Was human evolution driven by Pleistocene climate change?

Modern humans are probably a product of social and anatomical preadaptations on the part of our Miocene australopithecine ancestors combined with the increasingly high amplitude, high frequency climate variation of the Pleistocene. The genus Homo first appeared in the early Pleistocene as ice age climates began to grip the earth. We hypothesize that this co-occurrence is causal. The human ability to adapt by cultural means is, in theory, an adaptation to highly variable environments because cultural evolution can better track rapidly changing environments than can genes. High resolution ice and sediment cores published in the early 1990s showed the last ice age was characterized by high amplitude millennial and submillenial scale variation, exactly the sort of variation mathematical models suggest should favor a costly capacity for culture. More recent cores suggest that over the last several 100 thousand year glacial cycles the amount of millennial scale variation has increased rather dramatically in parallel with increases in hominin brain size and sophistication of the artifacts they made

Why Possibly Language Evolved

Human language has no close parallels in other systems of animal communication. Yet it is an important part of the cultural adaptation that serves to make humans an exceedingly successful species. In the past 20 years, a diverse set of evolutionary scholars have tried to answer the question of how language evolved in our species and why it is unique to us. They have converged on the idea that the cultural and innate aspects of language were tightly linked in a process of gene-culture coevolution. They differ widely about the details of the process, particularly over the division of labor between genes and culture in the coevolutionary process. Why is language restricted to humans given that communication seems to be so useful? A plausible answer is that language is part of human cooperation. Why did the coevolutionary process come to rest leaving impressive cultural diversity in human languages? A plausible answer is that language diversity functions to limit communication between people who cannot freely trust one another or where even truthful communications from others would result in maladaptive behavior on the part of listeners

The Origins of Options

Most research on decision making has focused on how human or animal decision makers choose between two or more options, posed in advance by the researchers. The mechanisms by which options are generated for most decisions, however, are not well understood. Models of sequential search have examined the trade-off between continued exploration and choosing one’s current best option, but still cannot explain the processes by which new options are generated. We argue that understanding the origins of options is a crucial but untapped area for decision making research. We explore a number of factors which influence the generation of options, which fall broadly into two categories: psycho-biological and socio-cultural. The former category includes factors such as perceptual biases and associative memory networks. The latter category relies on the incredible human capacity for culture and social learning, which doubtless shape not only our choices but the options available for choice. Our intention is to start a discussion that brings us closer toward understanding the origins of options

A Dynamic Analysis of American Socio-Political History. A Review of Ages of Discord: A Structural Demographic Analysis of American History by Peter Turchin (Beresta Books, 2016)

A Review of Ages of Discord: A Structural Demographic Analysis of American History by Peter Turchin (Beresta Books, 2016

Cultural Innovations and Demographic Change

Demography plays a large role in cultural evolution through its effects on the effective rate of innovation. If we assume that useful inventions are rare, then small isolated societies will have low rates of invention. In small populations, complex technology will tend to be lost as a result of random loss or incomplete transmission (the Tasmanian effect). Large populations have more inventors and are more resistant to loss by chance. If human populations can grow freely, then a population-technology-population positive feedback should occur such that human societies reach a stable growth path on which the rate of growth of technology is limited by the rate of invention. This scenario fits the Holocene to a first approximation, but the late Pleistocene is great puzzle. Large-brained hominins existed in Africa and west Eurasia of perhaps 150,000 years with, at best, slow rates of technical innovation. The most sophisticated societies of the last glacial period appear after 50,000 years ago and were apparently restricted to west and north-central Eurasia and North Africa. These patterns have no simple, commonly accepted explanation. We argue that increased high-frequency climate change around 70,000–50,000 years ago may have tipped the balance between humans and their competitor- predators, such as lions and wolves, in favor of humans. At the same time, technically sophisticated hunters would tend to overharvest their prey. Perhaps the ephemeral appearance of complex tools and symbolic artifacts in Africa after 100,000 years ago resulted from hunting inventions that allowed human populations to expand temporarily before prey over exploitation led to human population and technology collapse. Sustained human populations of moderate size using distinctively advanced Upper Paleolithic artifacts may have existed in west Eurasia because cold, continental northeastern Eurasia–Beringia acted as a protected reserve for prey populations

2009,21: How corporate cultures coevolve with the business environment : the case of firm growth crises and industry evolution

This paper shows how cognitive human dispositions that take effect at the level of an individual firm’s corporate culture have repercussions on an industry's evolution. In our theory, the latter is attributable to evolving corporate cultures coupled with changes in a firm's business environment. With the help of a formal model of evolving corporate cultures, we demonstrate how firms can establish a cooperative cultural regime that yields competitive advantages in an innovative, fast changing environment. Depending on within-firm social learning processes and cognitive constraints of human agents, organizations then reach a critical cognitive firm size in their development beyond which the level of cooperation deteriorates rapidly they systematically face a growth crisis. Organizations successful in such an environment and reaching a critical technological size may, however, reap economies of scale in a later, mature and stable business environment with altered corporate culture. Furthermore, we relate these findings to empirical evidence on firm survival and performance in different industries, the evolution of organizational structures, technological advancements in production technologies, and identify some determinants of market structures. -- Industry Evolution ; Critical Firm Sizes ; Firm Growth ; Corporate Culture ; Human Cognitio

Book reviews

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44496/1/10745_2004_Article_BF00888568.pd