Darwin’s Evolutionary Theory: Contributions & Shortcomings

Darwin's  1837 "Tree of Life" sketch from his notebooks (Stanford University)

Darwin’s 1837 “Tree of Life” sketch from his notebooks (Stanford University)

Biological evolution occurs when a population evolves physical changes that allow it to better survive and reproduce in its environment. It’s discovery was first published by Charles Darwin’s in 1859 in his book On the Origin of Species by Means of Natural Selection in 1859 (later re-published as The Origin of Species). Darwin’s called his theory “descent with modification” through the process of “natural selection.”  He believed that environmental pressures–nature–selected for the most advantageous traits in living things much in the same way as domestic animals were selectively bred for desirable traits using “artificial selection.” Continue reading

Keeping it together: Why some societies & cultures cohere & some persist

Why do some social groups or societies persist for generations and others disappear in only a few generations? How is the integration and coherence of a society developed and maintained? Benedict, Gluckman, Barth, and Wilson all believed in specific mechanisms that sustained traditional values and societies over time. In this paper I will compare and contrast the various explanations for cultural coherence and longevity put forth by Ruth Benedict, Max Gluckman, Fredrik Barth and David Sloan Wilson. Continue reading

Genetic, geographic & cultural factors that cause sickle-cell anemia

It is important to note that even genetic diseases are caused by multiple social, environmental and biological factors. This is particularly true in the case of sickle-cell anemia, a genetically inherited blood disorder usually found in people with West African ancestry (PBS 2001).  The following paper will summarize the genetic, geographic and cultural factors that contribute to the incidence of sickle-cell anemia and why this disease is called a “balanced polymorphism”. Continue reading

The Scientific Method and Biological Anthropology

This paper discusses the relationship between the scientific method and physical anthropology. The scientific method is a research process whereby a question or problem is posed, a provisional explanation called an hypothesis is made that is then tested through the gathering of data (e.g. evidence) from observation or experimentation. Data is scientific information from which conclusions can be drawn. The word “data” is plural for “datum”. Since physical anthropology is a scientific discipline, it focuses on gathering quantitative data (e.g. data that can be expressed numerically) and empirical data (e.g. data that can be experienced) through observation or experimentation.  Thus the scientific method is an empirical approach to gaining knowledge from experience through observation or experimentation. The word “empirical” is from the Latin empiricus, meaning “experienced” (Jurmain 2010:16). If a phenomenon cannot be experienced with one’s five senses (sight, touch, taste, hearing and sensation) then it is not empirical.  Science itself is provisional knowledge that is gained and is constantly being refined through the scientific method of observation or experimentation of empirical data. The word “science” is from the Latin scientia, meaning “knowledge” (Jurmain 2010:16). Continue reading

Hardy-Weinberg Equilibrium Theory

The Hardy-Weinberg Equilibrium Theory is a simple mathematical model for the modern definition of evolution  that can be used to track the changes in allele frequencies within a population from one generation to the next. It is based on the idea of that no evolution– genetic equilibrium–is statistically unlikely. However, the hypothetical instance of no evolution can serve as a baseline in order to estimate and predict instances of allele frequency changes (evolutionary change) in descendent populations solely based on the proportion of phenotypic variances within a population (Jurmain 2010:438). Continue reading

The Five Forces of Evolution

Evolve FishHave you ever wondered why there is a new flu shot each year? Or, why people who are traditionally from the same region have similar physical features? Or, why it’s probably a bad idea to marry your cousin? And, why are Darwin’s finches so important?  Biological evolution occurs when a population evolves physical changes that allow it to better survive and reproduce in its environment. It’s discovery was first published by Charles Darwin’s in 1859 in his book On the Origin of Species by Means of Natural Selection in 1859 (later re-published as The Origin of Species) where he tracked the variation in finch beaks and other kinds of similarities and differences in other species as well.

This paper will explain the fundamental cause of the variation of all life: evolution. In particular I will explain evolution talking about the five forces or mechanisms of evolutionary change in a population: genetic mutation, genetic recombination, gene flow, genetic drift and natural selection. Continue reading