Biological Anthropology 2/27- Taxonomy and classification - Often considered a reductionist approach- The Linnaean Hierarchyo 7 levels from kingdom to species Bacteria, protozoa, chromista, plantae, fungi, animaliao Bionomial nomenclatureo Genus and specieso Based on similarity between organisms Genus-Homoo Species-Sapiens; descriptorso Trinomial nomenclature Homo sapien sapienso Species are the only real entity defined on basis of interbreeding in nature- Use of reductionist approach looks at the degree of similarities and differences using comparisonso Phylum-Chordata-animals w/ a hollow dorsal nerve cord Subphylum-Vertebrata-animals w/ a backboneo Class-Mammaliao Order-Primates (humans, apes)o Family-hominidae (apes & humans)o Genus-Homo, humans and their most immediate ancestorso Specific name-sapiens- Primate characteristicso Limbs and locomotion Pentadactyl and prehensile hands and feet Nails instead of claws Opposable thumbs and big toes Tendency toward erect trunk posture (orthograde posture) Retention of the clavicle Generalized skeleton Separate bones in the forearm (radius & ulna) and in lower leg (tibia & fibula)- Teeth and dieto Dentition generalized by all 4 tooth types presento Diets are generalized and varied (omnivores)- Sense, brain and behavior o Reduction of the snout and olfaction (3D & depth perception)o Increased reliance on binocular visiono Increased size and complexity of the braino A more efficient fetal nourishmento An increased reliance on complex learned behavior- Consequences of genetic transformations are changes in the adaptations and the diversity of populations- Microevolution is the degree of change that is usually below the species level and its relatively small- Macroevolution is the accumulated change is more dramatic and usually causes change above the species level; it may lead to speciation events- When speciation occurs the populations presumably become genetically isolated- Phylogenetics are concerned w/ reconstructing the evolutionary branches and sequences in order to understand how closely related species became what they are now- Primates evolutionary history of nearly 65 MYA and so this task is hard for the Order Primates- Reconstructing a phylogeny is based on identifying groups of related species by their morphological similarities- Not all similarities are equalo Some features are similar b/c of their presence in a common ancestoro Features known as homologous features have a structural similarity but don’t have a functional similarityo An example of a homology is pentadactyl limb structureo Biologists agree that organisms should be grouped on the basis of shared specializations that distinguish them from their ancestorso Body hair is a specialization- Apes lack tails- Monkeys, prossimians and lizards have tailso That has no value in giving us an idea about the evolutionary relationships across particular animals- When a cluster of different species possess a number of similar traits or specializations - Interpreted as indicating that these species share a unique phylogenetic history- Many forms can come up with similarities on their own- Homoplastic features are similar by function rather than by inheritance from a common ancestor- Homoplasies are similar without being homologous- This type can occur due to o Parallelism o Convergence o Analogyo Parallelism is the development of homoplasies in animals with a fairly recent and common ancestry-here the characteristics are based on or channeled by that common ancestry A few monkey and prosimian species of primates have also lost their tails similar to humans and apes Dentition, upper limbs, locomotor behavior and social behavior Primates of the New and Old World have been separated for 35 MY but share numerous examples of parallel evolution-especially in joint