BIO3400 1nd Edition Exam 5 Study Guide Lectures 21 24 Lecture 21 I Origin of Amniotes a Early carboniferous b Small agile probably insectivorous c Derived characteristics i Amniotic egg ii Waterproof skin d Major diversification followed II Amniotic Egg a Aka cleidoic egg Greek meaning closed b Leathery and flexible or calcified and rigid i Provides mechanical protection ii Allows passage of respiratory gases and water vapor c Albumin reservoir of water and protein d Yolk energy supply for embryo III Sauropsids vs Synapsids a Very early after the first amniotes appeared two major lineages diverged b Distinguished by the pattern of bones in the skill c Sauropsids turtles lizards snakes birds many many extinct taxa ex dinosaurs d Synapsids mammals marsupials monotremes many extinct taxa mammal like IV Largest Mass Extinction Permian Triassic 252 MYA a 96 of species went extinct b Synapsids decline mammal lineage c Followed by the Age of the Dinosaurs 200 66 MYA d Thought to be due to volcanic activity Lecture 22 I The Earliest Hominins a Ardipithecus i From Ethiopia Africa ii Large sample of remains iii Cranium is very ape like iv Small chimp brain 300 350 cc b Australopithecus i Small brain 375 400 cc ii Pelvis is more human like iii Big toe not divergent iv Evidence for foot arches foot is a rigid propulsive lever like humans 1 Footprints c Genus Paranthropus i Postcraniium similar to Australopithecus 1 Similar commitment to bipedalism ii Brain slightly larger but still apelike iii Chewing apparatus specialized 1 Very large molars premolars and jaws 2 Great chewing muscle leverage 3 Mechanically challenging diet 4 EXTINCT LINEAGE d Early Homo i Found in eastern Africa ii Larger brain compared to Ardipithecus iii Tool usage e Homo erectus i Found in Africa and Eurasia first time having fossils outside Africa ii Oldest 1 8 million years ago iii Humanlike limb proportions and body size iv More complex tools 1 By 1 6 MYA a Standardized tools hand axes with characteristic shape b Evidence of transport of raw materials c Suggests foresight and planning f Later Homo i After 200 000 years 1 Multiple distinct populations spread across Africa and Eurasia 2 Including Neandertals and modern humans 3 Species status debated a Different populations of same species b or multiple species H neanderthalensis H sapiens Lecture 23 I Human Evolution Overview a The chimp and human lineages diverged about 6 8 MYA i Major expansion of grassland habitat ii Advantages of bipedalism b Fossil record i We have a very good record of transitional fossils that help us chart the general course of human evolution ii What changed first 1 Bipedalism 2 Brain size change occurs much later II What is ecology a the study of relationships between organisms and their environment Molles 2010 III IV V VI b the scientific study of the interactions that determine the distribution and abundance of organisms Krebs 72 Evolution and Ecology are closely linked evolutionary perspective a Population growth and regulation b Predatory prey relationships c Ecological niches and adaptive radiations Levels of Ecology a Individuals b Communities c Populations d Ecosystem Population Growth and Regulation a What is a population i A group of individuals of a single species inhabiting a specific area 1 A single meadow 2 The Aland Islands 3 Europe b Fundamental Characteristics of Populations i Distribution Where is it ii Density How many individuals per unit area iii Abundance How many total individuals are present iv Population Dynamics changes in the distribution and abundance of populations c Ecological Niches i Hutchinson s n dimensional hypervolume All of the environmental factors conditions and resources necessary for a viable population ii Fundamental niche potential niche in the absence of species interactions iii Realized niche actual niche limited by competition predation disease and other species interactions iv Niche does NOT equal habitat Patterns of Survival and Reproduction a How do we measure age specific survivorship in a population i Cohort life table follow a single cohort all born at the same time through time ii Statis life table measure age and survivorship of a large number of individuals over a short time period iii Age distribution estimate from the proportions of individuals in each age class Lecture 24 I Patterns of Survival and Reproduction II Age Distributions a What is an age distribution Proportions of organism in each age class b What can they tell us Are older organisms replacing themselves Is the III population declining inclining or steady Isle of Rum Red Deer Project IN CLASS PROJECT