- Evolution (2nd edition);
- Photocatalysis: science and technology;
- Peter Gluckman, Alan Beedle, Tatjana Buklijas, Felicia Low, and Mark Hanson.
First, the genetic variations that take place in living things are random variations. Second, the genetic variations are small and cause little effect relative to a given population. Over time, these small genetic variations lead to the gradual development of a species rather than the sudden development of a species. Darwin proposed that variations appear without direction and without design. He assumed that among inherited traits, some traits were better than others.
If an inherited trait provided an advantage over another, it would provide a reproductive advantage to the bearer of the trait. This concept is called the survival of the fittest. The fitness implied is reproductive fitness; that is, the ability to survive in the environment and propagate the species.
Principles of human evolution
Natural selection serves as a sieve to remove the unfit from a population and allow the fittest to reproduce and continue the population. Searle, In essence, although I agree with many of their conclusions and criticisms of extant theory, in my estimation their paper is unlikely to change many minds one way or the other. They do an impressive job of exposing a species of modern synthetic logic in Boyd and Richerson and Tomasello by showing essentially that when either camp speaks of evolution, genes, or adaptation in general, they presuppose a neo-Darwinian metatheory — even when they speak of culture.
However, the shortcomings in CET and SIT are also shortcomings to the extent that the EES is taken to be a more adequate general evolutionary framework than what, for example, Wray and colleagues, in a defense of neo-Darwinism, term standard evolutionary theory. Here I think Packer and Cole might be in some difficulty. First though, let me underscore, paraphrase, and unpack what Packer and Cole have accomplished.
Human evolution — Where from here? | SpringerLink
CET and SIT are commonly understood to have been constructed to solve different sorts of problems; the former is mostly of interest to students of evolutionary and cultural theory, the latter mostly to developmentalists. Although there were other mathematical treatments of cultural evolution before Boyd and Richerson , their version of CET is seen as a landmark work; its popularity, and indeed plausibly, depended on the rigor of its mathematical modeling of the evolution of social learning. In particular, they were able to demonstrate that social learning would outcompete individual trial-and-error learning in circumstances where a individual learning is costly, b environmental change is relatively slow, and c selection is negative frequency dependent, meaning that social learning would lose its competitive edge when it becomes a very common strategy.
The motivation for CET includes some degree of dissatisfaction with the neo-Darwinian modern synthetic conception of evolution as a process whereby natural selection acts solely on populations of genes; the products of social learning, including culture, afford a second stable source of variation upon which selection can act.
There are numerous examples of cultural information affecting gene frequencies in populations, the canonical one being lactase persistence; the rapid evolution of lactose tolerance has also been documented in several populations. The fact that pastoralism could strongly select for particular genes also underscored the extent to which adaptation to the Holocene could affect evolutionary processes.
This enabled gene-culture coevolutionary views that would compete with the sort of evolutionary psychology that equated evolutionary change to genetic change with the attendant implication that evolutionary change, given its dependence on genetic change, must be slow and humans must be adapted to a long-vanished way of life that existed in the Pleistocene.
Similarly, human behavioral ecology is an evolutionary theory that studies and conceives of adaptation as a real-time process involving differential reproduction and survival in a modern context. For more detail about these major evolutionary theories of human behavior, see Laland and Brown, One could say that all three assume the neo-Darwinian metatheory. Thus, although CET explicitly includes what Jablonka and Lamb would later call a second dimension of inheritance, and human behavioral ecology explicitly includes dynamic real-time individual processes of adaptation in a way that arguably might make some room for developmental systems theory DST , both approaches to human behavior do so within what Wray and colleagues call standard evolutionary theory.
Similarly, the theory of Tomasello and colleagues, which is not an evolutionary theory in the way that are the aforementioned but rather a developmental theory that relies on evolutionary evidence, also does not challenge conventional neo-Darwinian thought. The reasons are essentially the same and include additional considerations about the importance and nature of psychological states that are only shared with evolutionary psychology and not CET or human behavioral ecology. Despite evolutionary psychologists and Tomasello both seeming comfortable in their use of neo-Darwinian adaptationist reasoning and a representational theory of mind, evolutionary psychologists of course envision a large number of independent evolved information processing mechanisms each adapted for its own function; Tomasello postulates a more domain-general mind and a very small number of specialized information processing mechanisms.
