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Excited about Energetics
Published 10/9/2013 in Biology, Culture, and Evolution
Author Andrea
Author Biography: James Josh Snodgrass Dr. J. Snodgrass’ research interest cover almost every topic related to human biology: adaptations and evolution, nutrition, epidemiology, and the social/behavioral patterns that emerge from them. Specifically, he focuses on elucidating the effect of economic and cultural change plus chronic psychosocial stress on human health patterns, human adaptations to environmental extremes, and energetics and the role of evolution in shaping the human diet. His ongoing work includes the Indigenous Siberian Health and Adaptation Project, The Shuar Health and Life History Project in Ecuador, and his collaborative efforts in studying stress, discrimination, and health among Latin American immigrants in Oregon. His publication topics range from the metabolic correlates to hominid brain expansion to the immergence of obesity in indigenous Siberian populations to muscle mass scaling in primates. He has even published work in the Journal of Forensic Science concerning sex related differences in the aging of the... read more ❯
The Cotton Top Tamarin
Published 10/7/2013 in The Monkey Speaks His Mind
Author kmgrow
  Saguinus oedipus, or more commonly known as the cotton top tamarin is a New World primate that belongs to the Callitrichidae family. The cotton top tamarin can be found climbing and jumping through the tree tops of tropical forests in their home country of Columbia in South America. These primates were first described by Linnaeus in 1758. These punk rock primates are known for the fluffy white hair that grows from the tops of their heads. Each cotton top tamarin has their own unique hair style: short, long, sleek or furry. Approximately the size of a squirrel and weighing less than one pound, the cotton top tamarin is known for being one of the smallest primates. These tamarins along with other members of the Callitrichidae family have sharp nails on all... read more ❯
Obesity, Diabetes, and Lactose-Tolerance: A Summary of Human Nutritional Evolution
Published 10/7/2013 in Biology, Culture, and Evolution
Author peadams
The Author of this chapter, William R. Leonard, is currently a professor of anthropology at Northwestern University. He holds the title at this university as the Abraham Harris Professor of Anthropology. He He received his PhD from the University of Michigan in 1987. His research interests include biological anthropology, adaptability, growth and development, and nutrition focusing on populations in South America, Asia, and the United States. His most recent publication was on the topic of precursors to over-nutrition and the effects of household market food expenditures on body composition among the Tsimane in Bolivia. The ecological variation of available food has been an important factor throughout the history of human evolution and continues to shape the biology of traditional human populations today. The relationship that humans share with their environments (i.e., acquisition and expenditure of energy) has adaptive consequences for both survival and reproduction. Humans are similar to other primates in... read more ❯
Tufted Capuchins
Published 9/30/2013 in The Monkey Speaks His Mind
Author ctgreen2
Cebus apella of the Cebidae family is better known as the tufted capuchin.  The tufted capuchin is a New World primate located in South America.  Tufted capuchins spend most of their time within the mid-canopy of rain-forests; however they do sometimes move to the ground to play and forage. The tufted capuchin gets its name from the tufts of dark hair that form above its ears, that makes it appear as if it is wearing a cap (or Mickey Mouse ears).  Tufted capuchins are sexually dimorphic, with the average weight of the male being 34% larger than that of the female.  Wild male tufted capuchins have an average weight of 8 lbs, and the average female weighs 5.5 lbs; though captive capuchins can grow larger.  Tufted capuchins move quadrupedally,... read more ❯
Climate-induced Stress
Published 9/30/2013 in Biology, Culture, and Evolution
Author Emily Barron
Author Biographies Cynthia M. Beall PhD, is a physical anthropologist at Case Western Reserve University, whose special interests are human growth and development, aging, human adaptability and medical ecology.  She previously conducted research on growth and development and infant morbidity/mortality in Andean populations, high altitude hypoxia and aging in Nepal and Bolivia and physical activity, physical fitness and aging in Nepal.  Her current research in Tibet is on high-altitude human adaptability and aging and diet.  Dr. Beall is a member of the U.S. National Academy of Sciences and she is the Co-Director for the Center on Research for Tibet.   Nina G. Jablonski is Distinguished Professor of Anthropology at The Pennsylvania State University.  A biological anthropologist and paleobiologist, she studies the evolution of adaptations to the environment in Old World primates including humans.  Her research is focused in two major areas: the evolutionary history of Old World monkeys, and on the evolution of human skin... read more ❯
Biological Memories and Epigenetics
About the Authors Zaneta M. Thayer is a biological anthropologist pursuing her doctorate at Northwestern University, and she has a B.A. in anthropology and biology from Dartmouth College. Thayer is interested in how the environment affects patterns of human biological variation, particularly during early development. Her primary research has been on the epigenetic effects seen in fetal development. One of her long term goals is to unite developmental biology with the Modern Synthesis as an expansion of modern evolutionary theory. https://sites.google.com/a/u.northwestern.edu/zaneta-thayer/ Chris Kuzawa, a Professor  at Northwestern University, is a biological anthropologist with a background in epidemiology. He received both his PhD and his MsPH (Masters of Science in Public Health) from Emory in 2001.  He focuses on developmental biology and the diseases and effects that early postnatal environments have on humans. The premise of this research is that what a mother eats during pregnancy, her access to adequate prenatal care, or her... read more ❯
Of Epigenetic Aggression & Silver Foxes: Updated--Now with More Methylation!
