- Holicene warming period marked mass extinctions of other non-prey species along with a concommittant increase in our own population(s). This pattern of extinction continues unabated to this day. Whether these extinctions are due to man´s activities, global warming , or both is still being debated. Our reliance on animal husbandry for for food exacerbates the issue of rising global temperature through the production of greenhouse gases. It´s been estimated that farm animal production contributes more to the carbon load we pump into the atmosphere than the amount added through our use of diesel and internal combustion engines in transportation.