To a first approximation, one can take the EES to be predicated on the conviction that evolutionists should not put undue emphasis on a single factor, be it genetic, epigenetic, cultural, material, psychological, behavioral, and so on. NCT trades on an active view of the evolutionary process and arguably, by extension, one could think of DST in a similar manner and even evoke reciprocal causation.
Changes in population-level gene frequencies through mutation and recombination do not explain the evolution of developmental processes; ones needs to evoke evo-devo concepts like conservation, regulator genes, and so forth. Thus, also evo-devo cannot be accommodated within the MS and shows something about the limits of neo-Darwinism; it is an entirely separate question whether grouping evo-devo together with a variety of phenomena and theories adds up to anything like an alternative general evolutionary metatheory. To make things even muddier, in addition to evo-devo, NCT, and DST, the EES is also said to be constituted by, for example, complexity theory, multilevel selection theory, genomics and networks theory, epigenetic inheritance, plasticity and accommodation, evolvability and modularity, niche construction, contingency, and ecology e.
Although this is an important collection of topics and approaches, I think it is fair to say that the aforementioned do not and arguably cannot provide a metatheoretical alternative to the MS because they hold few principles and commitments in common. This is not surprising if the purpose of the EES is to serve as criticism of the MS rather than to serve as a general alternative framework.
It is important as well that we subject neo-Darwinism — and for that matter any explanatory framework with broad utility — to due scrutiny. As such, Packer and Cole need not have taken on the implicit burden that evolutionary processes in general involve an active organism changing the process of adaptation and selection, or that evolutionary systems analyses can be usefully applied at phylogenetically remote levels of biological organization.
Although Packer and Cole do assume and claim to build on an extended alternative, their points mostly speak for themselves. To my mind, the debate that Packer and Cole briefly allude to between Laland et al. Framed this way, it would seem that the at least provisional answer should be no; niche construction might be fairly common but is certainly not general across species and a developmental systems take on the evolution of all species, or even e.
Of course, it is probably still going to matter which aspect of phenotypic development in which we are interested and whether evolutionary considerations are, strictly speaking, relevant in a particular case.
- The genre of non juridical oracle in Ancient Egypt (dissertation).
- Dept. of Human Evolution | Philipp Gunz | Publications.
- My Future (Middle School Survival Series)!
For, as far as I can tell, although development is usually fruitfully conceptualized as occurring within various sorts of systems, it is not as obvious, and certainly not nearly as widely agreed upon, that a systems level of analysis is obligatory in human evolutionary studies. They argue, in turn, that the deontic nature of human institutions is critical because human agents are bound by, for example, obligations to family that are not mere matters of convention in the way that they are envisioned, for example, in CET.
In addition, Packer and Cole claim that human institutions bind obligations over many time scales from the distant past to the momentary present to the far future; as such, human institutions themselves have the potential to guide evolution. Finally, and furthermore, the human capacity for self-consciousness is tied up with and emerges through the deontic niche; human social cognitive development therefore occurs within human institutions. One could, and arguably should, give some pause as to whether absence of explicit learning is a sufficient criterion for a skill to be seen as biologically prepared i.
I would imagine though that Michael Tomasello, like the evolutionary psychologists he sometimes criticizes, might be left scratching his head why his extensive empirical research attempting to test his theory is given short shrift. To wit: based on observational and experimental studies of human and nonhuman primates, why and how did human x develop capacity y?
Answer: maturation. It reminds me of using, for example, habituation studies, studies of which Tomasello and colleagues have been critical e. To be clear, both things might be the case, but they tell us very little about development. Here, then, is a concern. After all, it is not obvious that the kin qua first and critical institution could hold up to the same scrutiny.
In addition, I would suspect that Tomasello is likely to continue to wonder how it is that human infants could possess a capacity for shared or collective intentions that eludes our great ape cousins, for it is fairly clear that raising a chimpanzee as a human infant has diminishing returns.