Epigenetic Mechanisms, Quick &  Dirty Jablonka & Raz (2009) show us this elegant illustration of broad and narrow epigenetic transmission. Epigenetic inheritance in the broad sense is the inheritance of developmental variations that do not stem from differences in the sequence of DNA...information transference that can take place through developmental interactions between mother and offspring..., through social learning..., and through symbolic communication. We...define cellular epigenetic inheritance as the transmission from mother cell to daughter cell of variations that are not the result of differences in DNA base sequence and/or the present environment.  Transmission can be through chromatin marks, through RNAs, through self-reconstructing three-dimensional structures, and through self-sustaining metabolic loops. In the single-cell "bottleneck" variety of epigenetic inheritance (pathway a in the above diagram) Jablonka &  Raz focus on... The environment may induce epigenetic variation by directly affecting the germline or by affecting germ cells through the mediation of the soma, but, in either case, subsequent... read more ❯
Epigenetics...Epige-what-ics?
Published 9/24/2013 in Biology, Culture, and Evolution
Author mmcheatham
Mechanisms of Cellular Epigenetic Inheritance Epigenetic inheritance is basically the observation that offspring may inherit altered traits due to its parents past experiences. So a parents experiences, in the form of epigenetic tags, can be passed down to future generations. Epigenetic inheritance systems are  the processes and mechanisms that underlie cellular inheritance.  There are four types of EISs recognized today and they are.... EIS based on self sustaining regulatory loops EIS based on three-dimensional templating Chromatin marking EIS RNA mediated EIS All of these can contribute to between-generation epigenetic inheritance. SELF SUSTAINING LOOPS: These are metabolic circuits through which different patterns of activity can be maintained resulting in alternative heritable phenotypes. The early studies of the loops involved the bistability of the lac operon of Escherchia coli and this system has been analyzed at molecular and theoretical levels. The studies showed that when inducer concentrations are low, genetically identical cells can generate two alternative, true breeding, stable... read more ❯
The Philippine Tarsier
Published 9/18/2013 in The Monkey Speaks His Mind
Author nhgraham
This cute little guy is a Philippine tarsier (Carlito syrichta). He is often called “the world’s smallest monkey,” but this is not fully accurate. The problem isn’t one of size, but of classification. Different scientists classify the tarsiers either as prosimians or as anthropoids. Whatever the classification, it is clear that tarsiers share traits with both groups. Like prosimians, tarsiers are nocturnal and have grooming claws, as well as a bicornuate uterus. However, like anthropoids, tarsiers lack a tapetum but have post-orbital closure and monthly sexual swellings in females. On average, the Philippine tarsier is only 11-14 cm long without the tail, which is about twice the length of the body. They only weigh around 120-130 grams. The species is sexually dimorphic, with males being larger and heavier than females. Their fur is usually gray, and their very long tails are nearly bald, although... read more ❯
Genetically (un)fathomable Variation
Lyle W. Konigsberg This chapter was another that focused heavily on the schematics of genetics including; quantitative genetic, multivariate quantitative genetic, complex segregation, and quantitative trait locus linkage analyses all connecting back to the evolutionary models applying to these quantitative traits. The big questions asked at the beginning of the chapter concerned human biologists and if they should be studying variation within the quantitative genetic framework? What is mostly unknown is that a large portion of variation that is studied today is quantitative already. The example given here was anthropomorphicstudies and longevity studies and how their variability implies quantitative measure. Below are relative ideas to keep in mind from the chapter: Heritability is represented by h^2.  It is defined as the proportion of phenotypic variance due to additive genetic effects.  H^2=  Va/Va+Ve =Va/Vp When there is dominance at one or more loci the concept of heritability becomes more complicated.  Pi= a1 + d1 + e1 If you include variances due... read more ❯

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